Recuperación de sulfato de aluminio a partir de lodos generados en plantas de potabilización de agua

Se estudió la recuperación mediante ácido sulfúrico, de sulfato de aluminio a partir de lodos recolectados durante las diferentes rutinas de operación y mantenimiento de los sedimentadores en plantas de potabilización. Se efectuaron ensayos de jarras a pHs 1,5, 2,5 y 3,5 y tiempos de mezcla lenta de 5, 30 y 100 minutos. Se alcanzaron porcentajes de recuperación de aluminio entre 18 y 64% y soluciones con concentraciones entre 8,9 y 1510 mg Al/l. Finalmente, se evaluó la factibilidad económica de la reutilización en el proceso de potabilización, de la solución de coagulante recuperado

Fabricación de películas anódicas porosas sobre titanio mediante oxidación electrolítica por plasma

Resumen Se obtuvieron recubrimientos anódicos sobre Ti mediante oxidación electrolítica por plasma en soluciones de ácido sulfúrico (H2SO4) con diferentes concentraciones de ácido fosfórico (H3PO4) como aditivo. Se evaluó el comportamiento frente a la corrosión de los recubrimientos mediante Espectroscopía de Impedancia Electroquímica (EIE) en soluciones simuladas de fluidos corporales (SBF). La caracterización mediante SEM/EDS y espectroscopía Raman permitió observar una alta influencia del contenido de H3PO4 en la morfología y composición de los recubrimientos. Palabras clave: óxidos de titanio, oxidación electrolítica por plasma, recubrimientos anódicos, SBF, biomateriales. Fabrication of porous anodic layers on titanium by plasma electrolytic oxidation Abstract Anodic coatings were obtained on Ti through plasma electrolytic oxidation in sulfuric acid (H2SO4) solutions containing phosphoric acid (H3PO4) as an additive. The coatings corrosion behavior was evaluated by means of Electrochemical Impedance Spectroscopy (EIS) in Simulated Body Fluid solution (SBF). Characterization of the coatings was made using SEM/EDS and Raman spectroscopy, It allowed to observe great influence in its morphology and composition due to phosphoric acid content into the coatings. Keywords: titanium oxides, plasma electrolytic oxidation, anodic coatings, SBF, biomaterials

Fabricación de películas anódicas porosas sobre titanio mediante oxidación electrolítica por plasma

Resumen Se obtuvieron recubrimientos anódicos sobre Ti mediante oxidación electrolítica por plasma en soluciones de ácido sulfúrico (H2SO4) con diferentes concentraciones de ácido fosfórico (H3PO4) como aditivo. Se evaluó el comportamiento frente a la corrosión de los recubrimientos mediante Espectroscopía de Impedancia Electroquímica (EIE) en soluciones simuladas de fluidos corporales (SBF). La caracterización mediante SEM/EDS y espectroscopía Raman permitió observar una alta influencia del contenido de H3PO4 en la morfología y composición de los recubrimientos. Palabras clave: óxidos de titanio, oxidación electrolítica por plasma, recubrimientos anódicos, SBF, biomateriales. Fabrication of porous anodic layers on titanium by plasma electrolytic oxidation Abstract Anodic coatings were obtained on Ti through plasma electrolytic oxidation in sulfuric acid (H2SO4) solutions containing phosphoric acid (H3PO4) as an additive. The coatings corrosion behavior was evaluated by means of Electrochemical Impedance Spectroscopy (EIS) in Simulated Body Fluid solution (SBF). Characterization of the coatings was made using SEM/EDS and Raman spectroscopy, It allowed to observe great influence in its morphology and composition due to phosphoric acid content into the coatings. Keywords: titanium oxides, plasma electrolytic oxidation, anodic coatings, SBF, biomaterials

