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2022
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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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

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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Ramos, António, Brisid Isufi, Rui Marreiros, Mária Bolešová, and Katarina Gajdošová. "Rational use of HPFRC in slab – column connections under reversed horizontal cyclic loading." Engineering Structures. 270 (2022). AbstractWebsite
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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

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:

Bučiūnienė, Ilona, B. Goštautaitė, António Brandão Moniz, and Irina Liubertė. "Hiring robots: How HRM shapes the development of human capital." 36th EIASM workshop on strategic human resource management. online: EIASM, 2021.
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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{Isabel Bento Rovisco}, Ana, Rita Branquinho, Joana {Vaz Pinto}, Rodrigo Martins, Elvira Fortunato, and Pedro Barquinha. "{Hydrothermal Synthesis of Zinc Tin Oxide Nanostructures for Photocatalysis, Energy Harvesting and Electronics}." Novel Nanomaterials. IntechOpen, 2021. Abstract
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Rovisco, Ana, Rita Branquinho, Rodrigo Martins, Elvira Fortunato, and Pedro Barquinha. "{Microwave-Assisted Hydrothermal Synthesis of Zn2SnO4 Nanostructures for Photocatalytic Dye Degradation}." Materials Proceedings. 4 (2021): 92. AbstractWebsite

Zinc-tin oxide (ZTO) nanostructures appear as one of the most promising material systems for a new generation of nanodevices. In this work, a microwave-assisted hydrothermal synthesis to produce different shapes of Zn2SnO4 nanostructures (nanoparticles, octahedrons and nanoplates) is presented. Reproducible and homogeneous results were obtained with the advantage of reducing up to 20 h the synthesis time when compared to using a conventional oven. Furthermore, the photocatalytic activity of the Zn2SnO4 nanostructures in the degradation of rhodamine B under UV light was studied. Zn2SnO4 nanoparticles demonstrated better performance with >90% of degradation being achieved in 2.5 h.

Boavida, Nuno, António Brandão Moniz, R. Naumann, and Isabel Roque. "How is labour organised in Portuguese digital platforms?." Final International Conference of the Project Crowdwork: Platform work – Finding new strategies to organize in Europe. online: European Commission, 2021.
Boavida, Nuno, António B. Moniz, Reinhard Naumann, Isabel Roque, and Raquel Azevedo Case studies on digital labour platforms in Portugal: 2nd National Report of Project Crowdwork. Lisbon: CICS.NOVA, 2021. Abstract

The so called “crowd work” is an employment form that uses a digital platform to enable organisations or individuals to access other organisations or individuals to solve specific problems or to provide specific services in exchange for payment (Valenduc and Vendramin, 2016). There are many alternative terms for crowd work used in European member states, such as crowd sourcing, crowd employment, sharing economy, platform economy, gig economy, on-demand economy, collaborative economy, Peer-to-peer economy, among others (Eurofound 2018). Recently, the term “digital platform work” has developed recently to be dominant in the literature to refer to sectors where this technology has arrived. Accordingly, this report will proceed using the latter term. These forms of online intermediation have expanded from creative and high-skilled professional activities that became virtualised as a result of digitalisation to a variety of other services and activities, traditionally delivered by self-employed, that involve the maintenance or repair of material commodities or the delivery of services in person, such as cleaning, gardening, household maintenance and transport (Huws, 2017). As a result of this, workers profiles vary from highly skilled IT and creative professionals to very unskilled workers. It has been also noted that many digital platform workers are young people looking for extra income such as students, unemployed or carers (Valenduc and Vendramin, 2016). The main Portuguese reference about work in digital platforms is fused with the Uber app. Its controversial arrival in 2014 triggered fierce responses from several groups. The main legislative reference on digital platform work is the ‘Uber law’. The symbolism of the app expressed as ‘Uberization’ became synonymous of the ‘new’ precariat, seen as a hassle of technology and an attack to organized labour in the country. There are also regulations for Airbnb at state, regional and municipal level intended to limit the number of lodgings in certain areas where touristic activities are very intense. In general, the other platforms are not covered by specific regulations.

Baumann, Manuel, Jen Peters, H. Ersoy, Marcel Weil, Guy Fournier, António Brandão Moniz, and Nelson C. Martins. "Decision making support for the selection of stationary batteries." Energy Transition and Sustainability Conference (APEEN 2021). online: CENSE, 2021.
Krauth, Julian J., Karsten Schuhmann, Marwan Abdou Ahmed, Fernando D. Amaro, Pedro Amaro, François Biraben, Tzu-Ling Chen, Daniel S. Covita, Andreas J. Dax, Marc Diepold, Luis M. P. Fernandes, Beatrice Franke, Sandrine Galtier, Andrea L. Gouvea, Johannes Götzfried, Thomas Graf, Theodor W. Hänsch, Jens Hartmann, Malte Hildebrandt, Paul Indelicato, Lucile Julien, Klaus Kirch, Andreas Knecht, Yi-Wei Liu, Jorge Machado, Cristina M. B. Monteiro, Françoise Mulhauser, Boris Naar, Tobias Nebel, François Nez, Joaquim M. F. dos Santos, José Paulo Santos, Csilla I. Szabo, David Taqqu, João F. C. A. Veloso, Jan Vogelsang, Andreas Voss, Birgit Weichelt, Randolf Pohl, Aldo Antognini, and Franz Kottmann. "Measuring the $\upalpha$-particle charge radius with muonic helium-4 ions." Nature. 589 (2021): 527-531. AbstractWebsite
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Teixeira, Silvia Soreto, Manuel PF Graça, José Lucas, Manuel Almeida Valente, Paula I. P. Soares, Maria Carmo Lança, Tânia Vieira, Jorge Carvalho Silva, João Paulo Borges, Luiza-Izabela Jinga, Gabriel Socol, Cristiane Mello Salgueiro, José Nunes, and Luís C. Costa. "Nanostructured LiFe5O8 by a Biogenic Method for Applications from Electronics to Medicine." Nanomaterials. 11 (2021): 193. AbstractWebsite

