Surface discretisation with rectifying strips on Geodesics

The use of geodesic curves of surfaces has enormous potential in architecture due to their multiple properties and easy geometric control using digital graphic tools. Among their numerous properties, the geodesic curves of a surface are the paths along which straight strips can be placed tangentially to the surface. On this basis, a graphical method is proposed to discretize surfaces using straight strips, which optimizes material consumption since rectangular straight strips take advantage of 100% of the material in the cutting process. The contribution of the article consists of presenting the geometric constraints that characterize this type of panelling from the idea of “rectifying surface”, considering the material inextensible. Experimental prototypes that have been part of the research are also described and the final theoretical results are presented

Structural Models based on Minimal Surfaces and Geodesics

This article presents the results of research carried out with respect to the geometric, formal and structural adaptation of minimal surfaces. These surfaces were discretized into strips developable on geodesic curves, and then used for the construction of timber gridshells. For this project, both physical and virtual models derived from the same geometric models were used. The objective was to demonstrate the validity of the use of models and the transformation that modelling is undergoing due to the use of digital tools, both software and hardware. These include, on the one hand, drawing and analysis software and, on the other, digitally controlled fabrication tools. This research focuses specifically on the design and construction of the Scherk Pavilion, a space where the results of various experiments in which the common factor was the use of models was transferred to a real scale

EFECTOS A LARGO PLAZO DE LAS AMPLIACIONES DE CAPITAL EN EL MERCADO ESPAÑOL

This paper analyses the long-run shareholders¿ wealth effect and the firms¿ operating performance of the rights offerings decision in Spain. The evidence shows that the stock price of firms¿ issuing rights substantially under-perform the different benchmarks employed. It has also been observed that these companies experience a decrease in the accounting profitability for some pre- to post-issue periods. The optimism about the investment opportunities of issuing firms could explain these results. Este trabajo presenta evidencia empírica del efecto que los aumentos de capital realizados en el mercado español tienen a largo plazo en la rentabilidad del accionista y en los resultados contables empresariales. Se ha observado que los inversores revisan a la baja el precio de las acciones de las empresas que adoptan esta decisión y que estos resultados son robustos a las diferentes referencias utilizadas para calcular las rentabilidades anormales. También se ha constatado que las compañías emisoras experimentan una disminución en los resultados contables en el año del aumento de capital y en los dos siguientes. El excesivo optimismo acerca de las oportunidades de inversión de las empresas que deciden ampliar capital podría explicar esta evidencia.ampliaciones de capital, rentabilidades a largo plazo, eficiencia del mercado. rights issues, long-run performance, market efficiency.

Cactus Pavilion: experimental architecture with folded developable surface

PREPRINTCACTUS PAVILION es un pabellón madera diseñado como centro de interpretación itinerante del Proyecto de Salvamento del Patrimonio Arquitectónico y Natural de Santiago de Anaya, Valle del Mezquital, México. El pabellón (Fig.1) ha sido concebido y diseñado en el Departamento de Ingeniería Gráfica de la Universidad de Sevilla, en colaboración con Fablab Donostia de la Universidad del País Vasco. Se propone una arquitectura efímera biomimética en forma de cactus hueco de madera, realizada con tiras desarrollables formada por paneles de 3mm de espesor. Al igual que en otras experiencias anteriores, el pabellón se ha diseñado con herramientas CAD-CAM y se ha fabricado digitalmente mediante una fresadora de control numérico CNC de tres ejes. Cactus Pavilion ha sido galardonado con una Mención Honorífica LAKA COMPETITION’18 https://lakareacts.com/winners/cact us-pavilion

Autonomous Wristband Placement in a Moving Hand for Victims in Search and Rescue Scenarios With a Mobile Manipulator.

