Localisation of iron and zinc in grain of biofortified wheat

Theodora Stewart Paul Anthony Sharp Govindan Velu Malcolm Hawkesford (2022)

Article

Wheat Grain Micronutrients LA-ICP-MS Localization CIENCIAS AGROPECUARIAS Y BIOTECNOLOGÍA BIOFORTIFICATION IRON TRACE ELEMENTS WHEAT ZINC

Effect of mixed liquor volatile suspended solids on membrane fouling during short and long-term operation of membrane bioreactor

EDSON BALTAZAR ESTRADA ARRIAGA PETIA MIJAYLOVA NACHEVA LILIANA GARCIA SANCHEZ (2015)

The aim of this study was to examine the impact of different Mixed Liquor Volatile Suspended Solids (MLVSS) concentrations on membrane fouling, in a submerged Membrane Bioreactor (MBR) at short and long-term MBR operation for wastewater treatment. Three laboratory-scale in a submerged MBR system were operated under critical flux, sub-critical flux, and an intermittent suction time and backwashing conditions. At short-term MBR operation with mixed liquors of 4,200 and 6,150 mg MLVSS L-1, the hydraulic resistance of membranes followed a same trajectory with averages of 5.0E+12 m-1, whereas for 7,940 mg MLVSS L-1, a high resistance of up to 1.7E+13 m-1 was obtained. The result showed that high biomass concentrations decreased to permeability due to a bio-layer formed in the membrane surface and high Extracellular Polymeric Substance.

Article

Biorreactor de membrana Saturación de la membrana Sólidos suspendidos volátiles Sustancias poliméricas extracelulares BIOLOGÍA Y QUÍMICA

Metabolites Profile of Extracts and Fractions of Erythroxylum mexicanum Kunth by UHPLC-QTOF-MS/MS and its Antibacterial, Cytotoxic and Nitric Oxide Inhibitory Activities

LAURA PATRICIA ALVAREZ BERBER MARIA DE LOS ANGELES RAMIREZ CISNEROS (2024)

The present study shows the untargeted metabolite profiling and in vitro antibacterial, cytotoxic, and nitric oxide (NO) inhibitory activities of the methanolic leaves extract (MLE) and methanolic stem extract (MSE) of Erythroxylum mexicanum, as well as the fractions from MSE. Using ultra-high performance liquid chromatography/quadrupole time-of-flight tandem mass spectrometry (UHPLC-QTOF-MS/MS), a total of 70 metabolites were identified; mainly alkaloids in the MLE, while the MSE showed a high abundance of diterpenoids. The MSE fractions exhibited differential activity against Gram-positive bacteria. Notably, the hexane fraction (HSF) against Streptococcus pyogenes ATCC 19615 (MIC=62.5 µg/mL) exhibited a bactericidal effect. The MSE fractions exhibited cytotoxicity against all cancer cell lines tested, with selectivity towards them compared to a noncancerous cell line. Particularly, the HSF and chloroform fraction (CSF) showed the highest cytotoxicity against prostate cancer (PC-3) cells, with IC50 values of 19.9 and 18.1 µg/mL and selectivity indexes of 3.8 and 4.2, respectively. Both the HSF and ethyl acetate (EASF) fractions of the MSE inhibited NO production in RAW 264.7 macrophages, with NO production percentages of 50.0% and 51.7%, respectively, at a concentration of 30 µg/mL. These results indicated that E. mexicanum can be a source of antibacterial, cytotoxic, and anti-inflammatory metabolites.