The physical properties of the cubic and ferrimagnetic spinel ferrite LiFe5O8 has made it an attractive material for electronic and medical applications. In this work, LiFe5O8 nanosized crystallites were synthesized by a novel and eco-friendly sol-gel process, by using powder coconut water as a mediated reaction medium. The dried powders were heat-treated (HT) at temperatures between 400 and 1000 °C, and their structure, morphology, electrical and magnetic characteristics, cytotoxicity, and magnetic hyperthermia assays were performed. The heat treatment of the LiFe5O8 powder tunes the crystallite sizes between 50 nm and 200 nm. When increasing the temperature of the HT, secondary phases start to form. The dielectric analysis revealed, at 300 K and 10 kHz, an increase of $ε$′ (≈10 up to ≈14) with a tan$δ$ almost constant (≈0.3) with the increase of the HT temperature. The cytotoxicity results reveal, for concentrations below 2.5 mg/mL, that all samples have a non-cytotoxicity property. The sample heat-treated at 1000 °C, which revealed hysteresis and magnetic saturation of 73 emu g−1 at 300 K, showed a heating profile adequate for magnetic hyperthermia applications, showing the potential for biomedical applications.

Amaro, P., J. P. Santos, S. Bhattacharyya, T. K. Mukherjee, and J. K. Saha. "Stabilization method with the relativistic configuration-interaction calculation applied to two-electron resonances." Physical Review A. 103 (2021). AbstractWebsite
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Krauth, Julian J., Karsten Schuhmann, Marwan Abdou Ahmed, Fernando D. Amaro, Pedro Amaro, Fran{\c c}ois Biraben, Tzu-Ling Chen, Daniel S. Covita, Andreas J. Dax, Marc Diepold, Luis M. P. Fernandes, Beatrice Franke, Sandrine Galtier, Andrea L. Gouvea, Johannes Götzfried, Thomas Graf, Theodor W. Hänsch, Jens Hartmann, Malte Hildebrandt, Paul Indelicato, Lucile Julien, Klaus Kirch, Andreas Knecht, Yi-Wei Liu, Jorge Machado, Cristina M. B. Monteiro, Fran{\c c}oise Mulhauser, Boris Naar, Tobias Nebel, Fran{\c c}ois Nez, Joaquim M. F. dos Santos, José Paulo Santos, Csilla I. Szabo, David Taqqu, João F. C. A. Veloso, Jan Vogelsang, Andreas Voss, Birgit Weichelt, Randolf Pohl, Aldo Antognini, and Franz Kottmann. "{Measuring the $\alpha$-particle charge radius with muonic helium-4 ions}." Nature. 589 (2021): 527-531. AbstractWebsite

The energy levels of hydrogen-like atomic systems can be calculated with great precision. Starting from their quantum mechanical solution, they have been refined over the years to include the electron spin, the relativistic and quantum field effects, and tiny energy shifts related to the complex structure of the nucleus. These energy shifts caused by the nuclear structure are vastly magnified in hydrogen-like systems formed by a negative muon and a nucleus, so spectroscopy of these muonic ions can be used to investigate the nuclear structure with high precision. Here we present the measurement of two 2S–2P transitions in the muonic helium-4 ion that yields a precise determination of the root-mean-square charge radius of the $\alpha$ particle of 1.67824(83) femtometres. This determination from atomic spectroscopy is in excellent agreement with the value from electron scattering1, but a factor of 4.8 more precise, providing a benchmark for few-nucleon theories, lattice quantum chromodynamics and electron scattering. This agreement also constrains several beyond-standard-model theories proposed to explain the proton-radius puzzle2–5, in line with recent determinations of the proton charge radius6–9, and establishes spectroscopy of light muonic atoms and ions as a precise tool for studies of nuclear properties. The 2S–2P transitions in muonic helium-4 ions are measured using laser spectroscopy and used to obtain an $\alpha$-particle charge-radius value five times more precise than that from electron scattering.

dos Santos, Andreia, Filipe Sabino, Ana Rovisco, Pedro Barquinha, Hugo Águas, Elvira Fortunato, Rodrigo Martins, and Rui Igreja. "{Optimization of ZnO Nanorods Concentration in a Micro-Structured Polymeric Composite for Nanogenerators}." Chemosensors. 9 (2021): 27. AbstractWebsite

The growing use of wearable devices has been stimulating research efforts in the development of energy harvesters as more portable and practical energy sources alternatives. The field of piezoelectric nanogenerators (PENGs) and triboelectric nanogenerators (TENGs), especially employing zinc oxide (ZnO) nanowires (NWs), has greatly flourished in recent years. Despite its modest piezoelectric coefficient, ZnO is very attractive due to its sustainable raw materials and the facility to obtain distinct morphologies, which increases its multifunctionality. The integration of ZnO nanostructures into polymeric matrices to overcome their fragility has already been proven to be fruitful, nevertheless, their concentration in the composite should be optimized to maximize the harvesters' output, an aspect that has not been properly addressed. This work studies a composite with variable concentrations of ZnO nanorods (NRs), grown by microwave radiation assisted hydrothermal synthesis, and polydimethylsiloxane (PDMS). With a 25 wt % ZnO NRs concentration in a composite that was further micro-structured through laser engraving for output enhancement, a nanogenerator (NG) was fabricated with an output of 6 V at a pushing force of 2.3 N. The energy generated by the NG could be stored and later employed to power small electronic devices, ultimately illustrating its potential as an energy harvesting device.

Rovisco, Ana, Rita Branquinho, Jonas Deuermeier, Tomás Freire, Elvira Fortunato, Rodrigo Martins, and Pedro Barquinha. "{Shape Effect of Zinc-Tin Oxide Nanostructures on Photodegradation of Methylene Blue and Rhodamine B under UV and Visible Light}." ACS Applied Nano Materials. 4 (2021): 1149-1161. AbstractWebsite
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Araújo, Sara Oleiro, Ricardo Silva Peres, José Barata, Fernando Lidon, and JOSÉ COCHICHO RAMALHO. "Characterising the Agriculture 4.0 Landscape—Emerging Trends, Challenges and Opportunities." Agronomy. 11 (2021): 667. AbstractWebsite
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Silva, Carlos, Jorge Martins, Jonas Deuermeier, Maria Elias Pereira, Ana Rovisco, Pedro Barquinha, João Goes, Rodrigo Martins, Elvira Fortunato, and Asal Kiazadeh. "{Towards Sustainable Crossbar Artificial Synapses with Zinc-Tin Oxide}." Electronic Materials. 2 (2021): 105-115. AbstractWebsite

In this article, characterization of fully patterned zinc-tin oxide (ZTO)-based memristive devices with feature sizes as small as 25 µm2 is presented. The devices are patterned via lift-off with a platinum bottom contact and a gold-titanium top contact. An on/off ratio of more than two orders of magnitude is obtained without the need for electroforming processes. Set operation is a current controlled process, whereas the reset is voltage dependent. The temperature dependency of the electrical characteristics reveals a bulk-dominated conduction mechanism for high resistance states. However, the charge transport at low resistance state is consistent with Schottky emission. Synaptic properties such as potentiation and depression cycles, with progressive increases and decreases in the conductance value under 50 successive pulses, are shown. This validates the potential use of ZTO memristive devices for a sustainable and energy-efficient brain-inspired deep neural network computation.

Boavida, Nuno, António Brandão Moniz, Reinhard Naumann, Raquel Azevedo, Isabel Roque, Yuliya Kuznetsova, and Marina Peliz. "Digital work platforms – The diversity of collective representation in Portugal." Working on Platforms – Fighting for Labour and Social Rights. online: Práxis - Trabalho e Sindicalismo, 2021.
Buciuniene, Ilona, Bernadeta Goštautaitė, António B. Moniz, and Irina Liubertė. "Hiring robots: How HRM shapes the development of human capital." 36th Workshop on Strategic Human Resource Management. online: European Institute for Advanced Studies in Management, 2021. programme_may_27-28_2021_eism.pdf
Beccari, Victor, Felipe Lima Pinheiro, Ivan Nunes, Luiz Eduardo Anelli, Octávio Mateus, and Fabiana Rodrigues Costa. "Osteology of an exceptionally well-preserved tapejarid skeleton from Brazil: Revealing the anatomy of a curious pterodactyloid clade." PLOS ONE. 16.8 (2021): e0254789-. Abstractbeccari_et_al_2021.pdfWebsite

A remarkably well-preserved, almost complete and articulated new specimen (GP/2E 9266) of Tupandactylus navigans is here described for the Early Cretaceous Crato Formation of Brazil. The new specimen comprises an almost complete skeleton, preserving both the skull and post-cranium, associated with remarkable preservation of soft tissues, which makes it the most complete tapejarid known thus far. CT-Scanning was performed to allow the assessment of bones still covered by sediment. The specimen can be assigned to Tupa. navigans due to its vertical supra-premaxillary bony process and short and rounded parietal crest. It also bears the largest dentary crest among tapejarine pterosaurs and a notarium, which is absent in other representatives of the clade. The new specimen is here regarded as an adult individual. This is the first time that postcranial remains of Tupa. navigans are described, being also an unprecedented record of an articulated tapejarid skeleton from the Araripe Basin.