Paradoxical Interplay of Viral and Cellular Functions

Some cellular editing functions can restrict the replication of some viruses but contribute to completion of the life cycle of others. A recent study has identified an isoform of the adenosine deaminase acting on RNA type 1 (ADAR 1) as required for embryogenesis, and as a restriction factor for a number of important RNA virus pathogens [1]. The dual implication of key cellular functions in the innate immunity against viruses, or, paradoxically, as mediators of virus replication is interpreted in the light of the concept of virus-host coevolution and tinkering proposed for general evolution by François Jacob decades ago

Indirect Methods for Robot Skill Learning

Robot learning algorithms are appealing alternatives for acquiring rational robotic behaviors from data collected during the execution of tasks. Furthermore, most robot learning techniques are stated as isolated stages and focused on directly obtaining rational policies as a result of optimizing only performance measures of single tasks. However, formulating robotic skill acquisition processes in such a way have some disadvantages. For example, if the same skill has to be learned by different robots, independent learning processes should be carried out for acquiring exclusive policies for each robot. Similarly, if a robot has to learn diverse skills, the robot should acquire the policy for each task in separate learning processes, in a sequential order and commonly starting from scratch. In the same way, formulating the learning process in terms of only the performance measure, makes robots to unintentionally avoid situations that should not be repeated, but without any mechanism that captures the necessity of not repeating those wrong behaviors. In contrast, humans and other animals exploit their experience not only for improving the performance of the task they are currently executing, but for constructing indirectly multiple models to help them with that particular task and to generalize to new problems. Accordingly, the models and algorithms proposed in this thesis seek to be more data efficient and extract more information from the interaction data that is collected either from expert\u2019s demonstrations or the robot\u2019s own experience. The first approach encodes robotic skills with shared latent variable models, obtaining latent representations that can be transferred from one robot to others, therefore avoiding to learn the same task from scratch. The second approach learns complex rational policies by representing them as hierarchical models that can perform multiple concurrent tasks, and whose components are learned in the same learning process, instead of separate processes. Finally, the third approach uses the interaction data for learning two alternative and antagonistic policies that capture what to and not to do, and which influence the learning process in addition to the performance measure defined for the task

Neutron capture on ^{205}Tl: depicting the abundance pattern of lead isotopes in s-process nucleosynthesis

Proposal: Neutron capture on 205Tl: depicting the abundance pattern of lead isotopes in s-process nucleosynthesisWe propose to use the TOF technique to measure the neutron capture cross section of 205Tl(n,gamma) over the full energy range of stellar interest. An accurate measurement of this cross section is needed for a complete and consistent understanding of the s-process nucleosynthesis of the heaviest nuclei which are produced in low-mass and low metallicity AGB-stars. The only previous TOF measurement has yield only a partial information, insufficient for a reliable analysis of the complex branching pattern around 205Pb and 205Tl. Furthermore, there is also a discrepancy of 40% between the two previous activation measurements made at kT=24 keV. The cross section of 205Tl(n,gamma) is particularly relevant because it affects the equilibrium that is established in some stellar conditions between the 205Tl -> 205Pb bound-state Beta-decay and the 205Pb -> 205Tl E.C. decay. This effect induces a complex interplay which influences the final s-process abundance of both nuclei. We propose to measure accurately and with high resolution the 205Tl(n,gamma) cross section by using a set of four C6D6 detectors in combination with the pulsed neutron-source of CERN n_TOF.Preprin

Ética

Departament de Filosofia i Sociologia. Codi assignatura: HU1016, HP101

Clonality and intracellular polyploidy in virus evolution and pathogenesis

In the present article we examine clonality in virus evolution. Most viruses retain an active recombination machinery as a potential means to initiate new levels of genetic exploration that go beyond those attainable solely by point mutations. However, despite abundant recombination that may be linked to molecular events essential for genome replication, herein we provide evidence that generation of recombinants with altered biological properties is not essential for the completion of the replication cycles of viruses, and that viral lineages (near-clades) can be defined. We distinguish mechanistically active but inconsequential recombination from evolutionarily relevant recombination, illustrated by episodes in the field and during experimental evolution. In the field, recombination has been at the origin of new viral pathogens, and has conferred fitness advantages to some viruses once the parental viruses have attained a sufficient degree of diversification by point mutations. In the laboratory, recombination mediated a salient genome segmentation of foot-and-mouth disease virus, an important animal pathogen whose genome in nature has always been characterized as unsegmented. We propose a model of continuous mutation and recombination, with punctuated, biologically relevant recombination events for the survival of viruses, both as disease agents and as promoters of cellular evolution. Thus, clonality is the standard evolutionary mode for viruses because recombination is largely inconsequential, since the decisive events for virus replication and survival are not dependent on the exchange of genetic material and formation of recombinant (mosaic) genomes.Work in Madrid is supported by Grants BFU-2011-23604 and P2013/ABI-2906 (PLATESA from Comunidad Autónoma de Madrid) and Fundación R. Areces; Centro de Investigación en Red de Enfermedades Hepáticas y Digestivas is funded by Instituto de Salud Carlos III; E.M. is supported by a fellowship from Ministerio de Economía y Competitividad; and C.P. is supported by theMiguel Servet program of the FIS Instituto de Salud Carlos III (CP14/00121).Peer Reviewe

