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Collagenous sprue is a rare disease of the small bowel characterized by mucosal atrophy and excessive subepithelial collagen deposition. The etiology remains unclear and the diagnosis is based upon patient's clinical picture and anatomopathological findings. Clinically, collagenous sprue is characterized by persistent diarrhoea, severe malabsorption, multiple nutrient deficiencies and progressive weight loss. Differential diagnosis includes celiac disease, which is mandatory to rule out because of their frequent association. Gluten-free diet is the first therapeutic step, but it usually is not effective. However, recent studies show high success rates with immunomodulators, mainly corticosteroids. We report the case of a patient presenting with chronic diarrhea and severe malabsorption who was diagnosed with collagenous sprue, with no response to gluten free diet, but with excellent response to budesonida.

Constructed wetlands-microbial fuel cells (CW-MFC) are an innovative technology used for simultaneous bioelectricity generation and wastewater treatment. This is possible due to the installation of macrophytes in an electrode configuration, in which electroactive microorganisms use organic substrates as biofuel. One way to improve the electrochemical performance of CW-MFCs is through the impregnation of cathodic electrocatalysts. Therefore, in this study the bioelectricity production capacity of CW-MFCs was evaluated from the oxygen reduction reaction (ORR). For this study, the concentrations 0 (CW-MFC1), 0.5 (CW-MFC2), and 1 mg/cm2 (CW-MFC3) of graphene/titanium dioxide (G/TiO2) as electrocatalyst on the cathodes were evaluated. Using the Koutecky-Levich analysis, it was determined that the ORR transfer mechanism arises via a 4-electron pathway. The electrokinetic parameters of Tafel slope, charge transfer coefficient, and exchange current density determined the efficiency of the ORR, registering 92 mV/dec, 0.93 (α), and 2.30 x10-3 mA/cm2, respectively for CW-MFC3. The highest electrochemical performance was obtained at a concentration of 1 mg/cm2 (CW-MFC3) of G/TiO2, generating 144 mW/m2 of power density, 157 Ω of internal resistance, −150 mV of anodic potential, and 383 mV of cathodic potential. The surface modification carried out on the cathodes resulted in a catalytic increase in the ORR.

Biodiesel is a mixture of saturated and unsaturated Fatty Acid Methyl Esters (FAMEs) whose composition affects the corrosion behavior of metal containers during storage. This study examines the effect of the C=C bond present in selected FAMEs (Methyl Stearate, Methyl Oleate, and Methyl Linoleate) in aluminum corrosion in the absence of oxygen. First, mass loss assays were carried out at 100, 200, and 280 °C for 1000 h using pure Methyl Stearate (MS), 5% Methyl Oleate in Methyl Stearate (MS-5% MO), and 5% Methyl Linoleate in Methyl Stearate (MS-5% ML). Next, chemical changes in FAMEs were studied using FTIR, TGA, and GC/MS. SEM/EDS analysis allowed us to inspect the aluminum surfaces and their chemical characterization. We estimated higher corrosion rates for MS assays than those of unsaturated methyl ester mixtures. In a separate set of experiments, we used electrochemical techniques (potentiodynamic polarization, linear polarization resistance, and electrochemical impedance spectroscopy) to investigate aluminum corrosion induced by thermal-degraded products from FAMEs at 100, 200, and 280 °C for 300 h able to dissolve in aqueous extracts. These electrochemical experiments revealed that the products in the aqueous extracts from the unsaturated methyl ester mixture form a passive layer on the Al surface thicker than pure MS at the corresponding degradation temperatures.

