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Macrocyclic NHC Ligands in Hoveyda-Type Ru Alkene Metathesis Catalysts: Only Sterics?
No full textThe integration of macrocyclic structures within N-heterocyclic carbene (NHC) ligands in Hoveyda-type catalysts presents a pioneering strategy to enhance selectivity in cross-alkene metathesis. This approach falls within a promising paradigm for avoiding undesired homocouplings between reacting alkenes and introducing site-selectivity into the cross metathesis process. This paper presents a computational study that aims to provide an improved understanding of the impact of these ligand modifications on stability, sterics, and activity, focusing on the precatalyst activation and cross-metathesis. The traditional Hoveyda-type catalyst is compared alongside two recent macrocyclic systems for which experimental data is available. Higher activation barriers in the macrocyclic systems are consistent with the reduced activity observed in these systems. Additionally, a noncovalent interaction component was found to facilitate the selective pathway, in conjunction with the already expected steric descriptors. These results highlight the potential of macrocyclic NHC ligands to enhance catalyst performance, not only offering chemoselectivity based on alkene size, but a potential for stereoselectivity capacity arising from the macrocycle-induced electronic effectsA.P. is a Serra Húnter Fellow. We thank the Spanish Minis-terio de Ciencia y Universidades (MICIU) for projects PID2021-127423NB-I00 and PID2024-155989NB-I00 and the Generalitat de Catalunya for project 2021SGR623. S.T.D. thanks the National Science Foundation (NSF) through grant CHE-1900392.
Open Access funding provided thanks to the CRUE-CSIC agreement with AC
Talent matemàtic: propostes pel desenvolupament de la competència matemàtica a partir del joc
No full textEl treball s’enfoca en el talent matemàtic a les aules de primer de l’escola Les Mèlies de Vilafant. Davant la diferència de ritmes d’aprenentatge es vol donar resposta a les necessitats educatives dels infants que es troben per sobre la mitjana. L’estudi del fenomen és a partir d’un instrument d’anàlisi. Davant la identificació dels casos de talent matemàtic s’han dissenyat i aplicat propostes lúdiques. Les dades qualitatives obtingudes a la graella d’observació han permès valorar l’adequació. El talent es desenvolupa per les oportunitats que reben, per tant, tenen el dret de rebre recursos necessaris en funció de les seves capacitats.This project is focus on the mathematical talent within first-grade groups of Les Melies in Vilafant. Facing the different learning rhythms students have, the project aims to fulfil the educational needs of children with above-average abilities. The research of this phenomen is done through an analysis instrument. Once identified cases of mathematical talent, playful proposals have been designed and applied. The qualitative data obtained in the observation grid allowed to asses its adequacy. The talent is developed through the choices given to the children so, all of them have the right to receive the necessary resources regarding their own abilities
Proposta gamificada amb extensió extraescolar per potenciar la resistència aeròbica i fomentar l’activitat física en alumnes de 3r de primària
No full textLa recerca analitza l'impacte d'una Situació d'Aprenentatge en la resistència aeròbica i l'adherència a l'activitat física en alumnes de 3r de primària, emprant la gamificació combinada amb una extensió de reptes motrius opcionals fora de l'horari escolar per promoure hàbits actius. S’utilitza un enfocament qualitatiu basat en un estudi de cas amb una mostra de 50 alumnes de l’Escola Cor de Maria d’Olot. Es recullen dades amb el “6-minute walk test”, qüestionaris PAQ-C adaptats, registres d’adherència als reptes opcionals i instruments per avaluar la intervenció docent i la implementació de la proposta. Els resultats mostren una millora no significativa en resistència aeròbica, però un augment en l’adherència, especialment entre nenes. Es conclou que la proposta fomenta hàbits actius a curt termini, amb necessitat d’adaptacions per promoure una implicació per part de tot l’alumnat.This study analyzes the impact of a learning situation on aerobic endurance and adherence to physical activity in 3rd-grade primary students, employing gamification combined with optional motor function challenges after school hours to promote active habits. A qualitative approach based on a case study was used, with a sample of 50 students from Cor de Maria School in Olot. Data collection tools included the 6-minute walk test, adapted PAQ-C questionnaires, adherence records for the optional challenges and instruments to evaluate the teaching intervention and the implementation of the proposal. The results show a non-significant improvement in aerobic endurance but an increase in adherence, especially among girls. It is concluded that the proposal encourages active habits in the short term, with a need for adjustments to promote the involvement of all students
Combined Systemic and cutaneous ovalbumin-aluminum sensitization triggers thermal hyperalgesia, spinal gliosis, and nociceptive nerve fibers sprouting in mice
No full textBackground/Objectives: This study investigates whether systemic ovalbumin-aluminum sensitization followed by cutaneous challenge induces thermal hyperalgesia and spinal cord gliosis in mice. Methods: Adult female ICR-CD1 mice received ovalbumin-aluminum salt solution intraperitoneally on days 0, 7 and 14, and subcutaneously with daily skin application via brush during days 15-21, 28-35 and 42-49. Control animals received saline. Plantar thermal hyperalgesia was assessed on days 21, 35 and 49. On day 49, tissues (dorsal skin, spinal cord, footpads) were harvested after perfusion and processed histologically to detect mast cells, astrocytes, microglia, afferent fibers and intraepidermal nerve profiles. Results: Ovalbumin-treated mice displayed thermal hyperalgesia, increased astrogliosis, and reactive microglia in the spinal cord, and expanded CGRP- and IB4-immunoreactive fiber areas. In footpads, CGRP-positive intraepidermal nerve profile density was elevated, and dorsal skin showed increased mast cell density compared to controls. Conclusions: Combined systemic and cutaneous ovalbumin-aluminum sensitization induces skin in- flammation, spinal gliosis, and nociceptive fiber sprouting in both central and peripheral sites, which likely contribute to the observed thermal hyperalgesi
