University of Extremadura
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Three-Dimensional bioprinting of GelMA hydrogels with culture medium: balancing printability, rheology and cell viability for tissue regeneration
No full textThree-dimensional extrusion bioprinting technology aims to become a fundamental tool for tissue regeneration using cell-loaded hydrogels. These biomaterials must have highly specific mechanical and biological properties that allow them to generate biosimilar structures by successive layering of material while maintaining cell viability. The rheological properties of hydrogels used as bioinks are critical to their printability. Correct printability of hydrogels allows the replication of biomimetic structures, which are of great use in medicine, tissue engineering and other fields of study that require the three-dimensional replication of different tissues. When bioprinting cell-loaded hydrogels, a small amount of culture medium can be added to ensure adequate survival, which can modify the rheological properties of the hydrogels. GelMA is a hydrogel used in bioprinting, with very interesting properties and rheological parameters that have been studied and defined for its basic formulation. However, the changes that occur in its rheological parameters and therefore in its printability, when it is mixed with the culture medium necessary to house the cells inside, are unknown. Therefore, in this work, a comparative study of GelMA 100% and GelMA in the proportions 3:1 (GelMA 75%) and 1:1 (GelMA 50%) with culture medium was carried out to determine the printability of the gel (using a device of our own invention), its main rheological parameters and its toxicity after the addition of the medium and to observe whether significant differences in cell viability occur. This raises the possibility of its use in regenerative medicine using a 3D extrusion bioprinter.This research was funded by the European Regional Development Fund (ERDF), in the framework of the project (BIOSIMPRO. IB20158) with the code 2021/00110/001 and was funded by project BIOIMP_ACE_MAS_6_E, co-funded by the European Union through the Interreg VI-A Spain-Portugal Programme (POCTEP) 2021-2027.peerReviewe
A la señorita Antonia Mateos Sánchez en el día de su cumpleaños
No full textReproducción facsímil del poema A la señorita Antonia Mateos Sánchez en el día de su cumpleaños. Poema escrito por Heliodoro Vega Barbero (padre del médico y escritor Celestino Vega Mateos) en Serradilla (Cáceres) el 17 de octubre de 1898.Facsimile reproduction of the poem A la señorita Antonia Mateos Sánchez en el día de su cumpleaños. Poem written by Heliodoro Vega Barbero (father of the doctor and writer Celestino Vega Mateos) in Serradilla (Cáceres) October 17, 1898.peerReviewe
The impact of photovoltaic self-consumption on the daily electricity demand in Spain: Definition of a model to estimate it
No full textIntroduction: A radical shift in energy production is underway worldwide, replacing fossil fuels
with renewable sources and causing structural changes in power generation systems.
Problem statement: Photovoltaic installations for self-consumption have experienced a steep increase
in recent years. They have reached a significant installed capacity to cause a noticeable
reduction in consumption from the national grid, which can cause serious management problems.
Objectives: In this work, the evolution of the Spanish demand in the last years is analyzed to
identify the influence of self-consumption in the overall demand. In addition, a mathematical
model is defined to estimate this influence.
Methodology: The demand curves of equivalent days in years with high and low installed selfconsumption
photovoltaic systems have been compared. Then, an estimation of the electricity
generated with this source is proposed, with a mathematical model that takes into account data
on solar radiation, installed photovoltaic power for self-consumption and other relevant factors.
Results: The analysis of the demand has shown a significant reduction of the electricity demand in
daylight hours when the number of self-consumption photovoltaic systems increases. Moreover,
the proposed model has been able to provide an estimation of the electricity generated with this
source. The addition of these estimates to the actual consumption curves of years with a high
number of self-consumption installations gives profiles close to those obtained when selfconsumption
was low.
Recommendation: New storage systems need to be implemented and grid management need to be
improved to take advantage of the surpluses produced by photovoltaic systems.This work was supported by the project TED2021-131671B–I00 funded by MCIN/AEI/10.13039/501100011033 and by the European Union NextGenerationEU/PRTR.peerReviewe
The unknown faces of Santa María de Guareña
No full textEn las excavaciones arqueológicas de Casas del Turuñuelo situadas en el término municipal de Guareña han aparecido recientemente diferentes relieves de caras inéditas y desconocidas, es por ello, que nos atrevemos a describir y plasmar con fotografías otras caras desconocidas mas cercanas a nosotros y también inéditas en la arquitectura religiosa. Son las caras presentes en las fachadas del exterior de la enorme Iglesia de Santa María de la localidad de Guareña.
