El perfil afectivo/matemático de estudiantes de ciencias e ingeniería

En la investigación en educación matemática, el rendimiento se ha estudiado desde diferentes ópticas: cognitiva, social y emocional, entre otras. Este estudio analiza las creencias y actitudes de estudiantes de ingeniería y de ciencias a través de una metodología basada en la lógica fuzzy. Los resultados muestran, que a los de ingeniería les gustan más las matemáticas, presentan mayor autoestima matemática y creen que las matemáticas son importantes de un modo significativamente mayor que para los estudiantes de ciencias. No obstante, todos son conscientes de su responsabilidad en el aprendizaje de las matemáticas, y coinciden en valorar el papel del profesor, aunque no se considere un elemento influyente a nivel emocional

La invasión de los garbanzos

Congreso Universitario de Innovación Educativa En las Enseñanzas Técnicas, CUIEET (26º. 2018. Gijón

Performance degradation prediction of a low-temperature SOFC via impedance spectroscopy and CFD modelling

The present work encompasses the immediate performance characterization of a first generation LSC-based SOFC single cell by means of polarization curves, electrochemical impedance spectroscopy (EIS), the distribution relaxation times (DRT) method and equivalent circuit modeling (ECM). Besides, an endurance performance characterization based on the FCTESQA testing protocols along with EIS measurements, the aforementioned ECM and computational fluid dynamics (CFD) modelling theory has enabled to generate a time-dependent model capable of predicting performance degradation of the single cell when operating under predetermined conditions

Acrylates Polymerization on Covalent Plasma-Assisted Functionalized Graphene: A Route to Synthesize Hybrid Functional Materials

[EN] The modification of the surface properties of graphene with polymers provides a method for expanding its scope into new applications as a hybrid material. Unfortunately, the chemical inertness of graphene hinders the covalent functionalization required to build them up. Developing new strategies to enhance the graphene chemical activity for efficient and stable functionalization, while preserving its electronic properties, is a major challenge. We here devise a covalent functionalization method that is clean, reproducible, scalable, and technologically relevant for the synthesis of a large-scale, substrate-supported graphene–polymer hybrid material. In a first step, hydrogen-assisted plasma activation of p-aminophenol (p-AP) linker molecules produces their stable and covalent attachment to large-area graphene. Second, an in situ radical polymerization reaction of 2-hydroxyethyl acrylate (HEA) is carried out on the functionalized surface, leading to a graphene–polymer hybrid functional material. The functionalization with a hydrophilic and soft polymer modifies the hydrophobicity of graphene and might enhance its biocompatibility. We have characterized these hybrid materials by atomic force microscopy (AFM), X-Ray photoelectron spectroscopy (XPS) and Raman spectroscopy and studied their electrical response, confirming that the graphene/p-AP/PHEA architecture is anchored covalently by the sp3 hybridization and controlled polymerization reaction on graphene, retaining its suitable electronic properties. Among all the possibilities, we assess the proof of concept of this graphene-based hybrid platform as a humidity sensor. An enhanced sensitivity is obtained in comparison with pristine graphene and related materials. This functional nanoarchitecture and the two-step strategy open up future potential applications in sensors, biomaterials, or biotechnology fields.Funding from the innovation program under grant agreement no. 881603 (Graphene Core3-Graphene-based disruptive technologies). We acknowledge a research contract Margarita Salas financial support from Spanish “Ministerio de Ciencia, Innovación y Universidades” financed with Next Generation funds from EU. This work was supported by the project references PID2020-113142RB-C21, PID2021-125309OA-100, TED2021-129999B-C31 and TED2021-129416A-I00 funded by MCIN/AEI/10.13039/501100011033.Peer reviewe

In-situ study of the gas-phase composition and temperature of an intermediate-temperature solid oxide fuel cell anode surface fed by reformate natural gas

