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Item Conocimiento libre en tiempos de pandemia. Estudio de los artículos “Covid-19” y “Pandemia por Covid-19” en Wikipedia(Interface – Comunicação, Saúde, Educação, 2021) Claes, Florencia; Deltell Escolar, LuisEsta investigación estudia los artículos de “Covid-19” y de “Pandemia por Covid-19” en cuatro versiones lingüísticas de Wikipedia (inglés, español, italiano y portugués). El período de estudio comienza con la denominación oficial de la enfermedad como Covid-19, el 11 de febrero de 2020, por la Organización Mundial de la Salud y desde la proclamación por dicha institución de la pandemia causada por esta enfermedad, el 11 de marzo de 2020. En ambos casos se estudia hasta el 11 de abril de 2020. La investigación aborda el modo de creación y de lectura de dichos artículos, analizando si se trata de trabajos construidos desde referencias científicas y sanitarias o prensa generalista. Este proyecto muestra cómo los wikipedistas han reaccionado rápidamente y han generado un gran trabajo colaborativo, con artículos argumentados y construidos desde una perspectiva científica y sanitaria.Item Voltage-controlled rotation of magnetic anisotropy in the Ni 90Fe 10/BaTiO 3(001) heterostructure(Materials Advances, 2025) Begué Gracia, Adrián; Khaliq, M. W.; Cotón, Noelia; Lorenzo Feijoó, Iker; Niño, Miguel Ángel; Foerster, Michael; Ranchal Sánchez, RocíoIn this work, we demonstrate the voltage control of magnetic anisotropy in a strain-mediated Ni 90 Fe 10 /BaTiO 3 (001) heterostructure. In the pristine state of the heterostructure, the magneto-optical Kerr effect measurements show a transcritical hysteresis loop for the Ni 90 Fe 10 film, indicating a weak perpendicular anisotropy. This was further confirmed by X-ray magnetic circular dichroism – photo-emission electron microscopy, revealing stripe domains in this film. X-ray diffraction analysis of the BaTiO 3 substrate under varying electric fields was used to analyze the orientation of ferroelectric domains. These results indicated that BaTiO 3 exhibits two distinct states depending on the applied electric field: one with domains aligned with the electric field and another with random domain orientation when the field is removed. After substrate poling, the Ni 90 Fe 10 layer switches from weak perpendicular anisotropy to an in-plane uniaxial magnetic anisotropy, with the in-plane direction of anisotropy being controllable by 901 through an electric field. This effect is due to an efficient strain transfer from BaTiO 3 to the Ni 90 Fe 10 lattice, induced by ferroelectric polarization, as shown by XRD. Remarkably, this rotation of the magnetic anisotropy leads to an enhanced converse magnetoelectric coupling value of 1.43 ms m 1 , surpassing previously reported values for other BaTiO 3 -based heterostructures by an order of magnitude. These results emphasize the potential of Ni 90 Fe 10 alloys for next-generation magnetoelectric devices.Item Complex Body Wall Closure Defects in Seven Dog Fetuses: An Anatomic and CT Scan Study.(Animals, 2025) Martín Alguacil, María Nieves; Cozar, José M; Avedillo Cea, Luis JavierBody stalk anomaly (BSA) is a rare and usually fatal congenital disorder involving severe malformations of the body wall, limbs, spine, and internal organs. This study presents the first documented cases of BSA in seven dogs, offering new insights into how the disorder manifests in animals. The affected fetuses consistently exhibited major anomalies, including large abdominal wall defects, structural spinal abnormalities, and a variety of limb malformations ranging from partial agenesis and meromelia to phocomelia and complete amelia. Structural urogenital anomalies and orofacial clefts were also observed, aligning with similar findings in BSA cases reported in pigs and cats. These findings support the hypothesis of a multifactorial etiology involving early embryonic disruptions, such as abnormal folding of the embryo, rupture of the amniotic membrane, and vascular compromise. The frequent occurrence of abdominal wall defects alongside umbilical cord abnormalities further suggests a shared developmental pathway. This study also highlights the value of veterinary cases in comparative embryology and the need to assess congenital anomalies as part of a broader malformation complex. By expanding the phenotypic spectrum of BSA in domestic animals, this work contributes to a deeper understanding of its pathogenesis and emphasizes the importance of further research into the genetic and environmental factors involved. Such efforts could lead to improved classification and diagnosis of complex congenital malformations, as well as facilitate cross-species comparisons.Item Social movements and the left in Portugal and Spain (2008-2015): by Tiago Carvalho, Amsterdam, Amsterdam University Press, 2022, 230 pp., €117. 