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Decoding a novel non-enzymatic protein acetylation mechanism in sperm that is essential for fertilizing potential
No full textBackground: Protein acetylation has emerged as essential for sperm function, attracting considerable attention recently. Acetylation, typically mediated by lysine acetyltransferases, involves attaching an acetyl group from acetyl-coenzyme A to lysine residues in proteins. Under alkaline conditions, however, acetylation can occur with minimal enzymatic involvement, primarily due to an elevated pH. As sperm migrate towards the ampulla, they experience increasing intracellular pH (pHi) while undergoing two crucial processes for fertilization: capacitation and the acrosome reaction (AR). Whereas the involvement of acetylating enzymes in these events has been partially investigated, the potential for non-enzymatic acetylation driven by the pHi alkalinization remains unknown. Results: This study examined protein acetylation (acLys) levels in sperm incubated under capacitating conditions at pH 7.2 and pH 9.0, the latter condition potentially promoting non-enzymatic acetylation. To more precisely investigate the occurrence of non-enzymatic acetylation events, acetyltransferase activity was selectively attenuated using a specific cocktail of inhibitors. The functional implications of these conditions were assessed by examining key fertilization-related sperm attributes, including motility during capacitation and the ability to initiate the AR. Results demonstrated that alkaline conditions elevated basal acLys levels even with reduced acetyltransferase activity (P < 0.05), indicative of non-enzymatic acetylation. α-tubulin, particularly in the midpiece of the sperm flagellum, was identified as a specific target of this modification, correlating with diminished motility during capacitation. Following the AR, acLys levels in the head and midpiece decreased (P < 0.05) under conditions promoting non-enzymatic acetylation, accompanied by reductions in intracellular and acrosomal pH. In contrast, acLys levels and pH in the sperm head incubated under standard capacitating conditions (pH 7.2) remained stable. Sperm exposed to conditions conducive to non-enzymatic acetylation exhibited an impaired ability to trigger the AR (P < 0.05) compared to those maintained at pH 7.2. Notably, diminished acetylase activity emerged as a key factor impairing the maintenance of intracellular and acrosomal pH levels attained during capacitation, even under a pH of 9.0. Conclusion: This study provides novel evidence for the occurrence of non-enzymatic acetylation in sperm, linked to the modulation of α-tubulin acetylation levels and motility during capacitation. Additionally, it suggests that acetyltransferase activity may play a crucial role in regulating intracellular and acrosomal pH levels in capacitated sperm, facilitating the ARThis study was supported by the Ministry of Science, Innovation and Universities, Spain (grants: PID2020-113320RB-I00 and FJC2021-047682-I), the Regional Government of Catalonia (2021-SGR-0900), and the Catalan Institution for
Research and Advanced Studies (ICREA). Additional funding was provided by the Ministry of Economy and Competitiveness (AGL2013-48421-R
Gestió de l’excel·lència i la qualitat en les escoles de negocis en un entorn disruptiu: un estudi empíric
No full textENG- This doctoral thesis explores the key dimensions that determine the perception of quality in business schools in a global context marked by competition and disruptive changes. Through a systematic literature review and two empirical studies, the BS-QUAL scale is developed, an innovative tool that allows for measuring and managing students’ perceived quality in these institutions.
The research is structured around three main pillars:
1. Identification of factors: Internal domains (teaching, services and facilities, innovation) and external domains (institutional reputation, internationalization) are defined as key influences on student satisfaction.
2. Development of the BS-QUAL scale: This tool provides a reliable framework for school managers to analyze and improve perceived quality.
3. Importance of sustainability in business schools: It examines how sustainability practices affect schools’ reputation and internationalization and how these dimensions influence perceived quality and students’ likelihood to recommend the school in the future.
The results highlight that strategically managing both tangible and intangible factors is essential to ensuring competitiveness and institutional excellence. This thesis offers practical recommendations for business school managers and proposes new research avenues, opening the door to a deeper understanding of how to maximize student satisfaction and loyalty in an increasingly globalized environment.
Ultimately, this work serves as a practical guide that combines academic rigor and real-world applications to strengthen the position of business schools as key agents in developing business leaders and driving economic and social progressCAT- Aquesta tesi doctoral explora les dimensions clau que determinen la percepció de qualitat en les escoles de negocis en un context global marcat per la competència i els canvis disruptius. Mitjançant una revisió sistemàtica de la literatura i dos estudis empírics, es dissenya l’escala BS-QUAL, una eina innovadora que permet mesurar i gestionar la qualitat percebuda pels estudiants d’aquestes institucions.
La investigació s’estructura en tres eixos principals:
1. Identificació de factors: Es defineixen àmbits interns (docència, serveis i instal·lacions, innovació) i externs (reputació institucional, internacionalització) que influeixen en la satisfacció dels estudiants.
