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Calcium homeostasis role in preserving sperm function and metabolic activity during liquid storage of pig semen
No full textCalcium (Ca2+) is known as a key regulator of sperm physiology, playing a crucial role in capacitation, hyperactivation, the acrosome reaction, and fertilisation. Despite this, whether it shapes the sperm's ability to withstand liquid preservation has not been addressed. Herein, we investigated how altering Ca2+ availability to pig sperm during storage at 17 °C affects their quality and metabolic activity. Using ethylene glycol tetraacetic acid (EGTA) and its membrane-permeable form (EGTA-AM), we selectively chelated either extracellular or intracellular Ca2+, respectively. Semen samples (n = 12 pools) were preserved in Beltsville Thawing Solution (BTS) under four conditions: control, Ca2+ supplementation, extracellular Ca2+ chelation, and intracellular Ca2+ chelation. Sperm function and metabolism were evaluated by flow cytometry and the oxygen consumption rate (OCR), whereas motility was assessed using Computer-Assisted Sperm Analysis (CASA). Ca2+ supplementation increased metabolic activity and induced capacitation-like changes, impairing sperm function. Intracellular Ca2+ chelation caused a sharp decline in motility and disrupted the metabolic balance, likely due to proton (H+) accumulation in the intermembrane space of mitochondria. In contrast, extracellular Ca2+ chelation preserved sperm viability, membrane integrity, and motility, while slightly reducing the OCR and the production of intracellular reactive oxygen species. These findings highlight the critical role of Ca2+ homeostasis in maintaining sperm function and suggest that fine-tuning Ca2+ dynamics - rather than full depletion - may improve the longevity and fertilising potential of liquid-stored pig semenThis work was supported by the Ministry of Science, Innovation and Universities, Spain (grants: PID2020-113320RB-I00, PRE2021-098896 and PID2023-149853OB-I00), the Regional Government of Catalonia (2021-SGR-0900), and the Catalan Institution for Research and Advanced Studies (ICREA)Open Access funding provided thanks to the CRUE-CSIC agreement with Elsevie
Global Assessment of the Cloud-Aerosol Transition Zone Using CALIPSO
No full textThe interactions between clouds and aerosols represent one of the largest uncertainties in assessing the Earth’s radiation budget, highlighting the importance of research on the transition zone (TZ) within the cloud-aerosol continuum. This study assesses the global distribution of TZ conditions, analyzes its optical characteristics, and determines the cloud or aerosol types most commonly associated with them, using the cloud-aerosol discrimination (CAD) score of the Cloud-Aerosol Lidar with Orthogonal Polarization (CALIOP) instrument on the CALIPSO satellite. The CAD score classifies clouds and aerosols by the probability density functions of attenuated backscatter, total color ratio, volume depolarization ratio, altitude, and latitude. After applying several filters to avoid artifacts, the TZ was identified as those atmospheric layers that cannot be clearly classified as clouds or aerosols, layers within the no-confidence range (NCR) of the CAD score, and cirrus fringes. The optical characteristics of NCR layers exhibit two main clusters: Cluster 1, with properties between high-altitude ice clouds and aerosols (e.g., wispy cloud fragments), and Cluster 2, with properties between water clouds and aerosols at lower altitudes (e.g., large hydrated aerosols). Our results highlight the significant ubiquity of TZ conditions, which appear in 9.5% of all profiles and comprise 6.4% of the detected layers. Cluster 1 and cirrus-fringe layers predominate near the ITCZ and in mid-latitudes, whereas Cluster 2 layers are more frequent over the oceans along the central West African and East Asian coasts, where elevated smoke and dusty marine aerosols are commonThe authors are grateful to the CALIPSO Science Team for their efforts and for making data products available. The CALIOP data were obtained from the NASA Langley Research Centre Atmospheric Science Data Center. This study has been funded through project NUBOLOSYTI (PID2023-149972NB-100) of the Spanish Ministry of Science and Innovation (MICINN). Jaume Ruiz de MORALES is supported by an IFUdG 2022 fellowship. The authors also thank the Satellite Climatology Group from KIT, for their helpful and thought-provoking discussions.