In this letter, we present an autonomous method for the placement of a sensorized wristband to victims in a Search-And-Rescue (SAR) scenario. For this purpose, an all-terrain mobile robot includes a mobile manipulator, which End-Effector (EE) is equipped with a detachable sensorized wristband. The wristband consists of two links with a shared shaft and a spring. This configuration allows the wristband to maintain fixed to the EE while moving and get placed around the victim’s forearm once the contact is produced. The method has two differentiated phases: i) The visual moving hand tracking phase, where a 3D vision system detects the victim’s hand pose. At the same time, the robotic manipulator tracks it with a Model Predictive Controller (MPC). ii) The haptic force-controlled phase, where the wristband gets placed around the victim’s forearm controlling the forces exerted. The wristband design is also discussed, considering the magnitude of the force needed for the attachment and the torque the wristband exerts to the forearm. Two experiments are carried out, one in the laboratory to evaluate the performance of the method and the second one in a SAR scenario, with the robotic manipulator integrated with the all-terrain mobile robot. Results show a 97.4% success in the wristband placement procedure and a good performance of the whole system in a large scale disaster exercisePlan Propio de la Universidad de Málaga, y Ministerio de Ciencia, Innovaci ón y Universidades, Gobierno de España, RTI2018-093421-B-I00. Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

Evolution of the Residual Pollution in Soils after Bioremediation Treatments

This study is focused on one of the most important spills that ever happened in Europe, the Aznalcóllar’s mine spill. The extensive application of phytostabilization in the area led to the implementation of the Guadiamar Green Corridor (GGC). Soil physicochemical properties were analyzed and the total concentration of Pb, As, Zn and Cu was measured by X-ray fluorescence (XRF); bioassay using Lactuca sativa L. was applied to assess potential toxicity. Two decades after the accident, some soils affected by residual contamination continue to appear in the area. According to regulatory levels, Pb and As concentrations are exceeded in around 13%and 70%, respectively, in the uppermost part of the soils (first 10 cm). The change in soil properties after bioremediation treatment positively promoted the reduction in the potential mobility of pollutants by the increase in pH, CaCO3 content and organic carbon. Anyway, the bioassay with Lactuca sativa, indicated that around 25% of the soils showed toxicity by the reduction of the root elongation in relation to the control samples. Our results indicate that monitoring of the GGC is still needed, together with the application of soil recovery measures to reduce the potential toxicity in some sectors of the affected area.This research was funded by the Research Project RTI 2018-094327-B-I00 (Ministry of Science, Innovation and Universities) and the Research Groups RNM-269 and RNM-101 (Junta de Andalucía, Spain)

Divergencias del alumnado y del profesorado universitario sobre las dificultades para aplicar la evaluación formativa

La evaluación formativa supone un claro cambio en la forma de plantear la evaluación en la docencia universitaria. Su aplicación no está exenta de cierta controversia, y sobre todo de dificultades, que hacen que alumnado y profesorado tengan distintas perspectivas. El objetivo del presente estudio ha sido comprobar las divergencias del alumnado y del profesorado cuando se diseña y se ponen en práctica sistemas de evaluación formativa. Se ha utilizado un cuestionario para el alumnado (N=3013) y los informes elaborados por el profesorado (N=46) aplicados durante el curso 2012-13. Los resultados muestran que la evaluación formativa es bastante exigente para el alumnado, aunque también muestran una alta satisfacción del alumnado con la misma, particularmente con la calificación. Un inconveniente que refleja el alumnado parece ser la acumulación de trabajo al final del proceso, lo cual resulta paradójico y requiere de una investigación más profunda en el futuro. El profesorado también muestra una alta satisfacción con este tipo de evaluación, aunque tengan una mayor carga de trabajo. Se observan escasas discrepancias entre los dos colectivos (alumnado y profesorado). En el estudio se proponen recomendaciones de puesta en práctica en cuanto al diseño y la planificación para investigaciones futuras. Las limitaciones se observan en cuanto a la población participante en el estudio, con el fin de que puedan generalizarse los resultados.Formative Assessment shows a clear change in how to approach the evaluation of university teaching. The application of Formative Assessment is not without some controversy, and above all difficulties due to students and teachers having different perspectives. The objective of the present study was to check the differences of students and teachers when formative assessment systems are designed and put into practice. A questionnaire was used for students (N = 3013) and a report prepared by the teachers (N = 46). Both were taken from the academic year 2012-13. The results show that formative assessment is quite demanding for students, but also that students are highly satisfied with it, particularly with grades. A problem that the students reflect seems to be the accumulation of work at the end of the process, which is paradoxical and will requires further research in the future. Teachers also show a high satisfaction with this type of assessment, even if they have a greater workload. There are few differences between the two groups (students and teachers). The study proposes recommendations for implementation in terms of design and planning for future research. The limitations of the research can be seen in terms of participating in the study population, so the results can be generalized

