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Analysing the Level of Decentralisation of Spanish Firms: Assessment and Associated Factors
No full textDecentralization has proven to be an important factor of competitiveness for companies, especially in the face of turbulent and uncertain economic scenarios. This research, applying the World Management Survey methodology, analyzes the level of decentralization of Spanish companies, exploring the factors associated with it. A very low level of average decentralization has been found, and that larger companies, with an international presence and with greater skills of their employees tend to present more decentralized structures
Study of an alternative route for alumina production: Integration of calcium looping to Pedersen process aiming at zero emissions and bauxite residue avoidance
No full textThe aluminium industry is a notable emitter of CO2 and a significant contributor to mineral scarcity. Alumina extraction, typically conducted via the Bayer process, faces two main challenges: using fossil fuels and generating bauxite residue. A recently proposed approach, the Pedersen process, aims to address these challenges by removing the iron oxide content from the ore through an additional iron smelting step, thereby eliminating the generation of bauxite residue. This study evaluates the material and energy performance of alumina and pig iron co-production from bauxite using the principles of the Pedersen process. Different thermodynamic simulations of a Pedersen process layout were carried out using Aspen Plus software, and key parameters were validated against existing literature. Additionally, diverse CO2 capture configurations based on calcium looping were assessed, performing an energy optimization to achieve carbon-neutral and zero-residue alumina production.
Results indicate that the energy demand of the Pedersen process is notably higher than the average Bayer process for bauxites with high aluminium/iron ratios, with an estimated energy consumption of 11.92 GJ per tonne of products. However, low aluminium/iron ratios render better energy performances (10.15 GJ per tonne), showing potential feasibility in terms of energy consumption. The integration of a calcium-looping plant led to low energy penalties, thanks to the replacement of CaCO3 in the Pedersen plant by adding purged CaO from the calcium-looping plant. The energy penalties, estimated at a minimum of 1.10-2.79 GJ per tonne of CO2 avoided, show favourable results that could pave the way for a smarter use of resources and a decarbonized alumina production
Learning migration and diversity through artistic narration: an application of diasporic education to the Spanish context
No full textThis article examines how artistic and narrative expression can enhance intercultural education in Spanish primary schools located in low-population-density areas with increasing cultural diversity. Grounded in the concept of diasporic education, the study focuses on the lived experiences of children—both migrant and non-migrant—who narrate and illustrate their perceptions of migration through written stories and drawings. The research adopts a qualitative ethnographic design with a participatory approach, involving 50 primary school students aged 11–12 from two schools in Aragón, Spain. By analysing these materials, the research explores how transmedia storytelling can serve as a pedagogical tool to promote empathy, inclusion, and critical reflection in the classroom. The study contributes locally by addressing the challenges of educational integration in rural Spain and globally by connecting with broader discussions on minority representation, educational equity, and creative pedagogies. Findings highlight the transformative potential of incorporating students’ voices and artistic productions into teaching practices, fostering more inclusive and culturally responsive learning environments
Fortuna y Maniac: dos rutas literarias hacia el capitalismo posmoderno y la deshumanización progresiva
No full textHace un tiempo tuve la oportunidad de leer dos libros: Fortuna, de Hernán Díaz (Premio Pulitzer, 2023) y Maniac, (2023), de Benjamín Labatut: dos novelas publicadas el mismo año por la editorial Anagrama. Dos novelas aparentemente diferentes, dos novelas aparentemente con temas específicos. Debo decir que había pasado un tiempo desde su lectura, hasta que una noche, en la universidad, me puse a escribir un ensayo sobre las narrativas legitimadoras del capitalismo posmoderno como sistema socio simbólico y económico: ambas novelas me vinieron a la cabeza. Entonces comprendí que debía dejar a un lado la compleja sociología fenomenológica. ¿Por qué? Pues porque en las novelas estaba la respuesta a mi tesis y de una forma mucho más clara y precisa..
