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2024
Gonçalves, Adriana, Raquel Cabrita, Joana Matos, Inês Rodrigues, Tânia Vieira, João Paulo Borges, and Paula I. P. Soares. "Dual-stimuli-responsive poly (vinyl alcohol) nanofibers for localized cancer treatment: Magnetic hyperthermia and drug release studies." (2024): 105492. Abstract
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Vieira, Tânia, Ana Margarida Rebelo, João Paulo Borges, Célia Henriques, and Jorge Carvalho Silva. "Electrospun Polycaprolactone Membranes Expanded with Chitosan Granules for Cell Infiltration." 16.4 (2024): 527. Abstract
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Hammami, Imen, Manuel Pedro Fernandes Graça, Sílvia Rodrigues Gavinho, Suresh Kumar Jakka, João Paulo Borges, Jorge Carvalho Silva, and Luís Cadillon Costa. "Exploring the Impact of Copper Oxide Substitution on Structure, Morphology, Bioactivity, and Electrical Properties of 45S5 Bioglass®." 9.4 (2024): 213. Abstract
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Caseiro, Catarina, Nicholas G. S. McGregor, Victor Diogo Alves, Ana Luísa Carvalho, Maria João Romão, Gideon J. Davies, Carlos M. G. A. Fontes, and Pedro Bule. "Family GH157 enzyme exhibits broad linkage tolerance and a dual endo/exo- β -glucanase activity on β-glucans." (2024): 137402. AbstractWebsite

The structural and chemical diversity of β-glucans is reflected on the variety of essential biological roles tackled by these polysaccharides. This natural heterogeneity requires an elaborate assortment of enzymatic mechanisms to assemble, degrade or modify, as well as to extract their full biotechnological potential. Recent metagenomic efforts have provided an unprecedented growth in potential new biocatalysts, most of which remain unconfirmed or uncharacterized. Here we report the first biochemical and structural characterization of two bacterial β-glucanases from the recently created glycoside hydrolase family 157 (LaGH157 and BcGH157) and investigate their molecular basis for substrate hydrolysis. Structural analysis by X-ray crystallography revealed that GH157 enzymes belong to clan GH-A, possessing a (β/α)8-barrel fold catalytic domain, two β-sandwich accessory domains and two conserved catalytic glutamates residues, with relative positions compatible with a retaining mechanism of hydrolysis. Specificity screening and enzyme kinetics suggest that the enzymes prefer mixed-linkage glucans over β-1,3-glucans. Activity screening showed that both enzymes exhibit pH optimum at 6.5 and temperature optimum for LaGH157 and BcGH157 at 25 °C and 48 °C, respectively. Product analysis with HPAEC-PAD and LC-MS revealed that both enzymes are endo-1,3(4)-β-glucanases, capable of cleaving β-1,3 and β-1,4-linked glucoses, when preceded by a β-1,3 linkage. Moreover, BcGH157 needs a minimum of 4 subsites occupied for hydrolysis to occur, while LaGH157 only requires 3 subsites. Additionally, LaGH157 possesses exohydrolytic activity on β-1,3 and branching β-1,6 linkages. This unusual bifunctional endo-1,3(4)/exo-1,3–1,6 activity constitutes an expansion on our understanding of β-glucan deconstruction, with the potential to inspire future applications.

Gavinho, Sílvia Rodrigues, Imen Hammami, Suresh Kumar Jakka, Sílvia Soreto Teixeira, Jorge Carvalho Silva, João Paulo Borges, and Manuel Pedro Fernandes Graça. "Influence of the Addition of Zinc, Strontium, or Magnesium Oxides to the Bioglass 45S5 Network on Electrical Behavior." 17.2 (2024): 499. Abstract
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Boavida, Nuno, António B. Moniz, Maria Rosário do Jorge, Célia Costa da Cabral, and Marta Candeias 2º Relatório do Projeto Europeu CERP: Trabalho de Campo. Lisboa: CICS.NOVA, 2024. Abstract

Este relatório pretende descrever e analisar o trabalho de campo realizado no âmbito do projeto CERP. O projeto pretende compreender o estado da arte em Portugal da negociação coletiva portuguesa com referências à transição sustentável e justa no setor dos transportes e no setor público.

