Browsing by Issue Date, starting with "2021-12"
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- Ribeiria pholadiformis Sharpe in Ribeiro (Rostroconchia): history of the study, type-locality and unit, and the topotypical collection of the Geological Museum of PortugalPublication . Ribeiro, M.; Nunes, Andreia; Pereira, SofiaABSTRACT: Ribeiria pholadiformis Sharpe in Ribeiro, the type-species of Ribeirioida (Rostroconcha), was erected almost 170 years ago, based on portuguese fossils from the Middle Ordovician of the Buçaco Syncline. In this paper, we review the history of the study of this species and clarify the type-locality and unit for this taxon: the Cácemes Group (Darriwilian) in the Palheiros stream section (Penacova). The reconstitution of Sharpe’s original label led to discover that one of the paralectotypes is the external mould of the lectotype, being this specimen now divided between the Geological Survey Museum, Keyworth (the latter) and the Natural History Museum, London (the former). Furthermore, we report an unpublished collection of 25 specimens of topotypic material, gathered during the 19th century under the guidance of Nery Delgado, deposited in the Geological Museum of Portugal. Its study will allow assessing the morphological variability of the species for the first time.
- Green approach for the valorization of microalgae Tetradesmus obliquusPublication . Gouveia, Luisa; Jazic, Jelena Molnar; Ferreira, Alice; Maletic, Snezana; Cvetkovic, Dragoljub; Vidovic, Senka; Vladic, JelenaABSTRACT: The main goal of this study was to develop an efficient, green approach for the valorization of Tetradesmus obliquus biomass, with zero waste. This microalga was selected because it is widespread, resistant, easy for cultivation, and fast-growing. In the first step, supercritical carbon dioxide (ScCO2) extraction followed by rapid gas decompression was used for the extraction of biomass. The following step was to apply ultrasound-assisted (UA), microwave-assisted (MA), and subcritical water (SW) extraction on the ScCO2-treated biomass to determine the most efficient processing technology. SW demonstrated to be a superior technique over MW and UA with regard to extraction yield and antioxidant content. Moreover, the chemical and microbiological profiles of SW extracts were determined to evaluate their potential and safety. In addition, to create a procedure with zero waste, the solid waste after SW extraction (residue) was analyzed. The organic profile of extracts and residues contained compounds that belong to groups of aliphatic saturated hydrocarbons, aliphatic unsaturated hydrocarbons, alkylated hydrocarbons, ketones, phenols, and esters. Furthermore, these compounds can be applied in different industries including the pharmaceutical and cosmetic industries. Additionally, the content of metals in residues indicated that this material can be used as animal feed and in agriculture. Finally, a complete reduction of microorganisms present in the initial biomass was obtained for the extracts and residues, indicating their safety.
- Un excepcional registro paleoicnológico de artiodáctilos en el Oligoceno inferior de Abiego (Huesca, España)Publication . Linares Montes, Martín; Canudo, José Ignacio; Luzón, Aránzazu; Castanera, DiegoRESUMEN: El yacimiento de Fondota en Abiego (Huesca, España) es uno de los yacimientos de icnitas de mamíferos más relevantes en el Paleógeno europeo por presentar un número excepcional (más de 600 icnitas) de artiodáctilo. Se localiza en la Cuenca del Ebro, en la base de la Formación Peraltilla (Oligoceno inferior) en un nivel de calizas lacustres. Las icnitas poseen una gran variabilidad en sus morfologías y grado de conservación, sin embargo en la mayoría se observa la impresión de dos dedos en posición anterior, siendo este carácter típico de mamíferos artiodáctilos. Se han identificado cuatro morfotipos: dos se relacionan con el icnogénero Anoplotheriipus; un tercero con Entelondontipus cf. viai; y el cuarto son icnitas indeterminadas de gran tamaño. El yacimiento posee además 32 rastros del icnogénero Anoplotheriipus, que han permitido determinar un posible comportamiento gregario de sus productores.
