2,753 research outputs found

    Exposición mediante realidad virtual para el TOC: ¿Es factible?

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    Virtual reality exposure therapy (VRET) is receiving increased attention, especially in the fields of anxiety and eating disorders. This study is the first trial examining the utility of VRET from the perspective of OCD patients. Four OCD women assessed the sense of presence, emotional engagement, and reality judgment, and the anxiety and disgust levels they experimented in four scenarios, called the Contaminated Virtual Environment (COVE), in which they had to perform several activities. The COVE scenarios were presented on a Full HD 46” TV connected to a laptop and to a Kinect device. Results indicate that the COVE scenarios generated a good sense of presence. The anxiety and disgust levels increased as the virtual contamination increased, and the anxiety produced was related to the emotional engagement and sense of presence.La Exposición mediante Realidad Virtual (ERV) está recibiendo una atención cada vez mayor, especialmente para los trastornos de ansiedad y los alimentarios. Este estudio es el primer ensayo que evalúa la utilidad de la ERV desde la propia perspectiva de pacientes con Trastorno Obsesivo-Compulsivo (TOC). Cuatro mujeres con TOC evaluaron la sensación de presencia, implicación emocional, el juicio de realidad, y los niveles de ansiedad y asco que experimentaban en cuatro escenarios virtuales, que denominamos Entorno Virtual Contaminado (EVCO), en los que debían realizar varias actividades. Los escenarios se presentaron en una TV Full HD de 46’’, conectada a un ordenador y a un dispositivo Kinect. Los resultados indican que EVCO produjo una buena sensación de presencia. Los niveles de ansiedad y asco aumentaron a medida que aumentaba la “contaminación” de los escenarios, y la ansiedad se asoció con la sensación de presencia y la implicación emocional

    Effects of Education on the Intergenerational Transmission of Labor Income in Mexico

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    This paper studies the relationship between the labor market earnings of parents and their children, with a particular emphasis on education. We incorporate heterogeneity of levels of income in two ways: first, by examining the transmission mechanism of family income by grouping households according to income levels. Second, we use quantile regressions to evaluate how the earnings distribution changes over time. For this purpose, we use hourly earnings of the household head and decompose it into the estimated hourly earnings and a residual.Education, Labor Income

    Brewster quasi bound states in the continuum in all-dielectric metasurfaces from single magnetic-dipole resonance meta-atoms

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    Bound states in the continuum (BICs) are ubiquitous in many areas of physics, attracting especial interest for their ability to confine waves with infinite lifetimes. Metasurfaces provide a suitable platform to realize them in photonics; such BICs are remarkably robust, being however complex to tune in frequency-wavevector space.Here we propose a scheme to engineer BICs and quasi-BICs with single magnetic-dipole resonance meta-atoms. Upon changing the orientation of the magnetic-dipole resonances, we show that the resulting quasi-BICs,emerging from the symmetry-protected BIC at normal incidence, become transparent for plane-wave illumination exactly at the magnetic-dipole angle, due to a Brewster-like effect. While yielding infinite Q-factors at normalincidence(canonical BIC), these are termed Brewster quasi-BICs since a transmission channel is always allowed that slightly widens resonances at oblique incidences. This is demonstrated experimentally through reflectance measurements in the microwave regime with high-refractive-index mm-disk metasurfaces. Such Brewster-inspired configuration is a plausible scenario to achieve quasi-BICs throughout the electromagnetic spectrum inaccessible through plane-wave illumination at given angles, which could be extrapolated to other kind of waves.Comment: 15 pages, 7 figures; typos corrected, Figs. 3 & 5 modified, new Fig. 7 & references adde

    Robust free-spurious formulation of high order 2.5 dimensional electromagnetic problems by using finite elements