Immunogenicity, security and protection against small ruminant lentivirus (SRLV) challenge in sheep, induced by intranasal immunization with a recombinant Sendai virus vector expressing SRLV gag-P25
No full textSmall ruminant lentiviruses (SRLV) are responsible for significant economic losses in sheep and goat farming; however, effective vaccination strategies remain unavailable. This study evaluated the immunogenicity, safety, and protective efficacy of a recombinant Sendai virus vector (SeV) expressing SRLV gag-P25 (rSeV-GFP-P25) in lambs. Twenty-one SRLV-negative lambs were divided into three groups and inoculated intranasally thrice with culture medium (group 1); SeV-GFP (group 2) or rSeV-GFP-P25 (group 3). Lambs were challenged with homologous SRLV at 16 weeks post-first immunization. Clinical and hematological parameters, antibody responses, SRLV viral loads in peripheral blood mononuclear cells (PBMCs) and target tissues, histopathological and histomorphometric analyses, assisted with artificial intelligence, of interstitial pneumonia were assessed. No clinicopathological alterations were observed, except for a transient temperature increase in group 3 post-first immunization. Group 2 showed mild SeV-neutralizing antibodies, while rSeV-GFP-P25 (group 3) induced negligible SRLV-specific antibody responses. Group 3 exhibited higher SRLV DNA copies in PBMCs but lower in most SRLV target tissues compared to control groups, with no SRLV DNA detected in spleen and bone marrow. Histomorphometry revealed reduced alveolar septal thickening in group 3, indicating partial protection against early SRLV-associated interstitial pneumonia. These results warrant further investigation into cellular immunity and long-term protection
3D-printed Ni/γ-Al2O3 catalysts for CO2 methanation: Effect of Ni loading and sintering temperature
No full textAdditive manufacturing (AM) technologies are revolutionizing the production of ceramic components, particularly in fields like catalysis, where complex shapes offer remarkable advantages in performance. AM also minimizes material waste while reducing the number of fabrication steps. This work is focused on the fabrication of Ni/γ-Al2O3 monoliths for CO2 methanation in one step by using Direct-Ink Writing (DIW) of Ni-enriched hydrogel-based γ-Al2O3 inks, and the debinding and sintering in a single thermal treatment. For this purpose, the influence of Ni precursor amount (2.5–5.0 wt% Ni) on the rheological properties of inks and the catalytic activity is investigated. Monoliths with woodpile architecture and 50 % infill are sintered at 450 °C and 600 °C to determine the effect of the sintering temperature on the Ni distribution in the catalyst. Results evidence successful incorporation of the metallic active phase into the monolithic structures. Both the Ni amount and sintering temperature are key factors to enhance the CO2 methanation performance. The 5.0 wt% Ni monolith sintered at 450 °C presents both the highest CO2 conversion and methane selectivity at 350–500 °C, due to better reduction degree, dispersion, and smaller size of Ni nanoparticles at the maximum metal loading. These remarkable results demonstrate the potential of DIW for the fabrication of fully 3D-printed monolithic catalysts with well-dispersed metal particles, all while minimizing production steps
Five-repetition chair-stand test vs. handgrip strength: Which better predicts mortality risk? a follow-up study in 43,605 middle-aged and older adults
No full textBackground: Ageing reduces muscle strength and function, increasing mortality risk. Identifying simple performance markers can guide interventions for healthy ageing.
Objective: To assess the prospective dose-response association of the 5-repetition Chair Stand Test (5-CST) and handgrip strength (HGS) with mortality in middle-aged and older adults. Methods: This prospective study included community-dwelling participants aged 50 years or older from the SHARE study. HGS and 5-CST were assessed at baseline, with all-cause mortality tracked through follow-up interviews. Cox regression with restricted cubic splines was used, controlling for several confounders.
