Analytic height correlation function of rough surfaces derived from light scattering

We derive an analytic expression for the height correlation function of a rough surface based on the inverse wave scattering method of Kirchhoff theory. The expression directly relates the height correlation function to diffuse scattered intensity along a linear path at fixed polar angle. We test the solution by measuring the angular distribution of light scattered from rough silicon surfaces, and comparing extracted height correlation functions to those derived from atomic force microscopy (AFM). The results agree closely with AFM over a wider range of roughness parameters than previous formulations of the inverse scattering problem, while relying less on large-angle scatter data. Our expression thus provides an accurate analytical equation for the height correlation function of a wide range of surfaces based on measurements using a simple, fast experimental procedure.Comment: 6 pages, 5 figures, 1 tabl

Hydrogen sensing properties of Pt/lanthanum oxide-molybdenum oxide nanoplatelet/SiC based Schottky diode

An investigation of the electrical and hydrogen sensing properties of a novel Schottky diode based on a nanostructured lanthanum oxide-molybdenum oxide compound is presented herein. Molybdenum oxide (MoO3) nanoplatelets were grown on SiC substrates via thermal evaporation which was then subsequently coated with lanthanum oxide (La2O3) by RF sputtering. The current-voltage characteristics and hydrogen sensing performance (change in barrier height and sensitivity as well as the dynamic response) were examined from 25 to 300°C. At 180°C, a voltage shift of 2.23V was measured from the sensor while exposed to 1% hydrogen gas under a 100 μA constant reverse bias current. The results indicate that the presence of a La2O3 thin layer substantially improves the hydrogen sensitivity of the MoO3 nanoplatelets

L-carnitine reduces the adverse effects of ROS and up-regulates the expression of implantation related genes in in vitro developed mouse embryos

In vitro developed embryos are inevitably exposed to various reactive oxygen species (ROS) which may decrease the embryo's competence in assisted reproductive technology (ART) procedures. Optimization of embryo culture media using antioxidant agents could help to improve embryo quality and could overcome failures in current ART. The aim of this study was to evaluate the effects of L-carnitine (LC), an enhancer of mitochondrial activity and free radical scavenger, in culture media on early embryo competence and expression of ErbB1 and ErbB4 implantation related genes. Two-cell mouse embryos were cultured in the following four conditions: 1. LC group in media containing LC; 2.H 2O2 group exposed to H2O2 for 30 min and then transferred into a simple media; 3.H2O2+LC group exposed to H2O2 for 30 min and then transferred into a simple media containing LC; 4.the control group kept throughout in simple media. All groups were allowed to develop until the blastocyst stage. ErbB1 and ErbB4 expression were evaluated by Real-time PCR and immunocytochemistry. The expression of Sirt3 gene was also evaluated. Intracellular ROS levels were examined by DCFH-DA fluorescence intensity. In order to assess the morphological quality of the embryos, ICM and OCM number blastocyst cells were evaluated by using Hoechst and propidium iodide (PI) staining. ErbB1, ErbB4, ROS levels and cell number were compared across all in vitro groups. Our data reveal that LC significantly increases ErbB1 and ErbB4 gene and protein expression with intracellular ROS levels and Sirt3 gene expression significantly decreased after LC treatment. It is worth noting that an elevated cell number was observed in the LC-treated group compared with the other groups suggesting increased viability and/or proliferation. Our findings suggest that the use of LC could be helpful to improve preimplantation embryo culture media through its effects in decreasing ROS levels and the increase of implantation-related genes. © 2020 Elsevier Inc

Non-linear Finite-Time Tracking Control of Uncertain Robotic Manipulators Using Time-Varying Disturbance Observer-Based Sliding Mode Method

In this paper, a time-varying chattering-free disturbance observer-based position tracking control law of serial robotic manipulators is presented to track a reference signal in a finite time. The key idea is to employ a positive-increasing function associated with the control/observer objectives to improve the control performance. First, the model of an uncertain robotic manipulator is presented as the case study of the proposed strategy. Then, the time-varying form of the robotic manipulator model is obtained to provide finite-time boundedness using the first-order sliding mode method. Moreover, without any knowledge about the upper bounds of the uncertainties, a reduced-order observer is presented to estimate the uncertainties in a finite time. Subsequently, a disturbance observer-based finite-time position tracking control law is designed. The time-varying gains are provided to converge the position tracking error to a neighborhood of zero in a finite time. Finally, comparative simulations are presented to show the effectiveness of the proposed scheme compared to other existing strategies

Prácticas reflexivas del saber cultural Guaraní, en espacio de enseñanza - aprendizaje, fuera del contexto paraguayo

