Ilusiones de realidad: de la perspectiva del Renacimiento a la realidad virtual

La revolución que en el Renacimiento supuso la invención de la Perspectiva establece la implantación de un modelo que condicionó el desarrollo de toda la historia del dibujo y la pintura, así como la posterior aparición de la fotografía, el cine y el resto de las imágenes contemporáneas generadas por las nuevas tecnologías. El modelo tradicional de representación del espacio propuesto por la perspectiva del Renacimiento continúa vigente, no sólo a través del dibujo y la pintura, sino sobre todo en la fotografía, el cine y la televisión. Sin embargo, los actuales medios informáticos, a la vez que retoman los sistemas de representación tradicionales, plantean la posibilidad de nuevas alternativas a este modelo, ya que la tecnología que utilizan, permite una experimentación del espacio que puede ir más allá de su visualización en la pantalla del ordenador.The revolution which, during the Renaissance, saw the invention of Perspective, laid down the roots of a model which was to condition the development of the entire history of drawing and painting, as well as the subsequent arrival of photography, cinema and all other contemporary images generated by new technologies. The traditional model to represent space provided with perspective during the Renaissance is still valid today, not only in drawing and painting but also, particularly, in photography, cinema and television. Existing computing methods, however, not only reintroduce the traditional system of representation, but also bring about the possibility of new alternatives to this model, given that the technology they use enables the experimentation of space which can go far beyond visualization on a computer screen

El dibujo y los modelos de belleza

En épocas pasadas, la existencia de un modelo ideal que representaba la idea de la belleza llevaba a los artistas a una interpretación del cuerpo humano siempre en función de ese ideal. Hoy día, la pluralidad de visiones en torno al cuerpo humano, hace que en la actualidad difícilmente pueda establecerse un modelo ideal, un canon incuestionable como el que ofrecían los antiguos tratados de anatomía artística. El proyecto titulado “cuerpos” consiste en la realización de varias series de dibujos en los que se reflejan personajes con morfologías muy diversas y en los que se ensayan diversas estrategias y tratamientos dibujísticos con el fin de sacar el máximo partido a las posibilidades expresivas de cada uno de ellos

Eflorescencia de ladrillos cerámicos comunes

En la superficie expuesta de ladrillos cerámicos comunes pueden aparecer luego de ciclos de mojado y secado, depósitos blanquecinos originados en la lixiviación de sales contenidas en los mismos. En este trabajo se informan experiencias realizadas para evaluar los condicionantes del proceso de lixiviación, en particular los vínculos con las características del material.White deposits due to the lixiviation of salts can appear at the exposed surface of ceramic bricks when they are submitted to several cycles of wetting and drying. This paper presents experiences realized to evaluate the characteristics and factors that affect this process

El proceso del dibujo

Analizaremos el proceso del dibujo, desde la percepción de las formas, hasta la expresión de la idea, materializada a través de los gestos que, fijados sobre un soporte, dan forma a esa idea

From Ethnomedicine to Plant Biotechnology and Machine Learning: The Valorization of the Medicinal Plant Bryophyllum sp.

The subgenus Bryophyllum includes about 25 plant species native to Madagascar, and is widely used in traditional medicine worldwide. Different formulations from Bryophyllum have been employed for the treatment of several ailments, including infections, gynecological disorders, and chronic diseases, such as diabetes, neurological and neoplastic diseases. Two major families of secondary metabolites have been reported as responsible for these bioactivities: phenolic compounds and bufadienolides. These compounds are found in limited amounts in plants because they are biosynthesized in response to different biotic and abiotic stresses. Therefore, novel approaches should be undertaken with the aim of achieving the phytochemical valorization of Bryophyllum sp., allowing a sustainable production that prevents from a massive exploitation of wild plant resources. This review focuses on the study of phytoconstituents reported on Bryophyllum sp.; the application of plant tissue culture methodology as a reliable tool for the valorization of bioactive compounds; and the application of machine learning technology to model and optimize the full phytochemical potential of Bryophyllum sp. As a result, Bryophyllum species can be considered as a promising source of plant bioactive compounds, with enormous antioxidant and anticancer potential, which could be used for their large-scale biotechnological exploitation in cosmetic, food, and pharmaceutical industriesThis research was funded by Xunta de Galicia through “Red de Uso Sostenible de los Recursos Naturales y Agroalimentarios” (REDUSO, grant number ED431D 2017/18) and “Cluster of Agricultural Research and Development” (CITACA Strategic Partnership, gran numbered ED431E 2018/07). The authors acknowledge the FPU grant awarded to Pascual García-Pérez from the Spanish Ministry of Education (grant number FPU15/04849)S

Spanish Market Integration at the end of the 19th Century. Wheat Prices between 1891 and 1905

The degree of development of Spanish agriculture at the end of the XIX century and the beginning of XX is a controversial issue. In this respect the study of the integration of the domestic market could provide new evidence since the degree of the market integration can be considered an indicator of economic development. By using regional wheat prices this paper analyzes the Spanish market integration between 1891 and 1905. With this aim in mind we employ the usual cointegration approach as well as an alternative method based on spectral analysis that allows taking into consideration the existence of no synchronized cycles.El grado de desarrollo de la agricultura española a finales del siglo XIX y principios de XX es una cuestión controvertida y el análisis de la integración del mercado interior puede aportar evidencias que contribuyan a matizar esta tesis. En general se considera que el grado de integración de mercado es un indicador del desarrollo económico. Este trabajo analiza empíricamente la cuestión de la integración del mercado interior entre 1891 y 1905 a partir de los precios del trigo de las diferentes regiones. A tal fin se presenta además del modelo de cointegración predominante en la actualidad un mètodo alternativo, la descomposición espectral, que permite tomar en consideración la existencia de ciclos no sincronizados

