On the Conditions that Justify Dynamic Reconfigurability in WDM-TDMA Optical Access Networks

[EN] In a passive optical network with a hybrid wavelength division multiplexing time division multiple-access scheme, implementing reconfigurable wavelength assignment is complex; hence the need to determine the conditions for which the capacity improvements justify requiring reconfigurability over adopting a more inexpensive fixed wavelength assignment. Fixed and reconfigurable approaches to wavelength assignment are modeled and evaluated under nonstationary traffic conditions. The performance improvement is obtained in terms of bit rate gain relative to the nominal bandwidth and depends on the number of wavelength channels as well as the magnitude of the load offered by the optical network units. In addition, frame delay and frame loss in relation to the bit rate performance are obtained for Pareto and exponentially distributed traffic. Simulations show that when introducing reconfigurability, typical peak bit rate gains with respect to the fixed case are 17%, and maxima of 175% are potentially possible when traffic demands are particularly uneven.This work was supported by the EC 7th Framework Program: Architectures for fLexible Photonic Home and Access networks (ALPHA), under contract ICT CP-IP 212 352, from the Generalitat of Valencia under contract ACOMP/2010/196. The authors thank the Performability Engineering Research Group (PERFORM) at the University of Illinois at Urbana-Champaign for developing the software tool Mobius.García Roger, D.; Artundo Martínez, I.; Ortega Tamarit, B. (2011). On the Conditions that Justify Dynamic Reconfigurability in WDM-TDMA Optical Access Networks. Journal of Optical Communications and Networking. 3(4):259-271. https://doi.org/10.1364/JOCN.3.000259S25927134A highly flexible and efficient passive optical network employing dynamic wavelength allocation. (2005). 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A comparison of dynamic bandwidth allocation for EPON, GPON, and next-generation TDM PON. IEEE Communications Magazine, 47(3), S40-S48. doi:10.1109/mcom.2009.4804388Papadimitriou, G. I., & Pomportsis, A. S. (1999). Self-adaptive TDMA protocols for WDM star networks: a learning-automata-based approach. IEEE Photonics Technology Letters, 11(10), 1322-1324. doi:10.1109/68.789731Linardakis, C., Leligou, H. C., Stavdas, A., & Angelopoulos, J. D. (2005). Using explicit reservations to arbitrate access to a metropolitan system of slotted interconnected rings combining TDMA and WDMA. Journal of Lightwave Technology, 23(4), 1576-1585. doi:10.1109/jlt.2005.844198Kanonakis, K., & Tomkos, I. (2010). Improving the efficiency of online upstream scheduling and wavelength assignment in hybrid WDM/TDMA EPON networks. IEEE Journal on Selected Areas in Communications, 28(6), 838-848. doi:10.1109/jsac.2010.100809McGarry, M. P., Reisslein, M., & Maier, M. (2006). WDM Ethernet passive optical networks. 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ON THE GEOGRAPHIC DISTRIBUTION OF NEMOGNATHA PLAUMANNI BORCHMANN, 1942 (COLEOPTERA: MELOIDAE): NEW RECORDS FROM VENEZUELA, WITH A 4500 KM RANGE EXTENSION

Nemognatha plaumanni Borchmann, 1942 (Coleoptera: Meloidae: Nemognathinae) was described from a single specimen found in Brazil, and since its description no additional information has been published on the species. During a field survey in Venezuela, we found one individual morphologically assignable to the species. In this note, we report and discuss this finding, which, together with the revision of the entomological collections of the Magyar Természettudományi Múzeum (Hungarian Natural History Museum, HNHM, Budapest, Hungary), the Natural History Museum (NHM, London, UK), and the Museo del Instituto de Zoología Agrícola (MIZA, Maracay, Venezuela), has led us to acknowledge the presence of the species in Venezuela, therefore extending the known distribution range of the species by more than 4500 km. We discuss the possibility that N. plaumanni might in fact correspond to a complex of cryptic species distributed over this vast range, an hypothesis that has to be tested with further field- and lab-work

Decreased Pain Perception by Unconscious Emotional Pictures

Pain perception arises from a complex interaction between a nociceptive stimulus and different emotional and cognitive factors, which appear to be mediated by both automatic and controlled systems. Previous evidence has shown that whereas conscious processing of unpleasant stimuli enhances pain perception, emotional influences on pain under unaware conditions are much less known. The aim of the present study was to investigate the modulation of pain perception by unconscious emotional pictures through an emotional masking paradigm. Two kinds of both somatosensory (painful and non-painful) and emotional stimulation (negative and neutral pictures) were employed. Fifty pain-free participants were asked to rate the perception of pain they were feeling in response to laser-induced somatosensory stimuli as faster as they can. Data from pain intensity and reaction times were measured. Statistical analyses revealed a significant effect for the interaction between pain and emotional stimulation, but surprisingly this relationship was opposite to expected. In particular, lower pain intensity scores and longer reaction times were found in response to negative images being strengthened this effect for painful stimulation. Present findings suggest a clear pain perception modulation by unconscious emotional contexts. Attentional capture mechanisms triggered by unaware negative stimulation could explain this phenomenon leading to a withdrawal of processing resources from pain