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    The 3D Finite Elements Method (FEM) is an extensively accepted tool for the analysis and design of microwaves/millimetre circuits and antennas based on the use of complex materials and geometries. Despite the huge memory capacity and computation speed of the current informatics systems, the method still suffers from an expensive computational cost when the domain is 3D. In many practical structures, the knowledge of the behaviour of one field component introduces a symmetry in the formulations that allows to project the physical problem onto a bi-dimensional mesh. The result of the former is a dramatic increase of the speed and ease of handling of such kind of problems, achieving efficient tools for the computer assisted design of many complex structures used in the electrical engineering nowadays. Because nothing is free, this simplification in the computation of the numerical problems is reached after a modification into the formulation and discretization of the model in the sense to introduce the symmetry of the field component into the basis functions. Because we need the three field components, we must divide the basis functions in two sets; one keeps the vector character and is applied to approximate the transversal or meridian component of the electromagnetic field and the other set is used for the longitudinal or azimuthal component. Then, we have to work with two elements, one is vector and the other is scalar. Frequently they are called hybrid elements, or 2.5D elements. This type of problems has been intensively studied by many researchers along the last two decades [1], [2], [3], [4], [5], [6]. However, only lower order basis has been used and, since our knowledge, it has not been developed a theory linking the development of the function spaces for the cited two elements, vector and scalar which make up the hybrid elements. This is especially true when the order of the elements increases, producing the apparition of the frightened spurious modes. Besides of the lack of a robust method to obtain these higher order hybrid elements for the 2.5D problems, we consider that it is worth reviewing these procedures, trying to increase its reliability and robustness. It should be a priority to incorporate the use of higher-order elements to the discretization of 2.5D problems, as the last developments relative to pre and post processors, new and more powerful meshers and solvers. In this way we can develop new numerical tools facing the more complex geometries containing field singularities, diverse materials and multiscale details with curved boundaries that conform the structures that electrical engineers handle nowadays. This work is an extension with some new results of previous presented at [5], [7]. A complete study of the design of conical dielectric core horn antennas, ended by both, convex-plane and double-convex dielectric lens, is carried on, taking advantage of the robust performance of the developed methods

    Atazanavir-Based Therapy Is Associated with Higher Hepatitis C Viral Load in HIV Type 1-Infected Subjects with Untreated Hepatitis C

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    Comunicación cortaWe assessed the relationship between atazanavir (ATV)-based antiretroviral treatment (ART) and plasma hepatitis C virus (HCV) viral load in a population of HIV/HCV-coinfected patients. HIV/HCV-coinfected patients who received ART based on a protease inhibitor (PI) or nonnucleoside reverse transcriptase inhibitor (NNRTI) were included. Patients were stratified by ART drug [ATV/rtv, lopinavir (LPV/rtv), efavirenz (EFV), nevirapine (NVP), and other PIs], HCV genotype (1/4 and 2/3), and IL28B genotype (CC and non-CC). The Kruskal-Wallis test and chi-squared test were used to compare continuous and categorical variables, respectively. Multivariate analysis consisted of a stepwise linear regression analysis. Six hundred and forty-nine HIV/HCV-coinfected patients were included. HCV genotype 1/4 patients who received ATV had higher HCV RNA levels [6.57 (5.9-6.8) log IU/ml] than those who received LPV [6.1 (5.5-6.5) log IU/ml], EFV [6.1 (5.6-6.4) log IU/ml], NVP [5.8 (5.5-5.9) log IU/ml], or other PIs [6.1 (5.7-6.4) log IU/ml] (p=0.014). This association held for the IL28B genotype (CC versus non-CC). The association was not found in patients carrying HCV genotypes 2/3. The linear regression model identified the IL28B genotype and ATV use as independent factors associated with HCV RNA levels. ATV-based therapy may be associated with a higher HCV RNA viral load in HIV/HCV-coinfected patients

    Comportamiento mecánico de mezclas de escoria vítrea de horno alto y metacaolín activadas alcalinamente. Estudio estadístico.

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    El proceso de fabricación de cemento Pórtland está asociado a un elevado consumo energético (térmico y eléctrico) y a aspectos medioambientales negativos. La industria cementera es una industria altamente contaminante, debido, en gran medida, a las elevadas cantidades de materias primas necesarias para la fabricación del crudo de cemento (explotación de canteras) y a la emisión a la atmósfera de gases (N2, CO2, O2, H2O, NOx y SO2) y partículas. Algunos de estos gases son causantes del efecto invernadero. El CO2 es el gas con mayor impacto medioambiental; siendo la industria cementera la responsable del 7% de las emisiones antropogénicas globales de CO2 a nivel mundial. Es por ello, que el estudio y desarrollo de cementos alternativos y más eco-eficientes que el cemento Portland, es un tema de gran impacto a nivel científico y tecnológico. Entre esos posibles cementos se encuentran los cementos alcalinos que son materiales conglomerantes obtenidos por la interacción química de materiales silicoaluminosos cálcicos y disoluciones fuertemente alcalinas. Diferentes materiales pueden ser susceptibles de activarse alcalinamente, entre ellos se encuentran las escorias vítreas de horno alto, las cenizas volantes y arcillas térmicamente activadas (Ej. metacaolín). En el presente trabajo de investigación se estudia el comportamiento mecánico de mezclas de escoria vítrea de horno alto y metacaolín activadas alcalinamente con disoluciones de NaOH. El objetivo de este estudio es conocer como afectan parámetros tales como la relación escoria/metacaolín, concentración de la disolución activadora, temperatura y tiempo de curado sobre el desarrollo resistente de las mezclas. A través del estudio estadístico realizado se ha podido establecer la influencia de cada variable y modelizar el comportamiento resistente de estos cementos alcalino

