171 research outputs found
Communications for cooperation: the RoboCup 4-legged passing challenge
Communications are the basis for the collaborative
activities in the TeamChaos 4-legged team. In this paper we
present the communications architecture developed both to let
teammates communicate, and to easy the debugging of robot
behaviors from external computers. Details of its implementation
on the aiBo robots are also given. Using this infrastructure we
describe a protocol for role exchange named Switch! that we have
created. We also describe the use of both the communication
architecture, and the Switch! protocol in the passing challenge
of the 2006 edition of the RoboCu
Predicting the accuracy of multiple sequence alignment algorithms by using computational intelligent techniques
Multiple sequence alignments (MSAs) have become one of the most studied approaches in bioinformatics to perform other outstanding tasks such as structure prediction, biological function analysis or next-generation sequencing. However, current MSA algorithms do not always provide consistent solutions, since alignments become increasingly difficult when dealing with low similarity sequences. As widely known, these algorithms directly depend on specific features of the sequences, causing relevant influence on the alignment accuracy. Many MSA tools have been recently designed but it is not possible to know in advance which one is the most suitable for a particular set of sequences. In this work, we analyze some of the most used algorithms presented in the bibliography and their dependences on several features. A novel intelligent algorithm based on least square support vector machine is then developed to predict how accurate each alignment could be, depending on its analyzed features. This algorithm is performed with a dataset of 2180 MSAs. The proposed system first estimates the accuracy of possible alignments. The most promising methodologies are then selected in order to align each set of sequences. Since only one selected algorithm is run, the computational time is not excessively increased
Demonstration of near infrared gas sensing using gold nanodisks on functionalized silicon
This paper was published in OPTICS EXPRESS and is made available as an electronic reprint with the permission of OSA. The paper can be found at the following URL on the OSA website: http://dx.doi.org/10.1364/OE.19.007664. Systematic or multiple reproduction or distribution to multiple locations via electronic or other means is prohibited and is subject to penalties under law[EN] In this work, we demonstrate experimentally the use of an array of gold nanodisks on functionalized silicon for chemosensing purposes. The metallic nanostructures are designed to display a very strong plasmonic resonance in the infrared regime, which results in highly sensitive sensing. Unlike usual experiments which are based on the functionalization of the metal surface, we functionalized here the silicon substrate. This silicon surface was modified chemically by buildup of an organosilane self-assembled monolayer (SAM) containing isocyanate as functional group. These groups allow for an easy surface regeneration by simple heating, thanks to the thermally reversible interaction isocyanate-analyte, which allows the cyclic use of the sensor. The technique showed a high sensitivity to surface binding events in gas and allowed the surface regeneration by heating of the sensor at 150°C. A relative wavelength shift ¿¿max/¿0 = 0.027 was obtained when the saturation level was reached. © 2011 Optical Society of America.Financial support by the Spanish MICINN under contracts CONSOLIDER EMET (CSD2008-00066) and TEC2008-06871-C02-02 and European Commission FP7 under the FET-Open project TAILPHOX 233833 is gratefully acknowledged.Rodríguez Cantó, PJ.; Martínez Marco, ML.; Rodríguez Fortuño, FJ.; Tomás Navarro, B.; Ortuño Molinero, R.; Peransi Llopis, SM.; Martínez Abietar, AJ. (2011). Demonstration of near infrared gas sensing using gold nanodisks on functionalized silicon. Optics Express. 