A monolithic integrated photonic microwave filter

[EN] Meeting the increasing demand for capacity in wireless networks requires the harnessing of higher regions in the radiofrequency spectrum, reducing cell size, as well as more compact, agile and power-efficient base stations that are capable of smoothly interfacing the radio and fibre segments. Fully functional microwave photonic chips are promising candidates in attempts to meet these goals. In recent years, many integrated microwave photonic chips have been reported in different technologies. To the best of our knowledge, none has monolithically integrated all the main active and passive optoelectronic components. Here, we report the first demonstration of a tunable microwave photonics filter that is monolithically integrated into an indium phosphide chip. The reconfigurable radiofrequency photonic filter includes all the necessary elements (for example, lasers, modulators and photodetectors), and its response can be tuned by means of control electric currents. This is an important step in demonstrating the feasibility of integrated and programmable microwave photonic processors.The authors acknowledge financial support from the Spanish Centro para el Desarrollo Tecnologico Industrial (CDTI) through the NEOTEC start-up programme, the European Commission through the 7th Research Framework Programme project, Photonic Advanced Research and Development for Integrated Generic Manufacturing (FP7-PARADIGM), the Generalitat Valenciana through the Programa para grupos de Investigacion de Excelencia (PROMETEO) project code 2013/012, the Spanish Ministerio de Economia y Comercio (MINECO) via project TEC2013-42332-P, PIF4ESP, and the Unwersitat Politecnica de Valencia (UPVOV) through projects 10-3E-492 and 08-3E-008 funded by the Fondos Europeos de Desarrollo Regional (FEDER). J.S. Fandino acknowledges financial support from Formacion de Profesorado Universitario (FPU) grant AP2010-1595.Sanchez Fandiño, JA.; Muñoz Muñoz, P.; Doménech Gómez, JD.; Capmany Francoy, J. (2017). A monolithic integrated photonic microwave filter. Nature Photonics. 11(2):124-129. https://doi.org/10.1038/NPHOTON.2016.233S124129112Novak, D. et al. Radio-over-fiber technologies for emerging wireless systems. IEEE J. Quantum Electron. 52, 1–11 (2016).Waterhouse, R. & Novak, D. Realizing 5G: microwave photonics for 5G mobile wireless systems. IEEE Microw. Mag. 16, 84–92 (2015).Won, R. Microwave photonics shines. Nat. Photon. 5, 736 (2011).Capmany, J. & Novak, D. Microwave photonics combines two worlds. Nat. Photon. 1, 319–330 (2007).Yao, J. Microwave photonics. J. Lightw. Technol. 27, 314–335 (2009).Andrews, J. G. et al. What will 5G be? IEEE J. Sel. Areas Commun. 32, 1065–1082 (2014).Gosh, A., et al. Millimetre-wave enhanced local area systems: a high-data-rate approach for future wireless networks. IEEE J. Sel. Areas Commun. 32, 1152–1163 (2014).Marpaung, D. et al. Integrated microwave photonics. Laser Photon. Rev. 7, 506–538 (2013).Iezekiel, S., Burla, M., Klamkin, J., Marpaung, D. & Capmany, J. RF engineering meets optoelectronics: progress in integrated microwave photonics. IEEE Microw. Mag. 16, 28–45 (2015).Mitchell, J. E. Integrated wireless backhaul over optical access networks. J. Lightw. Technol. 32, 3373–3382 (2014).Liu, C., Wang, J., Cheng, L., Zhu, M. & Chang, G.-K. Key microwave-photonics technologies for next-generation cloud-based radio access networks. J. Lightw. Technol. 32, 3452–3460 (2014).Norberg, E. J., Guzzon, R. S., Parker, J. S., Johansson, L. A. & Coldren, L. A. Programmable photonic microwave filters monolithically integrated in InP/InGaAsP. J. Lightw. Technol. 29, 1611–1619 (2011).Guzzon, R., Norberg, E., Parker, J., Johansson, L. & Coldren, L. Integrated InP–InGaAsP tuneable coupled ring optical bandpass filters with zero insertion loss. Opt. Express 19, 7816–7826 (2011).Fandiño, J. S. & Muñoz, P. Photonics-based microwave frequency measurement using a double-sideband suppressed-carrier modulation and an InP integrated ring-assisted Mach–Zehnder interferometer filter. Opt. Lett. 38, 4316–4319 (2013).Burla, M. et al. On-chip ultra-wideband microwave photonic phase shifter and true time delay line based on a single phase-shifted waveguide Bragg grating. In IEEE International Topical Meeting on Microwave Photonics 92–95 (IEEE, 2013).Shi, W., Veerasubramanian, V., Patel, D. & Plant, D. Tuneable nanophotonic delay lines using linearly chirped contradirectioinal couplers with uniform Bragg gratings. Opt. Lett. 39, 701–703 (2014).Guan, B. et al. CMOS compatible reconfigurable silicon photonic lattice filters using cascaded unit cells for RF-photonic processing. IEEE J. Sel. Top. Quantum Electron. 