2. Desenvolupament de l’escala BS-QUAL: Aquesta eina proporciona una base fiable perquè els gestors d’escoles puguin analitzar i millorar la qualitat percebuda.
3. Importància de la sostenibilitat en les escoles de negocis: S’examina com les pràctiques de sostenibilitat afecten la reputació i la internacionalització de les escoles, i com aquestes dimensions influeixen en la percepció de qualitat i la recomanació futura per part dels estudiants.
Els resultats evidencien que la gestió estratègica tant de factors tangibles com intangibles és essencial per assegurar la competitivitat i l’excel·lència institucional. Aquesta tesi ofereix recomanacions pràctiques per als directius d’escoles de negocis i planteja noves línies de recerca, obrint la porta a una millor comprensió de com maximitzar la satisfacció i la lleialtat dels estudiants en un entorn cada vegada més globalitzat.
En definitiva, aquest treball esdevé una guia pràctica que combina rigor acadèmic i aplicacions reals per reforçar la posició de les escoles de negocis com a agents clau en la formació de líders empresarials i en el desenvolupament econòmic i socialPrograma de Doctorat en Dret, Economia i Empres
Analytical model to predict crack width and spacing of reinforced concrete elements externally strengthened with fiber reinforced polymers
No full textCracking behavior in Reinforced Concrete (RC) elements externally bonded with Fiber Reinforced Polymer (FRP) materials is still not well assessed in the literature. Few experimental data are, indeed, available about crack spacing and crack width in these elements, with reference to strengthening made of both epoxy bonded plates (EBR technique) and FRP bars or strips applied in grooves realized in the concrete cover (near surface mounted, NSM, technique). In general, although narrower crack widths are expected to occur in RC elements strengthened with FRP materials, the verification of serviceability limit states is still necessary to ensure functionality and protection of internal steel reinforcement, also because increased values of serviceability loads can be attained in the strengthened elements. This paper first presents a review of existing crack width and spacing formulations provided in some international codes with reference to RC elements with and without the FRP reinforcement. The reliability of these formulations is assessed by comparison with experimental results of tests on beams and ties extracted from the literature. Then, a cracking model included in the new MC2020 and developed by the authors for RC elements and based on equilibrium of forces is presented and adjusted to the experimental database considering both FRP strengthening techniques (EBR or NSM). The comparisons with the experimental database demonstrate a higher accuracy of the proposed model in comparison with other approaches for predicting crack width and crack spacing in RC elements strengthened with FRP materialOpen Access funding provided thanks to the CRUE-CSIC agreement with Wile
Catalyst-Directed Selectivity in Vinylcarbene Reactions: A Comparative Study of Ag, Rh, and Cu Complexes
No full textA comprehensive mechanistic investigation is conducted to uncover the factors governing the selectivity of Ag, Rh, and Cu catalysts in vinylcarbene-mediated reactions. The study examines the preference for carbenic versus vinylogous C(sp3)H bond insertion, highlighting the critical roles of the electronic and steric properties of transition metal catalysts. Contrary to previous assumptions that the enhanced electrophilic character of the vinylogous position in metal vinyl carbenes is the primary determinant, the findings demonstrate that the stereoelectronic effects of the ligand play a more dominant role. These insights inform the design of catalytic systems with tailored selectivity, advancing predictive catalysis and CH bond functionalizationResearch funding: Ministerio de Ciencia e Innovación. Grant Number: PID2021-127423NB-I00, PID2023-146946NB-I00, PID2023-146849NB-I00/MICIU/ AEI/10.13039/501100011033/FEDER; OASIS Network. Grant Number: RED2022-134074-T and Generalitat de Catalunya. Grant Number: 2021-SGR-623.
Open Access funding provided thanks to the CRUE-CSIC agreement with Wile
Key insights into TEMPO-mediated oxidation of cellulose: influence of starting material
No full textThe present study investigates the intricate relationships between the properties of cellulose nanomaterials (CNMs) and the lignocellulosic feedstocks from which they are derived. The starting pulps, consisting of eucalyptus, pine, hemp, and sisal commercial bleached pulps where characterized, and later subjected to TEMPO-mediated oxidation at several concentrations, followed by mechanical treatment in a high-pressure homogenizer. The resulting CNMs were extensively analyzed to assess carboxyl content, nanofibrillation yield, optical transmittance, and rheological and structural properties through methods including X-ray diffraction, X-ray photoelectron spectroscopy, solid-state 13C nuclear magnetic resonance, and sugar composition analysis post-acidic methanolysis. Despite the consistent processing conditions, the study reveals significant differences in the physicochemical and rheological behaviors of CNMs, strongly linked to the inherent properties of their respective feedstocks. These disparities highlight the pivotal influence of feedstock characteristics on the final attributes of CNMs, while most of the previous works linked these differences either to chemical or structural differences. The findings suggest that optimizing CNM properties for specific applications requires precise control over feedstock selection and processing parameters, underscoring the critical role of material origin in the development and application of advanced nanomaterialsThis research received funding from the Spanish Ministry of Science, Innovation and Universities (ArtInNano, CNS2022-135789), and the University of Girona and Banco Santander (IFUdG2020).