Por debajo de cada gárgola aparecen rostros o caras desapercibidas, se encuentran a gran altura lo que hace que sea difícil su observación, por ello, no son contempladas por la gran mayoría feligreses y visitantes de la iglesia. Las expresiones de las caras son diversas y diferentes, no se sabe a ciencia cierta la intención exacta del autor de la obra. La gran mayoría se pueden observar en la parte inferior de las gárgolas. Asimismo, hay otras caras debajo de las ventanas de la fachada sur que serán expuestas para su difusión. En este trabajo solamente se van a tratar las caras del exterior del templo.In the archaeological excavations of Casas del Turuñuelo located in the municipality of Guareña, different reliefs of unpublished and unknown faces have recently appeared, which is why we dare to describe and capture with photographs other unknown faces closer to us and also unpublished in religious architecture. They are the faces present on the exterior facades of the enormous Church of Santa María in the town of Guareña.
Below each gargoyle, faces or unnoticed faces appear. They are at a high altitude which makes them difficult to observe, therefore, they are not observed by the vast majority of parishioners and visitors to the church. The expressions on the faces are diverse and different, the exact intention of the author of the work is not known for certain. The vast majority can be seen at the bottom of the gargoyles, there are also other faces under the windows of the south façade that will be exposed for disclosure.In this work, only the exterior faces of the temple will be treated.peerReviewe
History of poetry in Mexican textbooks
No full textEste artículo tiene como objetivo analizar la evolución del uso de la poesía en los libros de texto mexicanos de nivel primaria. El corpus analizado está constituido por los libros con las transformaciones más significativas, los de 1962, 1972 y 2008, para un total de 35 libros. Los principales resultados indican que el papel de la poesía en los libros de texto ha cambiado considerablemente en respuesta a diferentes concepciones educativas, culturales y políticas. Los libros de 1962 presentan escritores consagrados del Romanticismo y el Modernismo y tienen un gran interés por fomentar los valores patrióticos y morales. Los de 1972 se inclinan hacia la lírica folklórica mexicana y tienen un tono más lúdico, marcado por rondas, cantos y poemas para jugar. Los de 2008 dan prioridad al desarrollo de la lectura funcional, por lo que los modelos literarios pierden importancia y especialmente la poesía, que casi desaparece. Este análisis demuestra las diferencias en cómo se han construido estas antologías, cómo se relacionan con su contexto histórico y da algunas pautas sobre cómo se puede mejorar la didáctica de la poesía en los libros de texto del futuro.This article aims to analyze the evolution of the use of poetry in Mexican primary level textbooks. The analyzed corpus consisted of the books with the most significant changes, those from 1962, 1972, and 2008, for a total of 35 books. The main results indicate that the role of poetry in textbooks has changed considerably in response to different educational, cultural, and political conceptions. The 1962 books mainly feature acclaimed Romantic and Modernist writers and have a strong interest in promoting patriotic and moral values. The 1972 books lean towards Mexican folk lyricism and have a more playful tone, marked by songs, and poems for playing. Finally, the 2008 books prioritize functional reading development, leading to a notable reduction in the importance of literary models, especially poetry. This analysis demonstrates the differences in how these anthologies were constructed, how they relate to their historical context, and provides some guidelines on how to improve the didactics of poetry in textbooks in the future.peerReviewe
Optimal location of electric vehicle charging stations using proximity diagrams
No full textThe concern over the planet environmental crisis is propelling administrations to promote antipollution regulations progressively restricting the use of fossil fuels. In this context, the integration of electric vehicles is ncreasingly being explored to reduce traffic emissions. To facilitate the transition from conventional vehicles to electrical ones, establishment of a robust charging infrastructure is essential. This article presents a numerical proposal for identifying potential optimal locations of additional electrical charging stations building upon the current infrastructure. For this purpose, Voronoi diagrams, constructed using the existing charging stations as point generators of the structure, will be stated as the primary framework. The extracted proximity data, delimited by geographical, legislative or user behavior-related factors, facilitates the identification of locations where companies in the sector are inclined to invest. This procedure holds significant relevance for industry in the sector seeking strategic investment locations that minimize competition while ensuring a high level of convenience for long-distance electrical vehicles users. The significance of this modeling lies in its simplicity and applicability to any region worldwide, making it a versatile tool for similar studies
Reply to Gijon-Nogueron, G. Comment on “Alfageme-Garcia et al. Respectful Children’s Shoes: A Systematic Review. Children 2024, 11, 761”
No full textThis is a systematic review, which has taken us a long time to work on and we did not have much bibliography for it.