- Assinatura Geoquímica das Metantracites da Bacia Carbonífera do Douro: Efeitos Geológicos e Influências AmbientaisPublication . Costa, Mariana Isabel Macedo da; Flores, Deolinda; Jesus, A. Pinto deRESUMO: Este trabalho teve como objetivo estudar a geoquímica inorgânica dos carvões da Bacia Carbonífera do Douro (BCD), como contributo para o conhecimento da génese e história geológica desta bacia. Para tal foram estudadas 24 amostras de carvão do Setor de São Pedro da Cova e, do Setor do Pejão, 18 amostras de carvão e 9 de brecha de base. Estas amostras foram sujeitas a estudos petrográficos, geoquímicos, tanto orgânicos como inorgânicos, e mineralógicos. Os resultados demonstraram que estes carvões são classificados como antracite A, à exceção de 6 amostras do Setor do Pejão, que são identificadas como rochas carbonosas (rendimentos em cinzas superiores a 50%), segundo a norma ISO 11760, 2005, e o componente orgânico mais abundante é a vitrinite, mais concretamente a telovitrinite, em ambos os setores. A maioria dos elementos tem afinidade inorgânica com associação aos aluminossilicatos e aos sulfuretos. O sulfureto mais comum é a pirite, tendo-se identificado também galena, blenda e calcopirite. Quanto ao cinábrio, com enorme presença em todas as amostras do Setor de São Pedro da Cova, foi apenas identificado numa amostra no Setor do Pejão. O filossilicato mais comum é a moscovite em ambos os setores, sendo que no Setor de São Pedro da Cova também foi identificada a ilite, e no Setor do Pejão a vermiculite, caulinite e também a biotite. Nestas amostras foram identificados fosfatos, nomeadamente a fluorapatite, o mais comum, o xenótimo e também a monazite, sendo que no Setor do Pejão foi identificada a cheralite, uma monazite de Th. A gorceixite (fosfato com alumínio) foi apenas identificada no Setor de São Pedro da Cova, um importante indicador da ocorrência de circulação de fluidos magmáticos entre a UTS B1 e a UTS D1. A distribuição das concentrações dos elementos de terras raras (ETR) apresentam-se heterogéneas nas quatro camadas de carvão do Setor de São Pedro da Cova, mais um indicador de circulação de fluidos magmáticos nestas camadas. O mesmo não acontece quando comparados os padrões de distribuição da Bacia Oriental, uma escama tectónica do Setor de São Pedro da Cova, bem como com as camadas de carvão pertencentes ao Setor do Pejão, estes apresentam-se muito menos enriquecidos e mais homogéneos.
- Microalgal systems for wastewater treatment: technological trends and challenges towards waste recoveryPublication . Morais, Etiele G.; Cristofoli, Nathana L.; Maia, Inês B.; Magina, Tânia; Cerqueira, Paulo R.; Teixeira, Margarida Ribau; Varela, João; Barreira, Luísa; Gouveia, LuisaABSTRACT: Wastewater (WW) treatment using microalgae has become a growing trend due the economic and environmental benefits of the process. As microalgae need CO2, nitrogen, and phosphorus to grow, they remove these potential pollutants from wastewaters, making them able to replace energetically expensive treatment steps in conventional WW treatment. Unlike traditional sludge, biomass can be used to produce biofuels, biofertilizers, high value chemicals, and even next-generation growth media for “organically” grown microalgal biomass targeting zero-waste policies and contributing to a more sustainable circular bioeconomy. The main challenge in this technology is the techno-economic feasibility of the system. Alternatives such as the isolation of novel strains, the use of native consortia, and the design of new bioreactors have been studied to overcome this and aid the scale-up of microalgal systems. This review focuses on the treatment of urban, industrial, and agricultural wastewaters by microalgae and their ability to not only remove, but also promote the reuse, of those pollutants. Opportunities and future prospects are discussed, including the upgrading of the produced biomass into valuable compounds, mainly biofuels
- Palaeontological content and palaeodepositional interpretation of the Upper Jurassic Alcobaça Formation at Gralha beach (São Martinho do Porto, Portugal)Publication . Barros, Diogo; Pimentel, N.; Magalhães, AntonioABSTRACT: This work aims to carry out a paleontological description of an outcropping Upper Jurassic 65 meters thick sedimentary succession at Gralha Beach, North of São Martinho do Porto in the Lusitanian Basin, that includes mainly reddish to yellowish fine-grained siliciclastics and some interbedded marly layers belonging to the Alcobaça Formation. Detailed facies classification and palaeontological analysis (Micropalaeontology and Ichnology), integrated with Petrography, Calcimetry and X-Ray Diffraction, showed a high-frequency cyclicity and pointed to a deposition in low to very - low energy shallow marine conditions, in a gently dipping, oligotrophic open lagoon linked to a muddy coastal wetland area. This is corroborated by the characteristics of microfossils (calcareous nannofossils, Foraminifera, Ostracoda and Charophyta), Bivalvia, Gastropoda and Echinoderma fragments, Thalassinoides, Ophiomorpha and Rhizocorallium.