00 (hardback) ISBN 9789463722841(Contesting austerity: social movements and the left in Portugal and Spain (2008-2015), 2025) Díez García, RubénItem Bioaccumulation of trace elements in white storks (Ciconia ciconia): Effects of age, health, and anthropogenic exposure.(Environmental Pollution, 2025) Fernández Valeriano, Rocío; Pastor Tiburón, Natalia; González González, Fernando; Ruiz Suárez, Norberto; Zumbado, Manuel; Martín Cruz, Beatriz; Rodríguez Hernández, Ángel; Acosta Dacal, Andrea; Henríquez Hernández, Luis Alberto; Luzardo, Octavio PWhite storks (Ciconia ciconia) are recognized as effective bioindicators of environmental contamination due to their wide distribution and trophic flexibility. In this study, we analyzed blood concentrations of 47 essential, toxic, and potentially toxic elements in 189 white storks from central Spain, assessing the influence of age, health status, and anthropogenic pressure on metal accumulation. Birds were grouped into chicks, fledglings, and adults. Statistical comparisons were performed using non-parametric tests and general linear models (GLMs), depending on data distribution. Our findings indicate that age significantly affects metal accumulation, with fledglings exhibiting higher concentrations of lead (Pb, p = 0.0024), arsenic (As, p = 0.0012), cadmium (Cd, p = 0.0476), and manganese (Mn, p = 0.0467) compared to adults, suggesting increased exposure through parental feeding and trophic transfer. Health status was also a critical determinant: sick individuals showed significantly elevated levels of Cd (p < 0.0001), Pb (p < 0.0001), and As (p = 0.0166), supporting the role of metal toxicity in avian morbidity. In terms of anthropogenic exposure, storks sampled within 30 km of landfills exhibited significantly higher concentrations of As (p = 0.0002), Cd (p = 0.0118), and Hg (p = 0.0412). Individuals with foreign materials in the digestive tract also showed increased Pb (p = 0.0007) and Cd (p = 0.0008) levels. Conversely, no significant differences were found between individuals from areas of high versus low human population density. These results highlight the impact of environmental pollution on metal bioaccumulation in white storks and demonstrate the influence of landfill proximity and trophic exposure on contaminant burdens. Given their role as a sentinel species, our findings underscore the need for stricter waste management policies and continued biomonitoring efforts to mitigate toxic metal exposure in wildlife.Item Evaluating the stability of antibody titres against Leishmania infantum determined by IFAT in long-term stored canine frozen samples.(Parasites and Vectors, 2025) Olmeda, Patricia; Díaz-Regañón Fernández, David Rafael; Villaescusa Fernández, Alejandra; Amusategui, Inmaculada; Tesouro Díez, Miguel Ángel; Rodríguez Franco, Fernando; García-Sancho Téllez, Mercedes Guadalupe; Martín Fraile, Daniel; Sainz Rodríguez, ÁngelAbstract Background The immunofluorescence antibody test (IFAT) is a serological diagnostic technique used to quantify serum antibodies generated in response to exposure to various pathogens, such as Leishmania infantum. Retrospec tive analysis of previously collected frozen samples is highly valuable for clinical and research purposes. The primary aim of this study was to evaluate the impact of long-term frozen storage of canine plasma samples on the IFAT-based serological diagnosis of L. infantum exposure. Methods A total of 189 frozen plasma samples from dogs stored at −20 °C for 5, 10 or 20 years, which had previously been tested for L. infantum exposure via IFAT (IgG), were reanalysed to assess the concordance between past and cur rent qualitative and quantitative results. Results The qualitative agreement between the former