Cytochrome c 6-like protein as a putative donor of electrons to photosystem I in the cyanobacterium Nostoc sp. PCC 7119

Most organisms performing oxygenic photosynthesis contain either cytochrome c 6 or plastocyanin, or both, to transfer electrons from cytochrome b 6-f to photosystem I. Even though plastocyanin has superseded cytochrome c 6 along evolution, plants contain a modified cytochrome c 6, the so called cytochrome c 6A, whose function still remains unknown. In this article, we describe a second cytochrome c 6 (the so called cytochrome c 6-like protein), which is found in some cyanobacteria but is phylogenetically more related to plant cytochrome c 6A than to cyanobacterial cytochrome c 6. In this article, we conclude that the cytochrome c 6-like protein is a putative electron donor to photosystem I, but does play a role different to that of cytochrome c 6 and plastocyanin as it cannot accept electrons from cytochrome f. The existence of this third electron donor to PSI could explain why some cyanobacteria are able to grow photoautotrophically in the absence of both cytochrome c 6 and plastocyanin. In any way, the Cyt c 6-like protein from Nostoc sp. PCC 7119 would be potentially utilized for the biohydrogen production, using cell-free photosystem I catalytic nanoparticles.Dirección General de Investigación Científica y Técnica BFU2006-01361/BMCJunta de Andalucía PAI BIO022 BIO19

La historia y el cine: ¿unas amistades peligrosas?

En el pasado la historia y el cine se trataron con recelo e incluso con desprecio. En las dos últimas décadas, sin embargo, la historia del cine ha superado los meros criterios estéticos y ha emprendido la búsqueda de un método que la ha acercado bastante a los planteamientos de la historia sociocultural. Por su parte, la historia ha descubierto al cine no solamente como un recurso didáctico hoy accesible y lleno de posibilidades para recrear y explicar el pasado, sino como un auténtico documento necesario para investigar y comprender el siglo XX. Pero la imagen en movimiento presenta unas características propias que exigen un tratamiento distinto al de los documentos escritos, tanto por parte del profesor que la utiliza en sus clases como por el investigador que se sirve de ella para documentar su trabajo. En las páginas que siguen se realiza un balance historiográfico de la relación entre cine e historia y se ofrecen algunas reflexiones acerca de la evolución, y de las virtudes y limitaciones, de varias formas de entender esa relación: la historia del cine, el documental, el cine histórico, el cine como documento y el cine como agente de la histori

Religión o superstición. Un debate ilustrado en la España del siglo XVIII

The term “superstition” is a historical concept and, as such, it has changed throughout centuries and cultures. Always understood in relation to the idea of religion, it was defined as a fake or inappropriate religion, and in other occasions as the opposite end to impiety, while religion was relocated in the middle or ideal of virtue. Therefore, not only the discussion about religion, but also about superstition played a decisive role in the shaping of the particular Spanish way of thinking during the Enlightenment. The present work deals in depth with this crucial debate that culminated in the disagreement between official culture and popular culture or cultures.El término superstición es un concepto histórico y, como tal, ha ido variando a lo largo de los siglos y de las culturas. Entendido siempre en relación a la idea de religión, fue definido como una religión falsa o impropia, y otras veces como el extremo opuesto de la impiedad, pasando la religión a ocupar el centro o ideal de virtud. Si el debate sobre la religión jugó un papel decisivo en la configuración de un pensamiento ilustrado propiamente español, también lo tuvo, en consecuencia, el debate sobre la superstición. El presente trabajo profundiza en ese debate crucial que consumó el desencuentro entre la cultura oficial y la cultura o culturas populares

Emergent behaviors and scalability for multi-agent reinforcement learning-based pedestrian models

