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- Portuguese historical palaeobotanical collections reveal a new species of late Palaeozoic marattialean fernPublication . Correia, Pedro; Šimunek, Zbynek; Pereira, ZéliaABSTRACT: A new Late Pennsylvanian marattialean species, Cyathocarpus felicianoi sp. nov., is described and illustrated from the Douro Carboniferous Basin, northwestern Portugal, from Stephanian C (upper Gzhelian, Upper Pennsylvanian) deposits. The studied fossil material is composed of penultimate and ultimate sterile ‘pecopterid’ frond fragments preserved as adpressions and belongs to the Carlos Teixeira's collection, an invaluable palaeobotanical collection from the Portuguese geological surveys. The description of this new fern fossil-species based on historical palaeobotanical collections, highlights the importance of natural history collections for the advancement of science, especially regarding the knowledge about diversity and richness of marattialean ferns of Euramerican Carboniferous.
- The palynology of the Upper Triassic-Lower Jurassic in the Algarve and Lusitanian basins, PortugalPublication . Vilas Boas, Margarida; Cirilli, Simonetta; Pereira, Zélia; Duarte, Luis; Fernandes, PauloABSTRACT: High-resolution palynological analyses from the Algarve and Lusitanian basins (Portugal) provide a refined biostratigraphical framework and palaeoenvironmental reconstruction for the Late Triassic-Early Jurassic transition. In the Algarve Basin, three new palynozones (AT, SC, and CP) characterise the Silves Group from the early Carnian to early Hettangian, documenting the first Iberian occurrence of Tulesporites briscoensis and precisely delineating the Triassic-Jurassic Boundary (TJB). In the Lusitanian Basin, three palynozones (CG, IK, and Pm) constrain the Conraria and Pereiros formations to the Norian-Hettangian, with the TJB located at the base of the Pereiros Formation. Palaeoenvironmental reconstructions reveal distinct basin-specific evolutions. The Algarve Basin records an early transition from fluvial (Silves Sandstones) to marginal-marine (lagoonal and pond) settings, evidenced by abundant upper Carnian algal elements and reworked Neoproterozoic algae. Conversely, the Lusitanian Basin reflects a Norian-Hettangian marginal-marine, river-dominated setting, with microforaminiferal linings at the base of the Pereiros Formation marking the earliest marine transgression in the Lusitanian Basin. Quantitatively, both basins show a persistent dominance of xerophytic taxa, indicating a shift toward warmer, seasonally dry conditions across the TJB. Malformed sporomorphs in both records suggest environmental stress potentially linked to Central Atlantic Magmatic Province (CAMP) activity. Comparative analysis reveals that sedimentation initiated earlier in the Algarve (early Carnian) than in the Lusitanian Basin (Norian), suggesting diachronous development during Pangaea breakup. The assemblages show strong affinities with the Onslow Microflora, highlighting the Portuguese margin as a key archive for western Tethyan floral and climatic evolution.
- O arquivo histórico da coleção de lâminas do LNEG de valor científico nacional - LAMINOTECA 1.0Publication . 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, Maria Luísa; Carvalho, Cristina Isabel Paulo; Dias, RubenRESUMO: O arquivo histórico do Laboratório Nacional de Energia e Geologia (LNEG) constitui um acervo científico com quase 180 anos de atividade geológica e mineira, representando um banco de dados excecional e um repositório geológico nacional. Entre as áreas de missão do LNEG destaca-se a preservação, tratamento e disponibilização deste património único. Esta coleção é considerada património científico nacional, com relevância histórica e importância fundamental para a investigação estratégica do país, além de possuir elevado valor económico. Contudo, torna-se necessário que as coleções existentes sejam devidamente organizadas e disponibilizadas online através da plataforma GEOPORTAL do LNEG. Para alcançar este objetivo é, pois, necessário criar e desenvolver um centro de dados digital que facilite e promova a consulta da informação existente. Uma das coleções que requer organização urgente é a coleção de lâminas delgadas e superfícies polidas, composta por milhares de espécimes conservados no LNEG. Esta coleção resulta de inúmeros estudos petrográficos realizados ao longo de décadas sobre rochas, minérios e fósseis, abrangendo o território nacional e os antigos territórios ultramarinos (atualmente países da CPLP). As lâminas delgadas e superfícies polidas são fundamentais para a caracterização das rochas, constituindo um valioso suporte para diversas áreas da missão científica.