20, 359–368 (2014).Khan, M. H. et al. Ultrabroad-bandwidth arbitrary radiofrequency waveform generation with a silicon photonic chip-based spectral shaper. Nat. Photon. 4, 117–122 (2010).Pagani, M. et al. Instantaneous frequency measurement system using four-wave mixing in an ultra-compact long silicon waveguide. In Proc. 41st European Conf. on Optical Communication (ECOC) 1–3 (IEEE, 2015).Khilo, A. et al. Photonic ADC: overcoming the bottleneck of electronic jitter. Opt. Express 20, 4454–4469 (2012).Wang, J. et al. Reconfigurable radio-frequency arbitrary waveforms synthesized in a silicon photonic chip. Nat. Commun. 6, 5957 (2015).Marpaung, D. et al. Si3N4 ring resonator-based microwave photonic notch filter with an ultrahigh peak rejection. Opt. Express 21, 23286–23294 (2013).Zhuang, L. et al. Ring resonator-based on-chip modulation transformer for high-performance phase-modulated microwave photonic links. Opt. Express 21, 25999–26013 (2013).Marpaung, D., Chevalier, L., Burla, M. & Roeloffzen, C. Impulse radio ultrawideband pulse shaper based on a programmable photonic chip frequency discriminator. Opt. Express 19, 24838–24848 (2011).Marpaung, D. On-chip photonic-assisted instantaneous microwave frequency measurement system. IEEE Photon. Technol. Lett. 25, 837–840 (2013).Burla, M. et al. On-chip CMOS compatible reconfigurable optical delay line with separate carrier tuning for microwave photonic signal processing. Opt. Express 19, 21475–21484 (2011).Tan, K. et al. Photonic-chip-based all-optical ultra-wideband pulse generation via XPM and birefringence in a chalcogenide waveguide. Opt. Express 21, 2003–2011 (2013).Pagani, M. et al. Tuneable wideband microwave photonic phase shifter using on-chip stimulated Brillouin scattering. Opt. Express 22, 28810–28818 (2014).Pérez, D., Gasulla, I. & Capmany, J. Software-defined reconfigurable microwave photonics processor. Opt. Express 23, 14640–14654 (2015).Capmany, J., Gasulla, I. & Pérez, D. Microwave photonics: the programmable processor. Nat. Photon. 10, 6–8 (2016).Zhuang, L., Roeloffzen, C. G. H., Hoekman, M., Boller, K.-J. & Lowery, A. J. Programmable photonic signal processor chip for radiofrequency applications. Optica 2, 854–859 (2015).Roeloffzen, C. G. et al. Silicon nitride microwave photonic circuits. Opt. Express 21, 22937–22961 (2013).Liu, W. et al. A fully reconfigurable photonic integrated signal processor. Nat. Photon. 10, 190–195 (2016).Madsen, C. K. & Zhao, J. H. Optical Filter Design and Analysis: A Signal Processing Approach (Wiley, 1999).Román, J., Frankel, M. Y. & Esman, R. D. Spectral characterization of fiber gratings with high resolution. Opt. Lett. 23, 939–941 (1998).Hernández, R., Loayssa, A. & Benito, D. Optical vector network analysis based on single-sideband modulation. Opt. Eng. 43, 2418–2421 (2004).Jinguji, K. & Oguma, M. Optical half-band filters. J. Lightw. Technol. 18, 252–259 (2000).Madsen, C. K. Efficient architectures for exactly realizing optical filters with optimum bandpass designs. IEEE Photon. Technol. Lett. 10, 1136–1138 (1998).Madsen, C. K. General IIR optical filter design for WDM applications using all-pass filters. J. Lightw. Technol. 18, 860–868 (2000).Smit, M. K. et al. An introduction to InP-based generic integration technology. Semicond. Sci. Technol. 29, 083001 (2014).Besse, P. A., Gini, E., Bachmann, M. & Melchior, H. New 2×2 and 1×3 multimode interference couplers with free selection of power splitting ratios. J. Lightw. Technol. 14, 2286–2293 (1996).Pérez, D. et al. Figures of merit for self-beating filtered microwave photonic systems. Opt. Express 24, 10087–10102 (2016).Zhuang, L. et al. Novel low-loss waveguide delay lines using Vernier ring resonators for on-chip multi-λ microwave photonic signal processors. Laser Photon. Rev. 7, 994–1002 (2013)