Application specific photonic integrated circuits through generic integration, a novel paradigm in photonics

[EN] This paper reviews our recent work on integrating photonic devices and sub-systems onto a single photonic chip, by means of generic integration.This work has been partially funded through the Spanish Plan Nacional de I+D+i 2008-2011 project ”Coupled Resonator Optical Waveguide eNgineering (CROWN)” grant no. TEC2008-06145/ TEC, by the Generalitat Valenciana through project PROMETEO/2008/092 and by the EC FP6 contract no. 004525 ePIXnet. J.D. Doménech acknowledges the FPI research grant BES-2009-018381.Muñoz Muñoz, P.; Doménech Gómez, JD.; Artundo Martínez, I.; Habib, C.; Leijtens, X.; De Vries, T.; Robbins, D.... (2011). Application specific photonic integrated circuits through generic integration, a novel paradigm in photonics. Waves. 3:58-64. http://hdl.handle.net/10251/57675S5864

Aprendizaje indagativo sobre los cambios físicos y químicos en la formación inicial del profesorado de secundaria

Inquiry-Based Science Education (IBSE) is an effective approach for learning science, but it demands a careful design of the activities and the role of the teacher to combine a conceptual, procedural and attitudinal learning. This article is linked to a proposal for the Chemistry Education subject of the Spanish Master’s in Secondary Education, which aims to train future high school teachers on these methodologies. The subject provides some first-hand opportunities to learn school chemistry by using IBSE. Therefore, this paper seeks to analyze the level of achievement by future teachers in solving open-ended problems about chemical change. The analysis of the individual written reports shows an improvement in the future teachers’ scientific competencies, which is especially relevant in the more conceptual dimensions, and less accused in those associated with the design of experimental solving strategies.La indagación conforma un enfoque beneficioso para el aprendizaje de las ciencias, pero demanda un diseño cuidadoso de las actividades y del rol del profesor para conjugar un aprendizaje conceptual, procedimental y actitudinal. El artículo se vincula a una propuesta para la asignatura de Didáctica de la Química del Máster en Formación del Profesorado, para formar al futuro profesorado sobre estas metodologías. Así, tras ofrecer vivencias personales sobre el aprendizaje por indagación, el trabajo busca examinar los logros de los estudiantes en la resolución de problemas abiertos sobre el cambio químico. A partir del análisis de los informes escritos individuales, se comprueba una mejoría en la competencia científica de los participantes, especialmente acusada en las dimensiones más conceptuales, y menor en las asociadas al diseño de estrategias experimentales de resolución

Pastores trashumantes del Neolítico antiguo en un entorno de alta montaña: secuencia crono-cultural de la Cova de Els Trocs (San Feliú de Veri, Huesca)

This paper presents the preliminary results of the excavation of the “Els Trocs’’ Cave, developed in the context of the research project “The pathways of the Neolithic”. The careful and detailed work of excavation and recording has revealed a complex stratigraphy in which, thanks to the radiocarbon dates on short-lived samples (cereal seeds, human bones and domestic animal remains), it has been possible to distinguish four different periods of occupation inside the cave. With this information and some preliminary analyses of part of the materials (pottery, flint and faunal remains), we have documented the presence of a human group in the mountain pastures of the axial Pyrennes, at a very early stage (beginning of the last third of the Vlth millennium cal. BC), with a transhumant pastoral economy. It was a fully neolithic population with clear evidences of the use of wheat and barley, despite they did not cultivate around the close environment of this cave, where complex burial rituals had been also documented.Este trabajo presenta los resultados preliminares obtenidos en la excavación de la Cova de Els Trocs, desarrollada dentro del proyecto de investigación "Los caminos del Neolítico". La minuciosa labor de excavación y de registro ha permitido establecer una compleja secuencia estratigráfica en la que, gracias a una veintena de dataciones radiocarbónicas sobre eventos singulares de vida corta (semillas de cereal, huesos humanos y fauna doméstica), se han podido diferenciar cuatro momentos de ocupación distintos de la cueva. Con estos datos y algunos análisis, también preliminares, de parte del registro (cerámica, sílex y restos faunísticos), se ha podido definir, en una época muy temprana (inicios del último tercio del VI milenio cal. BC.), la presencia en los pastos de montaña del Pirineo axial de un grupo humano que desarrolla una actividad pastoril trashumante. Una población plenamente neolitizada, que conoce el trigo y la cebada, aunque no los cultive en el entorno de la cueva, y que, a tenor de ciertas evidencias, practica complejos rituales tanatológicos

