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- Microalgae-associated Stenotrophomonas maltophilia enhances lutein production and biostimulant activity in Monoraphidium spPublication . Manoel, João; Štěrbová, Karolína; Saini, Mohit Kumar; Barcenas-Perez, Daniela; Cheel, José; Grivalsky, Tomás; Lakatos, Gergely Erno; Lukes, Martin; Urajová, Petra; Ferreira, Alice; Figueiredo, Daniel; Gouveia, Luisa; Masojidek, Jiri; Saurav, KumarABSTRACT: Photosynthetic organisms like microalgae can collect solar energy and transform it into biochemical compounds as other forms of energy that can be utilized in metabolic processes. In nature, microalgae coexist with bacterial communities and may maintain a symbiotic relationship. In the current study, a heterotrophic bacterium, Stenotrophomonas maltophilia was isolated from the phycosphere of a cold-adapted green microalga Monoraphidium sp. (further abbreviated as Monoraphidium). By using advanced liquid chromatography-high-resolution tandem mass spectrometry (LC-HRMS/MS), we were able to detect homoserine lactones (HSLs): 3OHC12-HSL, 3OHC10-HSL, 3OHC14-HSL, C10-HSL, C8-HSL, and OC14-HSL, produced by S. maltophilia. Further, the role of this bacterium in establishing intricate relationships and its implication on biotechnological potential was evaluated. Significant improvements were found in the lutein production of the Monoraphidium culture with bacterial supplements, achieving about 19.3 +/- 0.88 mg g-1 DW of this carotenoid compared to 13.7 +/- 1.87 mg g-1 DW in the control, which represents an increase of about 40 %. Furthermore, the biostimulant potential of Monoraphidium was evaluated using the germination tests with tomato and barley seeds. A higher germination index was observed with improvements of 55 % in tomato and 110 % in barley, respectively, as compared to the control culture, which was related to the microalgae's growth stage. The role of the bacterium was evaluated in how the intricate relationships with the microalgal culture can affect its biotechnological potential (e.g., biostimulant activity and lutein production). The current work expands our knowledge towards designing an efficient polyculture based on complementary traits and metabolic potential to maximize the yield and bioactivity in algal biotechnology.
- Evaluating the role of physical mechanisms as possible triggers for turbidity currents in a deep ocean seamountPublication . Lebreiro, Susana M.; Peliz, Álvaro; Antón, Laura; Nave, Silvia; Reguera, M. Isabel; Lozano-Luz, Rocío; Waelbroeck, Claire; Crowhurst, Simon; Martrat, Belen; Lopez, Jordi F.; Hebert, Raphael; Lopez-Rodriguez, AlejandraABSTRACT: Turbidity currents on continental margins are often attributed to cyclic climate variability and sea-level change, while the causes of deep ocean turbidites are as yet to be tested. The Atlantic Iberian margin provides a unique setting to contrast deep ocean and continental environments, including depression features that further protect from resuspension and erosion by along-slope bottom currents. We present records of low-frequency, non-periodic, climate-independent turbidites from three deep cores covering up to 426,000 years in the Tore seamounts area. By evaluating a range of physical oceanographic mechanisms, the breaking of internal waves and mesoscale Mediterranean-eddies against unstable slopes in the seamounts area arises as the most likely triggers that precondition the recurrence pattern of the observed deep ocean turbidites.
