Texas Sour Orange Juice Used in Scaffolds for Tissue Engineering

Fine fibers of polyhydroxybutyrate (PHB), a biopolymer, were developed via a centrifugal spinning technique. The developed fibers have an average diameter of 1.8 µm. Texas sour orange juice (SOJ) was applied as a natural antibacterial agent and infiltrated within the fibrous membranes. The antibacterial activity against common Gram-positive and Gram-negative bacteria (Staphylococcus aureus and Escherichia coli, respectively) was evaluated as well as cell adhesion and viability. The PHB/SOJ scaffolds showed antibacterial activity of up to 152% and 71% against S. aureus and E. coli, respectively. The cell studies revealed a suitable environment for cell growth and cell attachment. The outcome of this study opens up new opportunities for fabrication of fibrous materials for biomedical applications having multifunctional properties while using natural agents

PÓRTICOS DE ENSAYO EN LABORATORIOS: UNIENDO LA TEORÍA Y LA PRÁCTICA MEDIANTE EL FORTALECIMIENTO DE LA INVESTIGACIÓN Y LA ACADEMIA

Los pórticos de ensayo de materiales se constituyen en una herramienta trascendental para la caracterización del comportamiento mecánico de elementos estructurales de variados materiales. La definición de relaciones fundamentales como la de esfuerzo-deformación, que permite diseñar estructuras de manera eficiente, adecuada y segura, deviene de extensas campañas experimentales. El uso de estos pórticos posibilita la investigación multidisciplinaria en las materias relacionadas con el estudio de materiales y también permite el estudio detallado de elementos estructurales fabricados con diferentes materiales, elementos de reuso que puedan provenir de procesos industriales como fibras naturales o residuos de vidrio. Los resultados obtenidos a partir de ensayos principalmente sobre vigas, permiten establecer la línea de investigación en materiales y elementos estructurales a partir del estudio de las relaciones esfuerzo-deformación para posibilitar la estimación de propiedades de elasticidad y de resistencia en materiales como acero, hormigón armado, muros, entre otros. El presente trabajo tiene el propósito de mostrar las facultades del empleo de pórticos de ensayos para disminuir la brecha entre la formación teórica y la aplicación práctica a nivel académico e investigativo dentro la ingeniería estructural y de materiales, a través de una revisión de la evolución y la utilidad de este tipo de elementos en la enseñanza. Con este fin, se desarrolla una revisión bibliográfica de trabajos desarrollados principalmente a nivel Latinoamericano en laboratorios que cuentan con pórticos de ensayos, se describe la evolución de estos elementos, las características principales de pórticos en el medio, las normativas asociadas al desarrollo de pruebas en estos equipos y finalmente se realiza un breve análisis de resultados experimentales y su relevancia en la academia y la investigación

Draft Genome Sequence of a Multi-Metal Resistant Bacterium Pseudomonas putida ATH-43 Isolated from Greenwich Island, Antarctica

Indexación: Web of Science; Scopus.In this report we present the first draft genome sequence of a P. putida strain isolated from the Antarctic continent. The shotgun sequencing strategy, assembly, and subsequent annotation showed that the ATH-43 strain possesses a wide spectrum of genetic determinants involved in heavy metal and antibiotic resistance, apparently to cope with extreme oxidative stress conditions. P. putida ATH-43 genome now forms part of the 65 genomes of this species registered at the NCBI database (September, 2016) and it is highly related with the endophytic strain P. putida W619, which is also resistant to several heavy metals. Further characterization of multi-metal resistant psychrotrophic bacteria such as P. putida ATH-43 will be promising to develop novel strategies for heavy metal bioremediation in low temperature environments. All genome data has been submitted to NCBI.http://journal.frontiersin.org/article/10.3389/fmicb.2016.01777/ful

