35 research outputs found

    Propuesta para abordar la educación emocional en la etapa de Educación Infantil en el centro escolar San Francisco de Asís, Valladolid

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    El presente Trabajo de Fin de Grado aborda la problemática de la gestión emocional en el alumnado de Educación Infantil. Ante esta situación, se plantea realizar una propuesta didáctica compuesta de ocho actividades que permita obtener diferentes soluciones ante esta situación, de esta manera los alumnos no tendrán solo una, sino varias alternativas cuando se encuentren en una situación de esta índole. Esta propuesta didáctica ha sido diseñada para aplicarse en toda la etapa de Educación Infantil, pero finalmente se ha llevado a cabo en el aula de 2º B de Educación Infantil del colegio San Francisco de Asís, Valladolid con alumnos de entre 4 y 5 años de edad. Esta propuesta incluye desde actividades creativas hasta motrices. Su finalidad principal es ayudar a los alumnos a que conozcan los diversos tipos de emociones que existen, así como a aprender a gestionarlas. Su puesta en práctica se realizó durante el periodo de prácticas perteneciente al Prácticum II, la estancia en el centro fueron tres meses, pero esta propuesta se llevó a cabo durante el tercer trimestre en el mes de Mayo. Pese a no haber podido poner en práctica la programación didáctica en su totalidad, fueron suficiente las cinco actividades realizadas para obtener buenos resultados, los alumnos comprendieron a la perfección lo que se les quería transmitir y se cumplieron todos los objetivos propuestos. El aprendizaje tanto para ellos como para la alumna en prácticas que lo llevo a cabo fue muy enriquecedor.This end-of-degree project addresses the issue of emotional management in Early Childhood Education students. To address this situation, a didactic proposal consisting of eight activities has been developed to provide different solutions to this situation, so that students will not have just one, but several alternatives when faced with such situations. This didactic proposal has been designed to be applied throughout the entire Early Childhood Education stage, but it was finally carried out in the classroom of 2nd B of Early Childhood Education at the San Francisco de Asis school in Valladolid with students between 4 and 5 years old. This proposal includes both creative and motor activities. Its main purpose is to help students understand the various types of emotions that exist, as well as to learn how to manage them. Its implementation was carried out during the practical period belonging to Practicum II. The stay in the center was three months, but this proposal was carried out during the third trimester in May. Despite not being able to fully implement the didactic programming, the five activities carried out were sufficient to obtain reliable results. The students fully understood what was being conveyed to them and all proposed aims were achieved. The learning experience for both the students and the practicing student who carried it out was very enriching.Departamento de PsicologíaGrado en Educación Infanti

    Effect of temperature on particle shape, size, and polycrystallinity of Nd-Fe-B powders obtained by hydrogen decrepitation

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    This work presents a detailed study of hydrogen decrepitation (HD) to obtain monocrystalline Nd-Fe-B powder. The effect of decrepitation temperature has been investigated to optimize both particle size and shape. Differential scanning calorimetry was applied to analyze the hydrogenation kinetics of Nd2Fe14B and Nd-rich phases in the range of 25 to 300 C. Thermogravimetry and X-ray diffraction allowed determining the hydrogen absorption of the whole alloy and the matrix phase, respectively. While scanning electron microscopy (SEM) was used to visualize particle shape and size, dynamic image analysis was applied to evaluate quantitatively these properties. The high monocrystallinity of the powder was confirmed by electron backscattering diffraction. The partial pressure of hydrogen required to initiate the hydrogenation reactions decreases when the temperature increases. The hydrogen absorbed by the whole alloy and, in particular, by the Nd2Fe14B phase decreases with temperature. Below 150 C, the hydrogen absorbed by the Nd2Fe14B phase produces a significant transgranular cracking that is undesirable for particle shape. At 300 C, the fast and limited absorption of hydrogen by the Nd-rich phase causes insufficient intergranular fracture and, hence, polycrystallinity. Between 150 and 300 C, the controlled fragmentation resulted in monocrystalline particles with a more equiaxial shape, which is a suitable precursor to develop anisotropic ultrafine powders by the hydrogenation, disproportionation, desorption, recombination (HDDR) process

    Coercivity and Magnetic Anisotropy of (Fe0.76Si0.09B0.10P0.05)97.5Nb2.0Cu0.5 Amorphous and Nanocrystalline Alloy Produced by Gas Atomization Process