Las políticas públicas nacionales de Colombia para la formación de educadores infantiles

El presente trabajo tiene como objetivo delinear el estado del arte de las políticas públicas para la formación del profesorado en los últimos quince años en Colombia, en especial la formación del educador infantil. Para tal fin se realizó una extensa revisión bibliográfica de normativas, artículos y trabajos investigativos en el área. Se apuntan algunos puntos relevantes: el aumento de la importancia de la educación infantil en las últimas décadas, principalmente en el marco de nuevas políticas para la infancia. Aunque la normativa apunta a nuevos e innovadores parámetros educativos, el asistencialismo está en primer orden. Esto se refleja en la visión social de la infancia como momento restringido al cuidado, que disminuye la importancia de las intervenciones educativas planeadas y los aspectos educativos en general, agravado por la falta de profesionales de la educación infantil que fomenten y concreten el área de la educación infantil, y que construyan conocimiento práctico. Se recomienda invertir en la formación de docentes, valorizar la realización de investigación en el área, así como promover mayor profesionalización del personal, tomando medidas para la valorización del profesional de educación infanti

Phytochemicals as antibiotic alternatives to promote growth and enhance host health

There are heightened concerns globally on emerging drug-resistant superbugs and the lack of new antibiotics for treating human and animal diseases. For the agricultural industry, there is an urgent need to develop strategies to replace antibiotics for food-producing animals, especially poultry and livestock. The 2nd International Symposium on Alternatives to Antibiotics was held at the World Organization for Animal Health in Paris, France, December 12-15, 2016 to discuss recent scientific developments on strategic antibiotic-free management plans, to evaluate regional differences in policies regarding the reduction of antibiotics in animal agriculture and to develop antibiotic alternatives to combat the global increase in antibiotic resistance. More than 270 participants from academia, government research institutions, regulatory agencies, and private animal industries from >25 different countries came together to discuss recent research and promising novel technologies that could provide alternatives to antibiotics for use in animal health and production; assess challenges associated with their commercialization; and devise actionable strategies to facilitate the development of alternatives to antibiotic growth promoters (AGPs) without hampering animal production. The 3-day meeting consisted of four scientific sessions including vaccines, microbial products, phytochemicals, immune-related products, and innovative drugs, chemicals and enzymes, followed by the last session on regulation and funding. Each session was followed by an expert panel discussion that included industry representatives and session speakers. The session on phytochemicals included talks describing recent research achievements, with examples of successful agricultural use of various phytochemicals as antibiotic alternatives and their mode of action in major agricultural animals (poultry, swine and ruminants). Scientists from industry and academia and government research institutes shared their experience in developing and applying potential antibiotic-alternative phytochemicals commercially to reduce AGPs and to develop a sustainable animal production system in the absence of antibiotics.Fil: Lillehoj, Hyun. United States Department of Agriculture. Agricultural Research Service; ArgentinaFil: Liu, Yanhong. University of California; Estados UnidosFil: Calsamiglia, Sergio. Universitat Autònoma de Barcelona; EspañaFil: Fernandez Miyakawa, Mariano Enrique. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación en Ciencias Veterinarias y Agronómicas. Instituto de Patobiología; ArgentinaFil: Chi, Fang. Amlan International; Estados UnidosFil: Cravens, Ron L.. Amlan International; Estados UnidosFil: Oh, Sungtaek. United States Department of Agriculture. Agricultural Research Service; ArgentinaFil: Gay, Cyril G.. United States Department of Agriculture. Agricultural Research Service; Argentin

Evaluation of classification algorithms in the Google Earth Engine platform for the identification and change detection of rural and periurban buildings from very high-resolution images