Anais do I Encontro de Iniciação Científica e de Extensão da Unila - Sessão de Artes e Linguística - 05/06/12 - 14h00 às 18h00 - Unila-Centro - Sala 16 - 3o PisoHemos empezado esa investigación con muchas preguntas para las que buscamos respuesta ¿Qué guaraní enseñar? ¿Qué contenido de gramática aplicar? ¿Qué interés tendrán los alumnos? Cómo se daría en pro - ceso de enseñanza y aprendizaje en el contexto extranjero. Esas interrogantes surgen a partir de decisio - nes como la enseñanza del guaraní, que por su naturaleza denota particularidades diferentes a otras len - guas y por lo tanto nos exigió nuevos planteamiento cuanto a su enseñanza y aprendizaje. La Lengua Guarani incorporada en diversos ámbitos de la universidade ha generado un matiz muy particular de co - nocimiento, saberes y curiosidades. Más allá del aprendizaje del idioma, se involucran otros saberes y ras - gos culturales guaraníes, no solo se ensenã y se aprende el idioma, sino también las experiencias del vivir y ser guaraní: las músicas, las danzas, la gastronomía, las leyendas como un todo del entorno de uso de la lengua. En análisis de las prácticas en clase de guaraní - fuera de un contexto paraguayo - ha explicitado el interés de los extranjeros en esos elementos de nuestra cultura. Reflexionar sobre cada acción: enseñan - za, aprendizaje, adquisición, objetivos del curso y prácticas de alumnos, professores y colaboradores pue - de aportar nuevos rumbos a la enseñanza y aprendizaje de lenguas en contextos de integración y de inter - culturalidad. Para llevar a cabo nuestro propósito de observar, analizar y traer los resultados a la práctica en el salón de clase, hemos tratado de hacer el registro de todas las actividades realizadas. Eso nos facilitó el trabajo de análisis de todo el proceso de enseñanza y aprendizaje, incluso, nuestras actitudes como do - centes por medio de una investigación acción colaborativa. Nuestra actuación como professores de nues - tra lengua materna - el guaraní - pudo aportar tanto conocimientos nuevos sobre la enseñanza de lengua como un reconocimiento y valoración de ese idioma no solo en Unila, sino en Foz do Iguaçu, Brasily en Paraguay. El análisis de nuestras actitudes como profesores y de los alumnos nos llevó muchas veces a re - plantear las clases y nuestra forma de pensar y actuar el proceso de enseñanza y aprendizaje de lenguas. A diferencia de lo que ocurre con idiomas próximos, la enseñanza del guaraní para hablantes de português y de español explicita la necesidad de repensar nuevas formas de transmisión de los saberes linguístico-cul - turales en nuestra universidad y en nuestros países. La metodología empleada en cuanto a las anotaciones del proceso realizado como reflexión del desarrollo de las clases, para una experiencia y mejora de lo rea - lizado. Se propicia, dinamismo, interés y el mismo aprendizaje a lo que se agrega el trabajo por práctica escrita y oral. En consecuencia, se logra crear un espacio favorable en la difusión del idioma, la cultura, saberes populares, etc. Su trasmisión forja el aprendizaje, el guaraní ha llegado a transformar pensamien - tos y actitudes, tabúes y desconocimientos. Valoramos la herencia de los guaraníes, valoramos y respeta - mos.Universidade Federal da Integração Latino-Americana (UNILA

Proton-deuteron radiative capture cross sections at intermediate energies

Differential cross sections of the reaction $p(d,^3{\rm He})\gamma$ have been measured at deuteron laboratory energies of 110, 133 and 180 MeV. The data were obtained with a coincidence setup measuring both the outgoing $^3$He and the photon. The data are compared with modern calculations including all possible meson-exchange currents and two- and three- nucleon forces in the potential. The data clearly show a preference for one of the models, although the shape of the angular distribution cannot be reproduced by any of the presented models.Comment: 6 pages, 6 figures, accepted for publication in EPJ

Dielectric and plasmonic vivaldi antennas for on-chip wireless communication

In this paper, different technologies enabling wireless on-chip communication are investigated. In particular, plasmonic Vivaldi antennas coupled to silicon waveguides and all-dielectric Vivaldi antennas are proposed. The design criteria and the performances of the two antenna configurations are also discussed

Investigation of the quasi-free domain in deuteron-deuteron break-up using spin observables

Precision measurements of vector and tensor analyzing powers of the 2H(d, dp)n break-up process for configurations in the vicinity of the quasi-free scattering regime with the neutron as spectator are presented. These measurements are performed with a polarized deuteron-beam with an energy of 65MeV/nucleon impinging on a liquid-deuterium target. The experiment was conducted at the AGOR facility at KVI using the BINA 4π-detection system. Events for which the final-state deuteron and proton are coplanar have been analyzed and the data have been sorted for various momenta of the missing neutron. In the limit of vanishing neutron momentum and at large deuteron-proton momentum transfer, the data agree well with the measured and theoretically predicted spin observables of the elastic deuteronproton scattering process. The agreement deteriorates rapidly with increasing neutron momentum and/or decreasing momentum transfer from the deuteron beam to the outgoing proton. This study reveals the presence of a significant contribution of final-state interactions even at very small neutron momenta