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    We present the evolution of magnetic anisotropy obtained from the magnetization curve of (Fe0.76Si0.09B0.10P0.05)97.5Nb2.0Cu0.5 amorphous and nanocrystalline alloy produced by a gas atomization process. The material obtained by this process is a powder exhibiting amorphous character in the as-atomized state. Heat treatment at 480 °C provokes structural relaxation, while annealing the powder at 530 °C for 30 and 60 min develops a fine nanocrystalline structure. Magnetic anisotropy distribution is explained by considering dipolar effects and the modified random anisotropy model.Author Kenny L. Alvarez thanks Becas Chile (CONICYT) for financial support. The authors thank SGIker of UPV/EHU for technical and human support. This work was supported by the European Commission (ERDF and ESF programs). Authors M. Ipatov, L. Domínguez and J. Gonzalez acknowledge the University of the Basque Country for the support under the scheme “Ayudas a Grupos Consolidados” (Ref. PPG17/35)

    Nuevas metodologías docentes de carácter multidisciplinar en el área de ciencia y tecnología de alimentos

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    La puesta en marcha del plan de estudios del Grado en Nutrición Humana y Dietética en la Universidad de Alicante exigió del profesorado implicado en la docencia en el área de Ciencia y Tecnología de Alimentos de un gran esfuerzo de adaptación a las necesidades de un alumnado de procedencia heterogénea y con un nivel de formación previa muy variable. La puesta en marcha de la nueva guía docente y la evaluación crítica y continuada de las nuevas competencias, metodologías y estrategias docentes se hace necesaria considerando la dualidad del proceso enseñanza-aprendizaje, desde el punto de vista del profesorado y del alumnado. Los conceptos básicos de la asignatura han sido cuidadosamente revisados y comprenden las competencias necesarias en el área de Ciencia y Tecnología de Alimentos que cualquier Graduado en Nutrición Humana y Dietética debe manejar para el desarrollo de su carrera profesional. Se han realizado actividades conjuntas entre el profesorado, el alumnado y profesionales externos que ya concluyeron sus estudios, capaces de dar una visión con la perspectiva necesaria para poder acomodar los contenidos y las metodologías docentes a lo que se requiere por parte de la sociedad en lo referente a los futuros Graduados en sus conocimientos científicos

    Development of anisotropic Nd-Fe-B powder from isotropic gas atomized powder

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    This work presents an innovative approach to obtain anisotropic Nd-Fe-B powder from isotropic gas atomized powder. The new process was developed using a ternary Nd-Fe-B alloy, without the requirement for additional heavy rare earth or other critical raw materials. It comprises the following steps: (a) gas atomization to produce a polycrystalline isotropic powder; (b) annealing at high temperature to induce grain growth; (c) hydrogen decrepitation to obtain a monocrystalline powder; and (d) hydrogenation-disproportionation-desorption-recombination to obtain the final ultrafine anisotropic particles. The final particle shape is polygonal, which should improve the injection molding characteristics of current powder. The final powder exhibits both high remanence (0.97 T) and coercivity (1354 kA/m) for laboratory batch sizes, which is a result of its anisotropic ultrafine microstructure. Thus, gas atomization is considered a feasible alternative to casting methods as a first step to produce powders for anisotropic bonded magnet

    Designing for Shape Memory in Additive Manufacturing of Cu–Al–Ni Shape Memory Alloy Processed by Laser Powder Bed Fusion

