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Este artículo destaca el impacto y la crítica a los presupuestos teóricos de la predicción en los modelos EGDE, además de sus alcances y límites en materia de política económica realizada por los bancos centrales. Hemos elegido temas diversos para explicar los fenómenos predictivos en ciencias sociales y, principalmente, en economía, basados en la econofísica, econometría y la macroeconometría aplicados a los modelos EGDE, pero estos giran en torno al problema mente-cerebro y a la “teoría de la cognición de codificación predictiva”. Conceptualizamos sus aportes a través de problemas epistemológicos y los relacionamos con su aplicación a los modelos EGDE. Así, pretendemos enfatizar la tarea de nuestra crítica para abrir el campo de análisis de las teorías de la predicción hacia los sistemas complejos en ciencias sociales y otros debates epistémicos. Por lo tanto, se defiende la tesis de las limitaciones en la predicción bajo el concepto del cerebro como motor de predicción para dar un aporte de una posible concepción epistemológica de la predicción en ciencias naturales y sociales.

Este artículo presenta un estudio epistemológico de los fenómenos económicos basados en los modelos EGDE (Equilibrio General Dinámico y Estocástico) y la NEC (Nueva Economía Clásica). También, destaca el impacto y la crítica a los presupuestos teóricos de la predicción en los modelos EGDE, además de sus alcances y limites en materia de política económica realizada por los bancos centrales. Discutimos problemas epistemológicos de los modelos EGDE. Mostramos críticamente los modelos RANK (Modelos de Agentes Representativos Neokeynesianos), HANK (Modelos de Agentes Heterogéneos Neokeynesianos) y TANK (Modelos con Dos Agentes Neokeynesianos), como posibles alternativas para la aplicación en temas macroeconómicos. Nuestro principal análisis está basado en los modelos HANK, como posible herramienta cuantitativa de los MBA (Modelos Basados en Agentes). Así, pretendemos enfatizar la tarea de nuestra crítica para abrir el campo de análisis a los sistemas complejos en ciencias sociales y otros debates epistémicos.

Traditional aerogels lack specific functional groups for the adsorption of Pb2+, which results in a low adsorption capacity and limits the application scope. Novel porous pectin-based aerogels (PPEAs) were prepared by incorporating polyethylenimine (PEI) using ethylene glycol diglycidyl ether (EGDE) as a cross-linker for the removal of Pb2+ from water. The cross-linking mechanism, morphology, mechanical strength, thermal stability, adsorption properties, and mechanism of the aerogels were investigated. The aerogels possessed several desirable features, such as a large maximum Pb2+ adsorption capacity (373.7 mg/g, tested at pH 5.0), ultralight (as low as 63.4 mg/cm3 ), high mechanical strength (stress above 0.24 MPa at 50% strain), and easy recyclability. Meanwhile, the equilibrium adsorption data was well described by the Langmuir–Freundlich (Sips) model and the kinetic adsorption process was well fitted using the pseudo-second-order model. The donor groups, such as -NH2 , and oxygen-containing functional groups were responsible for the Pb2+ adsorption, which was confirmed by the FTIR and XPS analysis. The excellent characteristics mean that PPEAs are highly effective adsorbents in the remediation of lead-containing wastewater. [ABSTRACT FROM AUTHOR]

Traditional aerogels lack specific functional groups for the adsorption of Pb2+, which results in a low adsorption capacity and limits the application scope. Novel porous pectin-based aerogels (PPEAs) were prepared by incorporating polyethylenimine (PEI) using ethylene glycol diglycidyl ether (EGDE) as a cross-linker for the removal of Pb2+ from water. The cross-linking mechanism, morphology, mechanical strength, thermal stability, adsorption properties, and mechanism of the aerogels were investigated. The aerogels possessed several desirable features, such as a large maximum Pb2+ adsorption capacity (373.7 mg/g, tested at pH 5.0), ultralight (as low as 63.4 mg/cm3), high mechanical strength (stress above 0.24 MPa at 50% strain), and easy recyclability. Meanwhile, the equilibrium adsorption data was well described by the Langmuir–Freundlich (Sips) model and the kinetic adsorption process was well fitted using the pseudo-second-order model. The donor groups, such as -NH2, and oxygen-containing functional groups were responsible for the Pb2+ adsorption, which was confirmed by the FTIR and XPS analysis. The excellent characteristics mean that PPEAs are highly effective adsorbents in the remediation of lead-containing wastewater.

