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2022
Viseu, F., A. Silva, H. Rocha, and P. Martins. "The graphical representation in the learning of functions by 10th grade students." Educación Matemática. 34.1 (2022): 186-213. AbstractWebsite

A exploração de diferentes representações promove a compreensão dos tópicos de funções. Partindo deste pressuposto, com este estudo pretende-se analisar o contributo da representação gráfica na aprendizagem da noção de função inversa e da paridade de uma função por alunos do 10.º ano de escolaridade e identificar dificuldades na exploração dessa representação. Na procura de responder a este objetivo, adotou-se uma abordagem qualitativa e interpretativa para compreender as ações dos alunos na resolução das tarefas
propostas. A análise das resoluções mostra que a representação gráfica serviu de suporte para a instituição das definições dos tópicos em estudo. E isto apesar de alguns alunos revelarem dificuldades ao interpretar e ao construir gráficos; ao identificar imagens e imagens inversas em gráficos de funções; ao representar determinadas características gráficas associadas a alguns conceitos, como é o caso da relação entre a paridade de uma função e a simetria na sua representação gráfica (confundindo eixo de simetria e de reflexão). Globalmente, este estudo mostra como a abordagem de conceitos a partir da representação gráfica pode contribuir para a sua compreensão.

Karlovich, Alexei, and Eugene Shargorodsky. "A lower estimate for weak-type Fourier multipliers." Complex Variables and Elliptic Equations. 67.3 (2022): 642-660.Website
Puértolas‐Pascual, E., A. Serrano‐Martínez, I. T. Kuzmin, and O. Mateus Neuroanatomy of the Cenomanian crocodylomorph Portugalosuchus. XIX Annual Conference of the European Association of Vertebrate Paleontologists., 2022. Abstractpuertolas-pascoal_et_al_2022_portugalosuchus_eavp_2022_abstract_volume.pdf

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Karlovich, Alexei, and Eugene Shargorodsky. "On an analogue of a theorem by Astala and Tylli." Archiv der Mathematik. 118 (2022): 73-77.Website
Diening, Lars, Oleksiy Karlovych, and Eugene Shargorodsky. "On interpolation of reflexive variable Lebesgue spaces on which the Hardy-Littlewood maximal operator is bounded." Georgian Mathematical Journal . 29.3 (2022): 347-352.Website
Karlovych, Oleksiy, and Eugene Shargorodsky. "On the essential norms of singular integral operators with constant coeffcients and of the backward shift." Proceedings of the American Mathematical Society B. 9 (2022): 60-70.Website
Puértolas-Pascual, E., A. Serrano-Martínez, I. T. Kuzmin, and O. Mateus Paleoneuroanatomía de Portugalosuchus, un cocodrilomorfo eusuquio del Cenomaniense de Portugal. XXXVII Jornadas SEP y V Congreso Ibérico de Paleontología, .Libro de resúmenes. Cuenca: ISBN 13: 978-84-09-44478-6, 2022. Abstractpuertolas-pascula_et_al_2022_portugalosuchus_jornadas_sep_cuenca_abstract_2022.pdf

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Şan, Mufit, Arnaldo Batista, Sara Russo, Filipa Esgalhado, Catarina Palma Reis, Fátima Serrano, and Manuel Ortigueira. "A Preliminary Exploration of the Placental Position Influence on Uterine Electromyography Using Fractional Modelling." Sensors. 5.22 (2022).
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.

de Miguel, Pablo Sanz, António B. Moniz, Nuno Boavida, Joan Antoni Serra, M. Pańków, G. Karoulas, Marina Peliz, and I. Papageorgiou Social partners’ involvement in dual vocational education and training (VET): a comparison of Greece, Spain, Poland and Portugal. Barcelona: Notus, 2022. Abstractsocial_partners_involvement_in_dual_vocatioanl_education_and_training_vet._a_comparison_of_greece_spain_poland_and_portugal.pdfWebsite

The research report presents the key findings from the INVOLVE project (VS/2020/0145). It contributes to the debates on the participation of social partners in dual VET governance under countries generally classified as state-centred, skills-formation regimes (Spain, Greece, Portugal and Poland). The research report analysed the actual role played by social partners in the dual VET systems in the selected countries at different governance levels and the extent to which trade unions and employer organisations are involved on an equal footing. It also formulates policy recommendations supporting collective responses to dual VET systems in the selected countries. Findings are based on desk research, fieldwork consisting of semi-structured interviews and mini-case studies and national scenarios developed by INVOLVE partners, on the basis of a scenario workshop methodology

Karlovych, Oleksiy, and Eugene Shargorodsky. "Toeplitz operators with non-trivial kernels and non-dense ranges on weak Hardy spaces." Toeplitz Operators and Random Matrices. In Memory of Harold Widom. Operator Theory: Advances and Applications, vol. 289. Eds. Estelle Basor, Albrecht ¨Böttcher, and Torsten Ehrhardt. Birkhäuser, 2022. 463-476.
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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Silva, Teresa P., Daniel de Oliveira, João P. Veiga, Vitor Lisboa, Jorge Carvalho, Alexandra M. Barreiros, Mathilda L. Coutinho, Eduardo Salas-Colera, and Rogério Vigário. "Contribution to the Understanding of the Colour Change in Bluish-Grey Limestones." Heritage. 5 (2022): 1479-1503. AbstractWebsite