Open Access funding provided thanks to the CRUE-CSIC agreement with Springer Natur
On the use of chemical bonding descriptors in machine learning
No full textThis review explores recent advances in machine learning in chemistry, emphasizing mechanistic understanding, performance optimization, and emerging design strategies. Key developments include novel synthesis routes, computational screening, hybrid experimental–theoretical approaches, and in-situ characterization. The review highlights how these innovations improve efficiency, selectivity, and scalability while uncovering fundamental structure-activity relationships. Special attention is given to integrating predictive modeling and high-throughput experimentation, which accelerates discovery cycles and enables rational design. Comparative discussions of different methodologies reveal synergies between traditional approaches and data-driven tools. Despite remarkable progress, translating laboratory results into practical applications remains a central challenge. The review concludes by outlining open questions, methodological gaps, and future research directions aimed at developing robust, cost-effective, and environmentally sustainable solutionsA.P. is a Serra Húnter Fellow and thanks the Spanish Ministerio de Ciencia e Innovación for project PID2024-155989NB-I00 and the Generalitat de Catalunya for project 2021SGR623. M.G. thanks for being funded by the Deutsche Forschungsgemeinschaft (DFG, German Research Foundation) - 217133147/SFB1073, project C03Open Access funding provided thanks to the CRUE-CSIC agreement with Elsevie
Circular Economy Adoption in Manufacturing Firms: Evidence From Germany
No full textThis paper analyses Circular Economy (CE) practices adopted by manufacturing firms and explores whether the decision to adopt these practices differs in relation to manufacturing sector, company size, or having Environmental Management Systems (EMS) in place. Empirical data from 1191 German manufacturing firms was used to show that the circular practices companies adopt most are framed mainly within Recovery Field of Action (FA), followed by Distribution and Use. Findings highlight differences between sectors and point to a correlation between company size or having an EMS and a higher level of CE adoption, emphasising the need to tailor CE strategies to specific industrial sectors and company size, and highlighting the role EMS plays in facilitating the adoption of CEOpen Access funding provided thanks to the CRUE-CSIC agreement with Wiley
DNA barcoding reveals widespread co-occurrence of other chub species in the range of the endemic Catalan chub, Squalius laietanus
No full textThe Catalan chub, Squalius laietanus, was described in 2007 and has recently reached Vulnerable status on the IUCN Red List of Threatened Species. The assigned range for this species includes the lower course of the Ebro River in Spain and northwards to the Tech, Têt, Agly, and Massane Rivers in Southeastern France. In this study, 246 chub specimens caught at 15 sites in the nine main river basins of the Spanish range were barcoded by sequencing a 624 bp fragment of the mitochondrial COI gene. Squalius laietanus haplotypes were found in 68% of the fish caught. In a tributary of the Ebro River, all specimens (6%) were identified as the Tagus chub, S. pyrenaicus, another endemic Iberian chub species. The remaining fish (26%) had a haplotype typical of the European chub, S. cephalus, populations outside Spain. This haplotype was present in six sites in four basins, being particularly abundant in the Ebro River. Considering that Squalius species can hybridize with other native and non-native cyprinid species, the potential co-occurrence of several species in the same site or basin raises concerns about the real extent of an exclusive range for the Catalan chub and the integrity of its native gene pools throughout its range.This research was funded by the contract AG-2021-686 of the Inland Fisheries Service of the Autonomous Government of Catalonia (Servei de Pesca Continental, Departament d’Agricultura, Ramaderia, Pesca i Alimentació, Generalitat de Catalunya
Mechanism and optimization of ruthenium-catalyzed oxalamide synthesis using DFT
No full textThe oxalamide skeleton is a common structural motif in many biologically active molecules. These scaffolds can be synthesized via ruthenium pincer complex-catalyzed acceptorless dehydrogenative coupling of ethylene glycol and amines. In this study, we elucidate the mechanism of this oxalamide synthesis using density functional theory calculations. The rate-determining state is identified as the formation of molecular hydrogen following the oxidation of hydroxyacetamide to oxoacetamide. In predictive catalysis exercises, various modifications to the ruthenium pincer catalyst were investigated to assess their impact on the reactivityA. P. and A. P.-Q. are Serra Húnter Fellows. A. P. received ICREA Academia Prize 2019. We thank the Ministerio de Economía y Competitividad (MINECO) for project PGC2018-097722-B-I00 (to A. P.) and Ministerio de Ciencia e Innovación for PID2020-113711GB-I00 MCIN/AEI/10.13039/501100011033 and PID2023-146849NB-I00 (to A. P.-Q.). We thank the Spanish Government for the predoctoral FPU20/00707 grant to R. M.-C. Financial support from the “Ministère de la Recherche et des Nouvelles Technologies”, Normandie Université, University of Caen Normandie, CNRS, “Région Normandie”, and the LABEX SynOrg (ANR-11-LABEX-0029) is acknowledge
Enhancement of photoinduced reactive oxygen species generation in open-cage fullerenes
