Acoustically driven arrayed waveguide grating

We demonstrate compact tunable phased-array wavelength-division multiplexers driven by surface acoustic waves (SAWs) in the low GHz range. The devices comprise two couplers, which respectively split and combine the optical signal, linked by an array of single-mode waveguides (WGs). Two different layouts are presented, in which multi-mode interference couplers or free propagating regions were separately employed as couplers. The multiplexers operate on five equally distributed wavelength channels, with a spectral separation of 2 nm. A standing SAW modulates the refractive index of the arrayed WGs. Each wavelength component periodically switches paths between the output channel previously asigned by the design and the adjacent channels, at a fixed applied acoustic power. The devices were monolithically fabricated on (Al,Ga)As. A good agreement between theory and experiment is achieved

Acercamiento al arte negroafricano desde una didáctica inclusiva

La inclusión requiere de una posición de los diferentes logros de cada cultura como referentes universales en los mismos términos que los propios, esto es, valorados en función de la aportación realizada. A pesar de ello, en los ámbitos educativos subyace una actitud etnocentrista que deslegitimiza el logro artístico de las culturas negroafricanas situándolas dentro de la esfera de lo primitivo o curioso. No obstante, los logros artísticos negroafricanos son claramente significativos tanto estética como conceptualmente, lo que nos permite reivindicar una didáctica específica en arte negroafricano distanciada de las premisas etnocéntricas así como de los procesos de deslegitimación y desestimación coloniales. Estos planteamientos han derivado en una discriminación formal y conceptual del objeto negroafricano, que hemos de rectificar incluyendo propuestas de integración no asimilacionista del arte negroafricano en las enseñanzas artísticas. Inclusion requires a position of different achievements of each culture as universal references in the same terms as their own, that is, valued based on the contribution made by each group. Despite this, there is an underlying ethnocentric attitude in educational settings that delegitimizes the artistic achievement of Negro-African cultures, placing them within the sphere of the primitive or curious. However, Negro-African artistic achievements are clearly significant both aesthetically and conceptually, which allows us to claim a specific didactics in Negro-African art distanced from ethnocentric premises as well as from colonial delegitimization and dismissal processes. These approaches have led to a formal and conceptual discrimination of the Black African object, which we must rectify by including proposals for the non-assimilationist integration of Black African art in artistic teachings

Tunable Interferometers Driven by Coherent Surface Acoustic Phonons

[EN] We demonstrate a compact tunable photonic modulator driven by surface acoustic waves (SAWs) in the low GHz frequency range. The device follows a well-known Mach-Zehnder interferometer (MZI) structure with three output channels, built upon multi-mode interference (MMI) couplers. The light continuously switches paths between the central and the side channels, avoiding losses and granting a 180¿-dephasing synchronization between them. The modulator was monolithically fabricated on (Al,Ga)As, and can be used as a building block for more complex photonic functionalities. It can also be implemented in other material platforms such as Silicon or (In,Ga)P. Light modulated at multiples of the fundamental acoustic frequency can be accomplished by adjusting the applied acoustic power. An excellent agreement between theory and experiment is achievedCrespo-Poveda, A.; Hernández-Mínguez, A.; Biermann, K.; Tahraoui, A.; Gargallo-Jaquotot, B.; Muñoz, P.; Santos, P.... (2016). Tunable Interferometers Driven by Coherent Surface Acoustic Phonons. MRS Advances. 1651-1656. doi:10.1557/adv.2016.234S16511656Beck, M., de Lima, M. M., Wiebicke, E., Seidel, W., Hey, R., & Santos, P. V. (2007). Acousto-optical multiple interference switches. Applied Physics Letters, 91(6), 061118. doi:10.1063/1.2768889Soldano, L. B., & Pennings, E. C. M. (1995). Optical multi-mode interference devices based on self-imaging: principles and applications. Journal of Lightwave Technology, 13(4), 615-627. doi:10.1109/50.372474De Lima, M. M., Beck, M., Hey, R., & Santos, P. V. (2006). Compact Mach-Zehnder acousto-optic modulator. Applied Physics Letters, 89(12), 121104. doi:10.1063/1.2354411Crespo-Poveda, A., Hey, R., Biermann, K., Tahraoui, A., Santos, P. V., Gargallo, B., … de Lima, M. M. (2013). Synchronized photonic modulators driven by surface acoustic waves. Optics Express, 21(18), 21669. doi:10.1364/oe.21.021669Crespo-Poveda, A., Hernández-Mínguez, A., Gargallo, B., Biermann, K., Tahraoui, A., Santos, P. V., … de Lima, M. M. (2015). Acoustically driven arrayed waveguide grating. Optics Express, 23(16), 21213. doi:10.1364/oe.23.021213Sun, J., Timurdogan, E., Yaacobi, A., Hosseini, E. S., & Watts, M. R. (2013). Large-scale nanophotonic phased array. Nature, 493(7431), 195-199. doi:10.1038/nature1172