Boavida, Nuno, Maria Rosário do Jorge, Marta Candeias, António B. Moniz, and Célia Costa da Cabral A contratação coletiva portuguesa com referências à transição sustentável e justa no setor dos transportes e no setor público. Lisboa: CICS.NOVA, 2024. Abstract

Este relatório pretende fazer uma revisão da literatura sobre a negociação coletiva portuguesa com referências à transição sustentável e justa no setor dos transportes e no setor público.
Portugal tem sido dos países que iniciou já o seu caminho de transição e encerrou as centrais a carvão. Mas em países do Leste europeu, por exemplo, existe muita indústria associada à produção de electricidade a partir do carvão, e onde o encerramento levanta sérias questões sociais. Nestes casos, em particular, é necessário um processo gradual que inclua medidas de apoio à formação e reconversão dos trabalhadores envolvidos.

Burigo, André, and Octávio Mateus. "Allosaurus europaeus (Theropoda: Allosauroidea) Revisited and Taxonomy of the Genus." Diversity. 17.1 (2024): 29. Abstractburigo__mateus_2024_diversity-17-00029.pdfWebsite

Allosaurus is one of the most famous theropod dinosaurs, but the validity and relationships between the different species have been confusing and often questioned. Portugal is relevant to the understanding of the genus in light of the discovery of A. europaeus ML415 from the Early Tithonian of Lourinhã and Allosaurus MNHNUL/AND.001 from Andrés. However, the exact classification and validity of these two specimens has always been controversial. The presence of Allosaurus in Portugal is strong evidence for a North America–Europe Late Jurassic dispersal, later supported by other taxa. A detailed cranial description and specimen-based phylogeny were performed and resolved many of the open questions: (1) The diversity of Allosaurus is limited to three named species: A. fragilis, A. europaeus, and A. jimmadseni. (2) Nine autapomorphies were found in A. europaeus, confirming the validity of the species. (3) Phylogenetic analyses place both Portuguese specimens in the genus Allosaurus, based on the following synapomorphies: jugal bone lateral view, relative heights of quadratojugal prongs, the dorsal prong is equal in height, the jugal bone in lateral view shows shallow accessory pneumatization of the antorbital fossa, the palatine pneumatic recess shape is small, and lacrimal horn morphology has a triangular horn. (4) The Andrés specimen is placed with the A. europaeus and they are considered here to be the same species, which is paleo-geographically and biochronologically congruent. (5) A. europaeus and A. jimmadseni are sister taxa and closer to each other than to A. fragilis. The genus is distributed in occurrences from the United States, Germany, and Portugal, and from the Late Kimmeridgian to the Late Tithonian, while the Cenomanian report from Japan is reidentified as Segnosaurus.

Rotatori, Filippo Maria, Mattia Quaranta, Filippo Bertozzo, Tom Hübner, Bruno Camilo, Octávio Mateus, and Miguel Moreno-Azanza. "Hadrosaur-like vascularisation in the dentary of an early diverging iguanodontian dinosaur." Historical Biology. 36.10 (2024): 1979-1984. AbstractWebsite

ABSTRACTVirtual palaeontology is a growing field, leading palaeontologists to better understand the microanatomy of many extinct species. The application of techniques such as CT and μCT-scanning allows the researchers to study micro-anatomical features in a non-invasive way and make inferences on the palaeobiology of animals. Dinosaurs have been extensively studied using these techniques, with particular focus on the microanatomy of the cranium, whereas relatively little is known of other cranial elements, such as the lower jaw. Here, we aim to fill this gap, describing the microanatomy of the specimen ML 768, an isolated dentary belonging to a dryosaurid iguanodontian dinosaur from the Upper Jurassic of Lourinhã Fm. The dentary ML 768 was subjected to μCT-scanning, and subsequently the data were segmented in Avizo and rendered in Blender. We identified functional and replacement teeth, recognising remnants of old replacement cycles. Furthermore, we mapped a rich neurovascular network present in the dentary and compared it with reference literature. We found that the high vascularisation is shared with other cerapodan dinosaurs with high tooth replacement rates, although homoeostasis may have also played a role in the development of this condition. Further evidence is needed to appreciate the macroevolutionary significance of these findings.