and current IFATs was 92.1%. The samples from 20 years prior presented the greatest increase in negative samples in the second analysis (from 28.6 to 39.7%). A strong positive cor relation was observed between the quantitative measurements of the past and present across all three groups. The exact quantitative agreement was 48.7%. Conclusions The results of this study indicate that freezing at −20 °C is a good technique for prolonged storage of samples for the detection of L. infantum exposure in dogs, as the qualitative IFAT result is not significantly altered. This finding is of particular interest both for clinical endeavours and for future research in this field.Item Local spectral theory for subordinated operators: The Cesàro operator and beyond(Journal of the London Mathematical Society, 2025) Gallardo Gutiérrez, Eva Antonia; González Doña, F. JavierWe study local spectral properties for subordinated operators arising from C0-semigroups. Specifically, if T = (Tt)t≥0 is a C0-semigroup acting boundedly on a complex Banach space and Hν is the subordinated operator associated to T , where ν is a sufficiently regular complex Borel measure supported on [0,∞), it is shown that Hν does not enjoy the Single Valued Extension Property (SVEP) and has dense glocal spectral subspaces in terms of the spectrum of the generator of T . Likewise, the adjoint H∗ν has trivial spectral subspaces and enjoys the Dunford property. As an application, for the classical Cesàro operator C acting on the Hardy spaces Hp (1 < p < ∞), it follows that the local spectrum of C at any non-zero Hp-function or the spectrum of the restriction of C to any of its nontrivial closed invariant subspaces coincides with the spectrum of C. Finally, we characterize the local spectral properties of subordinated operators arising from hyperbolic semigroups of composition operators acting on Hp (1 < p < ∞), which will depend only on the geometry of the associated Koenigs domain.Item Hernando Morejón, Jacobo y Pilar Garrido Clemente (eds.). "Estudios en neomedievalismo : juegos, letras y viñetas", Granada, Comares, 2023, 160 pp.(Neomedieval, 2024) Gonçalves Soares, Ana RitaItem Interactive Effects of Warming and Competition Do Not Limit the Adaptive Plastic Response to Drought in Populations of a Mediterranean Plant(Global Change Biology, 2025) Ramos Muñoz, Marina; Blanco Sánchez, Mario; Pías Couso, María Beatriz; Ramírez Valiente, José Alberto; Benavides, Raquel; Escudero, Adrián; Matesanz, SilviaWater scarcity is the main selective pressure determining the performance of Mediterranean plant populations, with climate change predicted to increase the intensity and duration of droughts. However, drought rarely acts in isolation. Climate change also involves substantial warming in this region and may disrupt natural processes, including biotic interactions. Phenotypic plasticity allows plants to cope with rapid and multifaceted environmental changes. Although our knowledge of plastic responses to drought in Mediterranean plants has increased in recent years, how co-occurring simultaneous stressors interact to produce additive, synergistic, or antagonistic effects that enhance or constrain adaptive plastic responses to drought is still unknown. Using a factorial experimental approach based on a multivariate common garden, we assessed whether adaptive phenotypic plasticity to drought and population differentiation in traits related to drought response were affected by the occurrence of other key simultaneous stressors, warming and intraspecific competition, in a Mediterranean gypsum endemic shrub. In response to drought, plants expressed adaptive plastic responses associated with a mixed resource-use strategy, combining conservative (sclerophyllous leaves with higher water use efficiency) and acquisitive (advanced phenology) phenotypic responses. Although the response to drought was modified by synergistic and antagonistic interactions with warming and competition, these interactions did not change the direction or reduce the extent of adaptive plasticity to drought. This suggests that plastic responses to drought may also provide benefits against warming and competition. Finally, we detected significant population differentiation in all functional traits, but phenotypic differences in reproductive