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2022
Machado, B., L. Antunes, C. Caetano, J. F. Pereira, B. Nunes, P. Patrício, and M. L. Morgado. "The impact of vaccination on the evolution of COVID-19 in Portugal." Mathematical Biosciences and Engeneering. 19 (2022): 936-952.
Fernandes, Alexandra E., Octávio Mateus, Brian Andres, Michael J. Polcyn, Anne S. Schulp, António Olímpio Gonçalves, and Louis L. Jacobs. "Pterosaurs from the Late Cretaceous of Angola." Diversity. 14 (2022). Abstractdiversity-14-00741.pdfWebsite

Here, we describe the first pterosaur remains from Angola, an assemblage of fourteen bones from the Lower Maastrichtian marine deposits of Bentiaba, Namibe Province. One new species is introduced, Epapatelo otyikokolo, gen. et sp. nov., which comprises an articulated partial left humerus and ulna as well as an articulated left ulna and radius (from a second individual). Phylogenetic analysis confirms a non-nyctosaurid pteranodontian attribution for this new taxon and supports a new apomorphy-based clade, Aponyctosauria, which is here defined. Late Cretaceous pteranodontians are rare in Sub-Saharan Africa and throughout the Southern Hemisphere. Preliminary histological analysis also reveals a likely sub-adult age for one of the specimens. This fossil assemblage provides a first glimpse of Angolan pterosaur paleobiodiversity providing further insight into the Gondwanan ecosystems of the Upper Cretaceous.

A. J. Cain, M. Johnson, Kambites Malheiro M. A. "Representations and identities of plactic-like monoids." Journal of Algebra. 606 (2022): 819-850. AbstractWebsite

We exhibit faithful representations of the hypoplactic, stalactic, taiga, sylvester, Baxter and right patience sorting monoids of each finite rank as monoids of upper triangular matrices over any semiring from a large class including the tropical semiring and fields of characteristic 0. By analysing the image of these representations, we show that the variety generated by a single hypoplactic (respectively, stalactic or taiga) monoid of rank at least 2 coincides with the variety generated by the natural numbers together with a fixed finite monoid (respectively, F) and forms a proper subvariety of the variety generated by the plactic monoid of rank 2.

Santos, F. A., C. Caroço, A. Amendola, M. Miniaci, and F. Fraternali. "3D TENSEGRITY BRACES WITH SUPERELASTIC RESPONSE FOR SEISMIC CONTROL." International Journal for Multiscale Computational Engineering. 20 (2022): 53-64. AbstractWebsite
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Centeno, Pedro, Miguel Alexandre, Filipe Neves, Elvira Fortunato, Rodrigo Martins, Hugo Águas, and Manuel J. Mendes. "Copper-Arsenic-Sulfide Thin-Films from Local Raw Materials Deposited via RF Co-Sputtering for Photovoltaics." Nanomaterials. 12 (2022). AbstractWebsite

The inexorable increase of energy demand and the efficiency bottleneck of monocrystalline silicon solar cell technology is promoting the research and development of alternative photovoltaic materials. Copper-arsenic-sulfide (CAS) compounds are still rather unexplored in the literature, yet they have been regarded as promising candidates for use as p-type absorber in solar cells, owing to their broad raw material availability, suitable bandgap and high absorption coefficient. Here, a comprehensive study is presented on the structural and optoelectronic properties of CAS thin-films deposited via radio-frequency magnetron co-sputtering, using a commercial Cu target together with a Cu-As-S target with material obtained from local resources, specifically from mines in the Portuguese region of the Iberian Pyrite Belt. Raman and X-ray diffraction analysis confirm that the use of two targets results in films with pronounced stoichiometry gradients, suggesting a transition from amorphous CAS compounds to crystalline djurleite (Cu31S16), with the increasing proximity to the Cu target. Resistivity values from 4.7 mΩ·cm to 17.4 Ω·cm are obtained, being the lowest resistive films, those with pronounced sub-bandgap free-carrier absorption. The bandgap values range from 2.20 to 2.65 eV, indicating promising application as wide-bandgap semiconductors in third-generation (e.g., multi-junction) photovoltaic devices.

