Development of a high-performance W-band duplexer for plasma diagnosis using a single band with dual circular polarization

Discrepancia entre la información que aparece en el artículo que indica que el copyright es de Elsevier, y la información que aparece en la página de la revista y en el Copyright Clearance Center que indican © 2019 The Authors. Published by Elsevier B.V., así como que el artículo está publicado en Open Access under a Creative Commons licenceThis work presents the design and experimental validation of a high performance, compact, waveguide duplexer operating from 91.5 to 96.5 GHz for its integration in diverse W-band microwave equipment as in plasma diagnosis applications. It uses a single frequency band, with two signals discriminated by different orthogonal circular polarization, which is generated by means of a septum orthomode transducer (OMT) polarizer. Moreover, this component is optimized loaded with the horn antenna for improving the overall system performance. It is explained how these two components are integrated into a very compact duplexer, designed using efficient numerical algorithms. The manufacturing process by mean of high precision milling, and including electrical discharge machining (EDM) has led to excellent performances. The measured return loss level and isolation are higher than 30 dB, and the insertion loss level is below 0.3 dB. Finally, the key parameter in this device, which reflects the symmetry in the manufacturing process, i.e., the axial ratio, is lower than 0.6 dB for both polarizations, an excellent result showing the potential of the presented designThis work was supported by the Spanish government under grants (ADDMATE) TEC2016-76070-C3-1/2-R (Agencia Estatal de Investigación, Spain, Fondo Europeo de Desarrollo Regional: AEI/FEDER/UE) and the program of Comunidad de Madrid, Spain S2013/ICE-3000 (SPADERADARCM

Diavideos: a Diabetes Health Video Portal

Diavideos1 is a web platform that collects trustworthy diabetes health videos from YouTube and offers them in a easy way. YouTube is a big repository of health videos, but good content is sometimes mixed with misleading and harmful videos such as promoting anorexia [1].Diavideos is a web portal that provides easy access to a repository of trustworthy diabetes videos. This poster describes Diavideos and explains the crawling method used to retrieve these videos from trusted channels

Experimental investigation of the aerodynamic flow in the aircraft carrier ski-jump by means of PIV

Computational Fluid Dynamics (CFD) methods have opened a new field to perform aerodynamic studies saving money and time. The difficulties presented by this method to calculate complex flow field problems imply that CFD validation is needed to provide correct results. Experimental data have recently been used to validate the accuracy of CFD predictions. Particle Image Velocimetry (PIV) has shown to be a powerful tool in the investigation of complex flows. The aim of this paper is to present results from PIV experiments that would be interesting for CFD validation. Regarding aircraft operations, the short runway available implies the necessity of equipment which helps to take-off performances. Ski-jump ramp system improves aircraft performances by an increment of lift resulting in successful take-off operations. The ski-jump ramp presence generates a complex flow bounded by a turbulent shear layer and a low velocity recirculation bubble over the end of the flight deck. The adverse effects on the aircraft aerodynamics affect to pilot safe operations, so this region is an interesting problem to be studied by means of wind tunnel experimental tests

The Energy Cost of Extracting Critical Raw Materials from Tailings: The Case of Coltan

Niobium and tantalum are mainly produced from columbite–tantalite ores, and 60% of their production is nowadays located in the Democratic Republic of Congo and Rwanda. The concentration of supply, the scarcity, the wide range of use in all electronic devices, and the expected future demand boosted by the clean and digital transition means that Nb and Ta have high supply risks. In this context, extraction from rich Ta and Nb tailings from abandoned mines could partly offset such risks. This study analyzes the energy cost that the reprocessing of both elements from tailings would have. To that end, we simulate with HSC Chemistry software the different processes needed to beneficiate and refine both metals from zinc tailings as a function of Nb and Ta concentration. At current energy and metal prices, tantalum recovery from rich Ta-Nb tailings would be cost-effective if ore-handling costs were allocated to a paying metal. By way of contrast, niobium recovery would not be favored unless market prices increase

Desarrollo y aplicaciones de un modelo de crecimiento para plantaciones de Pinus radiata D. Don en El Bierzo (León)