19(8):7664-7672. https://doi.org/10.1364/OE.19.00766476647672198Barnes, W. L., Dereux, A., & Ebbesen, T. W. (2003). Surface plasmon subwavelength optics. Nature, 424(6950), 824-830. doi:10.1038/nature01937Maier, S. A., Brongersma, M. L., Kik, P. G., Meltzer, S., Requicha, A. A. G., & Atwater, H. A. (2001). Plasmonics-A Route to Nanoscale Optical Devices. Advanced Materials, 13(19), 1501-1505. doi:10.1002/1521-4095(200110)13:193.0.co;2-zLink, S., & El-Sayed, M. A. (2003). OPTICALPROPERTIES ANDULTRAFASTDYNAMICS OFMETALLICNANOCRYSTALS. Annual Review of Physical Chemistry, 54(1), 331-366. doi:10.1146/annurev.physchem.54.011002.103759Willets, K. A., & Van Duyne, R. P. (2007). Localized Surface Plasmon Resonance Spectroscopy and Sensing. Annual Review of Physical Chemistry, 58(1), 267-297. doi:10.1146/annurev.physchem.58.032806.104607Anker, J. N., Hall, W. P., Lyandres, O., Shah, N. C., Zhao, J., & Van Duyne, R. P. (2008). Biosensing with plasmonic nanosensors. Nature Materials, 7(6), 442-453. doi:10.1038/nmat2162Zhao, J., Zhang, X., Yonzon, C. R., Haes, A. J., & Van Duyne, R. P. (2006). Localized surface plasmon resonance biosensors. Nanomedicine, 1(2), 219-228. doi:10.2217/17435889.1.2.219SHANKARAN, D., GOBI, K., & MIURA, N. (2007). Recent advancements in surface plasmon resonance immunosensors for detection of small molecules of biomedical, food and environmental interest. Sensors and Actuators B: Chemical, 121(1), 158-177. doi:10.1016/j.snb.2006.09.014Miura, N., Ogata, K., Sakai, G., Uda, T., & Yamazoe, N. (1997). Detection of Morphine in ppb Range by Using SPR (Surface- Plasmon-Resonance) Immunosensor. Chemistry Letters, 26(8), 713-714. doi:10.1246/cl.1997.713Shankaran, D. R., Matsumoto, K., Toko, K., & Miura, N. (2006). Development and comparison of two immunoassays for the detection of 2,4,6-trinitrotoluene (TNT) based on surface plasmon resonance. Sensors and Actuators B: Chemical, 114(1), 71-79. doi:10.1016/j.snb.2005.04.013Cosnier, S. (1999). Biomolecule immobilization on electrode surfaces by entrapment or attachment to electrochemically polymerized films. A review. Biosensors and Bioelectronics, 14(5), 443-456. doi:10.1016/s0956-5663(99)00024-xLee, J. W., Sim, S. J., Cho, S. M., & Lee, J. (2005). Characterization of a self-assembled monolayer of thiol on a gold surface and the fabrication of a biosensor chip based on surface plasmon resonance for detecting anti-GAD antibody. Biosensors and Bioelectronics, 20(7), 1422-1427. doi:10.1016/j.bios.2004.04.017Mark, S. S., Sandhyarani, N., Zhu, C., Campagnolo, C., & Batt, C. A. (2004). Dendrimer-Functionalized Self-Assembled Monolayers as a Surface Plasmon Resonance Sensor Surface. Langmuir, 20(16), 6808-6817. doi:10.1021/la0495276Kato, K., Dooling, C. M., Shinbo, K., Richardson, T. H., Kaneko, F., Tregonning, R., … Hunter, C. A. (2002). Surface plasmon resonance properties and gas response in porphyrin Langmuir–Blodgett films. Colloids and Surfaces A: Physicochemical and Engineering Aspects, 198-200, 811-816. doi:10.1016/s0927-7757(01)01006-8Senaratne, W., Andruzzi, L., & Ober, C. K. (2005). Self-Assembled Monolayers and Polymer Brushes in Biotechnology: Current Applications and Future Perspectives. Biomacromolecules, 6(5), 2427-2448. doi:10.1021/bm050180aStewart, M. E., Anderton, C. R., Thompson, L. B., Maria, J., Gray, S. K., Rogers, J. A., & Nuzzo, R. G. (2008). Nanostructured Plasmonic Sensors. Chemical Reviews, 108(2), 494-521. doi:10.1021/cr068126nYin, L., Liu, Y., Ke, Z., & Yin, J. (2009). Preparation of a blocked isocyanate compound and its grafting onto styrene-b-(ethylene-co-1-butene)-b-styrene triblock copolymer. European Polymer Journal, 45(1), 191-198. doi:10.1016/j.eurpolymj.2008.10.016Suyama, K., Iriyama, H., Shirai, M., & Tsunooka, M. (2001). Curing Systems Using Photolysis of Carbomoyloxyimino Groups and Themally Regenerated Isocyanate Groups. Journal