[EN] Building change detection based on remote sensing imagery is a key task for land management and planning e.g., detection of illegal settlements, updating land records and disaster response. Under the post- classification comparison approach, this research aimed to evaluate the feasibility of several classification algorithms to identify and capture buildings and their change between two time steps using very-high resolution images (<1 m/pixel) across rural areas and urban/rural perimeter boundaries. Through an App implemented on the Google Earth Engine (GEE) platform, we selected two study areas in Colombia with different images and input data. In total, eight traditional classification algorithms, three unsupervised (K-means, X-Means y Cascade K-Means) and five supervised (Random Forest, Support Vector Machine, Naive Bayes, GMO maximum Entropy and Minimum distance) available at GEE were trained. Additionally, a deep neural network named Feature Pyramid Networks (FPN) was added and trained using a pre-trained model, EfficientNetB3 model. Three evaluation zones per study area were proposed to quantify the performance of the algorithms through the Intersection over Union (IoU) metric. This metric, with a range between 0 and 1, represents the degree of overlapping between two regions, where the higher agreement the higher IoU values. The results indicate that the models configured with the FPN network have the best performance followed by the traditional supervised algorithms. The performance differences were specific to the study area. For the rural area, the best FPN configuration obtained an IoU averaged for both time steps of 0.4, being this four times higher than the best supervised model, Support Vector Machines using a linear kernel with an average IoU of 0.1. Regarding the setting of urban/rural perimeter boundaries, this difference was less marked, having an average IoU of 0.53 in comparison to 0.38 obtained by the best supervised classification model, in this case Random Forest. The results are relevant for institutions tracking the dynamics of building areas from cloud computing platfo future assessments of classifiers in likewise platforms in other contexts.[ES] La detección de cambios de áreas construidas basada en datos de teledetección es una importante herramienta para el ordenamiento y la administración del territorio p.e.: la identificación de construcciones ilegales, la actualización de registros catastrales y la atención de desastres. Bajo el enfoque de comparación post-clasificación, la presente investigación tuvo como objetivo evaluar la funcionalidad de varios algoritmos de clasificación para identificar y capturar las construcciones y su cambio entre dos fechas de análisis usando imágenes de alta resolución (<1 m/píxel) en ámbitos rurales y límites del perímetro urbano municipal. La anterior evaluación fue llevada a cabo a través de una aplicación desarrollada mediante la plataforma Google Earth Engine (GEE), donde se alojaron y analizaron diferentes imágenes y datos de entrada sobre dos áreas de estudio en Colombia. En total, ocho algoritmos de clasificación tradicional, tres no supervisados (K-means, X-Means y Cascade K-Means) y cinco supervisados (Random Forest, Support Vector Machine, Naive Bayes, GMO maximum Entropy y Minimum distance) fueron entrenados empleando GEE. Adicionalmente, se entrenó una red neuronal profunda denominada Feature Pyramid Networks (FPN) sobre la cual se aplicó la estrategia de modelos preentrenados, usando pesos del modelo EfficientNetB3. Por cada una de las dos áreas de estudio, tres zonas de evaluación fueron propuestas para cuantificar la funcionalidad de los algoritmos mediante la métrica Intersection over Union (IoU). Esta métrica representa la evaluación de la superposición de dos regiones y tiene un rango de valores de 0 a 1, donde a mayor coincidencia de las imágenes mayor es el valor de IoU. Los resultados indican que los modelos configurados con la red FPN tienen la mejor funcionalidad, seguido de los algoritmos tradicionales supervisados. Las diferencias de la funcionalidad fueron específicas por área de estudio. Para el ámbito rural, la mejor configuración de FPN obtuvo un IoU promedio entre ambas fechas de 0,4, es decir, cuatro veces el mejor modelo supervisado, correspondiente al Support Vector Machine de kernel Lineal con un IoU de 0,1. Respecto al área de límites del perímetro urbano municipal, esta diferencia fue menos marcada, con un IoU promedio de 0,53 en comparación con el 0,38 derivado del mejor modelo de clasificación supervisada, que en este caso fue Random Forest. Los resultados de esta investigación son relevantes para entidades responsables del seguimiento de las dinámicas de las áreas construidas a partir de plataformas de procesamiento en la nube como GEE, estableciendo una línea base para futuros estudios evaluando la funcionalidad de los clasificadores disponibles en otros contextos.Los autores agradecen a las Subdirecciones de Catastro, y Geografía y Cartografía del IGAC. Esta investigación hace parte de la licencia del programa GEO-GEE administrada por la Subdirección de Geografía y Cartografía. Se agradece igualmente al equipo de EODataScience por su soporte constante en los desarrollos técnicos de esta investigación.Coca-Castro, A.; Zaraza-Aguilera, MA.; Benavides-Miranda, YT.; Montilla-Montilla, YM.; Posada-Fandiño, HB.; Avendaño-Gomez, AL.; Hernández-Hamon, HA.... (2021). Evaluación de algoritmos de clasificación en la plataforma Google Earth Engine para la identificación y detección de cambios de construcciones rurales y periurbanas a partir de imágenes de alta resolución. Revista de Teledetección. 0(58):71-88. http://hdl.handle.net/10251/169765OJS718805