Pereira, Duarte, Carmen Morgado, and Fernanda Barbosa NextBlocks: An Interactive Block Programming Platform. ITiCSE 2024. Milan, Italy, 2024. Abstract

Since Seymour Papert's work with the Logo programming language in the 1960s, there has been a prevailing belief in the effectiveness of visual programming environments for teaching programming to children and novices. As these platforms evolved and became more prevalent, using block programming to teach children and beginners became increasingly more common. However, modern block programming platforms like Scratch and Code.org excessively restrict educators by not allowing them to create custom exercises in the platform. They also tend to make programming a solo activity, not allowing for collaboration and cooperation between learners (Scratch is an exception in this regard). Additionally, they are usually located in standalone websites instead of being implemented in locations that students already frequent regularly. Having identified these gaps in the field of block programming environments, this paper proposes NextBlocks, a new block programming platform implemented as a Moodle plugin. This platform enables educators to create custom exercises, emphasizing social perception and collaboration features. It supports features that are uncommon in block programming environments, contributing to a more interactive and engaging learning experience. Furthermore, being integrated into the Moodle Learning Management System makes NextBlocks more easily accessible within the educational framework. As an open-source platform, besides solving current challenges, it can also serve as a foundation for future expansion by the education community. This paper explores some of the unique features of NextBlocks, presents a case study on the platform, and discusses its potential contributions to enhancing programming education for beginners within a collaborative learning environment.

Burigo, André, and Octávio Mateus. "Notes on the type specimens of Allosaurus atrox and A. Ferox (Theropoda, Allosauridae)." Paleolusitana. 2 (2024): 18-20. Abstractaburigo__omateus_v2.pdf

Allosaurus Marsh, 1877 is one of the most iconic theropods of the Late Jurassic of USA and Portugal. However,
since the first description the genus was used as taxonomical wastebasket to which several species were
described. We revisit three type specimens, Allosaurus fragilis YPM 1930, A. atrox YPM 1890 and A. ferox USNM
2315. We interpret the vertebral material of A. atrox and support it as a junior synonym of A. fragilis, and A. ferox
as Allosaurus indet. rather than A. fragilis.

Botelho, M. C., and H. Rocha. "O conhecimento profissional do professor na mobilização de diferentes representações com diferentes tecnologias." Iberian Journal of Information Systems and Technologies. E71 (2024): 486-499.Website
Rocha, H., and A. Babo. "Problem-solving and mathematical competence: a look to the relation during the study of Linear Programming." Thinking Skills and Creativity. 51 (2024): 1-14. AbstractWebsite

This study seeks reflection on the approaches of 11th grade students to Linear Programming problems, discussing the approaches taken at different moments of the teaching process. It aims to analyze:
How is the students’ mathematical competence characterized in relation to problemsolving;
What differences can be identified in the resolutions at different moments of the teaching and learning process.
We adopt a qualitative and interpretative methodology, analyzing the approaches of two pairs of students with different mathematical backgrounds. The analysis is guided by P´olya’s stages of solving a problem and aspects of the understanding of mathematical competence. The results show different approaches to the problems depending on the teaching moment and different competences. The mathematical background impacts the students’ success when they implement routine procedures, however it does not seem to determine the students’ competence to reason about a problem.

Botelho, M. C., and H. Rocha The role of teachers’ knowledge and the use of different technologies in the classroom. MEDA – Mathematics Education at the Digital Age. Bari, Italy: ERME, 2024. Abstract2024_meda_botelho_rocha.pdf

The potential of technology to enhance the learning of mathematics is widely acknowledged. However, realizing this potential requires teachers to possess the knowledge to effectively integrate it into their teaching practices. This study aims to characterize the mathematics teacher's knowledge when using different technologies in teaching and learning. It also aims to study the existence of relationships between the specific domains of the Knowledge for Teaching Mathematics with Technology – KTMT and the integration of graphing calculator and Excel. The methodology adopted is qualitative with an interpretative approach, using a case study of Mathematics teacher in the 11th grade (16-17 years old) with extensive experience in the use of technology. This study shows that different KTMT knowledge is mobilized, according to the technology chosen and the specific characteristics of each of the technologies used influenced the teacher's pedagogical choices.