In this study, a microbial consortium isolated from an activated sludge tank of a conventional wastewater treatment plant was immobilized using sodium alginate (SA) as a support material for contaminant biodegradation in wastewater. A volume of 500 mL of activated sludge was immobilized in the SA beads (with a mass concentration of 25 g/L). The resulting SA beads were characterized, introduced into a fluidized bed reactor, fed with 1000 mL of the sample, and characterized again after the treatment process. The SA-immobilized microorganisms were tested first for degradation of organic matter (expressed as chemical oxygen demand) and total phosphorous in domestic wastewater, achieving removal efficiencies of 71% and 93%, respectively, after 12 h. Subsequently, the SA-immobilized microorganisms were tested for degradation of a basic blue 9 (BB9) textile dye in a condition that simulated textile wastewater. The efficiency of the BB9 degradation was found to be as high as 99.5% after 2 h. According to these results, SA-immobilized microorganisms were found to be an environmentally friendly and cost-effective alternative for treatment of municipal and industrial wastewater effluents.

Magnetic carbon xerogel composites with Fe3O4 nanoparticles (MNPs) prepared via co-precipitation can effectively remove arsenic (As(V) and As(III)) and fluoride ions from groundwater. The optimum conditions for the synthesis of these materials were studied, including the molar ratios of MNPs and catalyst. Carbonization and post-synthesis treatment with H2O2-induced surface modification were applied. SEM and Fe analysis revealed the presence of Fe in the materials. This study provides a promising new method for the removal of arsenic and fluoride from groundwater, with the feasibility of reusing adsorbent and magnetic separation, which could have a significant impact on public health.

Most wastewater treatment plants use activated sludge-based biological systems for this purpose. The latter must effectively remove organic matter and, at the same time, show good sedimentability. However, sometimes there is an excessive proliferation of certain bacteria, giving rise to filamentary swelling, compromising the excellent sedimentability of the sludge. In this sense, the study’s objective was to evaluate the effect of applying two different technologies, the application of low-frequency ultrasound and UV radiation. Some bench-scale experiments were performed using the bulked sludge from the secondary clarifier of a wastewater treatment facility in an industrial park (CIVAC) in Morelos, Mexico, affected by filamentous organisms. Results showed that for the UV application for two, four, and 6 min, the settleability of the mixed liquor suspended solids was not improved; on the other hand, the cavitation effect caused by the ultrasound application demonstrated effective action against the destruction of filamentous organisms. The 10 min condition showed a significant decrease in the filament integrity of the microorganisms and a significant improvement of sedimentation velocity and sludge volume index (SVI) values and settleability of the sludge, but not enough to satisfy national discharge regulations related to total suspended solids in the treated effluent. Molecular identification indicates the presence of the genera Thauera and Brevundimonas in the sludge.

Currently there is a growing concern about the presence of emerging contaminants (EC) in water bodies and their potential ecotoxicological effects. Pharmaceuticals, a type of EC, are widely distributed in the environment and their main entry is through wastewater from treatment plants, since these systems are not designed to remove EC. In this sense, the photo-Fenton process, an advanced oxidation process, has proven to be highly efficient in degrading new potentially harmful contaminants. However, this process is affected by multiple factors, which makes it necessary to implement a methodological strategy to optimize the photo-Fenton process. Within these, the Taguchi method provides robust and low-cost solutions with the least number of experiments, providing knowledge of the contribution of each of the factors studied to the response variable. In addition to the above, the Taguchi method can be coupled to a Grey relational analysis (Grey–Taguchi method), which will allow the optimization of more than one response variable at the same time. This paper discusses the parameters that affect the photo-Fenton process and the application of designs of experiments to optimize the process.

Magnetic carbon xerogels were synthesized via direct sonication to load magnetite nanoparticles in sol–gel polycondensation onto resorcinol-formaldehyde gels. The resulting organic gels were carbonized and subjected to surface modification using H2O2 and characterized using scanning electron microscopy and energy-dispersive X-ray spectroscopy. The desorption capacity was optimized using response surface methodology, with the adsorbent dose identified as the most significant quantitative factor. The kinetic adsorption was well described using the Elovich and Power equations. The regeneration capacity was evaluated over four sequential adsorption–desorption cycles, demonstrating the possibility of reusing the adsorbent and reducing the environmental impact.

