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«Venidos a tal estado de necesidad»: crédito y endeudamiento nobiliario en la Península Ibérica al final de la Edad Media
Get PDFLos días 14 y 15 de diciembre de 2023, en el Centro de Investigación Micaela Portilla de la Universidad del País Vasco en Vitoria-Gasteiz, celebramos una reunión académica que se había ido gestando en el marco de la estrecha colaboración que mantienen desde hace años dos grupos de investigación con sede en la Universidad de Zaragoza y en la Universidad del País Vasco dedicados al estudio de las transformaciones económicas, políticas y sociales durante los últimos siglos medievales1. Los textos que aquí se presentan son el resultado de las contribuciones que nuestras compañeras y compañeros han elaborado después de los debates que mantuvimos aquellos días..
Current Knowledge on Novel Semi-Arid Photovoltaic Ecosystems, Their Impacts on Biodiversity and Implications for the Sustainability of Renewable Energy Production
Get PDFThe transition from fossil fuels to renewable energy is fundamental to the mitigation of global climate change. Renewable power capacity is increasing globally, and solar photovoltaics will be the dominant renewable energy source by 2050. Photovoltaic parks (PVPs) require great expanses of land, usually in drylands, creating impacts that can compromise the sustainability of surrounding ecosystems and PVPs. But both novel ecosystems in PVPs and the effect of PVPs on ecosystems are rarely studied. This paper reviews the current knowledge on the impact of PVPs on arid and semi-arid ecosystems and describes the structure and functioning of these novel ecosystems, including changes in microclimatic conditions, soil properties, vegetation and fauna, and shows how these factors hinder the full recovery of ecosystems in PVPs. Ensuring that we do not sacrifice biodiversity for clean energy production restoration is necessary; hence, we address the limitations and challenges of restoring ecosystems within PVPs and suggest the use of modern ecological restoration techniques and the incorporation of grazing into rational planning. More research is needed to fully understand the long-term impacts and interactions of PVPs with the environment, the evolution of novel ecosystems in PVPs and the restoration techniques needed to achieve the long-term sustainability of these infrastructures
Mejorando la competencia matemática. Una experiencia de trabajo en el IES Pilar Lorengar
Get PDFLa experiencia que se presenta en este artículo se lleva a cabo en el IES Pilar Lorengar situado en el barrio La Jota de Zaragoza; comenzó durante el curso 2018-2019, centrada en 1º ESO en la asignatura de matemáticas y ha dado pie a continuar con un cambio metodológico hasta el día actual. El departamento estaba entonces formado por 8 personas con inquietudes cercanas en cuanto a la ense-ñanza y el aprendizaje de las matemáticas..
Differences in kinematic and muscle activity between ACL injury risk and healthy players in female football: influence of change of direction amplitude in a cross-sectional case–control study
Get PDFBackground and Objectives: Anterior cruciate ligament (ACL) injury rates remain high and have a significant impact on female football players. This study aims to evaluate knee kinematics and lower limb muscle activity in players at risk of ACL injury compared to healthy players through three side-cutting tests. It also investigates how the amplitude of a change in direction influences stabilization parameters.
Materials and Methods: A crosssectional case–control study was conducted with 16 second division female futsal players (23.93 ± 5.16 years), divided into injured (n = 8) and healthy groups (n = 8). Injured players had a history of non-contact knee injury involving valgus collapse, without undergoing surgical intervention. Three change of direction tests, namely the Change of Direction and Acceleration Test (CODAT), Go Back (GOB) test, and Turn (TURN) test, were used for evaluation. The peak and range of knee joint angles and angular velocities across three planes, along with the average rectified and peak envelope EMG signals of the Biceps Femoris (BF), Semitendinosus (ST), Vastus Medialis (VM), and Lateral Gastrocnemius (LG), were recorded during the preparation and load phases. Group differences were analyzed using two-factor mixed-model ANOVA with pairwise comparisons. Statistical significance was set at p < 0.05. Results: Injured players demonstrated lower external tibial
rotation angular velocity and a greater range of motion in tibial external rotation compared to healthy players. Additionally, the injured group showed significantly higher average rectified muscle activity in VM and LG both increased by 4% during the load phase. The CODAT and TURN tests elicited higher BF and VM muscle activity, compared to the GOB test. The TURN test also showed greater extension angular velocity in the sagittal plane.