The systematic review followed a clearly defined and structured methodology. This included the formulation of specific research questions, the definition of the inclusion and exclusion criteria, and the application of a pre-established protocol for the search and selection of studies The conclusions were derived from cohesive evidence, where multiple studies point in the same direction, reinforcing the validity of the findings. With the limitations that we have found when working on this topic., it makes us aware of the importance of continuing research in this line. En primer lugar, se trata de una revisión sistemática, que nos ha llevado mucho tiempo de trabajo y para la que no disponíamos de mucha bibliografía.peerReviewe
Bebidas energéticas y sus efectos
No full textINTRODUCCIÓN. En los últimos años las bebidas energéticas han aumentado su popularidad, especialmente entre la población joven. Están compuestas principalmente por cafeína, taurina, azúcares y otros ingredientes como el guaraná, vitaminas del grupo B, ginkgo o glucuronolactona. La mezcla de estas bebidas con el alcohol también ha creado preocupaciones.
OBJETIVO. El objetivo es conocer el impacto de las bebidas energéticas en la salud de adolescentes y adultos jóvenes.
METODOLOGÍA. Se trata de una revisión bibliográfica en Pub Med, Google Schoolar, IBECS, Scopus, Cuiden, Cochrane y Scielo acotada a los últimos cinco años. En total se utilizaron 27 artículos.
RESULTADOS. Aunque los efectos de la cafeína han sido muy estudiados, otros compuestos poseen una literatura más limitada. La evidencia presentada sugiere que los efectos adversos de las bebidas energéticas más frecuentes son taquicardia, palpitaciones, nerviosismo, insomnio y malestar gastrointestinal, aunque un abuso de ellas podría tener consecuencias más graves. Respecto a la mezcla con alcohol se expone que pueden enmascarar los efectos de la sedación, pero no reducen la intoxicación.
CONCLUSIONES. Se necesitan más estudios que contribuyan a una mayor evidencia científica sobre las bebidas energéticas.INTRODUCTION. In recent years, energy drinks have increased in popularity, especially among the young population. They are mainly composed of caffeine, taurine, sugars and other ingredients such as guarana, group B vitamins, ginko or glucoronolactone. Mixing these drinks with alcohol has also created concerns.
OBJECTIVE. The objective is to know the impact of energy drinks on the health of adolescents and young adults.
METHODOLOGY. This is a bibliographic review in Pub Med, Google Schoolar, IBECS, Scopus, Cuiden, Cochrane and Scielo limited to the last five years. In total 27 articles were used.
RESULTS. Although the effects of caffeine have been well studied, other compounds have more limited literature. The evidence presented suggests that the most common adverse effects of energy drinks are tachycardia, palpitations, nervousness, insomnia, and gastrointestinal discomfort, although abuse of them could have more serious consequences. Regarding the mixture with alcohol, it can mask the effects of sedation, but they do not reduce intoxication.