No full textPhotodynamic therapy is an important tool in modern medicine due to its effectiveness, safety, and the ability to provide targeted treatment for a range of diseases. Photodynamic therapy utilizes photosensitizers to generate reactive oxygen species (ROS). Fullerenes can be used as photosensitizers to produce ROS in high quantum yields. Open-cage fullerenes are a subclass of fullerenes characterized by a partially open structure, with one or more openings or apertures. The promising electrochemical properties of open-cage fullerenes motivated us to investigate their use for DNA-cleavage and ROS generation under visible light irradiation through type I electron transfer and type II energy transfer reactions. Our results show that open-cage C60 fullerenes are more efficient for photoinduced cleavage of DNA and ROS generation via both the type I electron transfer and type II energy transfer pathways than pristine C60 or a C60 pyrrolidine derivative without open-cage. The greater efficiency of ROS generation by open-cage C60 fullerene in type I and type II reactions can be attributed to the increased rate of the initial intersystem crossing process, resulting from larger total reorganization energies, as indicated by computationally calculated relative rates using the Marcus equation, and the lower reduction potential of the open-cage derivative 3, as determined by CV, which facilitates a more efficient generation of the corresponding radical anion (C60˙−)Agraïm el suport financer del Ministeri de Ciència, Innovació i Universitats espanyol (MCIN/AEI/10.13039/50110001103) (Projectes PID2023-147424NB-I00, PID2023-146849NB-I00, REDT3492-146849NB-I00, REDT3492-1492-146849-I00 a CC) i la Generalitat de Catalunya (Projecte 2021-SGR-623 i premi ICREA Academia 2024 a MS). AJS agraeix a la infraestructura informàtica d'alt rendiment de Polònia PLGrid (Centres HPC: ACK Cyfronet AGH) per oferir instal·lacions informàtiques i suport dins de la subvenció computacional núm. PLG/2023/016841. YY agraeix a la Fundació Nacional de Ciència Suïssa (projectes 173018 i 183660
Sedimentation patterns from turbidity currents associated to hydrodynamical transport modes
No full textTurbidity currents are mechanisms that transport sediment from continental landscapes into coastal areas and therefore into oceans, reservoirs and lakes. Turbulence at the head of the turbidity current maintains sediment particles in suspension provided the mixing is greater than the settling velocity of the particles being transported. However, both the depositional regimes of the particles in turbidity currents and the extent of the hydrodynamical regimes still need to be better related. Likewise, the associated sedimentary patterns need to be related to the type of particles that form a turbidity current. In this study, a set of lock-exchange experiments in a flume were conducted to determine the extent and development of a turbidity current composed of different granulometric sediments and sediment concentrations. Both the extent of the inertial regime and the onset of the self-similar regime were determined and found to be dependent on the d50 of the sediment and the Rouse number (i.e. the balance between particle sedimentation and mixing due to the gravity current development). The results obtained from the sedimentation patterns bring new knowledge in explaining the gradation of sediments in turbidites and its relationship to the longitudinal hydrodynamics of a turbidity current as it developsThis work was supported by the Ministerio de Economía y Competitividad of the Spanish Government through Grant PID2021-123860OB-I00. Open Access funding provided thanks to the CRUE-CSIC agreement with Elsevie
Bullying Victimization and Subjective Well-Being in 10- and 12-year-Old Children from 24 Countries: The Buffering Effect of Family and Teacher Support
No full textBullying victimization in children is a recognized public health concern in many countries worldwide. Specifically, studies have consistently demonstrated that bullying victimization is one of the indicators that most significantly and negatively influences the subjective well-being (SWB) of children. Following this assumption, a study was conducted to examine the impact of bullying victimization on subjective well-being among 75,877 students aged 10 and 12 years across 24 countries. Additionally, the moderating role of support from teachers and family members in the relationship between bullying victimization and subjective well-being was investigated using structural equation modeling (SEM) analysis. The results show that, in many countries, there is an interaction effect of both family support and teacher support figures in both age groups (10 and 12 years). However, significant variability in these interaction effects was observed across countries, and in some countries, no moderating effect was detected. Specifically, in the 12-year-old group, a larger number of countries show no interaction effect from any adult support figure in the relationship between bullying victimization and SWB. The findings are discussed with a focus on the buffering effects of both types of support, the variability observed across countries, and the practical implications of these resultsOpen Access funding provided thanks to the CRUE-CSIC agreement with Springer Nature
Avenços en els fonaments matemàtics de l’anàlisi composicional de dades: convexitat i normes Lp. Aplicació a la regressió lineal LASSO amb covariable composicional
No full textENG- Compositional data are a special type of multivariate data where the variables represent parts of a whole. These data are commonly encountered in fields such as geology, biology, economics, and chemistry, where the proportions between components are more informative than the absolute values. A classic example is the chemical composition of a rock, where the percentages of each element sum to 100%. Another example is the composition of a diet, where the proportions of different nutrients (proteins, carbohydrates, fats, etc.) add up to 100%.
