Synthesis and Characterization of Aluminophosphates Type-5 and 36 Doubly Modified with Si and Zn and Its Catalytic Application in the Reaction of Methanol to Hydrocarbons (MTH)

This paper presents a study of the synthesis of AlPO4-5 and AlPO4-36 materials doubly substituted by Si and Zn, as acid function and aromatizing function, respectively. The physicochemical properties of the zeotypes were studied by XRD, adsorption of N2, Temperature Programmed Desorption with NH3, 31P MAS NMR and SEM. The incorporation of Zn and Si has shown an important effect on the acidic, textural and morphological properties of the samples. The particle size has a significant effect on the catalytic activity in the reaction of methanol to hydrocarbons in terms of methanol conversion and selectivity. It was observed that as the particle size decreases, the methanol conversion increases causing the catalyst to deactivate in a shorter time. The incorporation of Zn improved the selectivity to total aromatics by the aromatizing effect of Zn. The SAPO-5 (S5) material having a smaller particle size showed complete conversions of methanol. In contrast, the ZnAPO-5 (Z5) material showed low conversions but a high selectivity to total aromatics (41%). On the other hand, the material S36-2 presented a high selectivity to aromatics (58%) due to the high amount of Zn and Si. Both metals provided a certain acidic character to the materials

Antitumor Therapy under Hypoxic Microenvironment by the Combination of 2-Methoxyestradiol and Sodium Dichloroacetate on Human Non-Small-Cell Lung Cancer

A hypoxic microenvironment is a hallmark in different types of tumors; this phenomenon participates in a metabolic alteration that confers resistance to treatments. Because of this, it was proposed that a combination of 2-methoxyestradiol (2-ME) and sodium dichloroacetate (DCA) could reduce this alteration, preventing proliferation through the reactivation of aerobic metabolism in lung adenocarcinoma cell line (A549). A549 cells were cultured in a hypoxic chamber at 1% O2 for 72 hours to determine the effect of this combination on growth, migration, and expression of hypoxia-inducible factors (HIFs) by immunofluorescence. The effect in the metabolism was evaluated by the determination of glucose/glutamine consumption and the lactate/glutamate production. The treatment of 2-ME (10 μM) in combination with DCA (40 mM) under hypoxic conditions showed an inhibitory effect on growth and migration. Notably, this reduction could be attributed to 2-ME, while DCA had a predominant effect on metabolic activity. Moreover, this combination decreases the signaling of HIF-3α and partially HIF-1α but not HIF-2α. The results of this study highlight the antitumor activity of the combination of 2-ME 10 μl/DCA 40 mM, even in hypoxic conditions

Administración pública y gobernanza en la segunda década del siglo XXI

La administración pública constituye una de las ciencias sociales que están en constante transformación y una de las que se encuentran íntimamente vinculadas al contexto regional, nacional y mundial, así lo constatan los cambios que ha manifestado en las tres últimas décadas, tanto en el plano nacional como en el continental. En ese lapso hemos sido testigos de la irrupción y el desarrollo de conceptos, enfoques y campos e conocimiento, tales cómo las políticas públicas o ciencias de políticas, la nueva gestión pública, el neoinstitucionalismo y recientemente el de la gobernanza, para citar a los más visibles; todos, sin embargo, indisolublemente asociados a la Administración Pública, ya sea desde una perspectiva disciplinaria o desde su acción como brazo ejecutor del Estado