The aims of this research is to synthesize a chitosan derivative insoluble in acidic aqueous medium and that has high adsorption capacity for Pb(II) ions by cross-linking and grafting. Cross-linking and grafting were done using ethylene glycol diglycidyl ether (EGDE) and chloroacetic acid, respectively. The modified chitosan was characterized using FTIR spectrophotometer, XRD and TG-DTA. Chitosan and Chit-EGDE-Acetate was applied as adsorbent of Pb(II) ions in a batch system. The concentration of Pb(II) in adsorption medium was quantified using AAS. The result showed that the adsorption was optimum at pH 5, contact time of 200 min for chitosan and 300 min for Chit-EGDE-Acetate. Adsorption of Pb(II) ions on both adsorbents followed pseudo second order kinetic equation. Adsorption of Pb(II) ions on chitosan followed Freundlich isotherm while that on Chit-EGDE-Acetate followed the Langmuir adsorption isotherm. The adsorption capacity of Chit-EGDE-Acetate for Pb(II) ions was 200.0 mg L-1 while that for chitosan was 166.7 mg L-1. Interaction type of Pb(II) ions on adsorbent was determined by sequential desorption.

The objective of this study was to improve performance of the soybean meal-based adhesive by an ethylene glycol diglycidyl ether (EGDE) and diethylenetriamine (DETA). Three-ply plywood was fabricated to measure wet shear strength. The functional groups, cross section, crystallinity, thermal behavior, and physical properties of the resultant adhesives were characterized in detail. Results show that DETA reacted with EGDE to form a long chain structure with epoxy groups, which cross-linked the soy protein molecules to form a denser cured adhesive layer to improve the water resistance of the resultant adhesive. In addition, the long chain structure formed an interpenetrating network with the soy protein molecules, which further improved the water resistance of the adhesive. Incorporating EGDE/DETA, the wet shear strength of the plywood bonded by the resultant adhesive was improved by 30.7% to 1.15 MPa, which met the interior use plywood requirement. Additionally, compared with the soybean meal-based control adhesives, the viscosity of the cured adhesive decreased by 39.4–50.3%, that made the resultant adhesive practical for plywood industrial application. [ABSTRACT FROM AUTHOR]

This project adopts the oxygen low temperature plasma to pre-process the wool fiber, thus giving it very hydrophilic effect, then uses ethylene glycidyl ether (EGDE) as a cross linking agent to graft collagen to the surface of cashmere, hence to prepare collagen-wool fiber. Fiber weight gain shows that collagen has been fixed to the wool surface. The change of ultraviolet and infrared spectrum and scanning electron microscopy (SEM) determines that there was bridging reaction of EGDE between fibers and collagen. Collagen modified wool fiber not only enjoys better wet absorption but dye ability than that of untreated fibers. In addition, the fixation of collagen improves to some extent the breaking strength and breaking elongation of the fiber. [ABSTRACT FROM AUTHOR]

Traditional aerogels lack specific functional groups for the adsorption of Pb 2+ , which results in a low adsorption capacity and limits the application scope. Novel porous pectin-based aerogels (PPEAs) were prepared by incorporating polyethylenimine (PEI) using ethylene glycol diglycidyl ether (EGDE) as a cross-linker for the removal of Pb 2+ from water. The cross-linking mechanism, morphology, mechanical strength, thermal stability, adsorption properties, and mechanism of the aerogels were investigated. The aerogels possessed several desirable features, such as a large maximum Pb 2+ adsorption capacity (373.7 mg/g, tested at pH 5.0), ultralight (as low as 63.4 mg/cm 3 ), high mechanical strength (stress above 0.24 MPa at 50% strain), and easy recyclability. Meanwhile, the equilibrium adsorption data was well described by the Langmuir-Freundlich (Sips) model and the kinetic adsorption process was well fitted using the pseudo-second-order model. The donor groups, such as -NH 2 , and oxygen-containing functional groups were responsible for the Pb 2+ adsorption, which was confirmed by the FTIR and XPS analysis. The excellent characteristics mean that PPEAs are highly effective adsorbents in the remediation of lead-containing wastewater.

