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2021
Ferrás, L., M. L. Morgado, and M. Rebelo. "A distributed order viscoelastic model for small deformations." SYMCOMP 2021. Evora, Portugal 2021.
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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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.

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.
Fernandes, Cláudio A., Alexei Yu. Karlovich, and Yuri I. Karlovich. "Banach algebras of Fourier multipliers equivalent at infinity to nice Fourier multipliers." Banach Journal of Mathematical Analysis. 15 (2021): 29.Website
Fernandes, Cláudio A., Alexei Yu. Karlovich, and Yuri I. Karlovich. "Calkin images of Fourier convolution operators with slowly oscillating symbols." Operator Theory, Functional Analysis and Applications. Operator Theory: Advances and Applications, vol 282. Basel: Birkhäuser Basel, 2021. 193-218.
Filipe, Luís, and K. T. Petrova. "Direct esterification of sucrose: novel lead-compounds against cancer." Annals of Medicine. 53:sup1 (2021): 28-29. DOI: 10.1080/07853890.2021.1896911.
Fernandes, Cláudio A., Alexei Yu. Karlovich, and Márcio Valente. "Invertibility of Fourier convolution operators with piecewise continuous symbols on Banach function spaces." Transactions of A. Razmadze Mathematical Institute. 175.1 (2021): 49-61.Website
G., Correia Viviana, Trovão Filipa, Pinheiro Benedita A., Brás Joana L. A., Silva Lisete M., Nunes Cláudia, Coimbra Manuel A., Liu Yan, Feizi Ten, Fontes Carlos M. G. A., Mulloy Barbara, Chai Wengang, Carvalho Ana Luísa, and Palma Angelina S. "Mapping Molecular Recognition of β1,3-1,4-Glucans by a Surface Glycan-Binding Protein from the Human Gut Symbiont Bacteroides ovatus." Microbiology SpectrumMicrobiology Spectrum (2021): e01826-21. AbstractWebsite

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Puértolas-Pascual, Eduardo, Miguel Marx, Octávio Mateus, André Saleiro, Alexandra E. Fernandes, João Marinheiro, Carla Tomás, and Simão Mateus. "A new plesiosaur from the Lower Jurassic of Portugal and the early radiation of Plesiosauroidea." Acta Palaeontologica Polonica. 66.2 (2021): 369-388. Abstracta_new_plesiosaur_from_the_lower_jurassic_of_portugal_and_the_early_radiation_of_plesiosauroidea.pdfWebsite

A new plesiosaur partial skeleton, comprising most of the trunk and including axial, limb, and girdle bones, was collected in the lower Sinemurian (Coimbra Formation) of Praia da Concha, near São Pedro de Moel in central west Portugal. The specimen represents a new genus and species, Plesiopharos moelensis gen. et sp. nov. Phylogenetic analysis places this taxon at the base of Plesiosauroidea. Its position is based on this exclusive combination of characters: presence of a straight preaxial margin of the radius; transverse processes of mid-dorsal vertebrae horizontally oriented; ilium with sub-circular cross section of the shaft and subequal anteroposterior expansion of the dorsal blade; straight proximal end of the humerus; and ventral surface of the humerus with an anteroposteriorly long shallow groove between the epipodial facets. In addition, the new taxon has the following autapomorphies: iliac blade with less expanded, rounded and convex anterior flank; highly developed ischial facet of the ilium; apex of the neural spine of the first pectoral vertebra inclined posterodorsally with a small rounded tip. This taxon represents the most complete and the oldest plesiosaur species in the Iberian Peninsula. It is also the most complete, best preserved, and oldest marine vertebrate in the region and testifies to the incursion of marine reptiles in the newly formed proto-Atlantic sea, prior to the Atlantic Ocean floor spreading in the Early Cretaceous.