- The historical archive of LNEG slides collection of national scientific value - LAMINOTECA 1.0Publication . 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, Maria Luísa; Carvalho, Cristina Isabel Paulo; Dias, RubenABSTRACT: The historical archive of the Laboratório Nacional de Energia e Geologia (LNEG) encompasses nearly 180 years of geological and mining activity, constituting an exceptional scientific repository and a national geological treasure. Among LNEG’s core missions is the preservation, processing, and dissemination of this unique heritage. The collection is recognised as part of the national scientific heritage, holding both historical and strategic importance for research and possessing considerable economic value. However, the existing collections must be properly organized and digitized to ensure their online accessibility through the LNEG GEOPORTAL platform. Achieving this goal requires the creation and development of a digital data centre that will facilitate and promote the consultation of the existing information. One of the archives in greatest need of urgent organization is the collection of rock thin sections and polished surfaces, which includes thousands of specimens preserved at LNEG. These materials are the result of decades of petrographic studies of rocks, fossils, and ores conducted across Portugal and its former overseas territories (now CPLP countries). The slides and polished surfaces are essential for rock characterisation, and their petrographic analysis provides invaluable support across multiple LNEG mission areas.
- A two-stage cultivation strategy for the industrial production of the novel microalga Chlorococcum amblystomatisPublication . Correia, Nádia; Trovão, Mafalda; Santo, Gonçalo E.; Guerra, Inês; Cunha, P.; Fonseca, Joana; Pereira, Hugo; Costa, Monya M.; Ferreira, Sara; Santos, Tamára; Barros, Ana; Cardoso, Helena; Silva, Joana; Gouveia, Luisa; Varela, JoãoABSTRACT: This study presented the industrial-scale validation of a two-stage growth strategy for a poorly explored yet industrially relevant chlorophyte microalga, Chlorococcum amblystomatis, addressing the gap between laboratory research and practical application. By using cultures grown heterotrophically as inoculum for industrial-scale photoautotrophic reactors, this approach significantly accelerated scale-up. The proposed strategy reduced the overall scale-up time by approximately 5.5-fold compared to the conventional pipeline, without compromising productivity or biochemical quality. A maximum biomass concentration of 70.96 +/- 0.35 g L-1 was achieved in 7-L benchtop fermenters under heterotrophic conditions, representing the highest value reported to date for this microalga. The biomass obtained presented a protein content of 32.42 +/- 2.30% of dry weight, which increased to 54.55 +/- 2.04% upon cultivation under photoautotrophic conditions, as well as polyunsaturated fatty acids, which increased from 50.12 +/- 3.27 to 67.74 +/- 0.35% of total fatty acids, with alpha-linolenic acid as the predominant fatty acid. Conversely, the saturated fatty acids content (38.26 +/- 1.63% of TFA) decreased to 22.37 +/- 0.02% of TFA in the phototrophic stage. Pigment contents also increased significantly during the phototrophic stage, with chlorophylls rising from 10.04 +/- 1.68 to 44.91 +/- 5.11 mg g(-)1 and carotenoids reaching notable concentrations, including lutein (5.34 +/- 0.10 mg g-1), beta-carotene (5.92 +/- 0.39 mg g-1), and neoxanthin (3.53 +/- 0.75 mg g-1). Among the industrial photoautotrophic systems tested, the closed tubular photobioreactors were the most suitable configuration for C. amblystomatis cultivation, achieving higher biomass productivity, enhanced protein content and pigment accumulation compared to open raceway ponds. Overall, this work demonstrates a scalable, efficient, and time-saving cultivation strategy for C. amblystomatis, supporting its potential for industrial biotechnological applications.
- Acid-Based Deep Eutectic Solvents for Structural Modification of Sulphite Pulp Cellulose: A Potential Route Toward Advanced MaterialsPublication . Moran, Guadalupe; Costa Trigo, Iván; Domínguez, José Manuel; Vilaseca, FabiolaABSTRACT: The transition toward renewable and environmentally responsible materials has intensified interest in cellulose-based systems for use in sustainable packaging applications. Although cellulose offers biocompatibility, structural versatility, and tuneable physicochemical properties, conventional modification routes rely on harsh chemicals and generate environmentally burdensome effluents. In this study, an efficient and a potentially green strategy for cellulose modification was developed using acid-based deep eutectic solvents (DES) composed of choline chloride and lactic, acetic, or citric acid at different molar ratios. Under mild conditions (110 degrees C, 4 h), DES pretreatment reduced glucan content in sulphite pulp from 99% to 79-93%, depending on the hydrogen bond donor (HBD), while suggesting an apparent increase in relative crystallinity, from approximately 82% to 90%, as estimated by the Segal method. FTIR, XRD, and morphological analyses revealed the disruption of the hydrogen bonding network, enhanced fibrillation, and residual DES-derived functional groups detectable by FTIR. Although DES pretreatment increased structural order, it also reduced enzymatic digestibility due to the higher proportion of crystalline domains. Overall, the results demonstrate that acidic DES constitutes a sustainable and recyclable medium capable of modulating cellulose structure and generating materials with enhanced physicochemical properties. These findings suggest that DES-modified cellulose could serve as a potential reinforcement platform for future biodegradable packaging and bioplastic formulations, enabling the development of high-performance, renewable, and environmentally compliant packaging materials.