Fault management based on machine learning

© 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.Machine Learning (ML) brings many benefits for network operation. In this paper, basic ML concepts and its integration into existing network control and management planes are reviewed. Case studies covering fault management are illustrated.Peer ReviewedPostprint (author's final draft

Ultra-deep pyrosequencing detects conserved genomic sites and quantifies linkage of drug-resistant amino acid changes in the hepatitis B virus genome

Background: Selection of amino acid substitutions associated with resistance to nucleos(t)ide-analog (NA) therapy in the hepatitis B virus (HBV) reverse transcriptase (RT) and their combination in a single viral genome complicates treatment of chronic HBV infection and may affect the overlapping surface coding region. In this study, the variability of an overlapping polymerase-surface region, critical for NA resistance, is investigated before treatment and under antiviral therapy, with assessment of NA-resistant amino acid changes simultaneously occurring in the same genome (linkage analysis) and their influence on the surface coding region. Methodology/Principal Findings: Serum samples obtained from chronic HBV-infected patients at pre-treatment and during sequential NA treatment with lamivudine, adefovir, and entecavir were analyzed by ultra-deep pyrosequencing (UDPS) using the GS-FLX platform (454 Life Sciences-Roche). The pre-treatment HBV quasispecies was not enriched with NA-resistant substitutions. The frequencies of this type of substitutions at pre-treatment did not predict the frequencies observed during lamivudine treatment. On linkage analysis of the RT region studied, NA-resistant HBV variants (except for rtA181T) were present in combinations of amino acid substitutions that increased in complexity after viral breakthrough to entecavir, at which time the combined variant rtL180M-S202G-M204V-V207I predominated. In the overlapping surface region, NA-resistant substitutions caused selection of stop codons in a significant percentage of sequences both at pre-treatment and during sequential treatment; the rtA181T substitution, related to sW172stop, predominated during treatment with lamivudine and adefovir. A highly conserved RT residue (rtL155), even more conserved than the essential residues in the RT catalytic motif YMDD, was identified in all samples. Conclusions: UDPS methodology enabled quantification of HBV quasispecies variants, even those harboring complex combinations of amino acid changes. The high percentage of potentially defective genomes, especially in the surface region, suggests effective trans-complementation of these variants. © 2012 Rodriguez-Frías et al.Centro para el Desarrollo Tecnológico Industrial; Ministry of Economy and CompetitivenessPeer Reviewe

La responsabilidad Social Empresarial (RSE) en Europa: la apuesta por un nuevo modelo de empresa. Una revisión crítica desde la ética empresarial

El presente artículo tiene un doble objetivo. Por una parte, poner de manifiesto el desarrollo del discurso europeo respecto a la necesidad de asunción de valores y principios sociales y medioambientales en la gestión y dirección de las empresas con la finalidad de alcanzar altas cotas de competitividad y de cohesión social. Por otra parte, ofrecer un modelo de Responsabilidad Social Empresarial (RSE) fundamentado en la teoría ético-discursiva que permite delimitar la definición y el alcance de la responsabilidad de las empresas, así como aportar algunas orientaciones prácticas acerca de cómo opera este modelo en la práctica.The purpose of the present article is twofold. On one hand, it expounds the development of the European discourse on the need to incorporate social and environmental values and principles into business management in order to reach high levels of competitiveness and social cohesion. On the other hand, the article offers a model of Corporate Social Responsibility (CSR) based on discourse ethics theory that allows us to set boundaries to the definition and scope of the responsibilities of businesses, and to contribute some practical orientations on how this model operates in practice

Flexible fog computing and telecom architecture for 5G networks

We review a novel, secure, highly distributed and ultra-dense fog computing infrastructure, which can be allocated at the extreme edge of a wired/wireless network for a Telecom Operator to provide multiple unified, cost-effective and new 5G services, such as Network Function Virtualization (NFV), Mobile Edge Computing (MEC), and services for third parties (e.g., smart cities, vertical industries or Internet of Things (IoT)). The distributed and programmable fog technologies are expected to strengthen the position of the Mobile Network and cloud markets; key benefits are the dynamic deployment of new distributed low-latency services. The architecture consists of three main building blocks: a) a scalable node, that is seamlessly integrated in the Telecom infrastructure; b) a controller, focused on service assurance, that is integrated in the management and orchestration architecture of the Telecom operator; and c) services running on top of the Telecom infrastructure.Peer ReviewedPostprint (author's final draft