Fernandes, Vítor H., M. M. Jesus, and B. Singha. "On orientation-preserving transformations of a chain." Communications in Algebra (DOI 10.1080/00927872.2020.1870996). 49.6 (2021): 2300-2325. AbstractWebsite

In this paper we introduce the notion of an orientation-preserving transformation on an arbitrary chain, as
a natural extension for infinite chains of the well known concept for finite chains introduced in 1998 by McAlister and, independently, in 1999 by Catarino and Higgins.
We consider the monoid POP(X) of all orientation-preserving partial transformations on a finite or infinite chain X and its submonoids OP(X) and POPI(X) of all orientation-preserving full transformations and of all orientation-preserving partial permutations on X, respectively.
The monoid PO(X) of all order-preserving partial transformations on X and its injective counterpart POI(X) are also considered.
We study the regularity and give descriptions of the Green's relations of the monoids POP(X), PO(X), OP(X), POPI(X) and POI(X).

Fernandes, V. H., M. M. Jesus, and B. Singha. "On orientation-preserving transformations of a chain." Communications in Algebra (2021): 1-26.
Vieira, Manuel V. C., Flora Ferreira, José Duque, and Rui Almeida. "On the packing process in a shoe manufacturer." Journal of the Operational Research Society. 72.4 (2021): 853-864.
Costa, S., M. Faias, P. Júdice, and P. Mota. "Panel data modeling of bank deposits." Annals of Finance. 17 (2021): 247-264. AbstractWebsite

Studying the dynamics of deposits is important for three reasons: first, it serves as an important component of liquidity stress testing; second, it is crucial to asset-liability management exercises and the allocation between liquid and illiquid assets; third, it is the support for a liquidity at risk (LaR) methodology.

Current models are based on AR(1) processes that often underestimate liquidity risk. Thus a bank relying on those models may face failure in an event of crisis. We propose a novel approach for modeling deposits, using panel data and a momentum term.

The model enables the simulation of a variety of deposit trajectories, including episodes of financial distress, showing much higher drawdowns and realistic liquidity at risk estimates, as well as density plots that present a wide range of possible values, corresponding to booms and financial crises.

Therefore, this methodology is more suitable for liquidity management at banks, as well as for conducting liquidity stress tests.

Dimitrova, I., Vítor H. Fernandes, J. Koppitz, and T. M. Quinteiro. "Partial Automorphisms and Injective Partial Endomorphisms of a Finite Undirected Path." Semigroup Forum. 103 (2021): 87-105. AbstractWebsite

In this paper, we study partial automorphisms and, more generally, injective partial endomorphisms of a finite undirected path from Semigroup Theory perspective. Our main objective is to give formulas for the ranks of the monoids IEnd(P_n) and PAut(P_n) of all injective partial endomorphisms and of all partial automorphisms of the undirected path P_n with n vertices. We also describe Green's relations of PAut(P_n) and IEnd(P_n) and calculate their cardinals.

Casimiro, Ana, and Susana Ferreira. "Principal Higgs Bundles and Schottky Representations." ISAAC 2019 (2021).
Rocha, H., E. Faggiano, A. Sacristan, and M. Santacruz-Rodríguez Professional development for the integration of technology in the teaching of Mathematics: in search of pragmatic theories - Desenvolvimento profissional para a integração da tecnologia no ensino da Matemática: em busca de teorias pragmáticas. XXXI Seminário de Investigação em Educação Matemática. Santarém: APM, 2021. Abstractsiem_2021.pdf

This paper presents part of a study that aimed to make more explicit the pragmatic theories that inform the design of professional development programs with an emphasis on the integration of digital technologies in the practices of mathematics teachers. The analysis carried out was based on a set of projects considered representative and implemented in four countries – Colombia, Italy, Mexico and Portugal. Based on this analysis, we identify relevant elements (e.g., similarities and differences, barriers and opportunities) and develop recommendations to be taken into account in the design of future professional development programs. In this process, we identified a set of aspects and sub-aspects, as well as several interconnections between them, which emerged in relation to five main themes and allowed us to reveal our pragmatic theories. Thus, this work provides a framework to support the design of future projects for the professional development of mathematics teachers regarding the use of digital technology.