CONCLUSIONS. More studies are needed that contribute to greater scientific evidence on energy drinks.Memoria del proyecto, 38 p.Grado en Enfermería. Universidad de Extremadur
Change in Land Use Affects Soil Organic Carbon Dynamics and Distribution in Tropical Systems
No full textAnthropogenic land cover change is directly responsible for the deforestation and degra-dation of tropical forests. In this context, assessing soil organic carbon (SOC) stocks is key to understanding the impact of anthropogenic activities on SOC so that we can implement management practices that effectively reduce emissions or promote carbon sequestration. Our objective was to assess the effect of land-use change on the dynamics and distribution of SOC in three systems (agriculture, pasture and agroforestry) after 40 years of deforestation in a tropical dry forest in the central–eastern region of Honduras. For this purpose, the bulk density, percentage of coarse fragments (>2 mm) and soil organic carbon content were determined at three depths (0.00–0.10 m, 0.10–0.20 m and 0.20–0.30 m). The results showed an increase in bulk density for all new uses, although soil compaction had not yet occurred. In terms of total soil organic carbon (TOC) stocks, deforestation caused a decrease from 17% to 48% in agricultural and agroforestry soils, respectively; on the other hand, grasslands did not show significant differences compared to tropical dry forest, suggesting that they have a high potential as carbon sinks in deforested tropical areas. However, this did not imply a better state of the system, as the greatest increases in bulk density were found in pastures.peerReviewe
Ética del cuidado en escritoras chicanas lesbianas
No full textEl volumen de Carla Trujillo (1991) Chicana Lesbians: The Girls our Mothers Warned Us About retaba en el momento de su publicación posicionamientos e ideologías sobre roles de género y sexo. El controvertido tema de la ética del cuidado, debatido y entendido en las teorías ecofeministas como el imperativo impuesto por sociedades patriarcales
para convertir a las mujeres en cuidadoras, encuentra en estos textos reflexiones desde las identidades queer de sus autoras, quienes transforman sus acciones en interacciones positivas. En la compilación mencionada abundan las relaciones de sororidad, en las que expresan el amor y el cuidado mutuo, a la vez que se exploran nuevas alternativas de construcción de familia, fuera de modelos heteropatriarcales. Entre estas exploraciones, los poemas y ensayos incluidos en el volumen se comunicaban entonces a través del erotismo y la sexualidad, debatiendo abiertamente sus implicaciones, intentando superar la problemática de una sexualidad e, incluso, una maternidad impuesta. Gracias al
trabajo previo de escritoras y críticas como Gloria Anzaldúa, Ana Castillo, Cherrie Moraga, Emma Pérez o la propia Carla Trujillo, cuyas historias aparecen en esta compilación, las escritoras chicanas lesbianas actuales evitan caer en visiones esencialistas que colocan a las mujeres y sujetos queer cerca de la naturaleza para devaluarlas y encontrar la justificación de su opresión. Al contrario, el volumen de Trujillo abre nuevos caminos hacia una tendencia más posantropocéntrica, más empática hacia el mundo humano y más que humano, para hacer a estas escritoras más conscientes de la influencia de sus orígenes, abrazando sus raíces con expresión de amor y cuidado hacia otras mujeres.Chicana Lesbians: The Girls our Mothers Warned Us About (1991) by Carla Trujillo challenged conventional positions and ideology about gender and sexual roles when it was published. The controversial issue of the ethics of care, discussed and understood in ecofeminist theories as the imperative of heteropatriarchal societies towards women to
become caretakers, finds in these texts reflections from the queer identities of their authors, transforming their actions into positive interactions. In this volume, relationships of sorority, expressing love and care for one another abound as the writers in the compilation explore new alternatives of building families aside from heteropatriarchal role models. Among these explorations, the different poems and essays
included in the volume established a communication through eroticism and sexuality,
and discussed their implications openly, in order to overcome the problematics of an
imposed heterosexuality and, even, an imposed motherhood. This collection expresses
how, thanks to all this previous work by writers and critics such as Gloria Anzaldúa, Ana
Castillo, Cherrie Moraga, Emma Pérez or Carla Trujillo herself, whose stories are
included in the volume, Chicana lesbian writers today can escape essentialist visions that
place women and queers as closer to nature in order to undervalue both and find the
justification to oppress them. On the contrary, Trujillo’s volume opens an avenue towards
a more post anthropocentric attitude, exercising empathy towards the human and the
more-than-human world in relation to making these writers aware of the influence of
their origins, and the embracement of their roots through the expression of love and
caring for other womenpeerReviewe