Open Access funding provided thanks to the CRUE-CSIC agreement with Springer Natur
In-plane aromatic metallo-annulenes: bridging annulene and coordination chemistry
No full textXia and coworkers [Xu B, Chen D, et.al. Nature, 2025, 641, p.106-111] have synthesized a novel class of organometallic molecules that has a metal-centered planar annulene framework. These unprecedented compounds have potential applications in electronics, photonics, and catalysis, as well as building blocks in materials scienceOpen access funding provided thanks to the CRUE-CSIC agreement with Springer Natur
Soil functions are shaped by aridity through soil properties and the microbial community structure
No full textIncreasing aridity poses a threat to soil functionality, as it affects the key players -prokaryotes and fungi- responsible for these functions. Studying microbial diversity and functions in soils from different aridity conditions is crucial to understanding potential adaptations and response mechanisms to climate change, which may ultimately affect soil ecosystem multifunctionality. Here, we used a natural humid-to-arid climate gradient to determine: (1) if and how soil functions and microbial communities change across the aridity gradient; and (2) the main drivers of soil function variability along the gradient. We sampled soils (0–10 cm depth) from 12 sites across the Iberian Peninsula and analyzed their prokaryotic and fungal diversity and biomass as well as soil functions (aerobic respiration and extracellular enzyme activities linked to organic carbon, nitrogen and phosphorus degradation), together with soil physicochemical characteristics. Our results showed that increasing aridity resulted in a gradual change in the microbial community structure and a decrease in fungal diversity. However, soil functions did not show clear changes in response to aridity itself. Instead, microbial respiration and enzyme activities depended mainly on the local soil properties (i.e. organic matter quantity and quality, soil texture and pH) rather than on aridity. Overall, results indicated that in long-term climate-adapted soils, microbial functions are primarily driven by soil edaphology with aridity influencing them indirectly by shaping the microbial community composition and the intrinsic soil characteristicsFinancial support was provided by the Spanish State Research Agency (PCI2020-120702-2/ AEI/10.13039/501100011033), the Swiss National Science Foundation (SNF 31BD30_193667), the Innovation Fund Denmark (BiodivClim-76 GRADCATCH), and the Department of Science and Innovation of the Republic of South Africa through the 2019-2020 BiodivERsA joint call for research proposals, under the BiodivClim ERA-Net COFUND programme; and partially supported by the Agency for Management of University and Research Grants from the Government of Catalunya (Grant Number: 2021 FISDU 00297). AMR acknowledges the funding from the AGAUR-ICREA Academia award (Catalan Institution for Research and Advanced Studies, ref. 2024 ICREA 00144).
Open Access funding provided thanks to the CRUE-CSIC agreement with Elsevie
Power-to-Protein: Electro-cultivation of microbial proteins from recycled nitrogen and carbon dioxide
No full textThis review explores microbial proteins (MP) as a sustainable alternative to traditional protein sources, emphasizing the innovative approach of electro-cultivation, which integrates biological and electrochemical systems. MP production offers substantial environmental advantages, including efficient carbon dioxide fixation, nitrogen recycling, and production resilience to climate variability, achieving protein contents of over 80 %. The review examines key metabolic pathways for MP synthesis, with a particular focus on the potential of hydrogen-oxidizing bacteria for converting renewable energy and waste substrates like carbon dioxide and ammonium into high-value protein. Inputs such as renewable electricity, nutrient sources, and bio-waste utilization are analyzed alongside the challenges of scaling water splitting technologies to support microbial growth. Furthermore, the paper reviews downstream processing techniques for producing high-quality MP, evaluates the economic feasibility of MP production (costing approximately 1€ per kg of dry weight), and highlights its significant environmental advantages over conventional agriculture. Regulatory aspects are discussed in the context of evolving frameworks to support the commercialization of MP. In conclusion, this review identifies critical research gaps, including strategies to improve microbiome stability, efficient gas utilization, product acceptance, and shelf-life studies, offering a roadmap for advancing MP electro-cultivation into a scalable and globally relevant solution for sustainable food SystemsThis work was supported by the Catalan Agency for Management of University and Research Grants [Ref. 2021 LLAV 00076). S.P. is a Serra Hunter Fellow (UdG-AG-575) and acknowledges the funding from the ICREA Academia award. LEQUIA has been recognized as “consolidated research group” (Ref. 2021 SGR01352) by the Catalan Agency of Research and Universities.
