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2021
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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Ensina, Ana, Patr{\'ı}cia M. Carvalho, Jorge Machado, Maria Lu{\'ı}sa Carvalho, Diogo Casal, Diogo Pais, José Paulo Santos, António A. Dias, and Sofia Pessanha. "Analysis of human tissues using Energy Dispersive X Ray Fluorescence – Dark matrix determination for the application to cancer research." Journal of Trace Elements in Medicine and Biology. 68 (2021): 126837. AbstractWebsite
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Wain, Alison, Diogo Castro, {Maria Fernanda} Rollo, Frederico Nogueira, Gon{\c c}alo Santos, {Maria Gra{\c da c}a} Filipe, Isabel Tissot, {Jorge Miguel} Sampaio, {José Paulo} Santos, Manuel Lemos, Marta Manso, Matthias Tissot, Mauro Guerra, Miles Oglethorpe, Pedro Amaro, Pedro Pedroso, Rui Silva, Sofia Pessanha, and {Tiago A. N. } Silva Cultura Material, Cultura Científica: Património Industrial para o Futuro. Portugal: Faculdade de Ciências e Tecnologia, Universidade Nova de Lisboa, 2021. Abstract

Material, Culture, Scientific Culture: Industrial Heritage for the Future

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.

Conti, Simone, Emanuel Tschopp, G. Sala, and Octavio Mateus. "Multibody simulations of diplodocid tail motion." Annual conference of the European Association of Vertebrate Palaeontologists. European Association of Vertebrate Palaeontologists, 2021. conti_et_al_2021_diplodocid_tail._eavp_abstract.pdf
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
Ferrás, L., M. L. Morgado, and M. Rebelo. "A distributed order viscoelastic model for small deformations." SYMCOMP 2021. Evora, Portugal 2021.
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.

Marx, Miguel P., Octávio Mateus, Michael J. Polcyn, Anne S. Schulp, Olímpio A. Gonçalves, and Louis L. Jacobs. "The cranial anatomy and relationships of Cardiocorax mukulu (Plesiosauria: Elasmosauridae) from Bentiaba, Angola." PLOS ONE. 16.8 (2021): e0255773-. Abstractmarx_et_al_2021_cardiocorax_angola.pdfWebsite

We report a new specimen of the plesiosaur Cardiocorax mukulu that includes the most complete plesiosaur skull from sub-Saharan Africa. The well-preserved three-dimensional nature of the skull offers rare insight into the cranial anatomy of elasmosaurid plesiosaurians. The new specimen of Cardiocorax mukulu was recovered from Bentiaba, Namibe Province in Angola, approximately three meters above the holotype. The new specimen also includes an atlas-axis complex, seventeen postaxial cervical vertebrae, partial ribs, a femur, and limb elements. It is identified as Cardiocorax mukulu based on an apomorphy shared with the holotype where the cervical neural spine is approximately as long anteroposteriorly as the centrum and exhibits a sinusoidal anterior margin. The new specimen is nearly identical to the holotype and previously referred material in all other aspects. Cardiocorax mukulu is returned in an early-branching or intermediate position in Elasmosauridae in four out of the six of our phylogenetic analyses. Cardiocorax mukulu lacks the elongated cervical vertebrae that is characteristic of the extremely long-necked elasmosaurines, and the broad skull with and a high number of maxillary teeth (28–40) which is characteristic of Aristonectinae. Currently, the most parsimonious explanation concerning elasmosaurid evolutionary relationships, is that Cardiocorax mukulu represents an older lineage of elasmosaurids in the Maastrichtian.

Soares, Paula I. P., Joana Romao, Ricardo Matos, Jorge Carvalho Silva, and Joao Paulo Borges. "Design and engineering of magneto-responsive devices for cancer theranostics: Nano to macro perspective." 116 (2021): 100742. Abstract
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Ramanaiah, S. V., C. M. Cordas, S. Matias, and L. P. Fonseca. "In situ electrochemical characterization of a microbial fuel cell biocathode running on wastewater." Catalysts. 11.7 (2021). AbstractWebsite
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Delgado, Beatriz, Henrique Carrêlo, Mónica V. Loureiro, Ana C. Marques, João Paulo Borges, and Maria Teresa Cidade. "Injectable hydrogels with two different rates of drug release based on pluronic/water system filled with poly (ε-caprolactone) microcapsules." 56.23 (2021): 13416-13428. Abstract
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Fiévet, Anouchka, Meriem Merrouch, Gaël Brasseur, Danaé Eve, Emanuele G. Biondi, Odile Valette, Sofia R. Pauleta, Alain Dolla, Zorah Dermoun, Bénédicte Burlat, and Corinne Aubert. "OrpR is a σ54-dependent activator using an iron-sulfur cluster for redox sensing in Desulfovibrio vulgaris Hildenborough." Molecular MicrobiologyMolecular Microbiology. 116.1 (2021): 231-244. AbstractWebsite