Identification of 12 new susceptibility loci for different histotypes of epithelial ovarian cancer.

To identify common alleles associated with different histotypes of epithelial ovarian cancer (EOC), we pooled data from multiple genome-wide genotyping projects totaling 25,509 EOC cases and 40,941 controls. We identified nine new susceptibility loci for different EOC histotypes: six for serous EOC histotypes (3q28, 4q32.3, 8q21.11, 10q24.33, 18q11.2 and 22q12.1), two for mucinous EOC (3q22.3 and 9q31.1) and one for endometrioid EOC (5q12.3). We then performed meta-analysis on the results for high-grade serous ovarian cancer with the results from analysis of 31,448 BRCA1 and BRCA2 mutation carriers, including 3,887 mutation carriers with EOC. This identified three additional susceptibility loci at 2q13, 8q24.1 and 12q24.31. Integrated analyses of genes and regulatory biofeatures at each locus predicted candidate susceptibility genes, including OBFC1, a new candidate susceptibility gene for low-grade and borderline serous EOC

Global Retinoblastoma Presentation and Analysis by National Income Level.

Importance: Early diagnosis of retinoblastoma, the most common intraocular cancer, can save both a child's life and vision. However, anecdotal evidence suggests that many children across the world are diagnosed late. To our knowledge, the clinical presentation of retinoblastoma has never been assessed on a global scale. Objectives: To report the retinoblastoma stage at diagnosis in patients across the world during a single year, to investigate associations between clinical variables and national income level, and to investigate risk factors for advanced disease at diagnosis. Design, Setting, and Participants: A total of 278 retinoblastoma treatment centers were recruited from June 2017 through December 2018 to participate in a cross-sectional analysis of treatment-naive patients with retinoblastoma who were diagnosed in 2017. Main Outcomes and Measures: Age at presentation, proportion of familial history of retinoblastoma, and tumor stage and metastasis. Results: The cohort included 4351 new patients from 153 countries; the median age at diagnosis was 30.5 (interquartile range, 18.3-45.9) months, and 1976 patients (45.4%) were female. Most patients (n = 3685 [84.7%]) were from low- and middle-income countries (LMICs). Globally, the most common indication for referral was leukocoria (n = 2638 [62.8%]), followed by strabismus (n = 429 [10.2%]) and proptosis (n = 309 [7.4%]). Patients from high-income countries (HICs) were diagnosed at a median age of 14.1 months, with 656 of 666 (98.5%) patients having intraocular retinoblastoma and 2 (0.3%) having metastasis. Patients from low-income countries were diagnosed at a median age of 30.5 months, with 256 of 521 (49.1%) having extraocular retinoblastoma and 94 of 498 (18.9%) having metastasis. Lower national income level was associated with older presentation age, higher proportion of locally advanced disease and distant metastasis, and smaller proportion of familial history of retinoblastoma. Advanced disease at diagnosis was more common in LMICs even after adjusting for age (odds ratio for low-income countries vs upper-middle-income countries and HICs, 17.92 [95% CI, 12.94-24.80], and for lower-middle-income countries vs upper-middle-income countries and HICs, 5.74 [95% CI, 4.30-7.68]). Conclusions and Relevance: This study is estimated to have included more than half of all new retinoblastoma cases worldwide in 2017. Children from LMICs, where the main global retinoblastoma burden lies, presented at an older age with more advanced disease and demonstrated a smaller proportion of familial history of retinoblastoma, likely because many do not reach a childbearing age. Given that retinoblastoma is curable, these data are concerning and mandate intervention at national and international levels. Further studies are needed to investigate factors, other than age at presentation, that may be associated with advanced disease in LMICs