Coutinho, Mathilda L., João Pedro Veiga, Andreia Ruivo, Teresa Pereira da Silva, Silvia Bottura-Scardina, Maria Margarida R. A. Lima, Carlos Pereira, Ana Carvalho Dias, Luis Dias, Peter Vandenabeele, and José C. Roseiro. "Characterization of Tableware from Fábrica de Loiça de Sacavém—Linking Analytical and Documental Research." Minerals. 14 (2024). AbstractWebsite

Fábrica de Loiça de Sacavém (ca. 1858–1994) was among the first to produce white earthenware in Portugal, becoming one of the country’s leading ceramic manufacturers during the late 19th to early 20th centuries. Research on white earthenware has accompanied the growing interest in post-industrial archaeology but is still poorly explored compared to more ancient ceramic productions. This study focused on the ceramic body, glazes, and colourants of tableware produced by Fábrica de Loiça de Sacavém during the first 50 years of its activity (1859–1910). A multi-analytical approach was selected to investigate the chemical and mineralogical composition of the ceramic body, glaze, and pigments using optical microscopy, variable-pressure scanning electron microscope energy-dispersive X-ray spectroscopy (VP-SEM-EDS), μ-Raman spectroscopy, μ-X-ray Diffraction (μ-XRD), and reflectance spectroscopy (hyperspectral image analysis). The studied tableware was produced with a Ca-poor siliceous–aluminous white earthenware ceramic body covered with transparent alkali lead or lead borosilicate glaze, and most colourants were complex Cr-based pigments. These results are in agreement with the little documental evidence from this period found in the manufacturer’s archives.

Viñas-Ospino, Adriana, Ana Rita Jesus, Alexandre Paiva, Maria J. Esteve, Ana Frígola, Jesús Blesa, and Daniel López-Malo. "Comparison of green solvents for the revalorization of orange by-products: Carotenoid extraction and in vitro antioxidant activity." Food Chemistry. 442 (2024): 138530. AbstractWebsite

Orange peels contain a considerable number of bioactive compounds such as carotenoids, that can be used as ingredients in high-value products. The aim of this study was to compare orange peel extracts obtained with different green solvents (vegetable oils, fatty acids, and deep eutectic solvents (DES)). In addition, the chemical characterization of a new hydrophobic DES formed by octanoic acid and l-proline (C8:Pro) was performed. The extracts were compared in terms of carotenoid extraction, antioxidant activity by three methods, color, and environmental impact. The results confirmed that the mixture of C8:Pro is a DES and showed the highest carotenoid extraction (46.01 µg/g) compared to hexane (39.28 µg/g). The antioxidant activity was also the highest in C8:Pro (2438.8 µM TE/mL). Finally, two assessment models were used to evaluate the greenness and sustainability of the proposed extractions. These results demonstrated the potential use of orange peels in the circular economy and industry.

Ramos, António, Carla Marchão, João Nuno Pacheco, Alejandro Enfedaque, Dario Coronelli, Duarte Faria, Jorge de Brito, Miguel Fernández Ruiz, and Rui Marreiros. "A review of punching behavior of slab–column connections with recycled coarse aggregate concrete." Structural Concrete (2024). AbstractWebsite
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2023
Coelho, Beatriz J., Joana V. Pinto, Jorge Martins, Ana Rovisco, Pedro Barquinha, Elvira Fortunato, Pedro V. Baptista, Rodrigo Martins, and Rui Igreja. "{Parylene C as a Multipurpose Material for Electronics and Microfluidics}." Polymers. 15 (2023): 2277. AbstractWebsite

Poly(p-xylylene) derivatives, widely known as Parylenes, have been considerably adopted by the scientific community for several applications, ranging from simple passive coatings to active device components. Here, we explore the thermal, structural, and electrical properties of Parylene C, and further present a variety of electronic devices featuring this polymer: transistors, capacitors, and digital microfluidic (DMF) devices. We evaluate transistors produced with Parylene C as a dielectric, substrate, and encapsulation layer, either semitransparent or fully transparent. Such transistors exhibit steep transfer curves and subthreshold slopes of 0.26 V/dec, negligible gate leak currents, and fair mobilities. Furthermore, we characterize MIM (metal–insulator–metal) structures with Parylene C as a dielectric and demonstrate the functionality of the polymer deposited in single and double layers under temperature and AC signal stimuli, mimicking the DMF stimuli. Applying temperature generally leads to a decrease in the capacitance of the dielectric layer, whereas applying an AC signal leads to an increase in said capacitance for double-layered Parylene C only. By applying the two stimuli, the capacitance seems to suffer from a balanced influence of both the separated stimuli. Lastly, we demonstrate that DMF devices with double-layered Parylene C allow for faster droplet motion and enable long nucleic acid amplification reactions.