biomass were significantly reduced under combined drought and warming. Our results emphasize the robustness of adaptive plasticity to drought under complex stress scenarios and underscore the importance of realistic, multifactorial experimental approaches to predict whether adaptive responses of plant populations will remain effective in a climate change context and influence their future ecological and evolutionary dynamics.Item Escasez de profesorado y profesionalización docente: recomendaciones versus prácticas en Europa(Revista Española de Educación Comparada, 2025) Egido Gálvez, María InmaculadaLa escasez de profesorado es un problema mundial que afecta también a Europa y obstaculiza seriamente el adecuado funcionamiento de los sistemas educativos. En este artículo, tras una breve presentación de la dimensión del problema y de las investigaciones relativas a sus causas, se realiza un repaso de las medidas políticas adoptadas para afrontarlo en los países de la Unión Europea, a partir de la revisión de la literatura académica. A continuación, mediante el análisis en profundidad de los dos principales informes publicados recientemente por la Comisión Europea y la Organización para la Cooperación y el Desarrollo Económico (OCDE), se realiza una aproximación a la efectividad previsible de las políticas emprendidas por los países y se contrastan con los discursos de ambas organizaciones sobre la profesionalización docente. Los resultados que arroja el contraste entre las medidas políticas implementadas frente a la escasez y los discursos sobre profesionalización muestran la existencia de aspectos paradójicos que conducen a orientaciones políticas contradictorias para los sistemas educativos. Las conclusiones apuntan a la falta de una posición unívoca de ambos Organismos Internacionales sobre la profesionalización de la docencia y a la pervivencia de concepciones tradicionales sobre la tarea de enseñar. Se enfatiza, además, la importancia de llevar a cabo investigaciones robustas sobre la situación del profesorado centradas en los contextos nacionales y regionales de los países europeos.Item Hydraulic Strategies Modulate Forest Productivity Responses to Hotter Droughts(Global Change Biology, 2025) Tijerín‐Triviño, Julián; Serra‐Maluquer, Xavier; García‐Valdés, Raúl; Zavala, Miguel Ángel; García, Mariano; Astigarraga, Julen; Cruz Alonso, Verónica; Rebollo Orozco, Pedro; Gazol, Antonio; Rodes‐Blanco, Marina; Tanase, Mihai Andrei; Ruiz‐Benito, PalomaClimate change, characterized by an increase in extreme climatic events, poses a significant threat to forest productivity worldwide, potentially compromising its critical role in regulating the global carbon cycle. The response of forest productivity to compound events, such as hotter droughts, can be strongly modulated by functional traits. Forests dominated by acquisitive tree species (prioritizing resource acquisition) may be more vulnerable than forests dominated by conservative species (prioritizing efficiency and stress tolerance). Meanwhile, functional diversity could enhance ecosystem resistance. Although projections indicate that hotter droughts will increasingly hamper forest productivity, most studies focus solely on drought intensity, neglecting duration and frequency. To assess the effects of hotter droughts, we analyzed how their intensity, frequency, and duration influence forest productivity over time, and evaluated the role of functional identity and diversity in modulating forest responses. We analyzed forest productivity from 1985 to 2018 in a Mediterranean region of central Spain using generalized linear mixed models. Our estimates were based on biomass data resulting from integrating LiDAR, multispectral imagery, and forest inventory records from 748 plots. Our results indicated that the negative effects of the increased vapor pressure deficit and drought dimensions on forest productivity have intensified over time. Under extreme drought conditions, forests with higher functional diversity and dominated by moderately conservative species experienced smaller declines in productivity, whereas forests dominated by highly conservative species showed increasingly negative responses. This result may reflect repeated drought effects resulting in long stomatal closure periods and carbon starvation. Our