- Arquivo de lâminas e superfícies polidas do LNEG, uma coleção de valor científico nacional: LAMINOTECA 1.0 do LNEGPublication . Pereira, Zélia; Quental, Lídia; Jorge, Micael; Teixeira, Rui; Patinha, Pedro; Xavier Matos, João Manuel; Mesquita Soares, Sofia; Silva Mendes, Márcia Cristina; Pereira, Aurete; de Oliveira, Daniel Pipa Soares; Matos, Luísa; Carvalho, Cristina Isabel Paulo; Dias, RubenRESUMO: O arquivo histórico do Laboratório Nacional de Energia e Geologia (LNEG) engloba um espólio científico resultante de quase 180 anos de atividade geológica e mineira, o que constitui um banco de dados excecional e um verdadeiro repositório geológico nacional. No âmbito das áreas de missão do LNEG, consta a preservação, tratamento e disponibilização deste património único. Este espólio é considerado património científico nacional, com significado histórico e fundamental à investigação estratégica do país e de enorme valor económico. Todavia, é pois, necessário que as coleções existentes se encontrem devidamente organizadas e preparadas para serem disponibilizadas online através da plataforma geoPortal da Energia e Geologia (GEG), infraestrutura online do LNEG. E, para a concretizar este objetivo, será necessário criar e desenvolver um centro de dados digital sobre coleções especificas, que facilite e promova a consulta da informação existente. O projeto LAMINOTECA 1.0 visa estabelecer um novo modelo de organização e valorização do espólio histórico do LNEG, parte integrante do repositório geológico nacional. Paralelamente, promove o reforço funcional do GEG, enquanto plataforma digital central institucional e de acesso público, para disponibilização estruturada e georreferenciada das coleções temáticas, com destaque para as geológicas e mineiras. Esta iniciativa facilitará a pesquisa e consulta especializada, contribuindo para o avanço científico, educativo e económico. Espera-se que este projeto apoie, no futuro, atividades de I&D aplicadas às áreas estratégicas do LNEG, nomeadamente o Plano Nacional de Cartografia e o Plano Nacional de Prospeção no âmbito do Ato das Matérias Primas Críticas, reconhecendo o valor económico e territorial do conhecimento geológico e fomentando a especialização inteligente em petrografia, paleontologia e mineralizações.
- Techno-economic analysis of a novel hybrid wind-wave floating platform concept: The OctaPlatPublication . Rodrigues, M.B.V.A.; Portillo, Juan C. C.; Henriques, João; Gato, Luís; Mendonça, Nuno P.ABSTRACT: This work focuses on the techno-economic analysis of a novel floating offshore hybrid wind-wave platform. Floating multi-purpose platforms can potentially reduce costs associated with floating offshore wind. This work is based on the OctaPlat, a barge-type hybrid wind-wave floating platform designed at Instituto Superior Técnico, University of Lisbon. The paper presents the concept and numerical model of the floating wave platform, comprising five oscillating water column (OWC) wave energy converters, which was implemented in the object-oriented non-causal Modelica language. The OctaPlat configuration investigated here was equipped with the 15 MW IEA reference wind turbine, whose power output was computed using OpenFAST©. A sensitivity analysis of the geometry was performed, and the best performer design reached an average annual wave turbine power of 2.5 MW and a total wind-wave power of about 10.75 MW for a selected site off the west coast of Portugal. The levelized cost of energy (LCOE) was determined for a farm in the selected location. Various scenarios were assessed, and a Monte Carlo approach resulted in a probable value of LCOE of 135 €/MWh, with LCOE P90 and LCOE P10 values of 99 and 180 €/MWh, respectively. Experimental tests of the wave energy conversion systems were performed on a scale of 1:100, and comparisons with numerical results showed good agreement, with a coefficient of determination (R 2) of approximately 0.94 and relative differences were less than 20%, except for a few peak deviations. These results reveal the potential competitiveness of wind-wave multi-purpose platforms in floating offshore renewable energy projects.
- Miragaia longicollum MG 4863: New fossil and historical evidence from the most complete stegosaur from EuropePublication . Costa Pinto, Francisco; Maidment, Susannah; Sequero, Cristina; Crespo, Vicente D.ABSTRACT: Additional historical data regarding the original finding and excavation (circa 1958-1959) of the Miragaia longicollum stegosaur MG 4863 has been identified (including field notes and the complete field map), allowing a better understanding of its stratigraphic context. Additionally, osteological material that was previously partially encased in matrix was fully prepared and restored, including anterior and posterior caudal vertebrae, metacarpals, and five semi-complete dorsal vertebrae (the latter being the most significant addition, as these are the only skeletal elements shared by all type specimens of dacentrurine taxa). New anatomical information from these additional elements provides further evidence that M. longicollum is distinct from the closely related Late Jurassic stegosaur Dacentrurus armatus from England (demonstrated mainly by various caudal differences). The newly prepared material further completes what was already the best reference specimen among the Dacentrurinae clade, as well as Stegosauria in Europe during the Late Jurassic, increasing its value to better understand these contexts in future studies.