Large-eddy simulation of spectral coherence in a wind turbine wake

This work is mainly dedicated to the study of the characteristics of spectral coherence of turbulence fluctuations in wind turbine wakes. A computational fluid dynamics (CFD) code has been implemented using a large-eddy simulation (LES) approach, which is thought to be conceptually more suitable for studying the turbulence evolution in a wind turbine wake. Comparisons with experimental data from the Nørrekær Enge II Windfarm, in Denmark, and with an analytical model proposed by Panofsky and Dutton have been performed, and the results are found to be in reasonable agreement with both

Cuestionario de representaciones de la menopausia: adaptación y propuesta de versión en español

Introduction. The aging of women is a natural event called menopause, which requires its study for the various manifestations and how they influence during her life. Objective. To carry out the design and cultural adaptation of the Spanish version of the menopause representations questionnaire through validity and reliability tests. Methods. Research on the adaptation and validation design of the questionnaire, with the participation of women between 42 and 65 years of age, attended in first level health care facilities. A random sample of 230 women was used and the English version of the Menopause Representations Questionnaire was considered for the adaptation, back translation was performed, content validity through the expert judgment technique, convergent validity through Spearman’s correlation coefficient, internal consistency analysis through Cronbach’s Alpha coefficient and confirmatory factor analysis through Kaiser-Meyer-Olkin sample adequacy. Results. The mean age was 52.87 ± 6.29, the translation maintained the meaning of the original words, and there were no modifications in the evaluation of comprehension. Content validity by expert judgment showed a value of 0.79 according to Kappa coefficient. All the dimensions showed significant correlation for convergent validity, the reliability in the four dimensions ranged between 0.68 and 0.79 and a total reliability of 0.80. It was not necessary to eliminate questions and the confirmatory analysis was accepted. Conclusion. It is the first version translated into Spanish, has acceptable validity and reliability, can be used in clinical interventions and epidemiological studies, and is useful for describing experiences from a bio-psychosocial and cultural perspective.Introducción. El envejecimiento de la mujer es un evento natural denominado menopausia que requiere su estudio por las diversas manifestaciones y como estas influyen durante su vida. Objetivo. Realizar el diseño y adaptación cultural del cuestionario de representaciones de la menopausia versión en español mediante pruebas de validez y confiabilidad. Métodos. Investigación de adaptación y diseño de validación de cuestionario, participaron mujeres entre 42 a 65 años, atendidas en establecimientos del primer nivel de atención. Se utilizó una muestra aleatoria conformada por 230 mujeres y se consideró la versión en inglés de Menopause Representations Questionnaire para la adaptación. Se realizó la traducción inversa, validez de contenido mediante juicio de expertos, validez convergente a través del coeficiente de correlación de Spearman, análisis de consistencia interna mediante el coeficiente de Alfa de Cronbach y análisis factorial confirmatorio mediante la adecuación de muestra de Kaiser-Meyer-Olkin. Resultados. La edad promedio fue 52,87 ± 6,29 años. La traducción mantuvo el significado de palabras originales, en la valoración de la compresión no se presentaron modificaciones. La validez de contenido presentó un valor de 0,79 según coeficiente de Kappa. Todas las dimensiones mostraron correlación significativa para la validez convergente, la confiabilidad en las cuatro dimensiones osciló entre 0,68 y 0,79 y una confiabilidad total de 0,80. No fue necesario eliminar preguntas y se aceptó el análisis confirmatorio. Conclusión. Es la primera versión traducida al español, tiene una validez y confiabilidad aceptable, puede ser utilizado en intervenciones clínicas y estudios epidemiológicos y útil para describir experiencias desde la perspectiva bio-psicosocial y cultural

Estudio de la herencia y mapeo de la resistencia de Ceratitis capitata (Wiedemann, 1824) (Diptera, Tephritidae) al insecticida λ-cihalotrina

La mosca mediterránea de la fruta, Ceratitis capitata (Wiedemann, 1824), es una de las principales plagas de cítricos y otros frutales en España. Las actuales estrategias de control, basadas mayoritariamente en el uso de insecticidas, están viendo amenazada su eficacia debido a la aparición de resistencia en poblaciones de campo. Recientemente se ha descrito resistencia metabólica a lambda-cihalotrina mediada por P450s. Con el fin de estudiar el tipo de herencia de la resistencia a lambda-cihalotrina, se realizaron cruzamientos recíprocos entre una línea de laboratorio resistente a este insecticida y una línea susceptible, se obtuvieron la generación F1 y la F2 y se realizó el retrocruce de la F1 con el parental susceptible. Los resultados muestran que la herencia de la resistencia es completamente dominante y autosómica, y que no se ajusta a un modelo mendeliano monogénico. Asimismo, se está realizando un mapeo genético de la resistencia a lambda-cihalotrina a partir de los individuos ensayados en el estudio de la herencia, con el propósito de identificar marcadores moleculares que nos permitan la detección precoz y el seguimiento de la resistencia en campo, facilitando así el control de la plaga. Por último, mediante el simulacro en laboratorio de distintos escenarios de tratamiento se ha podido determinar que la rotación de lambda-cihalotrina con spinosad resulta eficaz para el manejo de la resistencia a lambda-cihalotrina