findings highlight the increasing and negative impact of hotter droughts over time on Mediterranean forests. Altogether, the stabilizing role of functional diversity and identity in drought tolerance traits, such as cavitation resistance, should be considered in models addressing long-term climate change impacts on forest mitigation potential.Item Phase transitions of untilted fatty-acid Langmuir monolayers during isobaric heating and cooling: Interfacial rheology results(Physical Review E, 2025) Sánchez-Puga, Pablo; Tajuelo, Javier; Martínez Pedrero, Fernando; Guzmán Solís, Eduardo; Ortega Gómez, Francisco; Rubio, Miguel A.We study the two-dimensional melting of fatty acid Langmuir monolayers via the mechanical properties of their untilted phases, compact solid (CS), solid (S), and superliquid (LS). Taking the dynamic moduli as order parameters in isobaric temperature sweeps of behenic and arachidic acid monolayers, the CS-S and S-LS transitions appear as continuous transitions. However, a discontinuity appears in a high-order crossed susceptibility that involves the derivative of the dynamic moduli with respect to the control parameter (temperature). The critical value of the shear storage modulus at the melting temperature agrees with the prediction of the KTHNY theory, but the characteristic exponent does not.Item La formación del profesorado: elemento clave en la mejora de la convivencia escolar(Revista Digital de Educación: Observatorio Regional sobre la Formación Docente, 2014) Gómez Jarabo, InmaculadaEn el presente artículo mostramos algunos de los resultados más relevantes de la investigación llevada a cabo a lo largo del curso 2012/2013 sobre las actitudes, herramientas y el grado de preparación que tienen los profesionales de la educación (de las etapas de Infantil y Primaria) para poder intervenir en situaciones en las que la convivencia pacífica se ve amenazada y para atender adecuadamente a la diversidad (derivada del sexo y la cultura) y promover una convivencia saludable. Asimismo, reflexionamos sobre la adecuación de los actuales planes de formación del profesorado a las necesidades de nuestro contexto social y educativo y realizamos algunas propuestas de mejora de los mismos en relación a la convivencia escolar.Item Divergence of Leptin Receptor and Interleukin-6 Receptor Subunit b in Early Vertebrate Evolution and Physiological Insights from the Sea Lamprey(Molecular Biology and Evolution, 2025) Gong, Ningping; Barany Ruiz, André; Norstog, Jessica L.; Larhammar, Dan; Björnsson, Björn Thrandur; Regish, Amy M.; McCormick, Stephen D.; Sheridan, Mark A.Current knowledge of class-I cytokine receptors comes primarily from studies in jawed vertebrates (gnathostomes), and their origin and evolution remain unresolved. In this study, we identified a leptin receptor-like sequence (LepRL) and three interleukin-6 receptor subunit b-like sequences (IL6RBL) from a jawless vertebrate (cyclostome), the sea lamprey (Petromyzon marinus). Based on structural, phylogenetic, and syntenic analyses, we deduced that these lamprey receptors are likely distinct ohnologs to gnathostome LepR and IL6RB-related receptors, respectively, that arose in the two rounds of vertebrate whole-genome duplication (1R and 2R). Notably, lamprey LepRL likely originated from a different 1R progenitor than the one giving rise to gnathostome LepR during cyclostome hexaploidization. Differential patterns in mRNA expression of LepRL and IL6RBLs were observed among adult tissues, during larval metamorphosis, and in response to juvenile feeding. Feeding stimulated hepatic expression of LepRL and IL6RBL (namely, IL6RBL1) mRNAs in correlation with upregulation of insulin-like growth factor mRNA, whereas brain LepRL and IL6RBL1 mRNA expression was correlated positively with neuropeptide Y but inversely with intestinal content in fed juveniles. Notably, these observations along with immunolocalization of LepRL in the hypothalamus suggest a role of leptin signaling in regulating energy balance that is conserved among vertebrates. Additionally, seawater exposure stimulated branchial LepRL expression coincident with increased expression of ion transporters in ionocytes, indicating a role of leptin signaling in osmoregulation. These findings provide new insight into the early evolution