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    Shape memory alloys (SMAs) are functional materials that are being applied in practically all industries, from aerospace to biomedical sectors, and at present the scientific and technologic communities are looking to gain the advantages offered by the new processing technologies of additive manufacturing (AM). However, the use of AM to produce functional materials, like SMAs, constitutes a real challenge due to the particularly well controlled microstructure required to exhibit the functional property of shape memory. In the present work, the design of the complete AM processing route, from powder atomization to laser powder bed fusion for AM and hot isostatic pressing (HIP), is approached for Cu–Al–Ni SMAs. The microstructure of the different processing states is characterized in relationship with the processing parameters. The thermal martensitic transformation, responsible for the functional properties, is analyzed in a comparative way for each one of the different processed samples. The present results demonstrate that a final post–processing thermal treatment to control the microstructure is crucial to obtain the expected functional properties. Finally, it is demonstrated that using the designed processing route of laser powder bed fusion followed by a post–processing HIP and a final specific thermal treatment, a satisfactory shape memory behavior can be obtained in Cu–Al–Ni SMAs, paving the road for further applications.This research was supported by the Industry Department of the Basque Government through the ELKARTEK–CEMAP (KK–2020/00047) project, as well as from the GIU–17/071 from the University of the Basque Country UPV/EHU. Financial support was also received from the Spanish Ministry of Economy and Competitiveness, MINECO, through the project MAT2017-84069P. This work made use of the facilities from the Electronic Microscopy and Material Microanalysis Service of the SGIKER from the UPV/EHU. M.P.-C. acknowledges the pre–doctoral grant (PRE_2019_2_0268) from the Education Department of the Basque Country. J.F.G.-C. thanks the post–doctoral grant (ESPDOC18/37) from the UPV/EHU

    Additive Manufacturing of Fe-Mn-Si-Based Shape Memory Alloys: State of the Art, Challenges and Opportunities

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    Additive manufacturing (AM) constitutes the new paradigm in materials processing and its use on metals and alloys opens new unforeseen possibilities, but is facing several challenges regarding the design of the microstructure, which is particularly awkward in the case of functional materials, like shape memory alloys (SMA), as they require a robust microstructure to withstand the constraints appearing during their shape change. In the present work, the attention is focused on the AM of the important Fe-Mn-Si-based SMA family, which is attracting a great technological interest in many industrial sectors. Initially, an overview on the design concepts of this SMA family is offered, with special emphasis to the problems arising during AM. Then, such concepts are considered in order to experimentally develop the AM production of the Fe-20Mn-6Si-9Cr-5Ni (wt%) SMA through laser powder bed fusion (LPBF). The complete methodology is approached, from the gas atomization of powders to the LPBF production and the final thermal treatments to functionalize the SMA. The microstructure is characterized by scanning and transmission electron microscopy after each step of the processing route. The reversibility of the ε martensitic transformation and its evolution on cycling are studied by internal friction and electron microscopy. An outstanding 14% of fully reversible thermal transformation of ε martensite is obtained. The present results show that, in spite of the still remaining challenges, AM by LPBF offers a good approach to produce this family of Fe-Mn-Si-based SMA, opening new opportunities for its applications.This research was supported by the Industry Department of the Basque Government through the ELKARTEK-MINERVA (KK-2022/000082) project, and also from the GIU-021/24 from the University of the Basque Country UPV/EHU. This work made use of the electron microscopes installed at the General Service of Electron Microscopy of Materials, of the SGIKER—UPV/EHU, and the Zeiss at LORTEK technology center. Lucía Del-Río acknowledges the Pre-Doctoral grant (PRE_2022_1_0109) from the Education Department of the Basque Government

    Internal friction associated with ε martensite in shape memory steels produced by casting route and through additive manufacturing: Influence of thermal cycling on the martensitic transformation

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    Among the different families of shape memory alloys (SMA), the Fe-Mn-Si-Cr-Ni alloys have attracted a renewed interest because of its low cost, high corrosion resistance and high recovery strength during the shape memory effect, and the new technologies of additive manufacturing offer unforeseen possibilities for this family of SMA. In the present work, the reversible gamma - epsilon martensitic transformation (MT), responsible for the shape memory effect, is studied in two Fe-Mn-Si-Cr-Ni alloys with high (20.2 wt%) and low (15.8 wt%) Mn content, produced by the conventional route of casting and rolling, in comparison with the MT in another similar alloy, with intermediate Mn content (19.4 wt%), which was produced by gas atomization and additive manufacturing through laser metal deposition. The forward and reverse gamma - epsilon MT is studied by mechanical spectroscopy through the internal friction spectra and the dynamic modulus variation, together with a parallel microstructural characterization including in-situ observation of the gamma - epsilon MT during cooling and heating at the scanning electron microscope. The evolution of the transformed fraction of epsilon martensite, evaluated through the integral area of the internal friction peak, was followed along thermal cycling in all three alloys. Both, the internal friction and the electron microscopy studies show that the epsilon martensite amount increases very fast during the first few cycles, and then decreases with a tendency towards its stabilization for many tens of cycles. The results show that the gamma - epsilon MT is more stable on cycling in the additive manufactured sample than in the conventionally processed samples, opening new avenues for designing shape memory steels to be specifically processed through additive manufacturing.This work was supported by the ELKARTEK-CEMAP (KK-2020/00047) project from the Industry Department of the Basque Government, and the GIU-17/071 from the University of the Basque Country, UPV/EHU. This work made use of the SGIKER facilities at the UPV/EHU