Listeria monocytogenes , the causative agent of the serious foodborne disease listeriosis, can rapidly adapt to a wide range of environmental stresses, including visible light. This study shows that exposure of the L. monocytogenes EGDe strain to low-intensity, broad-spectrum visible light inhibited bacterial growth and caused altered multicellular behavior during growth on semisolid agar compared to when the bacteria were grown in complete darkness. These light-dependent changes were observed regardless of the presence of the blue light receptor (Lmo0799) and the stressosome regulator sigma B (SigB), which have been suggested to be important for the ability of L. monocytogenes to respond to blue light. A genome-wide transcriptional analysis revealed that exposure of L. monocytogenes EGDe to broad-spectrum visible light caused altered expression of 2,409 genes belonging to 18 metabolic pathways compared to bacteria grown in darkness. The light-dependent differentially expressed genes are involved in functions such as glycan metabolism, cell wall synthesis, chemotaxis, flagellar synthesis, and resistance to oxidative stress. Exposure to light conferred reduced bacterial motility in semisolid agar, which correlates well with the light-dependent reduction in transcript levels of flagellar and chemotaxis genes. Similar light-induced reduction in growth and motility was also observed in two different L. monocytogenes food isolates, suggesting that these responses are typical for L. monocytogenes Together, the results show that even relatively small doses of broad-spectrum visible light cause genome-wide transcriptional changes, reduced growth, and motility in L. monocytogenes IMPORTANCE Despite major efforts to control L. monocytogenes , this pathogen remains a major problem for the food industry, where it poses a continuous risk of food contamination. The ability of L. monocytogenes to sense and adapt to different stressors in the environment enables it to persist in many different niches, including food production facilities and in food products. The present study shows that exposure of L. monocytogenes to low-intensity broad-spectrum visible light reduces its growth and motility and alters its multicellular behavior. Light exposure also caused genome-wide changes in transcript levels, affecting multiple metabolic pathways, which are likely to influence the bacterial physiology and lifestyle. In practical terms, the data presented in this study suggest that broad-spectrum visible light is an important environmental variable to consider as a strategy to improve food safety by reducing L. monocytogenes contamination in food production environments., (Copyright © 2019 American Society for Microbiology.)

Novel hydrogel beads having molecular adsorption abilities were prepared from carboxymethylcellulose sodium salt (CMC) and β-cyclodextrin (β-CD) by suspension crosslinking, using ethylene glycol diglycidyl ether (EGDE) in basic medium as a crosslinking agent. FTIR and solid-state NMR spectroscopic analysis revealed that the amount of incorporated β-CD and crosslinking densities within the hydrogel bead structures are strongly dependent on the molar feed ratio of β-CD to CMC during preparation. The hydrogel beads showed water-swelling capacities of 70-200 mL/g-polymer, with decreases in capacity associated with increased amounts of β-CD incorporated in the gel structure. The hydrogel beads also showed a high adsorption capacity toward bisphenol A (BPA) in water. Batch BPA-adsorption experiments were analyzed employing Langmuir isotherm models; hydrogel bead adsorption isotherms for BPA could be fitted to the Langmuir model. The maximum BPA-adsorption among the prepared series of hydrogel beads amounted to 167 μmol g(-1)., (Copyright © 2013 Elsevier Ltd. All rights reserved.)

Polysaccharides are gaining increasing attention as components of stimuli-responsive drug delivery systems, particularly since they can be obtained in a well characterized and reproducible way from the natural sources. Ionic polysaccharides can be readily crosslinked to render hydrogel networks sensitive to a variety of internal and external variables, and thus suitable for switching drug release on-off through diverse mechanisms. Hybrids, composites and grafted polymers can reinforce the responsiveness and widen the range of stimuli to which polysaccharide-based systems can respond. This review analyzes the state of the art of crosslinked ionic polysaccharides as components of delivery systems that can regulate drug release as a function of changes in pH, ion nature and concentration, electric and magnetic field intensity, light wavelength, temperature, redox potential, and certain molecules (enzymes, illness markers, and so on). Examples of specific applications are provided. The information compiled demonstrates that crosslinked networks of ionic polysaccharides are suitable building blocks for developing advanced externally activated and feed-back modulated drug delivery systems., (Copyright © 2013 Elsevier B.V. All rights reserved.)