of class-I cytokine receptors and reveal diverse functions of the leptin signaling system in jawless vertebrate.Item Grazing Modulates the Multiscale Spatial Structure of Dryland Vegetation(Global Change Biology, 2025) Pichon, Benoît; Kéfi, Sonia; Gounand, Isabelle; Gross, Nicolas; Le Bagousse‐Pinguet, Yoann; Guerber, Josquin; Eldridge, David; Valencia Gómez, Enrique; Plaza, César; Martínez‐Valderrama, Jaime; Saiz, Hugo; Ochoa, Victoria; Gozalo, Beatriz; Guirado, Emilio; García‐Gómez, Miguel; Gaitán, Juan J.; Asensio, Sergio; Mendoza, Betty Josefina; Donnet, Sophie; Maestre, Fernando T.Plants can facilitate their local environment and create a two-phase spatial structure of vegetation and bare soil in drylands, which largely influences ecosystem functioning. Although an increasing number of studies have examined how global change drivers like aridity influence vegetation spatial structure in drylands (e.g., the patch size distribution), it remains unclear how grazing impacts differ from those of climatic gradients, how these effects vary with herbivore feeding habits, and which plant-level traits—such as size and life form—mediate these spatial responses. Here, we coupled spatial vegetation pattern analyses of ecosystem images with field data analyses of the size distribution and dominant life forms of plants from 326 plots sampled across 25 countries and six continents to explore the effects of herbivores on the spatial structure of dryland vegetation. The effects of herbivores on vegetation spatial structure were opposite to the effects of aridity. Specifically, vegetation in grazed areas was clustered into larger patches, with fewer small patches, which skewed the patch-size distribution towards larger patches. These effects differed between browsing and grazing herbivores. Grazing effects were partially explained by the fact that grazing reduced average plant size, increased shrub density, and promoted facilitation among species of contrasting sizes. Similar effects were also confirmed by using model simulations that accounted for positive plant interactions. By linking remotely sensed images, a global field survey, and a mathematical model, our study uncovers the species-level mechanisms by which herbivores shape ecosystem-level spatial patterns and provides insights into the consequence of herbivory pressure on the resilience of drylands.Item Facebook use and chronotype: Results of a cross-sectional study(Chronobiology International, 2015) Blachnio, Agata; Przepiorka, Aneta; Díaz Morales, Juan FranciscoFacebook has become the most popular social networking site round the world. In seeking an explanation for this phenomenon, individual differences in circadian functioning seem to be an interesting issue. The main aim of this study was to examine the potential associations between morningness/eveningness and Facebook use (intrusion and intensity). The participants were 663 Facebook users. The Facebook Intrusion Questionnaire, Facebook Intensity Scale and the Composite Scale of Morningness were used. Our results indicate that chronotype is negatively related with Facebook usage. Eveningness people use Facebook intensively and their Facebook use is more intrusive. Moreover, eveningness in combination with young age predicted Facebook intensity.Item Fossil ribcages of Homo sapiens provide new insights into modern human evolution(Communications Biology, 2025) López Rey, José M.; Crevecoeur, Isabelle; May, Hila; Nadel, Dani; Palancar, Carlos A.; Gómez Recio, Marta; García Martínez, Daniel; Bastir, MarkusRecent research on the Nariokotome Boy’s ribcage suggests the slender thorax of modern H. sapiens is a derived condition. However, since digital ribcage reconstructions of fossil H. sapiens are not available yet, it is unknown whether these individuals would have had a primitive or derived thorax. To address this issue, we first reconstructed the ribcages of Nazlet Khater 2, Ohalo II H2, Dolní Věstonice 13, and Ötzi. We used geometric morphometrics to compare them to 59 recent H. sapiens and three other Homo fossils (Nariokotome Boy, Kebara 2, Shanidar 3). Fossil H. sapiens ribcages exhibit the typical globular proportions of recent humans. Additionally, size and shape seem to be climate-dependent: smaller, cylindrical ribcages in warmer and more temperate