Pereira, João F., Constantino Caetano, Liliana Antunes, Paula Patr{\'ıcio, Maria Lu{\'ısa Morgado, and Baltazar Nunes. "COVID-19 Hospitalisation in Portugal, the first year: Results from hospital discharge data." medRxiv (2022). Abstract
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Azevedo, A. S., J. P. Firmo, J. R. Correia, C. Chastre, H. Biscaia, and N. Franco. "Fire behaviour of CFRP-strengthened RC slabs using different techniques – EBR, NSM and CREatE." Composites Part B: Engineering. 230 (2022). AbstractWebsite

This paper presents an experimental study about the fire behaviour of reinforced concrete (RC) slabs strengthened with carbon fibre reinforced polymer (CFRP) strips, applied according to three different techniques: externally bonded reinforcement (EBR); near-surface mounted (NSM), and continuous reinforcement embedded at the ends (CREatE), a new technique that prevents premature CFRP debonding. The main goals of this study were three-fold: to understand and compare the fire behaviour of the strengthening techniques, namely the CREatE technique (yet to be studied); to assess the efficiency of the fire protection schemes (constant thickness vs. increased thickness at the CFRP anchorage zones) in extending the fire resistance of the CFRP systems; and, based on the experimental results and data available in the literature, to propose “critical” temperatures for the fire design of CFRP-strengthened RC members. The results obtained show that: (i) without protection, the CREatE technique presented higher fire resistance than the alternative NSM and EBR techniques (24 min vs. 16 min and 2 min); (ii) with fire protection, regardless of its geometry, the NSM and CREatE techniques presented a similar fire resistance (both above 120 min), higher than the EBR technique (less than 60 min); and (iii) the “critical” temperatures for each technique were defined as 1.0Tg, 2.5Tg and 3.0Tg for EBR, NSM and CREatE, respectively, with Tg being the glass transition temperature of the adhesive, defined based on the onset of the storage modulus curve decay from dynamic mechanical analysis. © 2021 Elsevier Ltd

Mochão, Hugo, Daniel Gonçalves, Leonardo Alexandre, Carolina Castro, Duarte Valério, Pedro Barahona, Daniel Moreira-Gonçalves, Paulo Matos da Costa, Rui Henriques, Lúcio L. Santos, and others. "IPOscore: An interactive web-based platform for postoperative surgical complications analysis and prediction in the oncology domain." Computer Methods and Programs in Biomedicine. 219 (2022): 106754. Abstract
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Pinto, José, João Antunes, João Ramos, Rafael S. Costa, and Rui Oliveira. "Modeling and optimization of bioreactor processes." Current Developments in Biotechnology and Bioengineering. Elsevier, 2022. 89-115. Abstract
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Carvalho, Fernanda, Pedro Sousa, Nuno Leal, Joaquim Simão, Elissavet Kavoulaki, Maria Margarida Lima, Teresa Pereira da Silva, Hugo Águas, Giuseppina Padeletti, and João Pedro Veiga. "Mortars from the Palace of Knossos in Crete, Greece: A Multi-Analytical Approach." Minerals. 12 (2022): 30. Abstract
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Amarante dos Santos, Filipe, and Fernando Fraternali. "Novel magnetic levitation systems for the vibration control of lightweight structures and artworks." Structural Control and Health Monitoring (2022). AbstractWebsite
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Micaelo, R., M. Carvalho, R. Almeida, W. - Y. Gao, and H. Biscaia. "Numerical Analysis on the Bond Performance of Different Anchored Joints under Monotonic and Cyclic Pull-push Loading." Journal of Applied and Computational Mechanics. 8 (2022): 388-404. AbstractWebsite

This study aims to mitigate the gap of knowledge on the cyclic bond behaviour of Carbon Fiber Reinforced Polymer (CFRP) bonded onto a steel substrate. The Distinct Element Method was used to model different bonding techniques such asExternally Bonded Reinforcement (for reference purposes); the linear increase of the width of the CFRP composite; theassumption of a mixed adhesive; and using an additional steel plate bonded on the top of the CFRP. Compared with themonotonic loading simulations, the load capacity and ductility of the joints with the lowest overlapped bonded lengths decreasedwith the number of cycles. However, the strength of the CFRP-to-steel joints was not affected if the overlapping bonded joint hada long length © 2022. Published by Shahid Chamran University of Ahvaz

Panigrahi, S., T. Calmeiro, MJ Mendes, H. Águas, E. Fortunato, and R. Martins. "Observation of Grain Boundary Passivation and Charge Distribution in Perovskite Films Improved with Anti-solvent Treatment." Journal of Physical Chemistry C. 126 (2022): 19367-19375. AbstractWebsite
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Alagador, Diogo, and Jorge Orestes Cerdeira. "Operations research applicability in spatial conservation planning." Journal of Environmental Management. 315 (2022): 115172. AbstractWebsite