Conclusions: The results revealed differences in knee kinematics and muscle activity between players at risk of ACL injury and healthy players, influenced by the amplitude of directional changes. Players altered transverse plane mechanics and increased VM and LG activation during LOAD may reflect a dysfunctional motor pattern, while the greater sagittal plane angular velocity and VM and BF activation from the CODAT and the TURN test highlight their higher potential to replicate ACL injury mechanisms compared to the GOB test
A new Cambrian stem-group echinoderm reveals the evolution of the anteroposterior axis
Get PDFEchinoderms are among the most morphologically distinctive animal phyla, encompassing familiar forms like starfish and sea urchins. Uncovering how their unique pentaradial body plan evolved from a bilaterally symmetrical ancestor has long proved challenging, as this involved fundamental changes to adult morphology and body plan development, associated with a complete reorganization of the anteroposterior (A-P) axis,1,2,3 obfuscating homologies between disparate groups.4,5 This has greatly limited our understanding of one of the most radical transformations in bilaterian evolutionary history.6,7,8 Here, we describe a new bilaterally symmetrical echinoderm, Atlascystis acantha, from the Cambrian of Morocco.9 This is the oldest bilaterally symmetrical echinoderm and the first with this body plan known from different ontogenetic stages, allowing us to elucidate mechanisms of its growth. This demonstrates that Atlascystis possessed ambulacra—structures accommodating extensions of the characteristic echinoderm water vascular system—providing a clear point of homology between Atlascystis and radially symmetrical forms. By integrating the Cambrian fossil record and our new phylogeny with developmental biology,10 we uncover how changes to the ancestral bilaterian A-P patterning network alongside stepwise morphological transformations gave rise to the pentaradial structure of extant echinoderms, transforming our understanding of the origin and earliest evolution of this major animal phylum
Organosilicon molecules bind to the intrinsically disordered protein NUPR1 by clamping its hot-spots
Get PDFThe nuclear protein 1, or NUPR1, is an intrinsically disordered protein (IDP) involved in the development and progression of pancreatic ductal adenocarcinoma (PDAC). We have previously developed drugs capable of binding at the two hot-spot regions of NUPR1, around residues Ala33 and Thr68, hampering its interactions in cellulo. In this work, we synthesized new organosilicon molecules targeting those key hot-spots. The compounds were obtained by an acid-catalyzed intramolecular cyclization of a starting alkenol that contains a silyl group attached to the double bond. Binding between the silyl compounds and NUPR1 involved the two hot-spots, as shown by 2D 1H–15N HSQC NMR. Molecular simulations clarified that the binding relies on a loose clamp mechanism of the ligands towards the hot-spots. The dissociation constants (Kd) were around 20 μM, as measured by several biophysical techniques. However, studies in cellulo with PDAC cells did not show a decrease of cell viability upon treatment with the compounds; furthermore, proximity ligation assays in cellulo with a natural partner protein of NUPR1, G3BP, did not show a significant level of interfering in such interaction when silyl compounds were present, probably due to the high hydrophobicity of the designed compounds. Thus, in the case of NUPR1, moderate-to-high drug binding affinities (Kd < 10 μM) in vitro and a higher hydrophilicity are necessary to hamper protein-protein interactions in cellulo. As a more general conclusion, in vitro binding of ligands to the protein hot-spots is a necessary condition in the drug design targeting IDPs, but it is not enough to guarantee inhibition of their interactions in cellulo
Underpinnings of breastfeeding motivation: A systematic review
Get PDFBackground. Breastfeeding is a fundamental practice for child and maternal health, recommended by the World Health Organisation (WHO) and the United Nations International Children's Emergency Fund (UNICEF). However, despite its proven benefits, exclusive breastfeeding rates remain suboptimal in many countries. Mothers' motivation plays a crucial role in the initiation, continuation and prolongation of breastfeeding, but various factors can negatively influence this motivation. Aim. This research explores the complex motivational dynamics surrounding breastfeeding, encompassing both the intrinsic motivation of mothers and the motivational interventions of health professionals.
Methods. A systematic review encompassing both qualitative and quantitative inquiries, was undertaken. Research questions were formulated, and a search strategy devised, to review PubMed, Scopus, and Web of Science repositories, with a retrospective scope spanning the past three decades, applying filters and eligibility criteria. We included scientific articles whose participants were healthy mothers aged 18-48 years with uncomplicated eutocic deliveries, together with their healthy full-term infants. The study aimed to analyze the motivation for breastfeeding from the prenatal stage to prolongation beyond the two years recommended by the WHO.
Findings. A total of 23 studies, from a variety of perspectives and sociocultural contexts, were identified and recovered. Average breastfeeding duration was 2.73 months shorter than the recommended 6-month period. Deciding to breastfeed "as long as possible" and prior breastfeeding experience were associated with meeting breastfeeding expectations. Instead, maternal age, caesarean delivery, and socio-environmental factors negatively affected the breastfeeding process. Our findings highlighted intrinsic maternal motivations and the impact of healthcare professional interventions, revealing the complex interplay of psychological, social, and cultural factors in breastfeeding decisions.