Results: 43,605 participants (mean age (SD): 65.3 (9.1), 54 % women) were included. During a mean follow-up of 7.3 ± 2.2 years, there were 4154 deaths (9.5 %). Both 5-CST and HGS were curvilinearly associated with all- cause mortality. Using the median level of 5-CST as a reference (11 s), 10th percentile of 5-CST (7 s) showed a hazard ratio (HR) of 0.74 (95 %CI: 0.69, 0.80). The 90th percentile (18 s) of 5-CST showed a HR of 1.18 (95 % CI: 1.14, 1.22). Stratified analysis indicated 5-CST was most strongly associated with mortality in women. Regarding HGS, using the median level as a reference (33 kg), the 10th percentile of muscle strength (21 kg) showed a HR of 1.62 (95 %CI: 1.50, 1.75). The 90th percentile (51 kg) of muscle strength showed a HR of 0.58 (95 %CI: 0.52, 0.64).
Conclusion: Both tools provide valuable information, but HGS may be considered more relevant for identifying those at increased mortality risk, while 5-CST may be especially useful in women
Graphene Quantum Dots Drive Spontaneous Metal Reduction to form Stable and Electroactive Core‐Shell Nanocolloids
No full textThis work demonstrates a spontaneous synthesis of ∼8.0, ∼7.0, and ∼3.0 nm diameter Au, Ag, and Pt cores; respectively, wrapped by as‐synthesized crystalline graphene‐quantum dots (GQDs). Functional sp2‐ and sp3‐hybridized carbons play a crucial role upon the synthesis, electronic distribution at the interface, and conductive sites for improving the electrocatalytic response. Au nanohybrids (NHs) demonstrated two‐fold increase in current density with respect to conventional citrate‐coated Au nanoparticles. This was attributed to conductive sp2‐ hybridized carbons and the gain of charge density at the surface of Au as demonstrated by DFT calculations. Due to the sp3‐carbons at the shell, these NHs also behave like simple chemical compounds because they can be precipitated, stored for long periods of time, and redispersed without apparent changes in their properties. The resultant nanocolloids exhibit exceptional stability under harsh conditions. These attributes make them useful NHs with great potential for broad applications
Ethics of Empathy and Personal Shift in Lucy Caldwell’s These Days
No full textThe article discusses the ethics of empathy and personal transformation in Lucy Caldwell’s These Days (2022). In this award-winning historical prose, Caldwell creates an alternative literary space to commemorate the victims of the 1941 Belfast Blitz. I aim to discuss her ethical perspective, which manifests in two key dimensions in the novel: first, by fostering empathetic connections with readers, and second, by illustrating the empathic interactions and transformative journeys of the novel’s female characters. Furthermore, I draw on scholarly definitions of ethics and empathy to demonstrate how a strong emphasis on empathy characterizes Caldwell’s ethical perspective. As These Days stages a fictional revisit to the tragedy and its impact on Caldwell’s native city (Belfast), she vividly portrays human vulnerability and resilience through the female characters, who experience profound personal shifts through empathic encounters. This article demonstrates how These Days calls for human interdependence and, more crucially, considers the interconnectedness of all living beings as a profound source of solace in times of vulnerability and loss
Herland’s Speculative Fiction Offspring: New Materialist Posthuman Ethics in Larissa Lai’s Salt Fish Girl and The Tiger Flu
No full textThis essay explores Larissa Lai’s dystopian speculative fiction through the lenses of Karen Barad’s theory of intra-action, Stacy Alaimo’s notion of transcorporeal material ethics, Jane Bennett’s vital materialism, and Rosi Braidotti’s postanthropocentric, Spinozist revision of Giorgio Agamben’s notion of bare life or zoe. Lai’s feminist posthuman communities, intrinsically embodied and embedded in nature, hold a position of resistance within the overall context of the anthropogenic destruction of the environment. Zoe-centered egalitarianism materializes in their interspecies enmeshment and horizontal relations with the more-than-human as unexpected material intra-actions enable their posthuman being and becoming. Furthermore, those communities lie beyond the grasp of the reproductive futurism that has been adduced as a feature of Charlotte Perkins Gilman’s controversial utopia Herland