    Designing for shape memory in additive manufacturing of Cu-Al-Ni shape memory alloy processed by laser powder bed fusion

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    Shape memory alloys (SMAs) are functional materials that are being applied in practically all industries, from aerospace to biomedical sectors, and at present the scientific and technologic communities are looking to gain the advantages offered by the new processing technologies of additive manufacturing (AM). However, the use of AM to produce functional materials, like SMAs, constitutes a real challenge due to the particularly well controlled microstructure required to exhibit the functional property of shape memory. In the present work, the design of the complete AM processing route, from powder atomization to laser powder bed fusion for AM and hot isostatic pressing (HIP), is approached for Cu-Al-Ni SMAs. The microstructure of the different processing states is characterized in relationship with the processing parameters. The thermal martensitic transformation, responsible for the functional properties, is analyzed in a comparative way for each one of the different processed samples. The present results demonstrate that a final post-processing thermal treatment to control the microstructure is crucial to obtain the expected functional properties. Finally, it is demonstrated that using the designed processing route of laser powder bed fusion followed by a post-processing HIP and a final specific thermal treatment, a satisfactory shape memory behavior can be obtained in Cu-Al-Ni SMAs, paving the road for further applications

    KLRG1 expression on natural killer cells is associated with HIV persistence, and its targeting promotes the reduction of the viral reservoir

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    HIV infection; HIV reservoir; ImmunotherapyInfección por VIH; Reservorio de VIH; InmunoterapiaInfecció per VIH; Reservori de VIH; ImmunoteràpiaHuman immunodeficiency virus (HIV) infection induces immunological dysfunction, which limits the elimination of HIV-infected cells during treated infection. Identifying and targeting dysfunctional immune cells might help accelerate the purging of the persistent viral reservoir. Here, we show that chronic HIV infection increases natural killer (NK) cell populations expressing the negative immune regulator KLRG1, both in peripheral blood and lymph nodes. Antiretroviral treatment (ART) does not reestablish these functionally impaired NK populations, and the expression of KLRG1 correlates with active HIV transcription. Targeting KLRG1 with specific antibodies significantly restores the capacity of NK cells to kill HIV-infected cells, reactivates latent HIV present in CD4+ T cells co-expressing KLRG1, and reduces the intact HIV genomes in samples from ART-treated individuals. Our data support the potential use of immunotherapy against the KLRG1 receptor to impact the viral reservoir during HIV persistence.The project leading to these results has received funding from “la Caixa” Banking Foundation under the project code LCF/PR/HR20-00218. This study was also supported by the Agencia Estatal de Investigación project PID2021-123321OB-I00 funded by MCIN/AEI/10.13039/501100011033/FEDER, UE; The Spanish “Ministerio de Economia y Competitividad, Instituto de Salud Carlos III” (ISCIII, PI20/00160); and the Gilead fellowships GLD19/00084, GLD18/00008, GLD21-00049, and GLD22/00152. Part of the methodology was developed with the support of the grant 202104-30-31 from Fundació la Marató de TV3. M.B. is supported by the Miguel Servet program funded by the Spanish Health Institute Carlos III (CPII22/00005). A.A.-G. was supported by the Spanish Secretariat of Science and Innovation Ph.D. fellowship (BES-2016-076382). D.P. was supported by the VHIR Ph.D programme 2020. Spanish Secretariat of Science and Innovation Ph.D. fellowship. E.M.G. was supported by the Ramón y Cajal Program (RYC2018-024374-I) funded by the Spanish Secretariat of Science and Innovation, by the Comunidad de Madrid Talento Program (2017-T1/BMD-5396), and by the project PID2021-127899OB-I00 funded by MCIN /AEI /10.13039/501100011033/ FEDER, UE. We thank Dr. Joan Puñet from the flow cytometry core at the Vall d’Hebron Research Institute for his technical and scientific expertise. The funders had no role in study design, data collection, and analysis, the decision to publish, or preparation of the manuscript
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