A key aspect of compositional data is that the valuable information lies not in the absolute values of the parts, but in the relative relationships between them. For instance, the relative proportion of one element compared to another may be more significant than their individual values. This relative nature means that traditional statistical methods, if applied directly to compositional data, can lead to misleading or inconsistent conclusions. A common issue is the identification of spurious correlations, which arise from the constant sum constraint inherent in compositional data, rather than reflecting any true relationship between the variables.
To address these challenges, Aitchison geometry is used— a mathematical framework specifically designed for analyzing compositional data. This geometry introduces techniques such as the log-ratio transformation, which maps compositional data into a Euclidean space where conventional statistical methods can be applied in a coherent way. This ensures proper handling of the relative information in the data, preserving its consistency and preventing misinterpretation.
In this thesis, a coherent framework for convex optimization within Aitchison geometry is established by adapting the definitions of convexity and Lp norms to maintain the compositional structure of the data. The methodological section includes a detailed comparison of LASSO regression models with different penalty norms, analyzing how the regularization process affects the subcompositional structure of the linear model.
In summary, this thesis advances the methodological tools available for analyzing compositional data, enhancing their applicability across a range of scientific disciplines, including geology, molecular biology, economics, and chemistryCAT- Les dades composicionals són un tipus especial de dades multivariants en què les variables representen parts d’un tot. Aquestes dades són habituals en disciplines com la geologia, la biologia, l’economia i la química, on les proporcions entre components són més rellevants que els valors absoluts. Un exemple comú és la composició química d’una roca, on els percentatges de cada element químic sumen el 100%. Un altre exemple és la composició d’una dieta, on les proporcions dels diferents nutrients (proteïnes, carbohidrats, greixos, etc.) sumen el 100%.
Un aspecte fonamental de les dades composicionals és que la informació important no resideix en els valors absoluts de les parts, sinó en les relacions relatives entre elles. Per exemple, el valor relatiu del contingut d’un element respecte a un altre pot ser més informatiu que el seu valor individual. Aquesta naturalesa relativa implica que els mètodes estadístics tradicionals poden conduir a conclusions errònies o incoherents si s’apliquen directament a dades composicionals. Un error típic és identificar correlacions espúries que resulten de la suma constant inherent a les dades, i no de cap relació real entre les variables.
Per evitar aquests problemes, s’utilitza la geometria d’Aitchison, un marc matemàtic específicament dissenyat per analitzar dades composicionals. Aquesta geometria introdueix eines com la transformació logquocient, que converteix les dades composicionals en un espai euclidià on es poden aplicar tècniques estadístiques tradicionals de manera coherent. Això permet tractar correctament la informació relativa de les dades, preservant-ne la consistència i evitant errors d’interpretació.
En aquesta tesi s'ha establert un marc coherent per a l'optimització convexa dins de la geometria d'Aitchison, adaptant les definicions de convexitat i de normes Lp per garantir que les tècniques estadístiques respectin l'estructura composicional de les dades. En l’apartat metodològic s'ha realitzat una comparació detallada entre models de regressió LASSO amb diferents normes en el terme de penalització, examinant com el procés de regularització afecta l’estructura subcomposicional del model lineal.
En resum, aquesta tesi contribueix a l'ampliació del conjunt d’eines metodològiques per a l'anàlisi de dades composicionals, millorant la seva aplicabilitat en disciplines científiques diverses com la geologia, biologia molecular, economia i químicaAquesta tesi ha estat finan¸cada mitjan¸cant un contracte predoctoral (FPI) del Ministerio de Ciéncia e Innovación (Ref: PRE2019-090976). També a través dels projectes de recerca: Anàlisi de Dades Composicionals i Espacials. Compositional and Spatial Data Analysis (COSDA) de l’ Agència de Gestió d’Ajuts Universitaris i de Recerca (Ref: 2021SGR01197), Métodos del análisis Composicional de Datos del Ministerio de Ciencia e Innovación (Ref: RTI2018-095518-B-C21) i Generation and Transfer of Compositional Data Analysis Knowledge del Ministerio de Ciencia e Innovación (Ref:PID2021-123833OB-I00)Programa de Doctorat en Tecnologi