TRANSFERENCIA DE MASA II

GUÍA DE EVALUACIÓN DEL APRENDIZAJ

Determination of the minimum integral entropy, water sorption and glass transition temperature to establishing critical storage conditions of beetroot juice microcapsules by spray drying

The aim of this work was to microencapsulate beetroot juice (BJ) (Beta vulgaris L.) by spray-drying using as protective colloid gum Arabic. The adsorption isotherms of the microcapsules and the minimum integral entropy (∆S int)T were determined at 25, 35 and 40 ◦C. The glass transition temperature (Tg) was measured by differential scanning calorimetry and modeled by GordonTaylor equation. The water contents-water activity (M-aW ) sets obtained from (∆S int)T , and critical water content (CWC) and critical water activity (CWA) from the Tg were similar, being in the range of water content of 5.11-7.5 kg H2O/100 kg d.s. and in the water activity range of 0.532-0.590. These critical storage conditions were considered as the best conditions for increase the stability of the microcapsules, where the percentage of retention Betanin in the microcapsules was higher compared with other storage conditions in the temperature and aw range studied. Keywords: beetroot juice, microcapsules, minimum integral entropy, glass transition temperature, critical water content, critical water activity

Encapsulación por gelación iónica de aceite de sésamo con mezclas de alginato de sodio-mucílago de nopal: Eficiencia de encapsulación y estabilidad oxidativa

This study provides a new way for preventing the oxidation of sesame oil by ionic gelation method, where SO can be encapsulated in sodium alginate-nopal mucilage hydrogel beads as wall material. The SA-NM hydrogel beads had heterogeneous surface morphologies, where el NM acted as structural support and controlling fractures in the beads after drying process, making the gel matrix more flexible. SA-NM hydrogel beads after the drying process leads to an irregular spherical shape that the SA beads. SA-NM hydrogel beads is characterized by high yield (>83.34%) and encapsulation efficiency (> 75.44%), and limited surface oil ( 75.44%) than SA beads (63.48%), and provided better protection to SO against oxidation during storage than the SA beads and free SO oil. Oxidation kinetics were of zero-order in all cases. The release kinetics of SO was diffusion controlled and was significantly slower for SA-NM than for SA beads. Our results indicate that SA-NM mixtures may be considered as potential additives for food industry applications.The authors wish to acknowledge the partial financial support of this research to the Universidad Autónoma del Estado de México through grant 4738/2019/CI

Biological characterization of a biodegradable scaffold for common bile duct replacement in an experimental model

Background: The nanofiber scaffolds achieved by the electrospinning technique have been used to develop several biological tissues, the nanofibers obtained by electrospinning procure a favorable microenvironment to mimic the extracellular matrix. Methods: Study type was of experimental. Study conducted at National Autonomous University of Mexico, from May 2018- May 2022. The protocol was approved by the research and ethics commissions of the UNAM school of medicine. A viscoelastic solution of polylactic-co-glycolic acid (PLGA) and polycaprolactone (PCL) in a 70:30 ratio and gelatin (Gel) in an 80:20 ratio was prepared while a dynamic collector was used with the electrospinning technique. Results: Mechanical and biological tests were carried out on the scaffold obtained by electrospinning; the resultant scaffold achieves good mechanical matching and structural similarity between the graft and the extrahepatic bile duct. Conclusions: In this study we managed to create a porous, biocompatible scaffold with good cell adhesion and proliferation, potentially applicable to tissue engineering, especially for the replacement of tubular organs such as blood vessels, bile ducts, and urethra

EVALUACIÓN DEL DESEMPEÑO DE SISTEMAS DE RADIO COGNITIVO CON DIFERENTES DISTRIBUCIONES DEL TIEMPO DE SERVICIO DE LOS USUARIOS SECUNDARIOS (EVALUATION OF THE PERFORMANCE OF COGNITIVE RADIO SYSTEMS WITH DIFFERENT DISTRIBUTIONS OF THE SERVICE TIME OF SECONDARY USERS)

Este trabajo estudia el desempeño de sistemas de radio cognitivo con diferentes distribuciones de probabilidad del tiempo de servicio de los usuarios secundarios. Para ello, se desarrolló un simulador de eventos discretos del sistema de radio cognitivo. En particular, se considera que el tiempo de servicio de los usuarios secundarios sigue una distribución de probabilidad log-normal y ésta es aproximada mediante distribuciones de probabilidad hiper-exponenciales de diferente orden. Para el cálculo de los parámetros de las distribuciones hiper-exponenciales se utiliza el algoritmo de Maximización de la Esperanza (EM). Los resultados obtenidos muestran que, mediante la distribución hiper-exponencial se pueden aproximar diferentes distribuciones de probabilidad como la log-normal sin pérdida significativa en la precisión de los resultados numéricos de las diferentes métricas de desempeño. Este resultado es relevante porque facilita el tratamiento y análisis matemático de sistemas de radio cognitivo.In this paper, performance evaluation of cognitive radio networks (CRNs) with different probability density functions for the service time of secondary users is studied. To this end, a discrete event simulation program that captures the fundamental aspects of CRNs is developed. In particular, it is assumed that the secondary service time of many real life applications is well characterized by the log-normal distribution. In this work, the log-normal model is systematically approximated by n-th order hyper-exponential distributions. The parameters of the n-th order hyper-exponential distribution are computed by the well-known Expectation Maximization (EM) algorithm. Numerical results show that, the hyper-exponential distribution can be used for approximating the log-normal behaviour of the secondary service time without significative loss of precision on the obtained results for the different performance metrics. This result is relevant because the mathematical (queueing) analysis of CRN with log-normal service time is possible by means of approximating the log-normal behavior of the service time by the hyper-exponential model