- Cyclopentadienyl vs indenyl control of thermal/photoactivated CO release in cationic molybdenum(II) dicarbonyl-ethylenediamine complexesPublication . Bruno, Sofia M.; Calhau, Isabel B.; Dias, Tiago M.; Santos, Adriana; Silva, Luis Cunha; Nolasco, Mariela M.; Goncalves, Isabel S.; Pillinger, MartynABSTRACT: Molybdenum half-sandwich carbonyl complexes continue to attract attention as potential anticancer agents and prodrugs for therapeutic use of carbon monoxide. Building on the known bioactivity and hydrolytic stability of cyclopentadienyl-based Mo fragments, we report the synthesis, structural characterization, and solution behavior of two cationic half-sandwich complexes, [(eta 5-Cp)Mo(CO)2(en)][BF4] (3) and [(eta 5-Ind)Mo(CO)2(en)][BF4] (4) (Cp = cyclopentadienyl, Ind = indenyl, en = ethylenediamine). Complex 3 is described here for the first time, while 4 was structurally characterized by single-crystal X-ray diffraction, revealing a distorted square-pyramidal geometry with cis-CO ligands and a chelating en ligand positioned beneath the indenyl ring. Both compounds are air-stable in the solid state and exhibit enhanced solubility in polar media due to their ionic nature. UV-vis stability studies under simulated physiological conditions (PBS, pH 7.4, 37 degrees C) show gradual decomposition of both complexes, accelerated by visible-light irradiation and/or the presence of air. CO-release behavior was quantified using the myoglobin assay: the allyl precursors [(eta 5-Cp')Mo(eta 3-C3H5)(CO)2] were inert, whereas complexes 3 and 4 released CO slowly, with 4 exhibiting significantly faster thermal CO liberation (t1/2 approximate to 129 min; 0.74 equiv. CO after 6 h). Complex 3 showed minimal thermal CO release but underwent enhanced and sustained photodecarbonylation under visible-light irradiation, enabling controlled CO delivery. These results identify 3 and 4 as rare examples of Mo-based CO-releasing molecules capable of slow, tunable CO release under biologically relevant conditions, with 3 displaying light-responsive behavior and 4 functioning as a spontaneous thermal CO donor.
- (CrVW)(1-x)(TaTi)x, (x=10 and 20 at.%), high entropy alloys as thermal barriers for nuclear fusion reactorsPublication . Martins, Ricardo; Lara, S. de; Neves, Filipe; Sá, Ana; Luz, Paulo P. da; Pereira Gonçalves, Antonio; Galatanu, Andrei; Sobieraj, Damian; Nguyen-Manh, D.; Dias, MartaABSTRACT: Due to the extreme operating temperatures in nuclear fusion reactors, current divertor monoblock materials, tungsten (plasma-facing material) and CuCrZr (heat sink), exhibit a substantial mismatch in mechanical and thermal properties. Therefore, a thermal barrier interlayer is required to guarantee continuous operation. In this work, (CrVW)(1-x)(TaTi)x alloys (x = 10 and 20 at.%) were studied for application as interlayers in nuclear fusion reactors. Atomistic modeling using Monte Carlo simulations combined with a first-principles-based Cluster Expansion Hamiltonian has been performed as a function of temperature to predict the order-disorder transitions in the investigated high-entropy alloys. Moreover, the experimental alloys were prepared by mechanical alloying followed by spark plasma sintering. Both alloy compositions display strong negative average chemical shortrange ordering below 1500 K for the W-Ta and W-Ti chemical pairs, with an estimated transition temperature around 1300 K. Atomic structures obtained from Monte Carlo simulations for (CrWV)80(TaTi)20 indicate that the ordering observed in this composition is stronger than that for (CrWV)90(TaTi)10. Moreover, both systems exhibit a bcc structure, and heat treated samples show phase growth and a four phase microstructure. The thermal diffusivity increases with temperature, reaching lower values than those of pure W and CuCrZr.