Prueba de la relación causal en el delito ecológico base: problemas y propuestas de solución
No full textEl presente trabajo analiza las dificultades inherentes a la determinación y prueba del nexo causal en el delito ecológico base, regulado en el artículo 325.1 del Código Penal español. A partir del análisis doctrinal y jurisprudencial, se constata la configuración predominante de este delito como un delito de peligro hipotético. Sin embargo, esta calificación plantea desafíos conceptuales y probatorios, especialmente en la determinación el grado de probabilidad que se exige para considerar penalmente relevante dicho riesgo y en la ausencia de criterios cuantitativos verificables. Se propone la adopción de un modelo de causalidad general, sustentado en la prueba científica y en el uso de la probabilidad estadística, que permita fundamentar de manera objetiva el juicio de peligrosidadThis paper examines the inherent difficulties in determining and proving the causal link in the basic environmental offense, as regulated in Article 325.1 of the Spanish Criminal Code. Based on doctrinal and case law analysis, it is confirmed that this offense is predominantly classified as a hypothetical endangerment crime. However, this classification presents conceptual and evidentiary challenges, particularly regarding the degree of probability required for the risk to be considered criminally relevant, and the lack of verifiable quantitative criteria. The paper proposes the adoption of a general causality model, grounded in scientific evidence and the use of statistical probability, to objectively support the assessment of dangerousness1
The Oxytocin Receptor in Spermatozoa May Originate From Both Spermatogenesis and Epididymal Maturation, and Regulates Capacitation
No full textBackground: The oxytocin receptor (OR) is a G-protein-coupled receptor recently identified in human spermatozoa, whose origin and role in sperm physiology remain unknown. Objectives: In this study, using the pig as a model, we examine the presence of the OR in ejaculated spermatozoa through immunofluorescence and immunoblotting, and investigate the receptor's origin in the male gamete via immunohistochemistry in testicular and epididymal tissues. Additionally, we assess the involvement of the OR in in vitro capacitation and the acrosome reaction by utilizing physiological concentrations of agonists (oxytocin and carbetocin) and an antagonist (L-371,257). Results: The results indicate that, in addition to the expected presence in ejaculated spermatozoa, the OR is expressed during spermatogenesis. Besides, this receptor is found in Leydig and Sertoli cells, as well as in the principal, basal, and apical cells of the epididymis. Furthermore, our data suggest that, during epididymal maturation, the OR could be incorporated in spermatozoa via extracellular vesicles within the apical blebs. The OR is involved in sperm capacitation, as the combination of the antagonist (L-371,257) and the agonist (carbetocin) increases intracellular calcium levels and membrane lipid disorders, which are known as capacitation markers. Conclusions: The presence of the OR in mammalian spermatozoa could originate from both spermatogenesis and epididymal maturation. Moreover, in the male gamete, this receptor regulates sperm capacitation by interacting with its ligand in the female reproductive tractResearch funding: European Union-Next Generation EU Funds and University of Murcia. Grant Number: 181/MSJD/22; Ministry of Science, Innovation and Universities. Grant Numbers: PID2020-113320RB-I00, PRE2021-098896; Catalan Institution for Research and Advanced Studies. Grant Number: ICREA-Academia and Agency for Management of University and Research Grants. Grant Number: 2021-SGR-00900Open Access funding provided thanks to the CRUE-CSIC agreement with Wile
Managing Blood Glucose in Premature Neonates via Parenteral Nutrition: In-silico Evaluation
No full textPrometeus (Preterm Brain-Oxygenation and Metabolic EU-Sensing: Feed the Brain) develops innovative technology for personalized nutrition in premature neonates. Central to this is the Nutritional Clinical Advisor, an adaptive algorithm providing optimal parenteral nutrition plans to enhance brain oxygenation. This study tests a closed-loop PID controller for regulating glucose levels in virtual neonates born preterm, offering insights into its effectiveness and guiding future NCA development to support neonatal careThe authors would like to express their gratitude to all the physicians involved in the Prometeus project for their valuable discussions and insights during its developmen
Brincar além dos muros: una experiència a/r/togràfica sobre els rols de gènere en una brinquedoteca escolar
No full textAquest treball de fi de grau analitza com una instal·lació artística en una brinquedoteca,
un espai educatiu dedicat al joc simbòlic i experimental, pot promoure la reflexió crítica
sobre els rols de gènere en la infància. L’estudi s’inscriu en una perspectiva qualitativa,
integrant dimensions pedagògiques i artístiques. Concretament, es fonamenta en dues
aproximacions clau en la recerca artística i educativa: la Investigació Basada en les Arts
(IBA) i l’A/r/tografia, emprant una proposta de mediació cultural per qüestionar les
normes de gènere en el joc.Este trabalho de conclusão de curso analisa como uma instalação artística em uma
brinquedoteca —espaço educativo voltado ao jogo simbólico e experimental— pode
promover a reflexão crítica sobre os papéis de gênero na infância. O estudo insere-se
numa perspectiva qualitativa, integrando dimensões pedagógicas e artísticas.