High Temperature Corrosion of Inconel 600 in NaCl-KCl Molten Salts

In this work the corrosion resistance of a high content nickel alloy, Inconel 600, was investigated in mixed NaCl-KCl salts at 700, 800, and 900°C for 100 hours in static air. Investigation was carried out using electrochemical techniques such as polarization curves, rest potential measurements, linear polarization resistance, and electrochemical impedance spectroscopy. Corroded specimens were analyzed by scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDS). Electrochemical measurements showed an increased degradation rate of Inconel 600 with increasing test temperature. SEM and EDS analysis show that the damage experienced by Inconel 600 is greater than that determined by electrochemical measurements. This damage was identified as internal corrosion due to the reaction of Cl2 with the alloying elements (Cr and Fe); however, at 900°C the internal damage was minor and it was associated with the nickel content in the alloy

The Rise of Cohabitation in the Southern Cone

This chapter analyses the increase in cohabitation in the Southern Cone (Argentina, Chile and Uruguay) and attempts to determine the extent to which consensual unions and marriages have similar traits or differ in the context of the cohabitation boom (Esteve et al. 2012). The first section of the chapter reviews the historical context of cohabitation in the Southern Cone. The second section uses census and survey data to analyse the trends in conjugal union formation in the three countries during the last 40 years. We analyse the patterns of both childbearing and union formation, as well as the differences between marriage and cohabitation based on educational attainment, labour market participation and household structure. The purpose of this analysis is to better understand whether the behaviour of married and cohabiting women with different characteristics are converging or diverging over time and tentatively, whether more egalitarian gender relationships are emerging in both types of conjugal unions

Towards precision medicine: defining and characterizing adipose tissue dysfunction to identify early immunometabolic risk in symptom-free adults from the GEMM family study

Interactions between macrophages and adipocytes are early molecular factors influencing adipose tissue (AT) dysfunction, resulting in high leptin, low adiponectin circulating levels and low-grade metaflammation, leading to insulin resistance (IR) with increased cardiovascular risk. We report the characterization of AT dysfunction through measurements of the adiponectin/leptin ratio (ALR), the adipo-insulin resistance index (Adipo-IRi), fasting/postprandial (F/P) immunometabolic phenotyping and direct F/P differential gene expression in AT biopsies obtained from symptom-free adults from the GEMM family study. AT dysfunction was evaluated through associations of the ALR with F/P insulin-glucose axis, lipid-lipoprotein metabolism, and inflammatory markers. A relevant pattern of negative associations between decreased ALR and markers of systemic lowgrade metaflammation, HOMA, and postprandial cardiovascular risk hyperinsulinemic, triglyceride and GLP-1 curves was found. We also analysed their plasma non-coding microRNAs and shotgun lipidomics profiles finding trends that may reflect a pattern of adipose tissue dysfunction in the fed and fasted state. Direct gene differential expression data showed initial patterns of AT molecular signatures of key immunometabolic genes involved in AT expansion, angiogenic remodelling and immune cell migration. These data reinforce the central, early role of AT dysfunction at the molecular and systemic level in the pathogenesis of IR and immunometabolic disorders

Spatio-temporal variation of the urban heat island in Santiago, Chile during summers 2005–2017

© 2020 by the authors. Licensee MDPI, Basel, Switzerland. Urban heat islands (UHIs) can present significant risks to human health. Santiago, Chile has around 7 million residents, concentrated in an average density of 480 people/km2. During the last few summer seasons, the highest extreme maximum temperatures in over 100 years have been recorded. Given the projections in temperature increase for this metropolitan region over the next 50 years, the Santiago UHI could have an important impact on the health and stress of the general population. We studied the presence and spatial variability of UHIs in Santiago during the summer seasons from 2005 to 2017 using Moderate Resolution Imaging Spectroradiometer (MODIS) satellite imagery and data from nine meteorological stations. Simple regression models, geographic weighted regression (GWR) models and geostatistical interpolations were used to find nocturnal thermal differences in UHIs of up to 9◦ C, as well as increases in the magnitude and extension of the daytime heat island from summer 2014 to 2017. Understanding the behavior of the UHI of Santiago, Chile, is important for urban planners and local decision makers. Additionally, understanding the spatial pattern of the UHI could improve knowledge about how urban areas experience and could mitigate climate change