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This work aimed to characterize and compare the physicochemical properties of four pulse starches: bean, chickpea, lentil, and pea. Chemical proximate analysis, elemental composition, morphological grain characterization, crystalline structure, thermal analysis, FTIR analysis, and pasting properties were conducted. The proximate analysis shows that these starches have low fat, mineral, and protein content but high amylose values ranging from 29 to 36 % determined by colorimetry. Despite the high amylose content, the starches did not exhibit the typical behavior of an amylose-rich starch, with high peak viscosity and low breakdown and setback. It was found that this behavior was likely due to the large granule size of the ellipsoidal, spherical, and kidney-shaped granules and the high content of some minerals such as Na, Mg, K, Fe, Mn, P, and Si. The study also found that all pulse starches simultaneously contain monoclinic and hexagonal crystals, making them C-type starches. The findings were verified through the Rietveld analyses of X-ray diffraction patterns and differential scanning calorimetry, in which bimodal endothermic peaks evidenced both types of crystals being gelatinized.

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In this paper, the impact of temperature fluctuations in the entanglement of two qubits described by a spin-1/2 XX model is studied. To describe the out-of-equilibrium situation, superstatistics is used with fluctuations given by a χ^{2}-distribution function, and its free parameters are chosen in such a way that resembles the nonadditive Tsallis thermodynamics. In order to preserve the Legendre structure of the thermal functions, particular energy constraints are imposed on the density operator and the internal energy. Analytical results are obtained using an additional set of constraints after a parametrization of the physical temperature. We show that the well-known parametrization may lead to undesirable values of the physical temperature so that by analyzing the entropy as a function of energy, the correct values are found. The quantum entanglement is obtained from the concurrence and is compared with the case when the Tsallis restrictions are not imposed on the density operator.

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Porous silicon (PSi) on p++-type (111) silicon substrate has been fabricated by electronically etching method in hydrofluoric acid (HF) media from 5 to 110 mA/cm2 of anodizing current density. The problem of determining the optical properties of (111) PSi is board through implementing a photoacoustic (PA) technique coupled to an electrochemical cell for real-time monitoring of the formation of porous silicon thin films. PA amplitude allows the calculation of the real part of the films refractive index and porosity using the reflectance self-modulation due to the interference effect between the PSi film and the substrate that produces a periodic PA amplitude. The optical properties are studied from specular reflectance measurements fitted through genetic algorithms, transfer matrix method (TMM), and the effective medium theory, where the Maxwell Garnett (MG), Bruggeman (BR), and Looyenga (LLL) models were tested to determine the most suitable for pore geometry and compared with the in situ PA method. It was found that (111) PSi exhibit a branched pore geometry producing optical anisotropy and high scattering films.

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We present a methodology to fabricate one-dimensional porous silicon (PSi) photonic crystals in the visible range by controlled etching and monitored by photoacoustics. Photoacoustic can record in-situ information about changes in the optical path and chemical reaction as well as in temperature, refractive index, and roughness during porous layers formation. Radiometry imaging can determine the carrier distribution of c-Si substrate that is a fundamental parameter to obtain high-quality PSi films. An electrochemical cell was calibrated through a series of single PSi layers that allows knowing the PA amplitude period, porosity, and roughness as a function of the current density. Optical properties of single layers were determined using the reflectance response in the UV-Vis range to solve the inverse problem through genetic algorithms. PhC structures were designed using the transfer matrix method and effective media approximation.Based on the growth kinetics of PSi single layers, those structures were fabricated by electrochemical etching monitored and controlled by in-situ photoacoustics.

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Resumen Introducción: La mortalidad infantil está asociada con la pobreza y el menor nivel de desarrollo de las comunidades geográficas. Se realizo un estudio de la mortalidad infantil durante nueve años en el cantón central de Cartago, Costa Rica. Objetivo: Determinar los factores asociados con la muerte infantil y compararlos con los encontrados en la literatura internacional. Metodología Se determino cuáles son los factores asociados a la muerte infantil comparando entre cada variable la categoría más deprivada socialmente con la menos deprivada para esto se comparó la tasa de expuestos contra la tasa de no expuestos, se estableció la diferencia de tasas, la razón de prevalencia y el valor p. Resultados: Las variables con mayor riesgo para la muerte infantil fueron; año de muerte, escolaridad de la madre, edad al morir, peso al nacer, condición socioeconómica de la madre, complicaciones en el embarazo, tipo de riesgo en el embarazo, actividad remunerada de la madre, calidad de la vivienda y escolaridad del padre. Discusión: Como resultado se validó la teoría de que la pobreza y las condiciones de desarrollo son los mayores predictores de muerte infantil.

Abstract Introduction: Child Mortality is correlated with poverty and a lower development of geographic communities. A study of child mortality was made over nine years in the central area of Cartago, Costa Rica. Objetive: To determine the factors associated with the infant death and compare them with those found in the international literature. Methodology: The factors related to child mortality were determined by comparing the more socially deprived category with the least in each variable. For this purpose the ¨exposed¨ rate was compared against the ¨not exposed¨, a difference between the rates was established, along with the prevalence ratio and the p value. Results: The variables with a bigger risk for child death were; Year of death, mother's level of study, age at time of death, weight at birth, mother's socioeconomic condition, complications during pregnancy, type of risk in the pregnancy, mother's paid activities, quality of housing and father's level of study. Discussion: As a result a theory was validated, which states that poverty and development conditions are the biggest predictors of child death.

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This work is focused in the development of a modulated optical transmission system with temperature control to determine the thermal properties of biodiesels such as the cloud and freezing points. This system is able to determine these properties in real time without relying on the operator skills as indicated in the American Society for Testing Materials (ASTM) norms. Thanks to the modulation of the incident laser, the noise of the signal is reduced and two information channels are generated: amplitude and phase. Lasers with different wavelengths can be used in this system but the sample under study must have optical absorption at the wavelength of the laser.

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