May-Thurner syndrome: a review

May-Thurner syndrome (MTS) is an underdiagnosed entity and level of suspicious should be raised during evaluation of deep vein thrombosis (DVT) of the left lower limb, especially in women between the third and fifth decades of life. To correctly identify MTS, high clinical suspicion, and imaging studies such as phlebography, magnetic resonance imaging (MRI), computed tomography (CT), and intravascular ultrasound are required. In correct clinical context, CT/MRI venography can be used to facilitate early diagnosis and treatment that includes pharmaco-mechanical thrombolysis with angioplasty and stenting, both of which minimize late morbidity from post-thrombotic syndrome

Genome of Herbaspirillum seropedicae Strain SmR1, a Specialized Diazotrophic Endophyte of Tropical Grasses

The molecular mechanisms of plant recognition, colonization, and nutrient exchange between diazotrophic endophytes and plants are scarcely known. Herbaspirillum seropedicae is an endophytic bacterium capable of colonizing intercellular spaces of grasses such as rice and sugar cane. The genome of H. seropedicae strain SmR1 was sequenced and annotated by The Paraná State Genome Programme—GENOPAR. The genome is composed of a circular chromosome of 5,513,887 bp and contains a total of 4,804 genes. The genome sequence revealed that H. seropedicae is a highly versatile microorganism with capacity to metabolize a wide range of carbon and nitrogen sources and with possession of four distinct terminal oxidases. The genome contains a multitude of protein secretion systems, including type I, type II, type III, type V, and type VI secretion systems, and type IV pili, suggesting a high potential to interact with host plants. H. seropedicae is able to synthesize indole acetic acid as reflected by the four IAA biosynthetic pathways present. A gene coding for ACC deaminase, which may be involved in modulating the associated plant ethylene-signaling pathway, is also present. Genes for hemagglutinins/hemolysins/adhesins were found and may play a role in plant cell surface adhesion. These features may endow H. seropedicae with the ability to establish an endophytic life-style in a large number of plant species

Observació i estudis. Productes i usuaris

Facultat de Belles Arts, Universitat de Barcelona. Assignatura: Artefactes i usos: disseny inclusiu, Curs: 2022-2023, Coordinador: Miquel Mallol Esquef

A Universal Power-law Prescription for Variability from Synthetic Images of Black Hole Accretion Flows

We present a framework for characterizing the spatiotemporal power spectrum of the variability expected from the horizon-scale emission structure around supermassive black holes, and we apply this framework to a library of general relativistic magnetohydrodynamic (GRMHD) simulations and associated general relativistic ray-traced images relevant for Event Horizon Telescope (EHT) observations of Sgr A*. We find that the variability power spectrum is generically a red-noise process in both the temporal and spatial dimensions, with the peak in power occurring on the longest timescales and largest spatial scales. When both the time-averaged source structure and the spatially integrated light-curve variability are removed, the residual power spectrum exhibits a universal broken power-law behavior. On small spatial frequencies, the residual power spectrum rises as the square of the spatial frequency and is proportional to the variance in the centroid of emission. Beyond some peak in variability power, the residual power spectrum falls as that of the time-averaged source structure, which is similar across simulations; this behavior can be naturally explained if the variability arises from a multiplicative random field that has a steeper high-frequency power-law index than that of the time-averaged source structure. We briefly explore the ability of power spectral variability studies to constrain physical parameters relevant for the GRMHD simulations, which can be scaled to provide predictions for black holes in a range of systems in the optically thin regime. We present specific expectations for the behavior of the M87* and Sgr A* accretion flows as observed by the EHT

Capitulo 3. Ciencias Sociales, Artes y Humanidades

La investigación busca describir los significados psicológicos en relación con la felicidad, partiendo del sujeto común no experto en la materia. Para ello se utilizará la técnica de Redes Semánticas Naturales Modificadas (RSNM). Esto en el contexto de la UNAD Zona Sur, específicamente con el cuerpo docente de las diferentes escuelas académicas, excepto los que pertenecen al programa de psicología. Esta última decisión en razón a prevenir alguna influencia en los significados derivada de la formación disciplinar de tales docentes, téngase en cuenta que el tema de la felicidad ha sido objeto de estudio desde la psicología. Este es un estudio sobre los significados psicológicos acerca de la felicidad en docentes de la UNAD Zona Sur. Esto a través de la técnica de RSNM, la cual se orienta justamente a dicho propósito. Esto en articulación con el proyecto “Felicidad: un estudio mixto desde la perspectiva de docentes y estudiantes de psicología de dos universidades de Latinoamérica”, en el que vienen trabajando docentes de la UNAD en convenio con la UNAM (Universidad Nacional Autónoma de México)