A dynamic growth model for Pinus radiata D. Don plantations in El Bierzo (Spain) was developed with data from two inventories of permanent plots, of between 7 and 36 years old, established by the University of León. In this model, stand conditions at any point in time are defined by three state variables (stand basal area, number of trees per hectare and dominant height).Themodel includes three transition functions derived by the generalized algebraic difference approach to enable projection of the state variables at any particular time. Once they are known, the number of trees in each diameter class is estimated with a distribution function, by recovery of the parameters of theWeibull function by use of the moments method. Finally, a generalized height-diameter function and a taper function allow estimation of total or merchantable stand volume. The model provides satisfactory predictions for a time interval of three years. Simulation of the growth of four stands under two silvicultural regimes and two different sites confirm that the estimates provided by the overall model adequately represent the effects of both stand density and site quality. Other applications for the model are analysed and discussed.Se ha desarrollado un modelo dinámico de crecimiento para plantaciones de Pinus radiata D. Don en El Bierzo (León) a partir de datos de dos inventarios de parcelas permanentes, de entre 7 y 36 años de edad, establecidas por la Universidad de León. En este modelo, las condiciones del rodal en un instante dado están definidas por tres variables de estado (área basimétrica, número de pies por hectárea y altura dominante). El modelo incluye tres funciones de transición obtenidas mediante la metodología de ecuaciones en diferencias algebraicas generalizadas que permite la proyección de las variables de estado a un determinado instante en el tiempo. Una vez conocidas las variables de estado, una función de distribución estima el número de pies en cada clase diamétrica mediante la metodología de recuperación de los parámetros de la función deWeibull usando el método de los momentos. Finalmente, una función de altura-diámetro generalizada y una función de perfil de tronco permiten la estimación del volumen total o comercial del rodal. El modelo proporciona predicciones satisfactorias para un intervalo de proyección de tres años. La simulación del crecimiento de cuatro rodales bajo dos regímenes selvícolas distintos y dos calidades de estación diferentes corrobora que las estimaciones proporcionadas por el modelo global representan adecuadamente los efectos de la densidad de la masa y la calidad de la estación. Finalmente se analizan y discuten otras aplicaciones del modelo elaborado

“I Was Determined to Fulfill This Image of Myself That I Wanted of a ‘good Asian Student’”: A Photovoice Study of Asian American College Student Mental Health

Asian American (AsA) youth and emerging adults are growing at a faster rate than all other racial and ethnic populations in the United States. Burgeoning empirical evidence shows that they are experiencing increased adverse mental health outcomes since the start of the COVID-19 pandemic. Additionally, trends in AsA youth and emerging adults’ utilization and help-seeking behaviors remain low. Health equity scholars posit that the model minority stereotype continues to obscure and minimize these mental health disparities. The current study aims to contribute to this vital research through a Photovoice study with AsA emerging adults. Fourteen AsA undergraduate students (M age = 19.77 years old; SD = 1.12) produced photographs and captions and participated in semi-structured interviews to describe mental health. Four themes were developed: (1) mind–body health connection and the belief that mental health is about the synchronization of one’s mind and body; (2) environmental connectedness and the view that mental health is connected to nature; (3) social connectedness and how interpersonal relationships influence mental health; and (4) the internalization of the “good Asian student” stereotype and its impact on mental health. Implications for culturally tailored prevention and intervention strategies are discussed to ultimately improve health equity

Improved photoenergy properties of low-emissivity coatings deposited by sputtering with an ion gun treatment

This work studies the effect of ion treatment on low-emissivity (low-e) coatings deposited by magnetron sputtering. Specifically, we have investigated the application of an ion treatment in the dielectric layer before deposition of a layer of silver. This reduces layer roughness which means the silver layer can be deposited with enhanced characteristics. We have also evaluated the etching rate on the SnOx layer due to the ion treatment on already deposit coatings of equal thicknesses. Subsequently, we studied the effects on the coating's photoenergy properties. For equivalent coatings, we found that those treated with ions were more transparent in the visible region, more reflective, and had a lower emissivity, which are essential requirements for low-e coatings applied in architectural glass

Orbital cycles, differential subsidence and internal factors controlling the high-frequency sequence architecture in a Sinemurian shallow carbonate platform (Mallorca island, Spain)