This paper analyzes the emergent behaviors of pedestrian groups that learn through the multiagent reinforcement learning model developed in our group. Five scenarios studied in the pedestrian model literature, and with different levels of complexity, were simulated in order to analyze the robustness and the scalability of the model. Firstly, a reduced group of agents must learn by interaction with the environment in each scenario. In this phase, each agent learns its own kinematic controller, that will drive it at a simulation time. Secondly, the number of simulated agents is increased, in each scenario where agents have previously learnt, to test the appearance of emergent macroscopic behaviors without additional learning. This strategy allows us to evaluate the robustness and the consistency and quality of the learned behaviors. For this purpose several tools from pedestrian dynamics, such as fundamental diagrams and density maps, are used. The results reveal that the developed model is capable of simulating human-like micro and macro pedestrian behaviors for the simulation scenarios studied, including those where the number of pedestrians has been scaled by one order of magnitude with respect to the situation learned.This work has been supported by grant TIN2015-65686-C5-1-R of Ministerio de Economía y Competitividad

El fracaso en la resolución de problemas de Física : una investigación orientada por nuevos supuestos

Cuestiona la explicación habitual del fracaso de los alumnos al resolver problemas. Se propone un modelo alternativo. Se presentan los resultados de la puesta en práctica del modelo con alumnos de 17 años, comparando con grupos de control, de igual y mayor edad

Partitioning approach for large wind farms: active power control for optimizing power reserve

© 2018 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works.Nowadays, large wind farms are expected to guarantee stability of the electrical grid contributing with ancillary services, such as frequency support. To this end, wind farm controllers must set the power generation of each turbine to compensate generation and demand imbalances. With the aim of optimizing primary frequency support, this paper proposes a partitioning approach to split large wind farms into several disjoint subsets of turbines according to the wake propagations through the wind farm. The partitioning problem is solved as a mixed-integer multi-objective optimization problem stated to maximize the strength of the coupling among the turbines due to the wake effect. Thus, no additional information sharing related to the wake propagations needs to be considered between the subsets. Different control tasks are assigned to the local controller of each subset, such that the total power generated meets the power demanded by the grid while the power reserve for enhancing primary frequency support is maximized. Finally, as an application of the proposed model, a decentralized wind farm control strategy is designed and compared with a centralized approach.Peer ReviewedPostprint (author's final draft

Introduction

Presentation of the volume 61.Presentació del volum 61.Presentación del volumen 61

Del Barroco a la Ilustración en una fiesta del Antiguo Régimen: el Corpus Christi

The long time evolution of the Corpus Christi feast lets distinguish two confronted forms for understand religiousness. The first one, coming from the Middle Age and in vogue during the baroque centuries, favors the mixture of cultured and popular, religious and profane elements; the second one, which imposes with the Enlightnment in the 18th century, clears the popular aspect from the feast and seizes it in te name of reason, interior religion and social control

Motivation, Discipline, and Academic Performance in Physical Education: A Holistic Approach From Achievement Goal and Self-Determination Theories.

The analysis of disciplined behaviors and academic performance in a school context has become one of the main concerns within the educational community. Physical Education is highlighted as a key subject to analyze students’ behavior. Researchers and Physical Education teachers are interested on the motivational processes that predict positive student outcomes in order to support them. Thus, the main purpose was to determine a predictive model of disciplined behaviors and academic performance in Physical Education students. The Achievement Goal Theory and Self-Determination Theory acted as the theoretical framework. A total of 919 Spanish secondary school students participated in the study. The studied variables were task-oriented motivational climate, basic psychological needs, autonomous motivation, disciplined behavior, and academic performance. Data collection included Spanish validated questionnaires. The Mplus statistical program was used to perform a structural equation model of prediction. It included antecedents (task-oriented climate), motivational processes (basic psychological needs and autonomous motivation), and consequences (disciplined behavior, Physical Education and overall students’ performance). The results revealed that positive outcomes (discipline and academic performance in Physical Education) were positively predicted by autonomous motivation; autonomous motivation was positively predicted by basic psychological needs and these, in addition, by the task-oriented climate. The results highlighted the importance of the task-oriented motivational climate and the mediating role of the basic psychological needs and autonomous motivation in order to generate these positive student outcomes in Physical Education. This study could be a useful resource for teachers, since it offers the motivational variables that lead students to achieve disciplined behaviors and academic performance in Physical Education. Intervention programs based on the results of the present study could be applied in Physical Education classes in order to obtain better behavioral as well as cognitive positive student outcomes.post-print512 K