of Photopolymer Science and Technology, 14(2), 155-158. doi:10.2494/photopolymer.14.155Patskovsky, S., Kabashin, A. V., Meunier, M., & Luong, J. H. T. (2004). Near-infrared surface plasmon resonance sensing on a silicon platform. Sensors and Actuators B: Chemical, 97(2-3), 409-414. doi:10.1016/j.snb.2003.09.023Shelton, D. J., Peters, D. W., Sinclair, M. B., Brener, I., Warne, L. K., Basilio, L. I., … Boreman, G. D. (2010). Effect of thin silicon dioxide layers on resonant frequency in infrared metamaterials. Optics Express, 18(2), 1085. doi:10.1364/oe.18.001085Bhalla, V., Carrara, S., Stagni, C., & Samorì, B. (2010). Chip cleaning and regeneration for electrochemical sensor arrays. Thin Solid Films, 518(12), 3360-3366. doi:10.1016/j.tsf.2009.10.022Malinsky, M. D., Kelly, K. L., Schatz, G. C., & Van Duyne, R. P. (2001). Chain Length Dependence and Sensing Capabilities of the Localized Surface Plasmon Resonance of Silver Nanoparticles Chemically Modified with Alkanethiol Self-Assembled Monolayers. Journal of the American Chemical Society, 123(7), 1471-1482. doi:10.1021/ja003312aSpencer, M. J. S., & Nyberg, G. L. (2004). Adsorption of silane and methylsilane on gold surfaces. Surface Science, 573(2), 151-168. doi:10.1016/j.susc.2004.08.043Gradess, R., Abargues, R., Habbou, A., Canet-Ferrer, J., Pedrueza, E., Russell, A., … Martínez-Pastor, J. P. (2009). Localized surface plasmon resonance sensor based on Ag-PVA nanocomposite thin films. Journal of Materials Chemistry, 19(48), 9233. doi:10.1039/b910020bBrolo, A. G., Gordon, R., Leathem, B., & Kavanagh, K. L. (2004). Surface Plasmon Sensor Based on the Enhanced Light Transmission through Arrays of Nanoholes in Gold Films. Langmuir, 20(12), 4813-4815. doi:10.1021/la0493621MAURIZ, E., CALLE, A., MONTOYA, A., & LECHUGA, L. (2006). Determination of environmental organic pollutants with a portable optical immunosensor. Talanta, 69(2), 359-364. doi:10.1016/j.talanta.2005.09.049Yu, Q., Chen, S., Taylor, A. D., Homola, J., Hock, B., & Jiang, S. (2005). Detection of low-molecular-weight domoic acid using surface plasmon resonance sensor. Sensors and Actuators B: Chemical, 107(1), 193-201. doi:10.1016/j.snb.2004.10.064Cui, X. (2003). Real-time immunoassay of ferritin using surface plasmon resonance biosensor. Talanta, 60(1), 53-61. doi:10.1016/s0039-9140(03)00043-
High order standing-wave plasmon resonances in silver u-shaped nanowires
Optical measurements of the transmission spectra through nanofabricated planar arrays of silver u-shaped nanowires on a silicon substrate resonating at infrared frequencies are performed. Good agreement with the numerically simulated surface plasmon standing wave resonances supported by the structures is found. Such resonances exhibit field enhancement and are able to provide magnetic and electric responses when used as the unit cell of a metamaterial. The magnetic excitation of the resonators using oblique incidence is shown to be drastically reduced by the existence of a high index substrate such as silicon. © 2012 American Institute of Physics.We acknowledge financial support from the Spanish MICINN under Contracts CONSOLIDER EMET CSD2008-00066 and TEC2011-28664-C02-02. F. J. Rodriguez-Fortuno acknowledges financial support from Grant FPI of GV.Rodríguez Fortuño, FJ.; Ortuño Molinero, R.; García Meca, C.; Martí Sendra, J.; Martínez Abietar, AJ. (2012). High order standing-wave plasmon resonances in silver u-shaped nanowires. Journal of Applied Physics. 