Open Access funding provided thanks to the CRUE-CSIC agreement with Elsevier21
CCLR-DL: A novel statistics and deep learning hybrid method for feature selection and forecasting healthcare demand
No full textBackground and Objective: Hybrid forecasting methods aim to overcome the limitations of classical statistical approaches and deep learning models. While statistical methods provide interpretability, they often lack predictive power. Conversely, deep learning models achieve high accuracy but act as “black boxes.” This study introduces the Comprehensive Cross-Correlation and Lagged Linear Regression Deep Learning (CCLR-DL) framework, combining statistical and deep learning techniques to enhance both forecasting accuracy and interpretability. Unlike existing hybrid methods that combine statistical filtering with deep learning, CCLR-DL integrates causal statistical selection with neural forecasting, producing interpretable predictors and consistently achieving higher accuracy than models without feature selection or other standard baselines. Methods: The CCLR-DL framework integrates cross-correlation analysis, lagged multiple linear regression, and Granger causality testing with advanced deep learning architectures. This dual-phase approach first identifies causally significant predictors and then fits them into a deep learning model for multivariate time series forecasting. The framework was validated using a real-world dataset of clinical visits and diagnoses from 6.3 million individuals collected over 10 years. Results: In the evaluated setting, the CCLR-DL framework outperformed baseline models, achieving an average Root Mean Square Error (RMSE) improvement of 19.8% over univariate models, 60.1% over no feature selection, and 51.9% over random selection. The causality phase ensured that all selected predictors demonstrated a significant Granger-causal (GC) relationship. Simpler recurrent architectures, particularly bidirectional Long Short-Term Memory units (BiLSTM), yielded the most accurate forecasts by effectively capturing nonlinear temporal dependencies. Conclusions: By addressing the challenges of both prediction accuracy and model transparency, the CCLR-DL framework offers a new approach for high-dimensional, multivariate time series forecasting. In healthcare settings, it may enable decision-makers to anticipate demand shifts with greater reliability, allowing earlier staff scheduling, more efficient resource allocation, and reduced waiting times. In our evaluation, it consistently outperformed baseline strategies, delivering measurable improvements that translate into thousands of patient visits being forecasted more accurately across large populationsThis work was conducted with the support of the Secretary of Universities and Research of the Department of Business and Knowledge at the Generalitat de Catalunya 2021 SGR 01125, and founded by the Industrial Doctorate Plan 2021 DI 106, provided by the Agència de Gestió d’Ajuts Universitaris i de Recerca (AGAUR).
Open Access funding provided thanks to the CRUE-CSIC agreement with Elsevie
A nature-based solution to mitigate the impact of reclaimed water discharge into a river under water scarcity conditions
No full textWater scarcity in Mediterranean regions is a growing concern. Alternatives are necessary to meet the water demand from urban areas and to maintain ecological flows in rivers due to the decreased availability and the poor quality of water that is found during drought events. In these conditions, flow can be sustained through discharges from sewage plants. However, if river dilution factors are low, the discharges can endanger aquatic ecosystems. To mitigate these impacts, tertiary treatments are integrated into wastewater treatment plants to improve effluent quality. In this study, the impact of a wastewater treatment discharge in a river has been evaluated before and after the implementation of a nature-based tertiary treatment under different river dilution conditions. The water quality of the river as well as of the discharged effluent was assessed through the concentration of small-suspended sludge particles (d 100 μm) are also reduced (69.8 %) by sedimentation. (2) A predictive model to assess the impact of the treated wastewater discharge into the river was developed and calibrated. The model considers different percentages of water treated by the tertiary system in water scarcity scenariosThe research has been carried out within the BIODAPH2O project. The BIODAPH2O project has been funded by the European Commission by the LIFE programme (grant agreement No. 101074191). This study has been also funded by the research project ‘An eco-efficient tertiary system for water reuse in agricultural irrigation (BIODAPH)’ funded by the Ministeri de Ciència, Innovació i Universitats - MCIU within the program “NextGenerationEU” (TED2021-132721B-I00 /MCIN/ AEI / 10.13039/501100011033/ and the European Union “NextGenerationEU”/PRTR). The authors are grateful for the support provided by the managers of Sorigué S.A.U., which are in charge of the wastewater treatment plant in the city of Quart. We thank Luca Mills and Júlia Reinal for their support in the field work.
Open Access funding provided thanks to the CRUE-CSIC agreement with Elsevier1