Article

BIOLOGÍA Y QUÍMICA QUÍMICA MS analysis • diterpenoids • biological activities

Efecto de los sólidos suspendidos volátiles del licor mezclado en el ensuciamiento de las membranas durante la operación de un bioreactor con membranas a corto y largo plazo

Effect of mixed liquor volatile suspended solids on membrane fouling during short and long-ter operation of membrane bioreactor

EDSON BALTAZAR ESTRADA ARRIAGA Petia Mijaylova Nacheva LILIANA GARCIA SANCHEZ (2015)

El objetivo del estudio fue examinar el impacto de diferentes concentraciones de sólidos suspendidos volátiles del licor mezclado en el ensuciamiento de las membranas en un bio-reactor con membranas sumergidas (BRMS)en periodos cortos y largos de operación durante el tratamiento del agua residual. Tres BRMS a escala laboratorio fueron operados bajo condiciones críticas, sub-críticas y condiciones de succión intermitente y retrolavados. En cortos tiempos de operación de los BRMS con concentraciones de licor mezclado de 4,200 y 6,150 mg SSVLM L-1, la resistencia hidráulica de las membranas se comportó de manera similar con un promedio de 5.0E+12 m-1, mientras para una concentración de 7,940 mg SSVLM L-1, su obtuvo una alta resistencia con valores de 1.7E+13 m-1. Los resultados mostraron que con concentraciones altas de biomasa la permeabilidad de las membranas disminuye debido a la formación de una biopelícula en la superficie de las membranas y a la presencia de Sustancia Poliméricas Extracelulares (SPE).

The aim of this study was to examine the impact of different Mixed Liquor Volatile Suspended Solids (MLVSS) concentrations on membrane fouling, in a submerged Membrane Bioreactor (MBR) at short and long-term MBR operation for wastewater treatment. Three laboratory-scale in a submerged MBR system were operated under critical flux, sub-critical flux, and an intermittent suction time and backwashing conditions. At short-term MBR operation with mixed liquors of 4,200 and 6,150 mg MLVSS L-1, the hydraulic resistance of membranes followed a same trajectory with averages of 5.0E+12 m-1, whereas for 7,940 mg MLVSS L-1, a high resistance of up to 1.7E+13 m-1 was obtained. The result showed that high biomass concentrations decreased to permeability due to a bio-layer formed in the membrane surface and high Extracellular Polymeric Substance (EPS).

Article

Biorreactores Sólidos suspendidos volátiles INGENIERÍA Y TECNOLOGÍA

Stability of FeVO4-II under Pressure: A First-Principles Study

PRICILA BETBIRAI ROMERO VAZQUEZ SINHUE LOPEZ MORENO Daniel Errandonea (2022)

"In this work, we report first-principles calculations to study FeVO4 in the CrVO4-type (phase II) structure under pressure. Total-energy calculations were performed in order to analyze the structural parameters, the electronic, elastic, mechanical, and vibrational properties of FeVO4-II up to 9.6 GPa for the first time. We found a good agreement in the structural parameters with the experimental results available in the literature. The electronic structure analysis was complemented with results obtained from the Laplacian of the charge density at the bond critical points within the Quantum Theory of Atoms in Molecules methodology. Our findings from the elastic, mechanic, and vibrational properties were correlated to determine the elastic and dynamic stability of FeVO4-II under pressure. Calculations suggest that beyond the maximum pressure covered by our study, this phase could undergo a phase transition to a wolframite-type structure, such as in CrVO4 and InVO4."

Article

FeVO4 under pressure CrVO4-type structure First-principles Mechanical properties Vibrational properties Electronic properties CIENCIAS FÍSICO MATEMÁTICAS Y CIENCIAS DE LA TIERRA FÍSICA FÍSICA DEL ESTADO SÓLIDO CRISTALOGRAFÍA CRISTALOGRAFÍA

Modelado y acoplamiento de la conductividad eléctrica e hidráulica a partir de tomografía de rocas

Modeling and coupling of electrical and hydraulic conductivity from rock tomography

Miguel Ángel Martínez Rodríguez (2022)