112:103104-103104. https://doi.org/10.1063/1.4759444S103104103104112Barnes, W. L., Dereux, A., & Ebbesen, T. W. (2003). Surface plasmon subwavelength optics. Nature, 424(6950), 824-830. doi:10.1038/nature01937Anker, J. N., Hall, W. P., Lyandres, O., Shah, N. C., Zhao, J., & Van Duyne, R. P. (2008). Biosensing with plasmonic nanosensors. Nature Materials, 7(6), 442-453. doi:10.1038/nmat2162Kawata, S., Inouye, Y., & Verma, P. (2009). Plasmonics for near-field nano-imaging and superlensing. Nature Photonics, 3(7), 388-394. doi:10.1038/nphoton.2009.111Willets, K. A., & Van Duyne, R. P. (2007). Localized Surface Plasmon Resonance Spectroscopy and Sensing. Annual Review of Physical Chemistry, 58(1), 267-297. doi:10.1146/annurev.physchem.58.032806.104607Enkrich, C., Wegener, M., Linden, S., Burger, S., Zschiedrich, L., Schmidt, F., … Soukoulis, C. M. (2005). Magnetic Metamaterials at Telecommunication and Visible Frequencies. Physical Review Letters, 95(20). doi:10.1103/physrevlett.95.203901Pendry, J. B. (2006). Controlling Electromagnetic Fields. Science, 312(5781), 1780-1782. doi:10.1126/science.1125907Pendry, J. B. (2000). Negative Refraction Makes a Perfect Lens. Physical Review Letters, 85(18), 3966-3969. doi:10.1103/physrevlett.85.3966Martínez, A., García-Meca, C., Ortuño, R., Rodríguez-Fortuño, F. J., & Martí, J. (2009). Metamaterials for optical security. Applied Physics Letters, 94(25), 251106. doi:10.1063/1.3152794Rodríguez-Fortuño, F. J., García-Meca, C., Ortuño, R., Martí, J., & Martínez, A. (2009). Modeling high-order plasmon resonances of a U-shaped nanowire used to build a negative-index metamaterial. Physical Review B, 79(7). doi:10.1103/physrevb.79.075103Boudarham, G., Feth, N., Myroshnychenko, V., Linden, S., García de Abajo, J., Wegener, M., & Kociak, M. (2010). Spectral Imaging of Individual Split-Ring Resonators. Physical Review Letters, 105(25). doi:10.1103/physrevlett.105.255501Johnson, N. P., Khokhar, A. Z., Chong, H. M. H., De La Rue, R. M., & McMeekin, S. (2006). Characterisation at infrared wavelengths of metamaterials formed by thin-film metallic split-ring resonator arrays on silicon. Electronics Letters, 42(19), 1117. doi:10.1049/el:20062212Rockstuhl, C., Zentgraf, T., Guo, H., Liu, N., Etrich, C., Loa, I., … Giessen, H. (2006). Resonances of split-ring resonator metamaterials in the near infrared. Applied Physics B, 84(1-2), 219-227. doi:10.1007/s00340-006-2205-2Rockstuhl, C., Lederer, F., Etrich, C., Zentgraf, T., Kuhl, J., & Giessen, H. (2006). On the reinterpretation of resonances in split-ring-resonators at normal incidence. Optics Express, 14(19), 8827. doi:10.1364/oe.14.008827Sheridan, A. K., Clark, A. W., Glidle, A., Cooper, J. M., & Cumming, D. R. S. (2007). Multiple plasmon resonances from gold nanostructures. Applied Physics Letters, 90(14), 143105. doi:10.1063/1.2719161Chen, C.-Y., Wu, S.-C., & Yen, T.-J. (2008). Experimental verification of standing-wave plasmonic resonances in split-ring resonators. Applied Physics Letters, 93(3), 034110. doi:10.1063/1.2957978Pfeiffer, C. A., Economou, E. N., & Ngai, K. L. (1974). Surface polaritons in a circularly cylindrical interface: Surface plasmons. Physical Review B, 10(8), 3038-3051. doi:10.1103/physrevb.10.3038Schider, G., Krenn, J. R., Hohenau, A., Ditlbacher, H., Leitner, A., Aussenegg, F. R., … Boreman, G. (2003). Plasmon dispersion relation of Au and Ag nanowires. Physical Review B, 68(15). doi:10.1103/physrevb.68.155427Neubrech, F., Kolb, T., Lovrincic, R., Fahsold, G., Pucci, A., Aizpurua, J., … Karim, S. (2006). Resonances of individual metal nanowires in the infrared. Applied Physics Letters, 89(25), 253104. doi:10.1063/1.2405873Zhou, J., Koschny, T., Kafesaki, M., Economou, E. N., Pendry, J. B., & Soukoulis, C. M. (2005). Saturation of the Magnetic Response of Split-Ring Resonators at Optical Frequencies. Physical Review Letters, 95(22). doi:10.1103/physrevlett.95.223902Delgado, V., Sydoruk, O., Tatartschuk, E., Marqués, R., Freire, M. J., & Jelinek, L. (2009). Analytical circuit model for split ring resonators in the far infrared and optical frequency range. Metamaterials, 3(2), 57-62. doi:10.1016/j.metmat.2009.03.00
Holographic Characteristics of Photopolymers Containing Different Mixtures of Nematic Liquid Crystals