Enzymatic hydrolysis of cassava stalk pretreated with the alkaline method

This study was developed with the aim of evaluating the pH, enzymatic complex load and temperature effects on the saccharification of pretreated cassava stalks (CS) using the response surface methodology (RSM). The factor levels evaluated were temperature 35 - 40°C, pH 4.0 - 5.0 and dose of enzymatic complex Accellerase 1500™ 2.9 - 14.5 FPU/g of substrate. The reducing sugar (RS) response was used. The pH was controlled through the use of hydrochloric acid and sodium hydroxide solutions and the system was shaken orbitally at 120 rpm with a solids loading of 10% w/v. The fitted model showed that the optimal operating conditions were: pH 4.0, 38°C and enzyme dose of 14.5 FPU/g substrate, reaching a sugar concentration of 18.4 g L-1

Miocarditis aguda: diagnóstico mediante resonancia magnética cardiaca

Cardiomyopathies are a common cause of morbidity and mortality. Myocarditis, which is included among specific cardiomyopathies, frequently presents non-specific clinical manifestations and thus may be difficult to diagnose, or even be misdiagnosed. Traditionally employed diagnostic techniques, including endomyocardial biopsy, have been shown to be of limited value. Following its overall implantation in clinical practice, cardiac magnetic resonance imaging (MRI) is nowadays widely considered to be the best non-invasive diagnostic tool available for diagnosing myocarditi

Fructose metabolism in Chromohalobacter salexigens: interplay between the Embden–Meyerhof–Parnas and Entner–Doudoroff pathways

Background The halophilic bacterium Chromohalobacter salexigens metabolizes glucose exclusively through the Entner–Doudoroff (ED) pathway, an adaptation which results in inefficient growth, with significant carbon overflow, especially at low salinity. Preliminary analysis of C. salexigens genome suggests that fructose metabolism could proceed through the Entner–Doudoroff and Embden–Meyerhof–Parnas (EMP) pathways. In order to thrive at high salinity, this bacterium relies on the biosynthesis and accumulation of ectoines as major compatible solutes. This metabolic pathway imposes a high metabolic burden due to the consumption of a relevant proportion of cellular resources, including both energy molecules (NADPH and ATP) and carbon building blocks. Therefore, the existence of more than one glycolytic pathway with different stoichiometries may be an advantage for C. salexigens. The aim of this work is to experimentally characterize the metabolism of fructose in C. salexigens. Results Fructose metabolism was analyzed using in silico genome analysis, RT-PCR, isotopic labeling, and genetic approaches. During growth on fructose as the sole carbon source, carbon overflow was not observed in a wide range of salt concentrations, and higher biomass yields were reached. We unveiled the initial steps of the two pathways for fructose incorporation and their links to central metabolism. While glucose is metabolized exclusively through the Entner–Doudoroff (ED) pathway, fructose is also partially metabolized by the Embden–Meyerhof–Parnas (EMP) route. Tracking isotopic label from [1-13C] fructose to ectoines revealed that 81% and 19% of the fructose were metabolized through ED and EMP-like routes, respectively. Activities of enzymes from both routes were demonstrated in vitro by 31P-NMR. Genes encoding predicted fructokinase and 1-phosphofructokinase were cloned and the activities of their protein products were confirmed. Importantly, the protein encoded by csal1534 gene functions as fructose bisphosphatase, although it had been annotated previously as pyrophosphate-dependent phosphofructokinase. The gluconeogenic rather than glycolytic role of this enzyme in vivo is in agreement with the lack of 6-phosphofructokinase activity previously described. Conclusions Overall, this study shows that C. salexigens possesses a greater metabolic flexibility for fructose catabolism, the ED and EMP pathways contributing to a fine balancing of energy and biosynthetic demands and, subsequently, to a more efficient metabolism.University of Murcia and University of Seville was supported by projects: BIO2015-63949-R, BIO2014-54411-C2-1-REuropa MINECO/FEDER RTI2018-094393-B-C21Fundación Séneca (Grant no. 19236/PI/14

PROCESO DE INFORMACIÓN EN EL FORTALECIMIENTO DE LA GESTIÓN COMUNITARIA PARA EL SANEAMIENTO BÁSICO. CENTRO POBLADO LA FLORIDA, MUNICIPIO DE PEREIRA

En la cuenca media del río Otún, municipio de Pereira, Colombia, se dio inicio al fortalecimiento de la gestión comunitaria para la apropiación del servicio de alcantarillado, como aspecto clave de la sostenibilidad de las soluciones implementadas en la localidad de La Florid