En este trabajo se emplearon técnicas de modelado numérico para simular el flujo de corriente eléctrica y de fluido a través de medios porosos con el fin de determinar el factor de resistividad y la permeabilidad, así como la distribución de los campos de densidad de corriente eléctrica y velocidad de flujo. Para el modelado de flujo eléctrico se desarrolló un algoritmo basado en diferencias finitas, mientras que para el modelado hidráulico se empleó una librería reportada en la literatura, basada en el método de redes de Boltzmann. En ambos esquemas de modelado se establecieron condiciones en la frontera poro-grano para modelar los procesos físicos exclusivamente en el espacio poroso. Los valores estimados de factor de resistividad y de permeabilidad, así como la porosidad, se emplearon para estudiar las correlaciones entre estas propiedades a través de relaciones petrofísicas. Para esto, se propuso una expresión que relaciona la permeabilidad y la porosidad y, empleando una relación existente entre el factor de resistividad y la porosidad, se propuso también una relación directa entre la permeabilidad y el factor de resistividad. Las relaciones propuestas fueron aplicadas a los valores numéricos obtenidos para paquetes de esferas generados numéricamente y se encontró que se ajustan mejor a los datos en comparación con las relaciones más comúnmente utilizadas, especialmente para porosidades altas. Se mostró también que estas relaciones petrofísicas toman la forma de las relaciones más comunes conocidas cuando se trata con porosidades bajas. Valores obtenidos de imágenes digitales de un paquete de esferas sintético y una muestra de dolomita mostraron que las expresiones para porosidades bajas son suficientes para ajustar datos de medios porosos con porosidades menores a un valor entre 0.3 y 0.4. Finalmente, se analizaron el factor de resistividad, la permeabilidad, las relaciones petrofísicas, y las distribuciones espaciales y estadísticas de los campos vectoriales de flujo se analizaron para comparar los fenómenos de transporte eléctrico e hidráulico, encontrando que algunos factores, como la porosidad efectiva, son importantes en ambos fenómenos de flujo; mientras que otros, como la adherencia del fluido a las paredes del poro, son particularmente relevantes para el flujo hidráulico.

In this work, numerical modeling techniques were used to simulate the flow of electric current and fluid through porous media in order to determine the resistivity factor and permeability, as well as the distribution of electric current density and flow velocity fields. For electric flow modeling, an algorithm based on finite differences was developed, while for hydraulic modeling, a library reported in the literature, based on lattice Boltzmann method, was used. In both modeling schemes, pore-grain boundary conditions were established to model the physical processes exclusively in the pore space. The estimated values of resistivity factor and permeability, as well as porosity, were used to study the correlations between these properties through petrophysical relationships. An expression relating permeability and porosity was proposed and, using an existing relationship between the resistivity factor and the porosity, a direct relation between permeability and resistivity factor was also proposed. The proposed relations were applied to data obtained for numerically generated sphere packs and were found to fit the data better than the most commonly used relationships, especially for high porosities. It was also shown that these petrophysical relationships take the form of the most common relationships known when dealing with low porosities. Modeling data on digital images of a synthetic sphere pack and a dolomite sample showed that the expressions for low porosities are sufficient to fit data from porous media with porosities lower than 0.3 to 0.4. Finally, resistivity factors, permeabilities, petrophysical relationships, and spatial and statistical distributions of flow vector fields were analyzed to compare electrical and hydraulic transport phenomena, finding that some factors, such as the effective porosity, are important in both flow phenomena; whereas some other, such as the pore-wall adherence, are particularly relevant to hidraulic flux.

Master thesis

Física de rocas, modelado numérico, relaciones petrofísicas, fenómenos de transporte, factor de resistividad, permeabilidad, porosidad, tomografía de rocas, campos vectoriales, distribución estadística Rock physics, numerical modelling, petrophysical relations, transport phenomena, resistivity factor, permeability, porosity, rock tomography, vector fields, statistical distribution CIENCIAS FÍSICO MATEMÁTICAS Y CIENCIAS DE LA TIERRA CIENCIAS DE LA TIERRA Y DEL ESPACIO GEOFÍSICA GEOFÍSICA DE LA MASA SÓLIDA TERRESTRE GEOFÍSICA DE LA MASA SÓLIDA TERRESTRE