8 research outputs found

    Modification of Nafion Membranes with Polyaniline to Reduce Methanol Permeability

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    The modification of Nafion membranes with polyaniline (PAni) has been studied as an alternative for reducing methanol crossover in direct methanol fuel cells (DMFC). The modification has been performed by directly polymerizing the PAni following two different routes: immersion (Naf-S-Y, where S mean surface and Y the number of hours exposition) and crossover (Naf-C-Y, where C means crossover). The former consist of exposing the membranes to a reactive solution containing the aniline, oxidant and catalyst; while in the latter the aniline and a solution with the oxidant and the catalyst are in different chambers separated by the membrane, thus forcing them to react inside it. The effect of the modification mechanism and the reaction times has been studied. The resulting membranes were extensively characterized by means of Fourier Transform Infrared (FTIR), ionic exchange capacity (IEC), water uptake (WU), methanol permeability and single direct methanol fuel cell performance. Chemical characterization revealed that the oxidation state of the polyaniline was in all cases emeraldine and the amount of PAni for an equivalent exposure time was bigger for the crossover route. The crossover route has proven to be more effective in decreasing the apparent methanol permeability of Nafion modified membranes up to 48% for the crossover sample with higher modification time when the polymerization is due inside the membrane such is the case of the composite Naf-C-Y membranes. The Direct Methanol Fuel Cells performances of membrane-electrode assemblies prepared with pristine Nafion and Nafion-PAni membranes were tested at 40, 60 and 80 degrees C under 2 M methanol concentration. The results are compared with those found for Nafion pristine membranes which power densities were 90, 65, 60 and 50 mW/cm(2) at 80 degrees C for Nafion, Naf-S-1, Naf-S-5 and Naf-C-2, membranes respectively.This research is in the frame of Support Program for Research and Development of the Polytechnic University of Valencia and the Ministry of Science and Innovation for funding provided through the projects: SP-ENE-20120718 and 24761, respectively.Gonzalez-Ausejo, J.; Cabedo Mas, L.; Gámez-Pérez, J.; Mollá Romano, S.; Giménez Torres, E.; Compañ Moreno, V. (2015). Modification of Nafion Membranes with Polyaniline to Reduce Methanol Permeability. Journal of The Electrochemical Society. 162(14):E325-E333. doi:10.1149/2.0521514jesSE325E3331621

    The Oncolytic Adenovirus Delta-24-RGD in Combination With ONC201 Induces a Potent Antitumor Response in Pediatric High-Grade and Diffuse Midline Glioma Models

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    BACKGROUND: Pediatric high-grade gliomas (pHGGs), including diffuse midline gliomas (DMGs), are aggressive pediatric tumors with one of the poorest prognoses. Delta-24-RGD and ONC201 have shown promising efficacy as single agents for these tumors. However, the combination of both agents has not been evaluated. METHODS: The production of functional viruses was assessed by immunoblotting and replication assays. The antitumor effect was evaluated in a panel of human and murine pHGG and DMG cell lines. RNAseq, the seahorse stress test, mitochondrial DNA content, and γH2A.X immunofluorescence were used to perform mechanistic studies. Mouse models of both diseases were used to assess the efficacy of the combination in vivo. The tumor immune microenvironment was evaluated using flow cytometry, RNAseq, and multiplexed immunofluorescence staining. RESULTS: The Delta-24-RGD/ONC201 combination did not affect the virus replication capability in human pHGG and DMG models in vitro. Cytotoxicity analysis showed that the combination treatment was either synergistic or additive. Mechanistically, the combination treatment increased nuclear DNA damage and maintained the metabolic perturbation and mitochondrial damage caused by each agent alone. Delta-24-RGD/ONC201 cotreatment extended the overall survival of mice implanted with human and murine pHGG and DMG cells, independent of H3 mutation status and location. Finally, combination treatment in murine DMG models revealed a reshaping of the tumor microenvironment to a proinflammatory phenotype. CONCLUSIONS: The Delta-24-RGD/ONC201 combination improved the efficacy compared to each agent alone in in vitro and in vivo models by potentiating nuclear DNA damage and in turn improving the antitumor (immune) response to each agent alone

    Pilot study describing the design process of an oil sump for a competition vehicle by combining additive manufacturing and carbon fibre layers