A holographic polymer dispersed liquid crystal (HPDLC) is used to record holographic diffraction gratings. Several mixtures of nematic liquid crystals (LC) are used as components of the HPDLC to evaluate their influence in static and dynamic basic properties. The diffraction efficiency obtained in the reconstruction of the holograms is evaluated to compare the influence of the different LC. Additionally, the samples are exposed to a variable electric field and the diffracted light intensity as a function of the applied voltage is measured to evaluate the influence of the LC. The results obtained show significant differences depending on the LC incorporated to the photopolymer.This work was supported by ‘Ministerio de Ciencia, Innovación y Universidades’ (before ‘Ministerio de Economía, Industria y Competitividad’), Spain, under projects FIS2017-82919-R (MINECO/AEI/FEDER, UE) and FIS2015-66570-P (MINECO/FEDER), and by Generalitat Valenciana, Spain, under project PROMETEO II/2015/015
Los Recursos Educativos Abiertos adaptados a estilos de aprendizaje en la enseñanza de competencias digitales en educación superior
Los Recursos Educativos Abiertos (REA) son considerados vectores significativos de cambio por su flexibilidad y transversalidad en todos los niveles educativos, permitiendo además la personalización basada en estilos de aprendizaje. En este estudio se diseñaron cuatro REA según la teoría de Honey y Mumford (1986) (Activo-Reflexivo-Teórico-Pragmático), para la competencia en gestión de información digital. Mediante una actividad formativa diseñada para la investigación se identificaron los Estilos de Aprendizaje de estudiantes universitarios (N=394) con el cuestionario CHAEA (Alonso, 1992) y se asignaron los REA, uno correspondiente a su estilo y otro,al contrario, al finalizar los estudiantes valoraron el interés yla adecuación de los recursos analizados. Entre los resultados se observa que tanto en la valoración del interés como de la adecuación (estructura, tiempo, instrucciones y objetivo) las puntuaciones son más elevadas cuando el REA se adapta a su estilo, excepto en la percepción del tiempo empleado por los estudiantes de estilo Activoy Teórico. Se concluye que la adaptación a estilos permite la personalización del aprendizaje porque aumenta el interés y mejora la asimilación por parte de los estudiantes. Alser recursos de acceso libre, se posibilita que sean reutilizados, de acuerdo con estándares e-Learning, para la formación en competencias.Open Educational Resources (OER) are considered significant vectors of change due to their flexibility and transversality at all educational levels, also allowing customization based on learning styles. Four OER were designed in this study, according to the theory of Honey and Mumford (1986) (Active-Reflective-Theoretical-Pragmatic), for thedigital information managementcompetence. Through a training activity designed for research, the Learning Styles of university students (N=394) were identified with the CHAEA questionnaire (Alonso, 1992) and the OERs were assigned, one corresponding to their style and another to the contrary, at the end the students assessedthe perceived interest and adequacy of the analyzed resources. Among the results, it is observed that eitherthe assessment of interest and the adequacy (structure, time, instructions,and objective) of the scores werehigher when the OER adapts to their style, except in the perception of the time used by the students of Active and Theoretical style. It is concluded that the adaptation to styles facilitates thepersonalization of learning because it increases its interest and improves assimilation by students. Being free access resources, it is possible for them to be reused, in accordance with e-Learning standards, especially for skillstraining
Assessing the Impact of SARS-CoV-2 Lineages and Mutations on Patient Survival
Objectives: More than two years into the COVID-19 pandemic, SARS-CoV-2 still remains a
global public health problem. Successive waves of infection have produced new SARS-CoV-2 variants
with new mutations for which the impact on COVID-19 severity and patient survival is uncertain.