    Effectiveness of Motor Imagery on Motor Recovery in Patients with Multiple Sclerosis: Systematic Review

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    The effects of motor imagery (MI) on functional recovery of patients with neurological pathologies, such as stroke, has been recently proven. The aim of this study is to evaluate the effectiveness of MI on motor recovery and quality of life (QOL) in patients with multiple sclerosis (pwMS). A search was carried out in the following scientific databases: PubMed, CINAHL, PEDro, Scopus, Cochrane and Web of Science, up to November 2020. The grey literature and reference lists of potentially relevant articles were also searched. The Checklist for Measuring Quality and The Cochrane collaboration's tool were used to assess the methodological quality and risk of bias of the studies. Five studies were included in the systematic review. Findings showed that pwMS using MI had significant improvements in walking speed and distance, fatigue and QOL. In addition, several benefits were also found in dynamic balance and perceived walking ability. Although the evidence is limited, rehabilitation using MI with the application of musical and verbal guides (compared to non-intervention or other interventions), can produce benefits on gait, fatigue and QOL in pwMS with a low score in the Expanded Disability Status Scale.Department of Nursing and Physiotherapy (University of Cadiz, Spain

    Relationship between foot eversion and thermographic foot skin temperature after running

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    [EN] The main instruments to assess foot eversion have some limitations (especially for field applications), and therefore it is necessary to explore new methods. The objective was to determine the relationship between foot eversion and skin temperature asymmetry of the foot sole (difference between medial and lateral side), using infrared thermography. Twenty-two runners performed a running test lasting 30 min. Skin temperature of the feet soles was measured by infrared thermography before and after running. Foot eversion during running was measured by kinematic analysis. Immediately after running, weak negative correlations were observed between thermal symmetry of the rearfoot and eversion at contact time, and between thermal symmetry of the entire plantar surface of the foot and maximum eversion during stance phase (r = −0.3 and p = 0.04 in both cases). Regarding temperature variations, weak correlations were also observed (r = 0.4 and p < 0.05). The weak correlations observed in this study suggest that skin temperature is not related to foot eversion. However, these results open interesting future lines of researchSIDirección General de Investigación Científica y 397 Técnica (DGICT) (DEP2013-48420-P); Ministerio de 398 Educación, Cultura y Deporte (MECD) (Doctoral 399 Fellowship (FPU))

    Performance of Sulfonated Poly(Vinyl Alcohol)/Graphene Oxide Polyelectrolytes for Direct Methanol Fuel Cells

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    The use of nanotechnology along with the consideration of a functionalization and stabilization approach to poly(vinyl alcohol) (PVA) is considered useful for the preparation of cost-effective polyelectrolyte membranes. A set of nanocomposite and crosslinked membranes based on PVA/sulfosuccinic acid (SSA)/graphene oxide (GO) are prepared and analyzed as polyelectrolytes in direct methanol fuel cells (DMFCs). The crosslinking and sulfonation by the use of SSA enhances the stability and increase the proton-conducting sites in the PVA structure. The presence of GO augments the stability, remarkably decreases the methanol crossover, and enhances power density curves. An optimum value for proton conductivity is found for the 0.50 wt% of GO proportion, which decreases with higher concentrations of GO. Given the power density curve dependency on both the proton conductivity and the crossover reduction, the performance of these membranes as polyelectrolytes in DMFCs is strictly related to the balance between both factors. Therefore, a proportion of GO of 0.75 wt% may assure suitable proton conductivity of 3 mS cm−1 and high resistance to methanol permeability, reaching promising power density of 16 mW cm−2 with lower hydration levels
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