Abstract Enhancer binding proteins (EBPs) are key players of σ54-regulation that control transcription in response to environmental signals. In the anaerobic microorganism Desulfovibrio vulgaris Hildenborough (DvH), orp operons have been previously shown to be coregulated by σ54-RNA polymerase, the integration host factor IHF and a cognate EBP, OrpR. In this study, ChIP-seq experiments indicated that the OrpR regulon consists of only the two divergent orp operons. In vivo data revealed that (i) OrpR is absolutely required for orp operons transcription, (ii) under anaerobic conditions, OrpR binds on the two dedicated DNA binding sites and leads to high expression levels of the orp operons, (iii) increasing the redox potential of the medium leads to a drastic down-regulation of the orp operons expression. Moreover, combining functional and biophysical studies on the anaerobically purified OrpR leads us to propose that OrpR senses redox potential variations via a redox-sensitive [4Fe?4S]2+ cluster in the sensory PAS domain. Overall, the study herein presents the first characterization of a new Fe?S redox regulator belonging to the σ54-dependent transcriptional regulator family probably advantageously selected by cells adapted to the anaerobic lifestyle to monitor redox stress conditions.

Fernandes, Alexandra E., Octávio Mateus, Blanca Bauluz, Rute Coimbra, Lope Ezquerro, Carmen Núñez-Lahuerta, Calin Suteu, and Miguel Moreno-Azanza. "The Paimogo Dinosaur Egg Clutch Revisited: Using One of Portugal’s Most Notable Fossils to Exhibit the Scientific Method." Geoheritage. 13.3 (2021): 66. Abstractfernandes_et_al-2021-geoheritage.pdfWebsite

Found in the Upper Jurassic outcrops of Lourinhã, Portugal, and first published in 1997, the Paimogo dinosaur egg clutch is one of Portugal’s most remarkable fossils, with over one hundred eggs preserved in association with embryonic bones, of the allosauroid theropod Lourinhanosaurus. However, many questions about it have remained unanswered, even until the present day. After its discovery, this extraordinary fossil became the keystone of a small local museum, greatly kick-starting regional tourism, while also holding the fossils in trust for future generations to study. More than 20 years later, continually sustained paleontological interest from the public has even given rise to both a highly successful dinosaur theme park in the region and an aspiring UNESCO Geopark. Recently, a multidisciplinary team of preparators, paleontologists, sedimentologists, mineralogists, and geochemists revisited an unopened jacket from the original excavation using an array of techniques to address various questions. Studies are ongoing, but the corpus of information obtained and the methodologies utilized to gather data have offered an opportunity to design an exhibit around the history of the Paimogo clutch, highlighting the scientific methods involved, and asserting the importance of preserving geological heritage for the future, when new tools will doubtlessly become available to provide yet another new look at old fossils. Here, we describe our analytical procedures and present an innovative exhibit designed to introduce to the public the latest advances on the research behind an iconic piece of Portuguese geoheritage, increasing its value both as a research item and as an educational resource.

Nunes, M. J., C. M. Cordas, JJG Moura, J. P. Noronha, and L. C. Branco. "Screening of Potential Stress Biomarkers in Sweat Associated with Sports Training." Sports Medicine - Open. 7.1 (2021). AbstractWebsite
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Lima, Carlos D. L., Helena Coelho, Ana Gimeno, Filipa Trovão, Ana Diniz, Jorge S. Dias, Jesús Jiménez-Barbero, Francisco Corzana, Ana Luísa Carvalho, Eurico J. Cabrita, and Filipa Marcelo. "Structural insights into the molecular recognition mechanism of the cancer and pathogenic epitope, LacdiNAc by immune-related lectins." Chemistry – A European JournalChemistry – A European Journal. n/a.n/a (2021). AbstractWebsite