- Social Awareness as a Catalyst for Biochar Adoption in the Agricultural and Forestry SectorsPublication . Janiszewska-Latterini, Dominika; Ortigueira, Joana; Lopes, Tiago; Gościańska-Łowińska, Julia; Augustyniak-Wysocka, Dobrochna; Leszczyszyn, Ewa; Nobre, CatarinaABSTRACT: Biochar, a carbon-rich material produced from the pyrolysis of organic matter, has garnered attention for its potential agricultural and environmental benefits, including soil improvement, enhanced crop yields and climate change mitigation. Despite its promise, biochar adoption has been hindered by limited social awareness, particularly in industrialised countries. This review explores the factors influencing biochar's acceptance in agriculture and forestry, focusing on the social aspects that affect its integration. A systematic literature review was conducted to identify studies on social awareness and acceptance, revealing significant barriers such as a lack of knowledge among farmers, high production costs and insufficient infrastructure. In industrialised countries, while technical research on biochar has progressed, farmers often remain unfamiliar with its benefits, and resistance to adoption is common. Studies show that social factors such as age, education level and access to funding play a crucial role in biochar adoption. Furthermore, a lack of government incentives and unclear regulatory frameworks exacerbate the challenge. Conversely, studies from lower-income countries suggest that small-scale, cost-effective biochar production systems may hold promise. The review also identifies strategies to enhance biochar's social acceptance, including targeted education programs, financial incentives and clearer regulatory standards. Despite varying levels of social awareness, the literature suggests that with increased outreach, biochar could significantly contribute to sustainable agricultural practices globally. This review underscores the need for further research into the social dimensions of biochar adoption and the implementation of policies to foster its widespread use.
- Determination of reflectance of interest from limited state-of-the-art solar reflector field soiling measurementsPublication . Wette, Johannes; Sutter, Florian; Cunha Diamantino, Teresa; Montecchi, Marco; Bern, Gregor; Fernández-García, AránzazuABSTRACT: In concentrated solar thermal technologies, plant operators usually monitor the soiling of their solar field with handheld reflectometers. These measurements can be used for yield calculations and to adapt cleaning strategies: if the reflectometer reading falls below an empirically established threshold, the solar field should be cleaned. There are several commercial reflectometers available for this purpose, but all of them measure at different combinations of wavelength, acceptance angle or incidence angle. It is the purpose of this study to bring the readings from all main commercial reflectometers to the same representative value, enabling their comparison with one another and the translation of these readings into a meaningful reflectance parameter. Thus, different handheld reflectometers are correlated with a laboratory reflectometer, capable of measuring in the whole solar spectral region, covering a wide range of incidence and acceptance angles. The most significant parameter is the near-specular solar-weighted reflectance, measured at the typical incidence and acceptance angles for a given plant, as it is the most precise parameter to describe the reflected energy from the solar field. The correlations for all included reflectometers, show highly linear correlations over a wide range of soiling levels with low deviations. Consequently, the correlations presented herein enable the plant operators at the studied site to compute the near-specular solar-weighted reflectance from their reflectometer readings. and, with that, increase the significance of the measurements without collecting any additional data. The work also establishes a detailed procedure to derive this type of correlations at any site of interest.
- Optimizing Chlorella vulgaris production and exploring its impact on germination through microalga-N2-fixing bacteria consortiaPublication . Sanchez-Zurano, Ana; Vilaro-Cos, Silvia; Figueiredo, Daniel; Melkonyan, Lusine; Ferreira, Alice; Acien Fernandez, F. Gabriel; Lafarga, Tomás; Gouveia, LuisaABSTRACT: Microalgal biomass is increasingly valued in industrial and agricultural sectors due to its bioactive compounds. However, large-scale production remains costly, mainly due to nitrogen fertilizer expenses. A promising sustainable alternative is co-cultivation with N2-fixing bacteria, capable of supplying biologically available nitrogen. In this study, Chlorella vulgaris was grown in synthetic medium with and without nitrogen, as well as in co-culture with three different N2-fixing bacteria in nitrogen-free medium. Microalgal growth was assessed by dry weight, Fv/Fm ratio, and flow cytometry, which also allowed evaluation of population dynamics and cell viability. Biomass composition (proteins, carbohydrates, lipids, chlorophyll, and carotenoids) was analyzed under all conditions. Co-cultures in nitrogen-free medium showed comparable biomass productivity to nitrogen-supplemented controls, although Fv/Fm values indicated physiological stress in some cases. Moreover, the agricultural potential of the resulting biomass and supernatants was evaluated through germination bioassays using lettuce seeds. All cultures tested at 0.2 g & sdot;L-1 significantly improved the germination index. Also, applying the culture supernatant (biomass removed) also yielded positive effects, with GI increases exceeding 40 %. These results suggest that co-cultivation with N2-fixing bacteria can support efficient microalgal production while generating biomass and supernatants with biostimulant potential, contributing to sustainable agriculture and circular bioeconomy strategies.
