Anna Ajmátova, o tres traductores en busca de un autor

Análisis crítico de tres versiones castellanas de poemas de A. Ajmátova, desde diversos puntos de vista: lingüístico, estilístico, semántico y semióticoCritical analysis of three Spanish versions of the poems by A. Ajmátova, from different points of view: linguistic, stylistic, semantic and semioti

Los cuatro elementos naturales en la mitología precristiana rusa

Sin resume

Detection of replay attacks in CPSs using observer-based signature compensation

© 2019 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.This paper presents a replay attack detection method that addresses the performance loss of watermarking-based approaches. The proposed method injects a sinusoidal signal that affects a subset, chosen at random, of the system outputs. The presence of the signal in each one of the outputs is estimated by means of independent observers and its effect is compensated in the control loop. When a system output is affected by a replay attack, the loss of feedback of the associated observer destabilizes the signal estimation, leading to an exponential increase of the estimation error up to a threshold, above which the estimated signal compensation in the control loop is disabled. This event triggers the detection of a replay attack over the output corresponding to the disrupted observer. The effectiveness of the method is demonstrated using results obtained with a quadruple-tank system simulator.Peer ReviewedPostprint (author's final draft

Josep Antoni Balcells: la ambigüedad política de un catedrático de física-química

Josep Antoni Balcells was professor of physics and chemistry and head of the College of Pharmacy in Barcelona during its whole existence. He warmly and publicly welcomed the inauguration in 1820 of the constitutional period but later worked openly for its liquidation. This alternation of loyalties brought him difficulties first in the década ominosa and then during Espartero’s regency, that he affronted with some writings in his defence. Working in retrospect from the last of these, a little known booklet entitled Dionisio y Honorato, the authors have described the sequence of events

A virtual actuator approach for the secure control of networked LPV systems under pulse-width modulated DoS attacks

In this paper, we formulate and analyze the problem of secure control in the context of networked linear parameter varying (LPV) systems. We consider an energy-constrained, pulse-width modulated (PWM) jammer, which corrupts the control communication channel by performing a denial-of-service (DoS) attack. In particular, the malicious attacker is able to erase the data sent to one or more actuators. In order to achieve secure control, we propose a virtual actuator technique under the assumption that the behavior of the attacker has been identified. The main advantage brought by this technique is that the existing components in the control system can be maintained without need of retuning them, since the virtual actuator will perform a reconfiguration of the plant, hiding the attack from the controller point of view. Using Lyapunov-based results that take into account the possible behavior of the attacker, design conditions for calculating the virtual actuators gains are obtained. A numerical example is used to illustrate the proposed secure control strategy.Peer ReviewedPostprint (author's final draft

Susceptibility of different leukocyte cell types to Vaccinia virus infection

BACKGROUND: Vaccinia virus, the prototype member of the family Poxviridae, was used extensively in the past as the Smallpox vaccine, and is currently considered as a candidate vector for new recombinant vaccines. Vaccinia virus has a wide host range, and is known to infect cultures of a variety of cell lines of mammalian origin. However, little is known about the virus tropism in human leukocyte populations. We report here that various cell types within leukocyte populations have widely different susceptibility to infection with vaccinia virus. RESULTS: We have investigated the ability of vaccinia virus to infect human PBLs by using virus recombinants expressing green fluorescent protein (GFP), and monoclonal antibodies specific for PBL subpopulations. Flow cytometry allowed the identification of infected cells within the PBL mixture 1–5 hours after infection. Antibody labeling revealed that different cell populations had very different infection rates. Monocytes showed the highest percentage of infected cells, followed by B lymphocytes and NK cells. In contrast to those cell types, the rate of infection of T lymphocytes was low. Comparison of vaccinia virus strains WR and MVA showed that both strains infected efficiently the monocyte population, although producing different expression levels. Our results suggest that MVA was less efficient than WR in infecting NK cells and B lymphocytes. Overall, both WR and MVA consistently showed a strong preference for the infection of non-T cells. CONCLUSIONS: When infecting fresh human PBL preparations, vaccinia virus showed a strong bias towards the infection of monocytes, followed by B lymphocytes and NK cells. In contrast, very poor infection of T lymphocytes was detected. These finding may have important implications both in our understanding of poxvirus pathogenesis and in the development of improved smallpox vaccines