- Investigação, Inspeções e ensaios de durabilidade de materiais e revestimentos [Comunicação oral]Publication . Cunha Diamantino, Teresa
- Wine Spoilage Control: Impact of Saccharomycin on Brettanomyces bruxellensis and Its Conjugated Effect with Sulfur DioxidePublication . Branco, Patricia; Coutinho, Rute; Malfeito-Ferreira, Manuel; Prista, Catarina; Albergaria, HelenaABSTRACT: The yeast Brettanomyces bruxellensis is one of the most dangerous wine contaminants due to the production of phenolic off-flavors such as 4-ethylphenol. This microbial hazard is regularly tackled by addition of sulfur dioxide (SO2). Nevertheless, B. bruxellensis is frequently found at low levels (ca 10(3) cells/mL) in finished wines. Besides, consumers health concerns regarding the use of sulfur dioxide encouraged the search for alternative biocontrol measures. Recently, we found that Saccharomyces cerevisiae secretes a natural biocide (saccharomycin) that inhibits the growth of different B. bruxellensis strains during alcoholic fermentation. Here we investigated the ability of S. cerevisiae CCMI 885 to prevent B. bruxellensis ISA 2211 growth and 4-ethylphenol production in synthetic and true grape must fermentations. Results showed that B. bruxellensis growth and 4-ethylphenol production was significantly inhibited in both media, although the effect was more pronounced in synthetic grape must. The natural biocide was added to a simulated wine inoculated with 5 x 10(2) cells/mL of B. bruxellensis, which led to loss of culturability and viability (100% dead cells at day-12). The conjugated effect of saccharomycin with SO2 was evaluated in simulated wines at 10, 12, 13 and 14% (v/v) ethanol. Results showed that B. bruxellensis proliferation in wines at 13 and 14% (v/v) ethanol was completely prevented by addition of 1.0 mg/mL of saccharomycin with 25 mg/L of SO2, thus allowing to significantly reduce the SO2 levels commonly used in wines (150-200 mg/L).
- Critical raw materials deposits map of mainland Portugal: new mineral intelligence in cartographic formPublication . de Oliveira, Daniel Pipa Soares; Filipe, Augusto; Gonçalves, Pedro; Santos, Sara; Albardeiro, LuísABSTRACT: Reliable and unhindered access to raw materials is a growing concern within the EU and across the globe and the demand for Critical Raw Materials (CRM) plays a crucial economic role in most developed countries around the world. These are of extreme importance for supply chains regarding new technologies, sustainability issues and carbon footprint reduction. The definition of a continuously updated list of CRM by the European Commission led to the first CRM Map of Europe in 2016. Following this, several countries have been surveying, preparing, and evaluating their mineral occurrences to create a resources/deposits database and, therefore, to create a CRM map of their own. With this purpose in mind, we present and explain the first Critical Raw Materials Deposits Map of mainland Portugal, at 1:700,000 scale. This paper describes the scientific, technical, and graphical methodologies involved in its design.
- Quistos de dinoflagelados do Cenomaniano médio da Nazaré. Paleoambientes e implicações biostratigráficasPublication . Fernandes, L. B.; Bonito, A.; Castro, Ligia; Alves, Maria Isabel C.; Callapez, Pedro M.RESUMO: No registo estratigráfico das séries pós-rifte do Cretácico Superior de Portugal destaca-se a Plataforma Carbonatada Ocidental Portuguesa, extenso corpo marinho do Albiano médio ao Turoniano inferior, contemporâneo de máximos eustáticos e inundação generalizada das margens continentais europeias e norte-africanas do Mar de Tétis. Considerado um dos seus principais afloramentos, o promontório da Nazaré expõe uma sucessão carbonatada com abundante conteúdo fóssil. Em particular, as suas fácies lagunares do Cenomaniano médio, ricas em matéria orgânica, constituem um local de excelência para o estudo de quistos de dinoflagelados (ou dinoquistos). Os estudos palinológicos efetuados nestas fácies demonstraram a presença de associações diversas de dinoquistos (Subtilisphaera sp., Xenascus sp., grupo Sentusidinium e Florentinia sp.), identificando taxa inéditos para o Cretácico português, acrescentando novos dados biostratigráficos e paleoambientais. As associações sugerem a existência de ambiente margino-lagunar, ligado ao desenvolvimento de uma plataforma carbonatada interna e afetado por acarreio detrítico fino proveniente de drenagem fluvial.