A large fraction of the current environmental crisis derives from the large rates of human-driven biodiversity loss. Biodiversity conservation questions human practices towards biodiversity and, therefore, largely conflicts with ordinary societal aspirations. Decisions on the location of protected areas, one of the most convincing conservation tools, reflect such a competitive endeavor. Operations Research (OR) brings a set of analytical models and tools capable of resolving the conflicting interests between ecology and economy. Recent technological advances have boosted the size and variety of data available to planners, thus challenging conventional approaches bounded on optimized solutions. New models and methods are needed to use such a massive amount of data in integrative schemes addressing a large variety of concerns. This study provides an overview on the past, present and future challenges that characterize spatial conservation models supported by OR. We discuss the progress of OR models and methods in spatial conservation planning and how those models may be optimized through sophisticated algorithms and computational tools. Moreover, we anticipate possible panoramas of modern spatial conservation studies supported by OR and we explore possible avenues for the design of optimized interdisciplinary collaborative platforms in the era of Big Data, through consortia where distinct players with different motivations and services meet. By enlarging the spatial, temporal, taxonomic and societal horizons of biodiversity conservation, planners navigate around multiple socioecological/environmental equilibria and are able to decide on cost-effective strategies to improve biodiversity persistence under complex environments.

Haque, Sirazul, Miguel Alexandre, Clemens Baretzky, Daniele Rossi, Francesca De Rossi, António T. Vicente, Francesca Brunetti, Hugo Águas, Rute A. S. Ferreira, Elvira Fortunato, Matthias Auf der Maur, Uli Würfel, Rodrigo Martins, and Manuel J. Mendes. "Photonic-Structured Perovskite Solar Cells: Detailed Optoelectronic Analysis." ACS Photonics. 9 (2022): 2408-2421. AbstractWebsite
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Isufi, Brisid, André Almeida, Rui Marreiros, António Pinho Ramos, and Válter Lúcio. "Slab–column connection punching and ductility improvement methods for seismic response of buildings with flat slabs." Structural Concrete. 23 (2022): 1385-1398. AbstractWebsite
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Antão, A. N., and M. Vicente da Silva. "Three-dimensional Limit Analysis with Lade-Duncan criterion." Géotechnique Letters. 12 (2022): 1-21. AbstractWebsite

The paper describes the three-dimensional numerical implementation of the Lade-Duncan criterion in a finite element limit analysis (FELA) code. Validation is done using examples with a known solution. To conclude the proposed numerical tool is applied to the calculation of the ultimate bearing capacity of square footing.

Biscaia, H. C., J. Canejo, S. Zhang, and R. Almeida. "Using digital image correlation to evaluate the bond between carbon fibre-reinforced polymers and timber." Structural Health Monitoring. 21 (2022): 534-557. AbstractWebsite

The use of optic measurements such as digital image correlation to take strain measurements of fibre-reinforced polymers bonded to a substrate has been on the increase recently. This technique has proven to be useful to fully characterize the bond behaviour between two materials. Although modern digital cameras can take high-definition photos, this task is far from simple due to the tiny displacements that need to be measured. Consequently, digital image correlation measurements lead to relative errors that, at an initial stage of the debonding process, are higher than those calculated close to the debonding of the fibre-reinforced polymer from the substrate. This study aims to evaluate and analyse the use of the digital image correlation technique on the bond between carbon fibre-reinforced polymer laminates and timber when subjected to a pull-out load consistent with fracture Mode II. To allow the quantification of the relative errors obtained from the digital image correlation measurements during the full debonding process, several strain gauges were used to measure the strains in the carbon fibre-reinforced polymer composite. The accuracy of the digital image correlation measurements is analysed by comparing it with those obtained from the strain gauges, which is a very well-established measuring technique. Another contribution of this study is to check the versatility of the digital image correlation measurements on a broader range of situations. To that end, several timber prisms were bonded with seven different bonding techniques with and without the installation of a mechanical anchorage at the carbon fibre-reinforced polymer unpulled end. The results showed that the digital image correlation technique was able to track the slips calculated from the strain gauge measurements until the debonding load, but after that, some difficulties to measure the displacements of the anchored carbon fibre-reinforced polymer-to-timber joints were detected. The digital image correlation technique also over predicted bond stresses when compared with those taken from the strain gauges, which led to bond–slip relationships with higher bond stresses. © The Author(s) 2021.