- Advancing Sustainable Production of High-Performance Cellulose PulpsPublication . Moran, Guadalupe; Costa Trigo, Iván; Bastida, Gabriela Adriana; Mazega, André; Duran, Josep; Domínguez, José Manuel; Vilaseca, FabiolaABSTRACT: Highlights What are the main findings? Enzymatic hydrolysis pretreatment of industrial pulps Pulp composition influencing the enzymatic performance Enhanced conditions for high-performance cellulose pulps What is the implication of the main finding? Sustainable methodology to produce cellulose pulps Lower environmental impact and alignment with circular economic principles Improvements in tensile strength, air permeability, hydrophobicity, and internal bondingHighlights What are the main findings? Enzymatic hydrolysis pretreatment of industrial pulps Pulp composition influencing the enzymatic performance Enhanced conditions for high-performance cellulose pulps What is the implication of the main finding? Sustainable methodology to produce cellulose pulps Lower environmental impact and alignment with circular economic principles Improvements in tensile strength, air permeability, hydrophobicity, and internal bondingAbstract With a growing demand for renewable resources in high-performance materials, sustainable methods are preferred for their lower environmental impact and alignment with circular economy principles. Among these, enzymatic hydrolysis remains relatively underexplored yet shows strong potential for cellulose fibrillation, offering a promising route that may lower energy requirements by minimizing the need for extensive refining compared to conventional mechanical or chemical approaches. In this study, enzyme cocktails rich in cellulase and xylanase were applied to three industrial pulps, sulphite, bleached Kraft eucalyptus and thermomechanical pine, to produce high-performance cellulose pulps. Treatments were carried out using varying enzyme loads (5-40 filter paper units per gram of dry pulp, FPU/gdp) and reaction times (1-16 h). The resulting chemical composition, structural morphology, and physical-mechanical properties were systematically evaluated. The findings revealed that pulp composition strongly influenced enzymatic treatment, affecting surface fibrillation, fibre aggregation, swelling, and fibre shortening. Under optimized conditions, enzymatic pretreatment significantly enhanced paper performance, with improvements in tensile strength, air permeability, hydrophobicity, and internal bonding. Overall, enzymatic hydrolysis represents a sustainable solution and a strategy which could reduce energy expenditures to high-performance cellulose pulps, suitable as reinforcing fibres in packaging applications.
- Optimized Planning Framework for Radial Distribution Network Considering AC and DC EV Chargers, Uncertain Solar PVDG, and DSTATCOM Using HHOPublication . Bonela, Ramesh; Tripathy, Sasmita; Roy Ghatak, Sriparna; Swain, Sarat Chandra; Lopes, Fernando; Acharjee, ParimalABSTRACT: This study aims to provide an efficient framework for the coordinated integration of AC and DC chargers, intermittent solar Photovoltaic (PV) Distributed Generation (DG) units, and a Distribution Static Compensator (DSTATCOM) across residential, commercial, and industrial zones of a Radial Distribution Network (RDN) considering the benefits of various stakeholders: Electric Vehicle (EV) charging station owners, EV owners, and distribution network operators. The model uses a multi-zone planning method and healthy-bus strategy to allocate Electric Vehicle Charging Stations (EVCSs), Photovoltaic Distributed Generation (PVDG) units, and DSTATCOMs. The proposed framework optimally determines the numbers of EVCSs, PVDG units, and DSTATCOMs using Harris Hawk Optimization, considering the maximization of techno-economic benefits while satisfying all the security constraints. Further, to showcase the benefits from the perspective of EV owners, an EV waiting-time evaluation is performed. The simulation results show that integrating EVCSs (with both AC and DC chargers) with solar PVDG units and DSTATCOMs in the existing RDN improves the voltage profile, reduces power losses, and enhances cost-effectiveness compared to the system with only EVCSs. Furthermore, the zonal division ensures that charging infrastructure is distributed across the network increasing accessibility to the EV users. It is also observed that combining AC and DC chargers across the network provides overall benefits in terms of voltage profile, line loss, and waiting time as compared to a system with only AC or DC chargers. The proposed framework improves EV owners' access and reduces waiting time, while supporting distribution network operators through enhanced grid stability and efficient integration of EV loads, PV generation, and DSTATCOM.