Machine Learning Technology Reveals the Concealed Interactions of Phytohormones on Medicinal Plant In Vitro Organogenesis

Organogenesis constitutes the biological feature driving plant in vitro regeneration, in which the role of plant hormones is crucial. The use of machine learning (ML) technology stands out as a novel approach to characterize the combined role of two phytohormones, the auxin indoleacetic acid (IAA) and the cytokinin 6-benzylaminopurine (BAP), on the in vitro organogenesis of unexploited medicinal plants from the Bryophyllum subgenus. The predictive model generated by neurofuzzy logic, a combination of artificial neural networks (ANNs) and fuzzy logic algorithms, was able to reveal the critical factors affecting such multifactorial process over the experimental dataset collected. The rules obtained along with the model allowed to decipher that BAP had a pleiotropic effect on the Bryophyllum spp., as it caused different organogenetic responses depending on its concentration and the genotype, including direct and indirect shoot organogenesis and callus formation. On the contrary, IAA showed an inhibiting role, restricted to indirect shoot regeneration. In this work, neurofuzzy logic emerged as a cutting-edge method to characterize the mechanism of action of two phytohormones, leading to the optimization of plant tissue culture protocols with high large-scale biotechnological applicabilityThe authors acknowledge the FPU grant awarded to Pascual García-Pérez from the Spanish Ministry of Education (grant number FPU15/04849)S

Beyond Avelino's scientific achievements: The building process of a community in catalysis

[EN] The scientific career of Avelino has recently been reviewed in some detail [1] and the contributions included in this special issue provide additional valuable and extensive insights into several aspects of his activities from a variety of perspectives, written with the purpose of completing the picture of Avelino as the author of outstanding breakthroughs in zeolite science and catalysis. But, it is precisely his excellence in science that motivates some key questions that have never been properly addressed, not at least in printing form: how all these achievements came into being? What is the nature of the process that has made such wide range of innovations possible? How the material and human resources required for that successful process were gathered and organized? These questions are usually not of primary concern for scientific journals, as this one is, and are in general best regarded as more suitable for historically oriented publications, and even for social and philosophical aspects of the scientific research. However, we think that these questions are relevant to those scientists who are actively contributing to the fields that Avelino has explored so successfully over the years, as well as to all those who wish to understand through the study of Avelino's career how science is practiced and organized as a human activity.The authors are very grateful to Prof Vicente Fornes for providing us some invaluable information that has been included in this article. Unfortunately, Prof Fornes has refused to appear on the list of authors of this article. The authors also thank Dra. Julia Aguilar, who belonged to ITQ, for providing us with a copy of the picture included in Fig. 2. Also, the Generalitat Valenciana, Conselleria d'Innovacio, Universitats, Ciencia i Societat Digital is acknowledged for their funding via project Prometeo/2021/077.Miro, P.; Lázaro, J.; Pérez Pascual, M.; Frontela, J.; Rey Garcia, F.; Pérez Pariente, J. (2023). Beyond Avelino's scientific achievements: The building process of a community in catalysis. Microporous and Mesoporous Materials. 358. https://doi.org/10.1016/j.micromeso.2022.11240335

Adsorption of gallic acid, propyl gallate and polyphenols from Bryophyllum extracts on activated carbon

The adsorption of gallic acid (GA) and propyl gallate (PG) on activated carbon (AC) was studied as a function of the AC mass and temperature. Clean first order behavior was obtained for at least three half-lives and the equilibrium was reached after ∼4 h contact time. An increase in the temperature (T = 20–40 °C) increases their adsorption rate constant values (k1) by 2.5 fold but has a negligible effect on the amount of antioxidant adsorbed per mass of AC at equilibrium. We also analyzed the adsorption process of polyphenols from Bryophyllum extracts and ca 100% of the total amount of the polyphenols in the extract were adsorbed when using 7 mg of AC. Results can be explained on the basis of the Freundlich isotherm but do not fit the Langmuir model. Results suggest that the combination of emerging in vitro plant culture technologies with adsorption on activated carbon can be successfully employed to remove important amounts of bioactive compounds from plant extracts by employing effective, sustainable and environmental friendly proceduresXunta de Galicia | Ref. ED431D 2017/18Xunta de Galicia | Ref. ED431E 2018/07Ministerio de Educación, Cultura y Deporte | Ref. FPU15/04849Xunta de Galicia | Ref. POS-B/2016/01

Thermal characterization of Montmorillonite clays saturated with various cations

Emanation thermal analysis (ETA), thermogravimetry and high temperature XRD were used to characterize the thermal behavior during dehydration of natural Na montmorillonite (Upton Wyoming, USA) and homoionic montmorillonite (MMT) samples saturated with different cations, i.e. Li+, Cs+, NH 4 +, Mg2+ and Al3+. ETA results characterized radon mobility and microstructure changes that accompanied the mass loss of the samples due to dehydration on heating in air. A collapse of interlayer space between the silicate sheets after water release from the MMT samples was characterized by a decrease of the radon release rate, ΔE. Decreases in c-axis basal spacing (d 001) values determined from XRD patterns for the different montmorillonite samples follow the sequence: Mg−MMT>Al−MMT>Li−MMT>Na−MMT>NH4−MMT>Cs−MMT The decrease of the radon release rate (ΔE) determined by ETA that characterized microstructure changes due to collapse of interlayer space corresponded well to differences in the c-axis basal spacing (Δd 001) values determined from the XRD patterns before and after samples dehydration.Ministry of Education of Czech Republic LA–292España Ministerio de educación MAT2004-0264