Conclusion. An exhaustive typological analysis of maternal motivation throughout breastfeeding phases is feasible. Motivational dynamics may vary, concretely influencing breastfeeding exclusivity and duration. These dynamics are foreseen by maternal intent and bolstered by self-efficacy conducive to successful progression. Furthermore, sociocultural and clinical variables modulate motivational pathways. In-depth analysis allows for more effective professional interventions within the framework of humanized care and the development of innovative health plans and policies
Grazing Modulates the Multiscale Spatial Structure of Dryland Vegetation
Get PDFPlants 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
Praseodymium and gadolinium doped ceria as oxygen electrode for solid oxide cell applications
Get PDFhis study analyzes the structural and electrochemical properties of praseodymium- and gadolinium-doped ceria (CPGO) samples formed by the sintering reaction of Pr2NiO4+δ (PNO) and Ce0.9Gd0.1O2−δ (GDC). X-ray powder diffraction analysis confirmed a single-phase cubic CPGO structure as a primary phase. The cationic compositions were determined using energy dispersive spectroscopy (EDS) in a scanning transmission electron microscope (STEM), while core-loss electron energy-loss spectroscopy (EELS) was used to determine the valence of Ce and Pr. The compatibility between thermal expansion coefficients validated their integration with electrolytes at the typical Solid Oxide Cell (SOC) operation temperatures. Oxygen chemical diffusion and surface exchange coefficients were investigated using the electrical conductivity relaxation (ECR) method at intervals of partial oxygen pressures between 0.10 and 0.21 atm and 600 °C and 800 °C. Finally, the samples were tested in symmetrical cells by electrochemical impedance spectroscopy (EIS) between 700 °C and 850 °C. A polarization resistance of 0.17 Ω cm2 at 850 °C was obtained for CPGO air electrodes formed by sintering a mixture of 80% by weight of GDC and 20% by weight of PNO. These findings confirm that PNO–GDC mixtures forming CPGO oxides are excellent candidates for SOC applications.
En este estudio se analizan las propiedades estructurales y electroquímicas de composites formados por la reacción de sinterización de Pr2NiO4+δ (PNO) y Ce0.9Gd0.1O2-δ (GDC). Los refinamientos de Rietveld de los patrones de difracción de rayos X confirmaron una estructura cúbica monofásica de ceria dopada con praseodimio y gadolinio (CPGO) como fase primaria. Las composiciones catiónicas de CPGO se determinaron mediante espectroscopia de dispersión de energía (EDS) en un microscopio electrónico de transmisión de barrido (STEM), mientras que se utilizó espectroscopia de pérdida de energía de electrones (EELS) para determinar la valencia de Ce y Pr. La compatibilidad entre coeficientes de expansión térmica validó la integración de los electrodos con electrolitos a las temperaturas de operación típicas de las pilas de óxido sólido (SOC). Los coeficientes de difusión química de oxígeno y de intercambio superficial se determinaron mediante relajación de la conductividad eléctrica (ECR). Finalmente, se caracterizaron celdas simétricas mediante espectroscopia de impedancia electroquímica (EIS), obteniendo una baja resistencia de polarización de 0.17 Ω cm2 a 850 °C para electrodos de aire compuestos por 80% de GDC y 20% de PNO en peso. Estos hallazgos confirman que los electrodos de CPGO son excelentes candidatos para aplicaciones SOC
The effect of education, diacutaneous fibrolysis, and self-mobilization on sleep quality in patients with carpal tunnel syndrome waiting for surgery: A randomized controlled trial
Get PDFBackground. Carpal tunnel syndrome (CTS) patients experience a wide range of sleep complaints. However, little evidence exists on how conservative treatment can improve sleep quality in these patients.
Purpose. To determine the effectiveness of a multimodal physiotherapy approach based on sleep symptoms and quality in patients suffering from CTS included in a surgery waiting list.
Study Design. A randomized controlled trial.
Methods. CTS patients included in surgical waiting list of Spanish Public Health System were recruited. Patients were randomized into an education, diacutaneous fibrolysis, and self-mobilization treatment over 3 weeks (n = 20) or a control group (n = 22). Nocturnal symptoms, Medical Outcome Study Sleep Scale, Boston Carpal Tunnel Questionnaire, and sensitivity of the hand were assessed after treatment, at 3- and 6-months follow-up. A general linear model of repeated measures was performed.
Results. Nocturnal symptoms (p < 0.1; d = 1.0-1.5) and Boston Carpal Tunnel Questionnaire (p = 0.01; d = 1.0-1.1) were improved in favor of intervention group at each follow-up. Also, sensitivity of the first three fingers showed better results for intervention group at 3- (p = 0.021; d = 0.5) and 6-months (p = 0.036; d = 0.8) follow-up. Five of the eight items in the Medical Outcome Study Sleep Scale reported significant differences at 6-month against the control group (p < 0.1). There was a significant increase in the amount of sleep in the intervention group (p = 0.006; d = 0.7). Finally, physical activity and splint influenced the results of nocturnal symptoms and awaken short of breath and headache. Conclusions. Education, diacutaneous fibrolysis, and self-mobilization may improve night-time symptoms and sleep quality in CTS patients awaiting surgery. Patients included were mainly severe, had associated comorbidities, and under-represented patients in conservative treatment studies