A reflexão no aprendizagem-serviço

El Aprendizaje-Servicio es una metodología cuya implantación en la educación superior exige vincular el servicio a la comunidad con el aprendizaje de contenidos académicos, competencias profesionales y valores cívicos. Uno de los mejores caminos para lograr tal conexión es implicar al alumnado en actividades de reflexión. Este tipo de actividad, además de contribuir a relacionar aprendizaje y servicio, multiplica los aprendizajes y da sentido personal y social a la experiencia de aprendizaje servicio. Para analizar el papel de la reflexión en las actividades de aprendizaje servicio se empieza presentando la idea de reflexión. A continuación se analiza una experiencia consolidada para corroborar tales ideas y profundizar en el papel de la reflexión en el aprendizaje servicio. El estudio del programa Amics i amigues de lectura de las facultades de Pedagogía y Formación del Profesorado de la Universidad de Barcelona y del Consorcio de Educación de Barcelona se aborda a través de una metodología etnográfica que nos acerca a los dinamismos de reflexión del programa: la acción tutorial, la escritura autorreflexiva y la reflexión entre iguales. Las conclusiones aportan ideas sobre cómo entender y mejorar los procesos de reflexión. Destacan aspectos como la conexión entre experiencia y reflexión, la necesidad de ofrecer múltiples dispositivos de reflexión, la conveniencia de ayudar a que sean los estudiantes quienes problematicen su experiencia y, finalmente, la incorporación de mediaciones –instrumentos y marcos conceptuales– como elemento clave de la actividad reflexiva de los participantes en las actividades de aprendizaje servicio.Service-learning is a method whose implementation in higher education requires linking community service with academic content learning, professional skills and civic values. One of the ways to achieve it is to have reflective activities. Furthermore, reflection is a means to enhance learning and to give personal and social meaning to the service learning proposals. To analyse the role of reflection in service learning activities, we will begin presenting the idea of reflection. Then, we will analyse a consolidated experience to substantiate such ideas and deepen the role of reflection in service learning. The study of the program Amics i amigues de lectura of the Faculties of Pedagogy and Teaching Learning of the University of Barcelona and Consorci d’Educació de Barcelona will be addressed through an ethnographic methodology by which we approach the dynamics of reflection of the program: the tutorial, reflective writing and reflection among equals. The findings provide insights on how to understand and improve the processes of reflection, highlight the connection between experience and reflection, the need for varied reflection devices, the convenience of helping the students to problematize their own experience and finally understand reflection as the incorporation of mediations -instruments and frameworks- in mental activity of the participants involved in service learning activities.O aprendizagem-serviço é uma metodologia cuja implantação na educação superior exige vincular o serviço à comunidade com a aprendizagem de conteúdos acadêmicos, competências profissionais e valores cívicos. Um dos melhores caminhos para lograr tal conexão é implicar o alunado em atividades de reflexão. Este tipo de atividade, ademais de contribuir para relacionar aprendizagem e serviço, multiplica as aprendizagens e dá sentido pessoal e social à experiência de aprendizagem-serviço. Para analisar o papel da reflexão nas atividades de aprendizagem-serviço se começa apresentando a ideia de reflexão. Na continuação se analisa uma experiência consolidada para corroborar tais ideias e aprofundar o papel da reflexão no aprendizagemserviço. O estudo do programa “Amics i amigues de lectura” das faculdades de Pedagogia e Formação do Professorado da Universidade de Barcelona e do Consórcio de Educação de Barcelona se aborda através de uma metodologia etnográfica que nos acerca aos dinamismos de reflexão do programa: a ação tutorial, a escritura auto-reflexiva e a reflexão entre iguais. As conclusões acrescentam ideias sobre como entender e melhorar os processos de reflexão. Destacam-se aspectos como a conexão entre experiência e reflexão, a necessidade de oferecer múltiplos dispositivos de reflexão, a conveniência de ajudar a que sejam os estudantes que problematizem sua experiência e, finalmente, a incorporação de mediações – instrumentos e marcos conceituais –, como elemento chave da atividade reflexiva dos participantes nas atividades de aprendizagemserviço

Erosion caused by propeller jets in a low energy harbour basin

This is an Accepted Manuscript of an article published by Taylor & Francis Group in Journal of Hydraulic Research on January, 2017, available online at: http://www.tandfonline.com/10.1080/00221686.2016.1252801Field data of a harbour basin are compared with analytical formulations for predicting maximum scouring depth due to propeller jets. Spatial data analysis of seven-year biannual bathymetries quantifies the evolution of the scouring hole along with the sedimentation process within a harbour basin. The maximum scouring depth is found to be of the order of the propeller diameter with a maximum scouring rate within the first six months of docking manoeuvring. Three of the analysed expressions yielded realistic results while observed discrepancies between the theoretical predictions and field data are related to scaling factors. The outcomes of this analysis can be extrapolated to other harbours to improve their management. The obtained results highlight the importance of field data in developing combined physical and numerical models.Peer ReviewedPostprint (author's final draft