climates (Nazlet Khater 2, Ohalo II H2) contrasted with larger, broader ribcages in colder climates (Dolní Věstonice 13). The ribcage of Ötzi presented mixed features, something that could have been beneficial for seasonal alpine transhumance. This suggests H. sapiens ribcage morphology encompasses both slender and stockier forms, highlighting that human anatomical variation might be more complex and context-dependent than previously thought.Item The BEARS sleep screening tool: Sex, age and circadian typology differences in Spanish adolescents(Sleep Medicine, 2025) Manjón Caballero, José Luis; Díaz Morales, Juan FranciscoBackground: The aim of this study was to carry out a detailed analysis of the BEARS, providing data on the prevalence of sleep problems according to sex, age and circadian typology in a large sample of Spanish adolescents. Methods: A total of 2182 adolescents aged 12–17 years completed the BEARS sleep problem questionnaire, which measures bedtime problems (B), excessive daytime sleepiness (E), awakenings during the night (A), regularity and duration of sleep (R), and snoring (S), and the Morningness-Eveningness Questionnaire, which differentiates between evening, intermediate and morning types. Results: The results indicate a higher prevalence of sleep problems, including late bedtimes on both school days (85 %) and weekends (84 %), excessive daytime sleepiness (47.8 %), sleep less than 8 h during school days (42 %), problems falling asleep at bedtime (32.6 %) and struggling to return to sleep after nocturnal awakenings (26.2 %). Conclusions: The prevalence of these problems was greater in girls and in evening types. These findings highlight the need to consider individual differences in the clinical management of sleep problems in adolescents.Item Food reward entrainment increases mealtime anxiety in goldfish via a ghrelin-dependent mechanism(Scientific Reports, 2025) Herrera Castillo, Lisbeth Carolina; Saiz Aparicio, Nuria; Pedro Ormeño, Nuria De; Isorna Alonso, EstherFood anticipatory activity (FAA), the increase in locomotor activity prior to a scheduled feeding time, is linked not only to energy demands but also to food reward expectations. However, the mechanisms behind FAA remain unclear. We hypothesize that FAA induces anxiety due to reward anticipation. To test this, anxiety-like behavior was assessed in goldfish using open field and black-and-white preference tests under different feeding conditions and daytimes. Increased thigmotactic and scototactic behavior during FAA, compared to the post-FAA period, was observed, even in animals under constant light. Additionally, an unexpected meal did not reduce anxiety, while more hours of fasting did not increase it, suggesting that FAA is an anxiogenic state driven by a food-entrained oscillator rather than energy status. Ghrelin signaling was further explored using two antagonists, both of which reduced anxiety-like behavior when administered during FAA. Moreover, ghrelin administration induced anxiety-like behavior that was reversed by co-injection with an antagonist, supporting its anxiogenic role. These findings suggest a shared neural mechanism between FAA and anxiety, mediated by ghrelin. The possible involvement of ghrelin in activating dopamine-reward circuits in teleosts should be explored in future studies to gain further insight into the neurobiological basis of food anticipatory activity.Item Las biografías de Esquilache: Leopoldo de Gregorio (1699-1785), más allá del motín(Rivista MO.DO. Rivista di storia, scienze umane e cultural heritage, 2025) Recio Morales, ÓscarLeopoldo de Gregorio dio nombre a la revuelta más importante en la España del siglo XVIII: el motín contra Esquilache de 1766. Contamos con una amplia bibliografía sobre sus causas, su desarrollo y consecuencias, pero sobre su principal protagonista, el siciliano marqués de Esquilache, subsisten numerosas lagunas biográficas. A pesar de que su popularidad llega hasta nuestros días, todavía no disponemos de una biografía académica que cubra toda su trayectoria vital y profesional en Italia y en España. En las siguientes páginas estudiamos las aproximaciones a su figura desde el ámbito académico, artístico y cultural, y contextualizamos al personaje en el debate historiográfico sobre su figura y su época.