Acciones para la mejora de la calidad de los títulos de la UPCT: proyecto de innovación docente (curso 2018-19

Este libro documenta tres trabajos desarrollados en dos de los proyectos de innovación docente correspondientes a la convocatoria 2018‐19 del Vicerrectorado de Profesorado e Innovación Docente de la Universidad Politécnica de Cartagena (UPCT): Revisión y actualización del Proyecto 7 competencias UPCT, Influencia de los indicadores académicos en los resultados de las encuestas de satisfacción con la actividad docente de la UPCT y Un modelo para estimar la distribución de la carga de trabajo del estudiante a partir del cronograma conjunto. Esta forma de entender y poner en práctica la innovación docente sigue siendo necesaria en la UPCT, ya que ha permitido generar herramientas y establecer criterios que son aplicables a todos los títulos de nuestra universidad, siempre desde la perspectiva de los programas de aseguramiento interno y externo de la calidad de ANECA

Matrix metalloproteinases in age-related macular degeneration (AMD)

Producción CientíficaAge-related macular degeneration (AMD) is a complex, multifactorial and progressive retinal disease affecting millions of people worldwide. In developed countries, it is the leading cause of vision loss and legal blindness among the elderly. Although the pathogenesis of AMD is still barely understood, recent studies have reported that disorders in the regulation of the extracellular matrix (ECM) play an important role in its etiopathogenesis. The dynamic metabolism of the ECM is closely regulated by matrix metalloproteinases (MMPs) and the tissue inhibitors of metalloproteinases (TIMPs). The present review focuses on the crucial processes that occur at the level of the Bruch’s membrane, with special emphasis on MMPs, TIMPs, and the polymorphisms associated with increased susceptibility to AMD development. A systematic literature search was performed, covering the years 1990–2020, using the following keywords: AMD, extracellular matrix, Bruch’s membrane, MMPs, TIMPs, and MMPs polymorphisms in AMD. In both early and advanced AMD, the pathological dynamic changes of ECM structural components are caused by the dysfunction of specific regulators and by the influence of other regulatory systems connected with both genetic and environmental factors. Better insight into the pathological role of MMP/TIMP complexes may lead to the development of new strategies for AMD treatment and prevention

Complications associated with the use of silicone oil in vitreoretinal surgery: A systemic review and meta‐analysis

Producción CientíficaSilicone oil (SO) still represents the main choice for long-term intraocular tamponade in complicated vitreoretinal surgery. This review compared the complications associated with the use of SO and other vitreous substitutes after pars plana vitrectomy in patients with different underlying diseases. Meta-analysis was conducted in accordance with PRISMA guidelines. We retrieved randomized clinical trials (RCTs), retrospective case–control and cohort studies evaluating the risk of using SO, published between 1994 and 2020, conducting a computer-based search of the following databases: PubMed, Web of Science, Scopus and Embase. Primary outcome was the rate of complications such as intraocular hypertension, retinal re-detachment, unexpected vision loss or hypotony. Secondary outcome was to compare the rate of adverse events of different SO viscosities, especially emulsification. Forty-three articles were included. There were significant differences in intraocular hypertension (p = 0.0002, OR = 1.66; 95% CI = 1.27–2.18) and the rate of retinal re-detachment (p < 0.0009, OR = 0.65; 95% CI = 0.50–0.64) between SO and other agents, including placebo. However, there were no differences in other complication rates. Silicone oil (SO)-emulsification rate was non-significantly higher in low than high SO viscosity, and results from other complications were comparable in both groups. The high quality of most of the studies included in this study is noteworthy, which provides some certainty to the conclusions. Among them is the high variability of the SO residence time. The fact that ocular hypertension and not hypotension is related to SO use. A clear relationship is not found for the so-called unexplained vision loss, which affects a significant percentage of eyes. Re-detachment cases are less if SO is used and that surprisingly there does not seem to be a relationship in the percentage of emulsification between the low- and high-viscosity silicones. All these data warrant more standardized prospective studies