Ribau, A. M., L. L. Ferrás, M. L. Morgado, M. Rebelo, M. A. Alves, F. T. Pinho, and A. M. Afonso. "A study on mixed electro-osmotic/pressure-driven microchannel flows of a generalised Phan-Thien–Tanner fluid." Journal of Engineering Mathematics . 127.7 (2021).
Krings, Bettina-Johanna, António B. Moniz, and Philipp Frey. "Technology as enabler of the automation of work? Current societal challenges for a future perspective of work." Revista Brasileira de Sociologia. 9.21 (2021): 206-229. Abstract806-1705-1-pb_revbrassociologia.pdfWebsite

Due to the innovative possibilities of digital technologies, the issue of increasing automation is once again on the agenda – and not only in the industry, but also in other branches and sectors of contemporary societies. Although public and scientific discussions about automation seem to raise relevant questions of the “old” debate, such as the replacement of human labor by introducing new technologies, the authors focus here on the new contextual quality of these questions. The debate should rethink the relationship between technology and work with regard to quantitative and qualitative changes in work. In this article, our example will be the introduction of automation in industry, which has been reflected in the widely recognized study by Frey and Osborne in 2013. They estimated the expected impacts of future computerization on US labor market outcomes as very high, specifically regarding the number of jobs at risk. Surprisingly, this study was the starting point of an intensive international debate on the impact of technologies on the future of work and the role of technological change in working environments. Thus, according to the authors, “old” questions remain important, but they should be reinterpreted for “new” societal demands and expectations of future models of work.

Faggiano, E., H. Rocha, A. Sacristan, and M. Santacruz-Rodríguez. "Towards pragmatic theories to underpin the design of teacher professional development concerning technology use in school mathematics." Mathematics Education in the Digital Age: Learning, Practice and Theory . Eds. A. Donevska-Todorova, E. Faggiano, J. Trgalova, H. - G. Weigand, and A. Clark-Wilson. Routledge, 2021. 42-68. Abstract

This chapter aims to make more explicit the grounded or ‘pragmatic theories’ that inform the design of mathematics teachers’ professional development (PD) to exploit technological affordances. It uses aspects of some representative projects that took place in four countries (Colombia, Italy, Mexico, and Portugal) to illustrate lessons learned (e.g., similarities and differences, barriers and opportunities) and provide important insights to inform future PD implementations. To do this, we have identified a set of aspects (and sub-aspects) that emerged in relation to five major themes and reveal our ‘pragmatic theories’ alongside a consideration of the interconnections between these aspects. Our contribution offers a methodological frame to support future PD designs for teachers of mathematics concerning digital technology uses.

Fernandes, Vítor H. "The Vagner-Preston representation of a block-group." Southeast Asian Bull. Math.. 45.6 (2021): 805-812. AbstractWebsite

In this short note we construct an extension of the Vagner-Preston representation for block-groups and show that its kernel is the largest congruence that separates regular elements.

Oliveira, R. D., A. Mouquinho, P. Centeno, M. Alexandre, S. Haque, R. Martins, E. Fortunato, H. Águas, and MJ Mendes. "Colloidal lithography for photovoltaics: An attractive route for light management." Nanomaterials. 11 (2021). AbstractWebsite
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Grey, P., M. Chapa, M. Alexandre, T. Mateus, E. Fortunato, R. Martins, MJ Mendes, and L. Pereira. "Combining Soft with Hard Condensed Matter for Circular Polarized Light Sensing and Logic Operations." Advanced Optical Materials. 9 (2021). AbstractWebsite
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Miranda, R., E. Babilio, N. Singh, F. Santos, and F. Fraternali. "Computational modeling of the mechanics of energy harvesters based on tensegrity solar faÇades." World Congress in Computational Mechanics and ECCOMAS Congress. Vol. 900. 2021. Abstract
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