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    Formula Student is an international competition governed by the Society of Automotive Engineers (SAE) which challenges university students to design and build a racing car that will subsequently be compared against other cars from universities around the world on homologated racing circuits by non-professional drivers. This study focuses on the design, analysis and manufacturing process of a new oil sump for a Formula Student car - which involves combining a main ABS-plastic core created by an additive manufacturing (AM) printing process and a manual lay-up process with carbon fibre - in order to reduce the sloshing effect due to the movement of the oil during racing. The new oil sump and the original sump were modelled with computer-aided design (CAD) software and five computational fluid dynamics (CFD) simulations were performed to compare the sloshing effect in both designs in three driving scenarios: acceleration, braking and changing direction. The simulations showed that acceleration is not a critical situation since the new internal design of the sump was capable of delaying the immersion time of the oil pick-up pipe from 0.75 seconds to 2 seconds during braking and from 0.4 seconds to 0.8 seconds during lateral acceleration. The new design was physically manufactured and subsequently integrated into an internal combustion engine for testing for 45 minutes. During this test, the engine was started and put at 9600 RPM, so the oil worked under realistic temperature conditions (80 degrees C). It did not present any oil leak. After testing, it was disassembled and visually inspected. No failure in the inner surfaces of the oil sump was observed due to temperature. According to these results, the present research argues that the combination of AM technology (i.e., fused deposition modelling) and layers of carbon fibre is a real alternative to conventional manufacturing processes in order to create geometrically complex oil sumps that minimise the sloshing effect in competition automobiles

    CD137 and PD-L1 targeting with immunovirotherapy induces a potent and durable antitumor immune response in glioblastoma models

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    Background Glioblastoma (GBM) is a devastating primary brain tumor with a highly immunosuppressive tumor microenvironment, and treatment with oncolytic viruses (OVs) has emerged as a promising strategy for these tumors. Our group constructed a new OV named Delta-24-ACT, which was based on the Delta-24-RGD platform armed with 4-1BB ligand (4-1BBL). In this study, we evaluated the antitumor effect of Delta-24-ACT alone or in combination with an immune checkpoint inhibitor (ICI) in preclinical models of glioma. Methods The in vitro effect of Delta-24-ACT was characterized through analyses of its infectivity, replication and cytotoxicity by flow cytometry, immunofluorescence (IF) and MTS assays, respectively. The antitumor effect and therapeutic mechanism were evaluated in vivo using several immunocompetent murine glioma models. The tumor microenvironment was studied by flow cytometry, immunohistochemistry and IF. Results Delta-24-ACT was able to infect and exert a cytotoxic effect on murine and human glioma cell lines. Moreover, Delta-24-ACT expressed functional 4-1BBL that was able to costimulate T lymphocytes in vitro and in vivo. Delta-24-ACT elicited a more potent antitumor effect in GBM murine models than Delta-24-RGD, as demonstrated by significant increases in median survival and the percentage of long-term survivors. Furthermore, Delta-24-ACT modulated the tumor microenvironment, which led to lymphocyte infiltration and alteration of their immune phenotype, as ..

    CD137 and PD-L1 targeting with immunovirotherapy induces a potent and durable antitumor immune response in glioblastoma models

    No full text
    Background Glioblastoma (GBM) is a devastating primary brain tumor with a highly immunosuppressive tumor microenvironment, and treatment with oncolytic viruses (OVs) has emerged as a promising strategy for these tumors. Our group constructed a new OV named Delta-24-ACT, which was based on the Delta-24-RGD platform armed with 4-1BB ligand (4-1BBL). In this study, we evaluated the antitumor effect of Delta-24-ACT alone or in combination with an immune checkpoint inhibitor (ICI) in preclinical models of glioma. Methods The in vitro effect of Delta-24-ACT was characterized through analyses of its infectivity, replication and cytotoxicity by flow cytometry, immunofluorescence (IF) and MTS assays, respectively. The antitumor effect and therapeutic mechanism were evaluated in vivo using several immunocompetent murine glioma models. The tumor microenvironment was studied by flow cytometry, immunohistochemistry and IF. Results Delta-24-ACT was able to infect and exert a cytotoxic effect on murine and human glioma cell lines. Moreover, Delta-24-ACT expressed functional 4-1BBL that was able to costimulate T lymphocytes in vitro and in vivo. Delta-24-ACT elicited a more potent antitumor effect in GBM murine models than Delta-24-RGD, as demonstrated by significant increases in median survival and the percentage of long-term survivors. Furthermore, Delta-24-ACT modulated the tumor microenvironment, which led to lymphocyte infiltration and alteration of their immune phenotype, as ..

    Poly (lactic acid) blends: Processing, properties and applications

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