The ~125 m thick lower to lowermost upper Sinemurian peritidal to shallow subtidal platform carbonates in the Llevant Mountains of Mallorca (Spain) have been analysed from four stratigraphic sections, to provide new data on the hierarchical stacking pattern of high-frequency depositional sequences. Due to the fact that in shallow water environments the stacking of carbonate facies can be controlled by external (allocyclic) and internal (autocyclic) processes, deciphering the dominant controls on the high-frequency sequence architecture of these platforms is a challenge. The studied carbonates encompass a high variety of facies representative of open lagoon, internal bars, restricted lagoon and tidal flats with local beach sands. Based on a detailed analysis of vertical facies trends and bounding surfaces, large-, medium- and small-scale sequences have been identified within the long-term transgressive-regressive facies cycle defined by the entire succession. Large-scale sequences (~10–30 m thick) and medium-scale sequences (~1–10 m thick) are generally shallowing-upward sequences bounded by sharp facies changes to relatively deeper facies, and have been related to sea-level variations driven by long- (~400 kyr) and short- (~100 kyr) eccentricity cycles respectively. The overprinting of differential subsidence (probably related to extensional tectonic) and carbonate production and accumulation processes varied throughout time, controlling the lateral continuity and preservation potential of the ~100 kyr medium-scale sequences. Shallowing-upward, locally aggradational, small-scale sequences (~0.3 to 5 m thick) are very variable in number and thickness and cannot be correlated between sections, pointing out that their most important controlling factor was the internal processes (hiatuses and erosion related to subaerial exposure at the peritidal caps, lateral migration of internal bars, local wave and currents patterns, depositional and erosional processes related to spring tides and storms) in the frame of a complex mosaic of facies within the studied platform

Evaluación de los carotenoides en especies y variedades nativas de mamey y cambios durante la maduración

En Panamá el nombre mamey es dado a un grupo de frutas de la familia Pouteria con pulpa naranjas a roja. En este grupo se incluyen las especies Pouteria sapota, Pouteria viridisy Pouteriafossicola. Estas especies son nativas de México y América Central (Domínguez et al., 20 10) y en Panamá se encuentran ampliamente distribuidas. El fruto de los mameyes posee un alto contenido de nutrientes, es de sabor dulce y se consume fresco y procesado como bebidas, helados (etc.). El color de la pulpa del mamey maduro se debe a la cantidad y tipo de carotenoides que contiene (Murillo, et al., 2010) . Los carotenoides de los alimentos se han asociado con beneficios para la salud, tales como protección contra el cáncer, prevención de enfermedades crónicas (enfermedades cardiovasculares, cataratas, degeneración macular) y enfermedades degenerativas como (Fiedor y Burda, 2014; Kusmita et al., 2022; Lakey-beitia et al., 2017; Turcsi et al., 2016) Utilizando HPLC-DAD, se han observado 47 picos correspondientes a carotenoides, de los cuales 34 han sido plenamente identificados, (Murillo et. al. 2016). Por la diversidad de carotenoides de esta fruta, algunos carotenoides eluyen como mezclas y se hace dificil la identificación. Por otro lado, hasta el momento no se han estudiado los cambios en los carotenoides, de la pulpa, durante la maduración, ni los carotenoides presentes en las especies P. viridis y P, fossicola y sus variedades. En este estudio, cuantificamos simultáneamente los carotenoides amarillos y rojos y los comparamos con los cuantificados solo a 450 nm. Encontramos que, la cuantificación a una sola longitud de onda subestima los carotenoides totales. Observamos que, durante la maduración aumenta el contenido de los carotenoides, siendo la mayor proporción en los carotenoides rojos. Demostramos que, existe una gran variabilidad en el contenido de carotenoides, entre frutos de un mismo árbol, cuando los resultados se expresan en jig/g y demostramos que el perfil cromatográfico (%) es un mejor indicador de los carotenoides de esa variedad. Combinando la cromatografia semipreparativa con columna Ci 8 y la cromatografia analítica con C30, logramos separar e identificar 11 carotenoides que generalmente se superponen utilizando cromatográfica analítica con C30. Cuando se compara los carotenoides entre las tres especies de mamey (Pouteria sapota, Pouteria fossicola y Pouteria viridis), encontramos que en todas las variedades de estas especies están presentes los mismos carotenoides, aunque no se logró observar un patrón que caracteriza una especie determinada