Boillos, J. M., D. Cortina-Gil, J. Benlliure, J. L. Rodr{\'ıguez-Sánchez, H. Alvarez-Pol, L. Atar, T. Aumann, V. V. Avdeichikov, S. Beceiro-Novo, D. Bemmerer, C. A. Bertulani, K. Boretzky, M. J. G. Borge, M. Caamano, C. Caesar, E. Casarejos, W. Catford, J. Cederkäll, M. Chartier, L. Chulkov, E. Cravo, R. N. P. Crespo, I. Dillmann, Diaz P. Fernandez, Z. Elekes, J. Enders, O. Ershova, A. Estrade, F. Farinon, L. M. Fraile, M. Freer, Galaviz D. Redondo, H. Geissel, R. Gernhäuser, P. Golubev, K. Göbel, J. Hagdahl, T. Heftrich, M. Heil, M. Heine, A. Heinz, A. Henriques, M. Holl, A. Hufnagel, A. Ignatov, H. T. Johansson, B. Jonson, J. Kahlbow, N. Kalantar-Nayestanaki, R. Kanungo, A. Kelic-Heil, A. Knyazev, T. Kröll, N. Kurz, M. Labiche, C. Langer, T. Le Bleis, R. Lemmon, S. Lindberg, J. F. D. C. Machado, J. Marganiec, A. Movsesyan, E. Nacher, M. A. Najafi, T. Nilsson, C. Nociforo, V. Panin, S. Paschalis, A. Perea, M. Petri, S. Pietri, R. Plag, R. Reifarth, G. Ribeiro, C. Rigollet, D. M. Rossi, M. Röder, D. Savran, H. Scheit, H. Simon, O. Sorlin, I. J. Syndikus, J. T. Taylor, O. Tengblad, R. Thies, Y. Togano, M. Vandebrouck, P. J. F. Velho, V. Volkov, A. Wagner, F. Wamers, H. Weick, C. Wheldon, G. L. Wilson, J. S. Winfield, P. Woods, D. Yakorev, M. Zhukov, A. Zilges, and K. Zuber. "{Isotopic cross sections of fragmentation residues produced by light projectiles on carbon near $400A$ MeV}." (2022): 1-13. Abstract

Phys. Rev. C 105, 014611 (2022). doi:10.1103/PhysRevC.105.014611

Ménesguen, Y., M. - C. Lépy, Y. Ito, M. Yamashita, S. Fukushima, T. Tochio, M. Polasik, K. Słabkowska, Ł. Syrocki, P. Indelicato, J. P. Gomilsek, J. P. Marques, J. M. Sampaio, J. Machado, P. Amaro, M. Guerra, J. P. Santos, and F. Parente. "{Structure of single KL$^0$-, double KL$^1$-, and triple KL$^2$- ionization in Mg, Al, and Si targets induced by photons, and their absorption spectra}." Radiation Physics and Chemistry. 194 (2022): 110048. AbstractWebsite

Radiation Physics and Chemistry, 194 (2022) 110048. doi:10.1016/j.radphyschem.2022.110048

Esteves, Carina, Susana I. C. J. Palma, Henrique M. A. Costa, Cláudia Alves, Gonçalo M. C. Santos, Efthymia Ramou, Ana Luísa Carvalho, Vitor Alves, and Ana C. A. Roque. "{Tackling Humidity with Designer Ionic Liquid-Based Gas Sensing Soft Materials}." Advanced Materials (2022). Abstract

Relative humidity is simultaneously a sensing target and a contaminant in gas and volatile organic compound (VOC) sensing systems, where strategies to control humidity interference are required. An unmet challenge is the creation of gas-sensitive materials where the response to humidity is controlled by the material itself. Here, humidity effects are controlled through the design of gelatin formulations in ionic liquids without and with liquid crystals as electrical and optical sensors, respectively. In this design, the anions [DCA]− and [Cl]− of room temperature ionic liquids from the 1-butyl-3-methylimidazolium family tailor the response to humidity and, subsequently, sensing of VOCs in dry and humid conditions. Due to the combined effect of the materials formulations and sensing mechanisms, changing the anion from [DCA]− to the much more hygroscopic [Cl]−, leads to stronger electrical responses and much weaker optical responses to humidity. Thus, either humidity sensors or humidity-tolerant VOC sensors that do not require sample preconditioning or signal processing to correct humidity impact are obtained. With the wide spread of 3D- and 4D-printing and intelligent devices, the monitoring and tuning of humidity in sustainable biobased materials offers excellent opportunities in e-nose sensing arrays and wearable devices compatible with operation at room conditions.