Bluish-grey limestones have been extensively used as ornamental stones for decoration purposes in buildings, as well as in works of art, and accordingly, have been the target of intense exploration. In Portugal, the Jurassic limestone massif known as the Maciço Calcário Estremenho (MCE), has been the source of grey-coloured ornamental stones, namely the Azul Valverde (one of the most well-known bluish-grey limestones) and Atlantic Blue varieties, both of which may undergo colour changes in outdoor environments. In this sense, it is important to understand the sudden colour change from bluish-grey to yellow/beige in the same limestone block in a quarry, or even, what happens to the colour when polished limestone is placed outdoors. This study was undertaken using various techniques, namely XRF (X-ray fluorescence spectrometry), XRD (X-ray diffraction), SEM (scanning electron microscopy), DTA–TG (differential thermal analysis/thermogravimetry) and colourimetry. Synchrotron radiation was also used at the European Synchrotron Radiation Facility (ESRF, Grenoble, France) where XANES (X-ray Absorption Near Edge Structure) spectra at Fe K-edge were collected to ascertain the speciation state of Fe in different coloured zones of the limestone, previously checked by EDXRF (energy dispersive X-ray fluorescence). The presence of Fe2+ and Fe3+ are responsible for the greyish and yellow/brown colour, respectively. On the other hand, the UV radiation from the sun causes a quickened and severe bleaching/fading on the dark blue/grey polished limestone.

Muttoni, A., D. Coronelli, M. Lamperti Tornaghi, L. Martinelli, I. R. Pascu, A. Pinho Ramos, G. Tsionis, P. Bamonte, B. Isufi, and A. Setiawan. "Deformation capacity evaluation for flat slab seismic design." Bulletin of Earthquake Engineering. 20 (2022): 1619-1654. AbstractWebsite
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Pinto, José, Mykaella Mestre, J. Ramos, Rafael S. Costa, Gerald Striedner, and Rui Oliveira. "A general deep hybrid model for bioreactor systems: Combining first principles with deep neural networks." Computers & Chemical Engineering. 165 (2022): 107952. Abstract
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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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Caetano, Constantino, Maria Luísa Morgado, Paula Patrício, Andreia Leite, Ausenda Machado, André Torres, João Freitas Pereira, Sónia Namorado, Ana Sottomayor, André Peralta-Santos, and Baltazar Nunes. "Measuring the impact of COVID-19 vaccination and immunity waning: a modelling study for Portugal." Vaccine (2022). AbstractWebsite

Vaccination strategies to control COVID-19 have been ongoing worldwide since the end of 2020. Understanding their possible effect is key to prevent future disease spread. Using a modelling approach, this study intends to measure the impact of the COVID-19 Portuguese vaccination strategy on the effective reproduction number and explore three scenarios for vaccine effectiveness waning. Namely, the no-immunity-loss, 1-year and 3-years of immunity duration scenarios. We adapted an age-structured SEIR deterministic model and used Portuguese hospitalisation data for the model calibration. Results show that, although the Portuguese vaccination plan had a substantial impact in reducing overall transmission, it might not be sufficient to control disease spread. A significant vaccination coverage of those above 5 years old, a vaccine effectiveness against disease of at least 80% and softer non-pharmaceutical interventions (NPIs), such as mask usage and social distancing, would be necessary to control disease spread in the worst scenario considered. The immunity duration scenario of 1-year displays a resurgence of COVID-19 hospitalisations by the end of 2021, the same is observed in 3-year scenario although with a lower magnitude. The no-immunity-loss scenario presents a low increase in hospitalisations. In both the 1-year and 3-year scenarios, a vaccination boost of those above 65 years old would result in a 53% and 38% peak reduction of non-ICU hospitalisations, respectively. These results suggest that NPIs should not be fully phased-out but instead be combined with a fast booster vaccination strategy to reduce healthcare burden.

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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Figueiredo, Elin, Alexandra Rodrigues, João Fonte, Emmanuelle Meunier, Filipa Dias, Alexandre Lima, José Alberto Gonçalves, Luís Gonçalves-Seco, Filipe Gonçalves, Manuel F. C. Pereira, Rui JC Silva, and João P. Veiga. "Tin and Bronze Production at the Outeiro de Baltar Hillfort (NW Iberia)." Minerals. 12 (2022). AbstractWebsite

Findings of Iron Age metallurgical activities related to tin metal and mining are very rare. In the present work, we present a detailed study of the Outeiro de Baltar hillfort, dated to the Late Iron Age/Early Roman period, located in a place where 20th century tin mining work took place. Elemental and microstructural analysis by portable, micro and wavelength dispersive X-ray fluorescence spectrometry (pXRF, micro-XRF and WDXRF) and scanning electron microscopy with energy dispersion spectrometer (SEM-EDS) showed that metallurgical debris found at the archaeological site is related to tin smelting and binary and ternary bronze productions. Analysis of the artefacts of diverse typologies found at the site showed that a variety of metals and alloys were in circulation and use. Samples of tin ores (cassiterite) from the region were analyzed for comparison with an archaeological tin slag from the site. The analytical results point to the production of tin metal using local cassiterite and the production of bronze by directly adding cassiterite into a smelting process. Furthermore, data of remote sensing (airborne Light Detection and Ranging (LiDAR) and historical aerial imagery) and Geographical Information System (GIS) mapping were combined with archival mining documentation and maps to retrieve a landscape context for the site. The study showed that the place of the Outeiro de Baltar hillfort (NW Iberia) was mined periodically over time.

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
Cerdeira, Orestes J., and Pedro C. Silva. "A centrality notion for graphs based on Tukey depth." Applied Mathematics and Computation. 409 (2021): 126409. AbstractWebsite
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{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: