Sapientia
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Establishment of a genetic resource bank for restocking management in Portuguese oyster (Crassostrea angulata) and striped venus clam (Chamelea gallina)
Publication . Anjos, Catarina Miranda Castilho dos; Cabrita, Elsa; Matias, Domitília
Bivalves are essential for fisheries, aquaculture, and ecosystems, serving as nutrient-rich resources for human consumption. Despite their significance, many bivalve resources, including Crassostrea angulata (Portuguese oyster) and Chamelea gallina (striped venus clam) in Europe, evidence signs of depletion due to environmental change, anthropogenic impact, and overexploitation, requiring rehabilitation measures. One possible strategy involves establishing a genetic resource bank via cryopreservation. However, cryopreservation presents challenges, requiring optimization of freezing and thawing conditions, particularly the cryoprotectant solution, and understanding cryodamage. The present thesis aims to explore and establish conditions to store and preserve the genetic resources of C. angulata and C. gallina populations. Chapter 1 provides contextual background, on the current situation of bivalve production and the importance of these resources, with special attention on the endangered and valuable species for aquaculture/fisheries, C. angulata and C. gallina. The chapter addresses the fundamental principles of cryobiology and current knowledge on bivalve cryopreservation methodologies for sperm and larvae. This chapter discusses the value of cryodamage assessment tools, emphasizing “omics” molecular tools for high-potential analysis. Chapters 2 and 3 aim to optimize and develop new cryopreservation protocols for the target species. Chapter 2 investigates the effect of the cryoprotectant supplementation with sugars (trehalose and sucrose) on the post-thaw sperm quality of C. angulata. Several methodologies not commonly used in bivalve cryopreservation works were employed, including the determination of reactive oxygen species levels, acrosome integrity and the activity of antioxidant enzymes (superoxide dismutase - SOD, glutathione reductase - GR and glutathione peroxidase - GPX). Sugars supplementation, especially trehalose reduced lipid peroxidation and ROS levels having a positive effect in plasma membrane and acrosome integrity. Chapter 3 evaluates the larval quality of C. angulata and C. gallina exposed and cryopreserved with cryoprotectant solutions that differ in the permeant agent (dimethyl sulfoxide - DMSO and ethylene glycol - EG). The work aimed to understand the effects of cryoprotectant exposure and, cryopreservation on malformations, movement, and enzymatic activity compared with non-exposed larvae. The methodologies for cryopreserving D-larvae of both species were established for the first time. Chapter 4 investigates C. angulata D-larvae cryodamage during cryoprotectant exposure and cryopreservation, using RNA sequencing. This molecular approach was essential for providing evidence that the freezing process was the critical step rather exposure. Furthermore, identified 11 genes as relevant biomarkers of freezability for D-larvae quality assessment. This thesis presents strategies for cryopreserving the genetic material of C. angulata and C. gallina and for cryodamage evaluation.
Off the shelf: regulation of fish blood pH through ionocyte membrane remodelling and protein translocation without additional synthesi
Publication . Guerreiro da Costa Guerreiro, Pedro Miguel; Canario, Adelino
Ocean acidification (OA), together with warming and deoxygenation, forms the “deadly trio,” a combination that reduces ecosystems’ resilience, makes marine biodiversity vulnerable, and is considered a main contributor to global mass extinctions in the Earth’s history (1).
Enhancing cryopreservation of human induced pluripotent stem cells: bottom‐up versus conventional freezing geometry
Publication . Teodoro Duarte Garcia Morais, Fernando Jorge; El-Guendouz, Soukaina; Neves, Rafaela; Duarte, Andreia; Rodrigues, Miguel A.; Pinho Melo, Eduardo
Induced pluripotent stem cells (iPSCs) hold large potential in regenerative medicine due to their pluripotency and unlimited self-renewal capacity without the ethical issues of embryonic stem cells. To provide quality-controlled iPSCs for clinical therapies, it is essential to develop safe cryopreservation protocols for long-term storage, preferably amenable to scale-up and automation. We have compared the impact of two different freezing geometries (bottom-up and conventional radial freezing) on the viability and differentiation potential of human iPSCs. Our results demonstrate that bottom-up freezing under optimized conditions significantly increases iPSC viability, up to 9% for cell membrane integrity and up to 21% for cell metabolic state, compared to conventional freezing. The improvement achieved for bottom-up versus conventional freezing was maintained after scale-up from cryogenic vials to 30 mL bags, highlighting its potential for clinical applications. These findings show that bottom-up freezing can offer a more controlled and scalable cryopreservation strategy for iPSCs, promoting their application in regenerative medicine.
El final de un camino. Las primeras hoces neolíticas documentadas en yacimientos portugueses
Publication . Gibaja, Juan F.; Cardoso, João Luis; Martins, Filipe; Faustino de Carvalho, António Manuel
Pocas son las evidencias de agricultura vinculadas a las primeras ocupaciones neolíticas de Portugal. De hecho, la escasa conservación de restos carpológicos no ha facilitado conocer la realidad de las prácticas agrícolas en relación con las especies explotadas. En este contexto, han surgido dudas sobre el papel que esta actividad tenía entre las primeras comunidades agricultoras y pastoras. En este artículo hemos abordado el estudio de cinco asentamientos del Neolítico Antiguo con el objetivo de documentar la existencia o no de útiles tallados empleados como hoces. Los resultados confirman el uso de estos instrumentos durante este periodo y su similitud con los hallados en otros yacimientos peninsulares.
Intelligent monitoring systems for electric vehicle charging
Publication . Martins, Jaime; Rodrigues, Joao
Featured Application This paper reviews EV charging challenges and existing monitoring methods to pinpoint key gaps. From our review, we propose a practical monitoring framework that leverages IoT sensors, edge computing, and cloud services for real-time oversight, predictive maintenance, and responsive analysis of user behavior.Abstract The growing adoption of electric vehicles (EVs) presents new challenges for managing parking infrastructure, particularly concerning charging station utilization and user behavior patterns. This review examines the current state-of-the-art in intelligent monitoring systems for EV charging stations in parking facilities. We specifically focus on two key inefficiencies: vehicles occupying charging spots beyond the optimal fast-charging range (80% state-of-charge) and remaining connected even after reaching full capacity (100%). We analyze the theoretical and practical foundations of these systems, summarizing existing research on intelligent monitoring architectures and commercial implementations. Building on this analysis, we also propose a novel monitoring framework that integrates Internet of things (IoT) sensors, edge computing, and cloud services to enable real-time monitoring, predictive maintenance, and adaptive control. This framework addresses both the technical aspects of monitoring systems and the behavioral factors influencing charging station management. Based on a comparative analysis and simulation studies, we propose performance benchmarks and outline critical research directions requiring further experimental validation. The proposed architecture aims to offer a scalable, adaptable, and secure solution for optimizing EV charging infrastructure utilization while addressing key research gaps in the field.