Tetrahydropyrazolo[1,5-a]Pyrimidine-3-Carboxamide and N-Benzyl-6′,7′-Dihydrospiro[Piperidine-4,4′-Thieno[3,2-c]Pyran] analogues with bactericidal efficacy against Mycobacterium tuberculosis targeting MmpL3

Mycobacterium tuberculosis is a major human pathogen and the causative agent for the pulmonary disease, tuberculosis (TB). Current treatment programs to combat TB are under threat due to the emergence of multi-drug and extensively-drug resistant TB. As part of our efforts towards the discovery of new anti-tubercular leads, a number of potent tetrahydropyrazolo[1,5-a]pyrimidine-3-ca​rboxamide(THPP) and N-benzyl-6′,7′-dihydrospiro[piperidine-4,​4′-thieno[3,2-c]pyran](Spiro) analogues were recently identified against Mycobacterium tuberculosis and Mycobacterium bovis BCG through a high-throughput whole-cell screening campaign. Herein, we describe the attractive in vitro and in vivo anti-tubercular profiles of both lead series. The generation of M. tuberculosis spontaneous mutants and subsequent whole genome sequencing of several resistant mutants identified single mutations in the essential mmpL3 gene. This ‘genetic phenotype’ was further confirmed by a ‘chemical phenotype’, whereby M. bovis BCG treated with both the THPP and Spiro series resulted in the accumulation of trehalose monomycolate. In vivo efficacy evaluation of two optimized THPP and Spiro leads showed how the compounds were able to reduce >2 logs bacterial cfu counts in the lungs of infected mice

Trisubstituted Pyrimidines as Efficacious and Fast-acting Antimalarials

In this paper we describe the optimization of a phenotypic hit against Plasmodium falciparum, based on a trisubstituted pyrimidine scaffold. This led to compounds with good pharmacokinetics and oral activity in a P. berghei mouse model of malaria. The most promising compound (13) showed a reduction in parasitemia of 96% when dosed at 30 mg/kg orally once a day for 4 days in the P. berghei mouse model of malaria. It also demonstrated a rapid rate of clearance of the erythrocytic stage of P. falciparum in the SCID mouse model with an ED90 of 11.7 mg/kg when dosed orally. Unfortunately, the compound is a potent inhibitor of cytochrome P450 enzymes, probably due to a 4-pyridyl substituent. Nevertheless, this is a lead molecule with a potentially useful antimalarial profile, which could either be further optimized or be used for target hunting

Metodología para la optimización de la maniobra de fondeo de cajones en infraestructuras marítimas

Los autores agradecen el soporte y la financiación del proyecto DOVICAIM. Proyecto del Programa estatal de Investigación, Desarrollo e Innovación Orientada a los Retos de la Sociedad 2014 (RTC-2014-3077-4

Genomic transformation and social organization during the Copper Age-Bronze Age transition in southern Iberia

The emerging Bronze Age (BA) of southeastern Iberia saw marked social changes. Late Copper Age (CA) settlements were abandoned in favor of hilltop sites, and collective graves were largely replaced by single or double burials with often distinctive grave goods indirectly reflecting a hierarchical social organization, as exemplified by the BA El Argar group. We explored this transition from a genomic viewpoint by tripling the amount of data available for this period. Concomitant with the rise of El Argar starting ∼2200 cal BCE, we observe a complete turnover of Y-chromosome lineages along with the arrival of steppe-related ancestry. This pattern is consistent with a founder effect in male lineages, supported by our finding that males shared more relatives at sites than females. However, simple two-source models do not find support in some El Argar groups, suggesting additional genetic contributions from the Mediterranean that could predate the BA.This work was supported by the Max Planck Society (V.V.-M. and W.H.); European Research Council (ERC) grant 771234—PALEoRIDER (W.H.); Spanish Ministry of Economy, Industry and Competitiveness project HAR2017-85962-P (C.O., C.R.-H., M.I.F., E.C.B., C.V.-F., V.L., R.M., and R.R.); AGAUR 2017SGR1044 (C.O., C.R.-H., M.I.F., E.C.B., C.V.-F., V.L., R.M., and R.R.); ICREA Academia program (R.R.); John Templeton Foundation grant 61220 (D.R.); and Paul Allen Family Foundation (D.R.). D.R. is an Investigator of the Howard Hughes Medical Institute