Fundamenta-se em duas abordagens centrais na pesquisa em arte e educação: a
Investigação Baseada nas Artes (IBA) e a A/r/tografia, por meio de uma proposta de
mediação cultural que questiona normas de gênero no brincar
Blood-based biomarkers in centenarians and non-centenarians: a matched, population-based retrospective cohort study using primary care records in Catalonia, Spain
No full textThe global increase in life expectancy has sparked growing interest in the factors that contribute to exceptional longevity. Between 1990 and 2015, the number of centenarians worldwide more than quadrupled. This study aimed to analyse the relationship between blood-based biomarkers and the likelihood of reaching 100 years of age in Catalonia (2015–2022), and to examine how biomarker variations during COVID-19 affected longevity. Using a retrospective cohort study based on primary care electronic health records from Catalonia, we compared centenarians with individuals aged 92 or older who died before reaching 100 years of age. We analysed anaemia, cholesterol, glycemia, kidney function, and liver function biomarkers. We employed multiple strategies to control for confounding including matching without replacement, adjusting for both observed confounders at both the individual and contextual level, and unobserved confounders, in particular spatial dependence. Our findings reveal that centenarians exhibit higher rates of chronic conditions, greater socioeconomic disadvantage, and increased neighbourhood inequality in urban areas. Biologically, longevity was linked to intermediate levels of ferritin and cholesterol, alongside lower glucose, creatinine, and uric acid levels. Glycaemic balance, indicated by HbA1c and fasting glucose, emerged as a key factor in survival to extreme old age. Additionally, biomarker improvements during the pandemic correlated with an increased likelihood of reaching centenarian age. These results emphasize the complex interplay between biological, behavioural, and contextual factors in determining longevity. While biomarkers provide valuable insights, they are insufficient indicators of healthy ageing. Future research should integrate multiple dimensions, among them, environmental, and social determinants for uncovering the mechanisms of longevityThis study was supported by the Department of Health of the Government of Catalonia through the 2021 grant call under the Strategic Plan for Research and Innovation in Health (2016–2020), in the Research Projects category focused on primary care (file code: SLT021/21/000002), and by the 2021 Call for Industrial Doctorates (DI 2021), AGAUR, Government of Catalonia.
Open Access funding provided thanks to the CRUE-CSIC agreement with Springer Natur
Spatial Analysis of Climate Risk in the West Bank, Palestine
No full textIn the developing countries (e.g., Palestine) a reliable assessment of climate vulnerability, exposure, and consequently risk is a key step in developing successful adaptation and mitigation plans. This study aims to examine the spatial distribution of climate risk across the different governorates of the West Bank (Palestine) by assessing climate-risk exposure. A GIS-based Multi-Criteria Decision Analysis approach was employed to estimate climate exposure across the West Bank governorates. Additionally, sensitivity analysis is used to explore the impact of indicator weight on the final climate-risk map. The climate-risk map was subsequently developed based on the exposure map, classifying the governorates into five risk categories: very high, high, moderate, low, and very low. This analysis revealed that 42% of the West Bank population resides in areas classified as having high to very high climate exposure, which corresponds to approximately 39% of the total land area. Conversely, about 21% of the West Bank area is categorized under low to very low risk conditions. By measuring risk based on this exposure, and considering vulnerability, it was determined that 82% of the population lives within areas identified as high to very high zones, underscoring the significant climate risk of populated regions. This study offers the first spatially explicit climate-risk assessment for the West Bank, applying a widely accepted approach that integrates vulnerability and exposure components. The results provide critical insights to inform targeted adaptation and mitigation efforts, supporting decision-makers in enhancing climate resilience across the region.The authors acknowledge the support from the Department of Research and Universities of the Generalitat de Catalunya through Consolidated Research Groups (ICRA-ENV 2021 SGR 01282), as well as from the CERCA progra