Calibration and performance tests of detectors for laser-accelerated protons

We present the calibration and performance tests carried out with two detectors for intense proton pulses accelerated by lasers. Most of the procedures were realized with proton beams of 0.46-5.60 MeV from a tandem accelerator. One approach made use of radiochromic films, for which we calibrated the relation between optical density and energy deposition over more than three orders of magnitude. The validity of these results and of our analysis algorithms has been confirmed by controlled irradiation of film stacks and reconstruction of the total beam charge for strongly non-uniform beam profiles. For the spectral analysis of protons from repeated laser shots, we have designed an online monitor based on a plastic scintillator. The resulting signal from a photomultiplier directly measured on a fast oscilloscope is especially useful for time-of-flight applications. Variable optical filters allow for suppression of saturation and an extension of the dynamic range. With pulsed proton beams we have tested the detector response to a wide range of beam intensities from single particles to 3 ×105 protons per 100 ns time interval.Project funded by the Spanish Ministry of Economy and Competitiveness and co-funded with FEDER's funds within the INNPACTO 2011 program under Grant No. IPT-2011-0862-900000. This work was supported by the Spanish Plan Nacional de Investigacion Cientifica, Desarrollo e Innovacion Tecnologica (I+D+i) under Grant No. TEC 2013-48036-C3-1-R and the Valencian Local Government under Grants PROMETEOII/2013/010 and ISIC 2011/013. The work of A. J. Gonzalez is financed by CSIC with a JAE-Doc contract under Junta de Ampliacion de Estudios program, cofinanced by the European Social Fund.Peer Reviewe

Spitzer observations of NGC2264: The nature of the disk population

NGC2264 is a young cluster with a rich circumstellar disk population which makes it an ideal target for studying the evolution of stellar clusters. Our goal is to study its star formation history and to analyse the primordial disk evolution of its members. The study presented is based on data obtained with Spitzer IRAC and MIPS, combined with deep NIR ground-based FLAMINGOS imaging and previously published optical data. We build NIR dust extinction maps of the molecular cloud associated with the cluster, and determine it to have a mass of 2.1x10^3Msun above an Av of 7mag. Using a differential K_s-band luminosity function of the cluster, we estimate the size of its population to be 1436$\pm$242 members. The star formation efficiency is ~25%. We identify the disk population: (i) optically thick inner disks, (ii) anaemic inner disks, and (iii) disks with inner holes, or transition disks. We analyse the spatial distribution of these sources and find that sources with thick disks segregate into sub-clusterings, whereas sources with anaemic disks do not. Furthermore, sources with anaemic disks are found to be unembedded (Av<3mag), whereas the clustered sources with thick disks are still embedded within the parental cloud. NGC2264 has undergone more than one star-forming event, where the anaemic and extincted thick disk population appear to have formed in separate episodes. We also find tentative evidence of triggered star-formation in the Fox Fur Nebula. In terms of disk evolution, our findings support the emerging disk evolution paradigm of two distinct evolutionary paths for primordial optically thick disks: a homologous one where the disk emission decreases uniformly at NIR and MIR wavelengths, and a radially differential one where the emission from the inner region of the disk decreases more rapidly than from the outer region (forming transition disks).Comment: accepted for publishing in A&

Results of a combined monolithic crystal and an array of ASICs controlled SiPMs

[EN] In this work we present the energy and spatial resolutions we have obtained for a γ ray detector based on a monolithic LYSO crystal coupled to an array of 256 SiPMs. Two crystal configurations of the same trapezoidal shape have been tried. In one approach all surfaces were black painted but the exit one facing the photosensor array which was polished. The other approach included a retroreflector (RR) layer coupled to the entrance face of the crystal powering the amount of transmitted light to the photosensors. Two coupling media between the scintillator and the SiPM array were used, namely direct coupling by means of optical grease and coupling through an array of light guides. Since the same operational voltage was supplied to the entire array, it was needed to equalize their gains before feeding their signals to the Data Acquisition system. Such a job was performed by means of 4 scalable Application Specific Circuits (ASICs). An energy resolution of about 24.4% has been achieved for the direct coupling with the RR layer together with a spatial resolution of approximately 2.9 mm at the detector center. With the light guides coupling the effects of image compression at the edges are significantly minimized, but worsening the energy resolution to about 33.1% with a spatial resolution nearing 4 mm at the detector center. & 2013 Elsevier B.V. All rights reserved.cknowledgments This work was supported by the Centre for Industrial Technological Development co-funded by FEDER through the Technology Fund (DREAM Project, IDI-20110718), the Spanish Plan Nacional de Investigación Científica, Desarrollo e Innovación Tecnológica (IþDþI) under Grant no. FIS2010-21216-CO2-01 and the Valencian Local Government under Grant PROMETEO 2008/114Conde Castellanos, PE.; González Martínez, AJ.; Hernández Hernández, L.; Bellido, P.; Iborra Carreres, A.; Crespo Navarro, E.; Moliner Martínez, L.... (2014). Results of a combined monolithic crystal and an array of ASICs controlled SiPMs. Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment. 734:132-136. https://doi.org/10.1016/j.nima.2013.08.079S13213673