Repositori Obert UdL

The institutional repository collects, manages, disseminates and preserves publications in open access derived from the academic and research activity of the University of Lleida.

 

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Open Access
Linear epitopes of PRRSV-1 envelope proteins ectodomains are not correlated with broad neutralization
(BMC, 2024) Castillo Perez, Jaime; Martínez Lobo, Francisco Javier; Frómeta, Raquel; Castro, Jose Maria; Simarro, Isabel; Prieto, Cinta
Background Neutralizing antibodies against PRRSV are capable of conferring protection against viral reinfection, but they tend to be strain specific and usually have poor cross-reactivity. Nonetheless, it has been described that there are individuals capable of efficiently neutralizing viruses of different origin, so it is expected that there are conserved neutralizing epitopes relevant for broad neutralization. However, although immunodominant regions and neutralizing epitopes have been described in different envelope proteins, their role in broad neutralization is unknown. The main objective of this study was to determine whether the linear epitopes existing in the ectodomains of PRRSV envelope proteins play a role in cross-neutralization. Results A pepscan analysis was carried out using synthetic peptides against the ectodomains of PRRSV envelope proteins and PRRSV-hyperimmune sera of different cross-reactivity. The results obtained confirm the existence of antigenic regions in the ectodomains of the GP2, GP3, GP4 and GP5 that tend to be relatively conserved among different PRRSV isolates. Nonetheless, these antigenic regions have poor immunogenicity since they are only recognized by a limited number of sera. Furthermore, no differences were found between the reactivity of sera with broad cross-neutralization capacity and sera with poor heterologous neutralization activity, which indicate that linear epitopes existing in the ectodomains of PRRSV envelope proteins are not relevant for the development of broadly reactive neutralizing antibodies. Subsequently, some selected peptides were used in competition assays with the virus for binding to the cell receptors and in seroneutralization inhibition assays by incubation with hyperimmune sera. Firstly, some peptides that interfere with virus infectivity were identified in competition assays, but only in the case of one viral isolate, which points to the possible existence of a strain-dependent inhibition. However, the results of the seroneutralization inhibition assay indicate that, under the conditions of our study, none of the peptides used was capable of inhibiting virus neutralization by the hyperimmune sera. Conclusions The results obtained indicate that the linear peptides analyzed in this study do not play a major role in the induction of broadly reactive neutralizing antibodies, which could probably depend on conformational neutralizing.
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Open Access
Effects of Channelling a Peripherally Inserted Central Venous Catheter on Blood Flow
(MDPI, 2024) Hernández-Cabré, Laura; Ulldemolins-Rams, Marta; Vilanova, Judit; Torras, Carles
A catheter is a device that is inserted into the venous system to infuse treatment with controlled doses per unit of time. The study of its interaction with blood flow cannot be easily analysed with common analytical methods or different visualization techniques in real life. Computational Fluid Dynamics has become a very useful tool in a wide variety of fields of scientific study and has allowed access to the understanding of the anatomical and physiological functioning of the human body. In this work, Computational Fluid Dynamics is used to study the effects of inserting a catheter on blood flow and the quality of the mixture of blood with the various substances infused through this device. Results show that the insertion of the catheter not only does not worsen the blood circulation but improves it by reducing stagnant zones. Regarding mixture, a homogenization of the fluids in the venous area before their entrance to the heart was observed. Highest quality mixtures correspond to fewer infused fluids and at lower velocity.
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Open Access
Offline Reinforcement Learning for Adaptive Control in Manufacturing Processes: A Press Hardening Case Study
(American Society of Mechanical Engineers, 2025) Nievas, Nuria; Espinosa-Leal, Leonardo; Pagès Bernaus, Adela; Abio, Albert; Echeverria, Lluís; Bonada, Francesc
This paper explores the application of offline reinforcement learning in batch manufacturing, with a specific focus on press hardening processes. Offline reinforcement learning presents a viable alternative to traditional control and reinforcement learning methods, which often rely on impractical real-world interactions or complex simulations and iterative adjustments to bridge the gap between simulated and real-world environments. We demonstrate how offline reinforcement learning can improve control policies by leveraging existing data, thereby streamlining the training pipeline and reducing reliance on high-fidelity simulators. Our study evaluates the impact of varying data exploration rates by creating five datasets with exploration rates ranging from to ⁠. Using the conservative Q-learning algorithm, we train and assess policies against both a dynamic baseline and a static industry-standard policy. The results indicate that while offline reinforcement learning effectively refines behavior policies and enhances supervised learning methods, its effectiveness is heavily dependent on the quality and exploratory nature of the initial behavior policy.
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Open Access
Productive, Physiological, and Environmental Implications of Reducing Crude Protein Content in Swine Diets: A Review
(MDPI, 2024) Almeida, André M. de; Latorre, Maria Angeles; Álvarez Rodríguez, Javier
Pig production is one of the most important providers of high-quality proteins and amino acids (AAs) to human nutrition. In this sector, feeding has an important economic and environmental impact. A strategy to reduce production costs and negative sustainability effects is reducing dietary crude protein (CP) contents with or without AA supplementation. This review addresses the different aspects related to this strategy, particularly the effects on growth performance and pork traits in piglets and growing and finishing pigs, as well as the physiological molecular mechanisms’ underlying effects. Insight is also provided into the effects of dietary CP reduction on the productive performances of alternative pig production systems and breeding boars and sows. Finally, an overview is conducted on the effects of dietary CP reduction on ammonia, odor, and greenhouse gas emissions arising from pig production systems. Overall, CP reduction may lead to production losses, albeit they can be, to some extent, hindered by adequate AA supplementation. Losses are particularly relevant during the post-weaning phase, whereas in finishing pigs, it may bring additional benefits, such as high intramuscular fat contents in some markets or improved gut barrier function with benefits to the animals’ health and welfare, as well as decreased ammonia emissions to the environment.
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Open Access
Analysis of Sociodemographic and Clinical Characteristics of Inflammatory Bowel Disease in Catalonia Based on SIDIAP
(MDPI, 2024) García-Serrano, Cristina; Mirada Masip, Glòria; Estany, Pepi; Sol, Joaquim; Ortega Bravo, Marta; Artigues i Barberà, Eva María
Background/Objectives: The increasing global prevalence of inflammatory bowel disease (IBD) presents significant challenges to healthcare systems. Our objective was to identify the sociodemographic and clinical characteristics of IBD patients in Catalonia. Methods: A cross-sectional analytical study was carried out on patients diagnosed with IBD in Catalonia (2021). The database of the Information System for the Development of Research in Primary Care of Catalonia was used. Results: In Catalonia, the prevalence of IBD was 474 cases per 100,000 people (pcm), with an average diagnosis age of 42.9 years. Crohn’s disease (CD) represented 34.34% of cases, and 21.2% were smokers and 1% were alcoholics. Nutritional status showed 3% underweight, 36.2% overweight, and 20% obese, with only 0.27% diagnosed as malnutrition. Mental health issues are notable; 36,531 pcm patients were diagnosed with anxiety and 14,656 pcm with depression, and 8.24% had a high risk of mortality measured by the Charlson index. The most prevalent vaccine-preventable infections were influenza (19,356 pcm), herpes zoster (8099 pcm), and varicella zoster (6946 pcm), with 4.56% of patients requiring hospitalisation for one of these reasons and 32.8% of patients for IBD complications, with higher rates observed in cases of CD. Conclusions: The prevalence of IBD was high, especially in urban areas, and patients showed a relevant number of comorbidities. IBD requires a comprehensive evaluation and interdisciplinary management to improve disease control.