Dias, Inês J. G., Sofia A. Pádua, Eduardo A. Pires, João PMR Borges, Jorge C. Silva, and Carmo M. Lança. "Hydroxyapatite-Barium Titanate Biocoatings Using Room Temperature Coblasting." Crystals 2023, Vol. 13, Page 579. 13 (2023): 579. AbstractWebsite

The use of orthopaedic and dental implants is expanding as a consequence of an ageing population and also due to illness or trauma in younger age groups. The implant must be biocompatible, bioactive and interact favourably with the recipient's bone, as rapid osseointegration is key to success. In this work, Ti-6Al-4V plates were coated using the CoBlastTM technique, with hydroxyapatite (HAp) and HAp/BaTiO3 (barium titanate, BT) non-piezoelectric cubic nanopowders (HAp/cBT) and piezoelectric tetragonal micropowders (HAp/tBT). The addition of BT, a piezoelectric ceramic, is a strategy to accelerate osseointegration by using surface electric charges as cues for cells. For comparison with commercial coatings, plates were coated with HAp using the plasma spray technique. Using XRD and FTIR, both plasma spray and CoBlastTM coatings showed crystalline HAp and no presence of by-products. However, the XRD of the plasma-sprayed coatings revealed the presence of amorphous HAp. The average surface roughness was close to the coatings' thickness (≈5 $μ$m for CoBlastTM and ≈13 $μ$m for plasma spray). Cytotoxicity assays proved that the coatings are biocompatible. Therefore, it can be concluded that for HAp-based coatings, CoBlastTM is a viable alternative to plasma spray, with the advantage of facilitating room temperature addition of other ceramics, like piezoelectric BaTiO3.

Pessanha, Sofia, Alexandre Veiga, Delfim Doutel, Fernanda Silva, João Silva, Patrícia M. Carvalho, Sofia Barbosa, José Paulo Santos, Ana Félix, and Jorge Machado. "Evaluation of the influence of the formalin fixation time on the elemental content of tissues measured with X-ray fluorescence." Spectrochimica Acta Part B: Atomic Spectroscopy. 205 (2023): 106704. AbstractWebsite
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Silva, A., C. Morgado, and F. Barbosa. "EPIK2 QUIZ: AN EXAMPLE OF EFFECTIVE COLLABORATIVE LEARNING ACTIVITY." Proceedings of 17th annual International Technology, Education and Development Conference. Valença 2023.
Boavida, Nuno, Marta Candeias, Débora Freire, and António B. Moniz. "Opções de política tecnológica: a importância da avaliação, transparência e debate democrático." Público (2023). Abstractopcoes_de_politica_tecnologica_opiniao_publico.pdf

Em Portugal, existe uma ausência de formalização da ciência para assuntos políticos em que a procura de aconselhamento é, em grande medida, informal.

Hammami, Imen, Sílvia Rodrigues Gavinho, Suresh Kumar Jakka, Manuel Almeida Valente, Manuel Pedro Fernandes Graça, Ana Sofia Pádua, Jorge Carvalho Silva, Isabel Sá-Nogueira, and João Paulo Borges. "Antibacterial Biomaterial Based on Bioglass Modified with Copper for Implants Coating." 14.7 (2023): 369. Abstract
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Hammami, Imen, Sílvia Rodrigues Gavinho, Ana Sofia Pádua, Isabel Sá-Nogueira, Jorge Carvalho Silva, João Paulo Borges, Manuel Almeida Valente, and Manuel Pedro Fernandes Graça. "Bioactive Glass Modified with Zirconium Incorporation for Dental Implant Applications: Fabrication, Structural, Electrical, and Biological Analysis." 24.13 (2023): 10571. Abstract
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