2021
{Henriques Ferreira}, Sofia, Ana Rovisco, Andreia dos Santos, Hugo Águas, Rui Igreja, Pedro Barquinha, Elvira Fortunato, and Rodrigo Martins. "{Porous ZnO Nanostructures Synthesized by Microwave Hydrothermal Method for Energy Harvesting Applications}." Nanopores. Eds. Sadia Ameen, Shaheer M. Akhtar, and Hyung-Shik Shin. IntechOpen, 2021. Abstract

Abstract Long-haul travel does not constitute an obstacle for tourists to travel and is fast gaining the attention of tourists in new and unique experiences. This study was conducted to identify the long-haul travel motivation by international tourists to Penang. A total of 400 respondents participated in this survey, conducted around the tourist attractions in Penang, using cluster random sampling. However, only 370 questionnaires were only used for this research. Data were analysed using SPSS software 22 version. The findings, ‘knowledge and novelty seeking' were the main push factors that drove long-haul travel by international tourists to Penang. Meanwhile, the main pull factor that attracts long- haul travel by international tourists to Penang was its ‘culture and history'. Additionally, there were partly direct and significant relationships between socio-demographic, trip characteristics and travel motivation (push factors and pull factors). Overall, this study identified the long-haul travel motivations by international tourists to Penang based on socio-demographic, trip characteristics and travel motivation and has indirectly helped in understanding the long-haul travel market particularly for Penang and Southeast Asia. This research also suggested for an effective marketing and promotion strategy in pro- viding useful information that is the key to attract international tourists to travel long distances. Keywords:

Ferreira, Sofia Henriques, Maria Morais, Daniela Nunes, Maria João Oliveira, Ana Rovisco, Ana Pimentel, Hugo Águas, Elvira Fortunato, and Rodrigo Martins. "{High UV and Sunlight Photocatalytic Performance of Porous ZnO Nanostructures Synthesized by a Facile and Fast Microwave Hydrothermal Method}." Materials. 14 (2021): 2385. AbstractWebsite

The degradation of organic pollutants in wastewaters assisted by oxide semiconductor nanostructures has been the focus of many research groups over the last decades, along with the synthesis of these nanomaterials by simple, eco-friendly, fast, and cost-effective processes. In this work, porous zinc oxide (ZnO) nanostructures were successfully synthesized via a microwave hydrothermal process. A layered zinc hydroxide carbonate (LZHC) precursor was obtained after 15 min of synthesis and submitted to different calcination temperatures to convert it into porous ZnO nanostructures. The influence of the calcination temperature (300, 500, and 700 °C) on the morphological, structural, and optical properties of the ZnO nanostructureswas investigated. All ZnO samples were tested as photocatalysts in the degradation of rhodamine B (RhB) under UV irradiation and natural sunlight. All samples showed enhanced photocatalytic activity under both light sources, with RhB being practically degraded within 60 min in both situations. The porous ZnO obtained at 700 °C showed the greatest photocatalytic activity due to its high crystallinity, with a degradation rate of 0.091 and 0.084 min−1 for UV light and sunlight, respectively. These results are a very important step towards the use of oxide semiconductors in the degradation of water pollutants mediated by natural sunlight.

Peres, Ricardo Silva, Miguel Azevedo, Sara Oleiro Araújo, Magno Guedes, Fábio Miranda, and José Barata. "Generative Adversarial Networks for Data Augmentation in Structural Adhesive Inspection." Applied Sciences. 11 (2021): 3086. AbstractWebsite
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Grilo, Filipe, Chintan Shah, Steffen Kühn, René Steinbrügge, Keisuke Fujii, José Marques, Ming Feng Gu, José Paulo Santos, José Crespo R. López-Urrutia, and Pedro Amaro. "Comprehensive Laboratory Measurements Resolving the {LMM} Dielectronic Recombination Satellite Lines in Ne-like Fe xvii Ions." The Astrophysical Journal. 913 (2021): 140. AbstractWebsite
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