Interactions of glycan-specific epitopes to human lectin receptors represent novel immune checkpoints for investigating cancer and infection diseases. By employing a multidisciplinary approach that combines isothermal titration calorimetry, NMR spectroscopy, molecular dynamics simulations, and X-ray crystallography, we disclosed the molecular determinants that govern the recognition of the tumour and pathogenic glycobiomarker LacdiNAc (GalNAc?1-4GlcNAc, LDN), including their comparison with the ubiquitous LacNAc epitope (Gal?1-4GlcNAc, LN), by two human immune-related lectins, galectin-3 (hGal-3) and the macrophage galactose C-type lectin (hMGL). A different mechanism of binding and interactions is observed for the hGal-3/LDN and hMGL/LDN complexes, which explains the remarkable difference in the binding specificity of LDN and LN by these two lectins. The new structural clues reported herein are fundamental for the chemical design of mimetics targeting hGal-3/hMGL recognition process.

Baumann, Manuel, Jens Peters, Hüseyin Ersoy, Marcel Weil, Guy Fournier, António B. Moniz, and Nelson Chibeles Martins. "Decision making support for the selection of stationary batteries." Energy Transition and Sustainability Conference (APEEN 2021). online: CENSE, 2021.
Boavida, Nuno, António Brandão Moniz, and Marta Candeias. "Changes in productivity and labour relations: AI in the automotive sector in Portugal." International Colloquium GERPISA - Le Réseau International de L’Automobile. online: ENS Paris-Saclay, 2021. Abstract

New technologies, sustainability policies, protectionism and consumers preferences are pushing for the reorganization of the automotive cluster. (ILO, 2020) Due to recent technological advances derived from the application of AI in the domains of autonomous driving, connectivity, automation, and robotics, the automotive sector is evolving from the traditional, linear, product-oriented value chain to a mobility, service oriented one including new players (ILO, 2020). In fact, in the last years, several digital competences centers are supplying the automotive sector and have been installed in Portugal. These changes are put in place to enhance the product quality, to control costs and to improve productivity. The product shift is done to respond to new regulations on environmental protection, and to enable the control of some emergent market niches.
The paper will contribute to answer the question: what are the expectable changes in productivity due to the introduction of AI in the automotive sector and at new players in the automotive value chain in Portugal? Do they have impacts in traditional labour relations in the sector? Did the COVID-19 had an effect in the acceleration of such changes? Does the employment in the automotive sector changed with the recent automation trends in Portugal? Are there signs of improvement in qualifications with increases in automation? Or can we observe a clear job precarity in the automotive labour market with increased application of cyber physical systems in this sector? We want to develop this framework of questions to collect new data and obtain results that will be based on case studies from the automotive cluster. We will use, as well, secondary statistical analysis. Finally, changes in the productivity and labour market will be discussed in relation to the employment volume and skills in the automotive sector.
In this recently approved national project, we will focus on AI (cyber-physical systems, intelligent automation, robotics, IoT) as the most relevant emergent technology to understand the development of automation in this manufacturing sector (Geels et al., 2012; Moniz 2018). R&D investments in industrial processes in general may reflect productivity improvements derived from the increased automation process, but that may not be the general trend. Our empirical data are based until now on initial case studies from the automotive and components sector combined with database search by keywords that sign intelligence automation developments and AI applications selected from national R&D projects on robotics, machine learning, collaborative tools, human-machine interaction and autonomous systems, supported by European structural funds. The implications on industrial productivity and employment will be discussed in relation to automation trends in the automotive sector.

Peliz, Marina, Nuno Boavida, and António Brandão Moniz. "Portuguese Field Work on the Involvement of Social Partner at the Education and Training Systems." 2nd Scientific meeting of the project INVOLVE. online: Notus, 2021.
Conti, Simone, Octávio Mateus, and G. Sala. "Mechanical characterization of tibial bone material of an ostrich." Rossi V., Fanti F., Barbieri G., Cavalazzi B. & Scarponi D. (Editors) 2021. Paleodays 2021. Abstract Book del XXI Convegno della Società Paleontologica Italiana, live virtual edition: 127 pp. Bologna (Italy): University of Bologna, 2021. conti_et_al_2021_ostrich_bone.pdf