Groundwater is an important source of fresh water in the world. However, the excessive extraction and increasing pollution represent a major challenge for water sustainability in Mexico. Nowadays, since water quality changes in aquifers are not noticeable, aquifer monitoring and assessment are imperious. In this study, the water quality of the Cuernavaca aquifer was evaluated using a database of 23 parameters in 4 sampling points from 2012 to 2019. The spatial behavior of water quality variables was described by using interpolation. The temporal evaluation of groundwater quality was carried out through time series. Water quality indices (WQI) were obtained in this aquifer and the WQI values suggest that the groundwater could be considered as good quality for potable use and of medium-high quality for irrigation. The chemical characteristics of the groundwater were also evaluated using Gibb, Piper, and Schoeller diagrams. Finally, with a total of 34 samples of each parameter in each sampling site, a multivariate statistical analysis was performed using a Pearson correlation and hierarchical cluster analysis. This analysis showed a correlation between hydrochemical features and groundwater quality parameters, where nitrates presented the highest number of significant correlations with other parameters. These results may be useful for the authorities to adopt planning methods to improve the sustainable development of the aquifer.

Este artículo investiga dos movimientos ciudadanos. Por una parte, la movilización que se opuso al Mall Barón en Valparaíso, y, por otra, la movilización que estuvo a favor del Mall de Castro en Chiloé. A través de una metodología cualitativa, basada en entrevistas en profundidad y análisis de fuentes, se busca conocer la vinculación de estos movimientos ciudadanos con la activación de la dimensión política del derecho de acceso al patrimonio cultural en la concepción vigente implementada en la política pública. Se reconoce que hay elementos del derecho al patrimonio cultural que no están presentes en ella, en particular la no consideración de la participación ciudadana en la toma de decisiones respecto de su propio patrimonio y tampoco el reconocimiento y la legitimación de nuevos patrimonios correspondientes a las diversas subjetividades sociales existentes al interior de una misma sociedad. Desconocerlos se transforma en un problema de sustentabilidad social que impacta en los niveles de desarrollo humano, bienestar social y en la calidad de nuestra democracia

In this study, the use of Polyvinylchloride (PVC) and High Density Polystyrene (HDPS) was demonstrated as an alternative for the adsorption of Malathion. Adsorption kinetics and isotherms were used to compare three different adsorbent materials: PVC, HDPS, and activated carbon. The adsorption capacity of PVC was three times higher than activated carbon, and a theoretical value of 96.15 mg of Malathion could be adsorbed when using only 1 g of PVC. A pseudo first-order rate constant of 1.98 (1/h) was achieved according to Lagergren kinetic model. The adsorption rate and capacity values obtained in the present study are very promising since with very little adsorbent material it is possible to obtain high removal efficiencies. Phosphorous and sulfur elements were identified through Energy Dispersive X-ray (EDX) analysis and evidenced the malathion adsorption on PVC. The characteristic spectrum of malathion was identified by the Fourier Transform Infrared (FTIR) Spectroscopy analysis. The Thermogravimetric and Differential Thermal Analysis (TG/DTA) suggested that the adsorption of malathion on the surface of the polymers was mainly determined by hydrogen bonds.

La organización social que se ha conformado en torno a la defensa del patrimonio cultural, tangible e intangible, sin duda constituye una de las transformaciones más significativas de los denominados movimientos urbanos. Este trabajo aborda una de las experiencias más significativas y paradigmáticas de este fenómeno en Chile: los movimientos de defensa patrimonial en Valparaíso. Ciudad en la cual su casco histórico fue declarado Patrimonio de la Humanidad por UNESCO, y cuya propia declaratoria reveló las contradicciones sociales y políticas en relación a su valoración y protección, lo que, paradójicamente, estimuló el fortalecimiento de movimientos patrimonialistas. Comprender los orígenes, las motivaciones, orientaciones y objetivos de éstos es el principal propósito de este artículo, y de esta manera, contribuir desde las ciencias sociales a profundizar el análisis crítico de los problemas de la cultura urbana, partiendo de la base conceptual que la ciudad y su patrimonio se ha constituido en un derecho de todos.