Methods: A total of 764 SARS-CoV-2 genomes, sequenced from COVID-19 patients, hospitalized from
19th February 2020 to 30 April 2021, along with their clinical data, were used for survival analysis.
Results: A significant association of B.1.1.7, the alpha lineage, with patient mortality (log hazard ratio
(LHR) = 0.51, C.I. = [0.14,0.88]) was found upon adjustment by all the covariates known to affect
COVID-19 prognosis. Moreover, survival analysis of mutations in the SARS-CoV-2 genome revealed
27 of them were significantly associated with higher mortality of patients. Most of these mutations
were located in the genes coding for the S, ORF8, and N proteins. Conclusions: This study illustrates
how a combination of genomic and clinical data can provide solid evidence for the impact of viral
lineage on patient survival.Ministry of Science and Innovation, Spain (MICINN)
Spanish Government PID2020117979RB-I00Instituto de Salud Carlos III
European Commission
European Commission IMP/00019Junta de Andalucia COVID-0012-2020
PS-2020-342European Social Fund (ESF) 871075Carlos Loucera PAIDI2020-DOC_0035
The Decrease in Auxin Polar Transport Down the Lupin Hypocotyl Could Produce the Indole-3-Acetic Acid Distribution Responsible for the Elongation Growth Pattern
La tasa turística: un análisis sobre su idoneidad en la Comunitat Valenciana
La tasa turística es un tipo de tributo establecido en muchos enclaves a lo ancho del mundo, caracterizados, por lo general, por su gran atractivo turístico, que los convierte en destinos únicos, irrepetibles, con singulares atractivos para el turista. Esta tasa grava, generalmente, las pernoctaciones de los viajeros y su recaudación suele destinarse a una finalidad específica, en la mayoría de ocasiones ligada a compensar al destino por los costes de los servicios públicos consumidos por los turistas y a la mejora o mantenimiento de la calidad medioambiental de dichos destinos. En la Comunitat Valenciana existe un gran debate alrededor de la tasa, su fundamentación, finalidad e idoneidad. A partir del mismo surge el presente informe, cuyo objetivo no es otro que arrojar luz, con cifras contrastadas, sobre este tributo. Para ello, el informe se organiza en tres bloques, en el primero se explica en qué consiste la tasa turística, cuál es generalmente su finalidad, los distintos tipos de tasa turística, su nivel de implantación lo largo del mundo y en España. Después de una leve semblanza de la coyuntura turística valenciana, se hace una simulación del impacto que podría tener la tasa en la Comunitat Valenciana y se tratan las ventajas e inconvenientes de la tasa, tras analizar las opiniones de diferentes colectivos afectados. Los bloques dos y tres proveen multitud de datos estadísticos para tratar sobre la idoneidad de la tasa. Así, en el bloque 2 se estiman los resultados económicos del sector turístico desde 2019, analizando la demanda turística, los indicadores de rentabilidad del sector hotelero e incidiendo, además, en la coyuntura turística debido a la pandemia asociada a la COVID-19. Se hace también una comparativa con Cataluña y Baleares, únicos lugares en España donde la tasa se ha implantado. Por último, el bloque tres analiza la oportunidad de la tasa teniendo en cuenta la diferente tipología de destinos de la Comunitat Valenciana. Tras estos tres bloques se ofrecen unas conclusiones generales del estudio y se indica la bibliografía utilizada en el mismo.Invat·tur (Instituto Valenciano de Tecnologías Turísticas
Reglas para la producción de una base de conocimientos en la construcción de tesauros.
The times are gone when the software for handling larger ammounts of data was sheer craftmanship. The last two decades have witnessed the rise of models aimed to setting up a formal and theoretical framework to afford coherence to databases design. Currently, the advance of Artificial Intelligence and related disciplines allows the management of data into an new context: the deductive data bases
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