An innovative experimental setup is used for in-depth and in-operando characterization of solid oxide fuel cell anodic processes. This work focuses on the heterogeneous reactions taking place on a 121 cm2anode-supported cell (ASC) running with a H2, CH4, CO2, CO and steam gas mixture as a fuel, using an operating temperature of 923 K. The results have been obtained by analyzing the gas composition and temperature profiles along the anode surface in different conditions: open circuit voltage (OCV) and under two different current densities, 165 mA cmâ2and 330 mA cmâ2, corresponding to 27% and 54% of fuel utilization, respectively. The gas composition and temperature analysis results are consistent, allowing to monitor the evolution of the principal chemical and electrochemical reactions along the anode surface. A possible competition between CO2and H2O in methane internal reforming is shown under OCV condition and low current density values, leading to two different types of methane reforming: Steam Reforming and Dry Reforming. Under a current load of 40 A, the dominance of exothermic reactions leads to a more marked increase of temperature in the portion of the cell close to the inlet revealing that current density is not uniform along the anode surface

Thermal integration of a SOFC power generator and a Na–NiCl2 battery for CHP domestic application

In this study the integration of a Solid Oxide Fuel Cell (SOFC) prime mover and a high temperature electrochemical Sodium Nickel Chloride (SNC) battery as storage has been investigated. The aim is to fulfil a domestic user energy demand and to reduce the primary energy consumption in comparison with a reference conventional scenario, thereby, to enhance the total efficiency in a Î1⁄4-CHP (Combined Heat and Power) application on a yearly basis. A realistic operational sequence of the SOFC-battery integration has been calculated using simple logic conditions. Both thermal and electric integration have been considered, where the innovative thermal integration has been proposed in order to exploit the SOFC residual heat for the battery stand-by feeding. The key advantage of this system architecture is that the SOFC is operated without major load variations close to constant load, resulting in longer lifetime and thus reducing total costs of operation. The thermal integration provides additional advantages, as calculated in this study. Eventually, a comparison with alternative Î1⁄4-CHP technologies has been carried out, highlighting the potential of the system based on the SOFC. Benefits are mainly shown in terms of primary energy savings and admissible costs

Inactivation of fatty acid synthase impairs hepatocarcinogenesis driven by AKT in mice and humans

BACKGROUND & AIMS: Cumulating evidence underlines the crucial role of aberrant lipogenesis in human hepatocellular carcinoma (HCC). Here, we investigated the oncogenic potential of fatty acid synthase (FASN), the master regulator of de novo lipogenesis, in the mouse liver. METHODS: FASN was overexpressed in the mouse liver, either alone or in combination with activated N-Ras, c-Met, or SCD1, via hydrodynamic injection. Activated AKT was overexpressed via hydrodynamic injection in livers of conditional FASN or Rictor knockout mice. FASN was suppressed in human hepatoma cell lines via specific small interfering RNA. RESULTS: Overexpression of FASN, either alone or in combination with other genes associated with hepatocarcinogenesis, did not induce histological liver alterations. In contrast, genetic ablation of FASN resulted in the complete inhibition of hepatocarcinogenesis in AKT-overexpressing mice. In human HCC cell lines, FASN inactivation led to a decline in cell proliferation and a rise in apoptosis, which were paralleled by a decrease in the levels of phosphorylated/activated AKT, an event controlled by the mammalian target of rapamycin complex 2 (mTORC2). Downregulation of AKT phosphorylation/activation following FASN inactivation was associated with strong inhibition of rapamycin-insensitive companion of mTOR (Rictor), the major component of mTORC2, at post-transcriptional level. Finally, genetic ablation of Rictor impaired AKT-driven hepatocarcinogenesis in mice. CONCLUSIONS: FASN is not oncogenic per se in the mouse liver, but is necessary for AKT-driven hepatocarcinogenesis. Pharmacological blockade of FASN might be highly useful in the treatment of human HCC characterized by activation of the AKT pathway