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Submitted
Mulenga, A., M. Faias, P. Mota, and J. P. Pina. "Exchange rate volatility: An asymmetric tale from Mozambique." (Submitted). Abstract

This paper inspects how risk is affected by news sign and size within - depreciation, appreciation, stability - distinct exchange rate trends, and by volatility model choice, taking on various asymmetric Generalized Autoregressive Conditional Heteroskedasticity models to daily Mozambique New Metical against South Africa Rand, MZN/ZAR, exchange rate over January 2010 - December 2014. Our results show that risk measurement
and asymmetry of shocks to volatility depend on exchange rate trend, being that estimating the full sample conceals the actual behavior, and model choice, specifically the degree of nonlinearity and persistence. In particular, we find that when positive/negative news type matches the sign of the exchange rate trend, risk increases by more. Interestingly, this means that in times of appreciation the good news turns out to be bad,
likely because they raise the fear of overvaluation, under monitoring in natural resource producers and exporting countries. The findings contribute to the growing concern on nonlinear economic policy design, exchange rate targeting and surely international trade and investment decisions, where an incorrect assessment exchange rate risk and asymmetry may lead to mispricing of assets, namely options, and eventual underestimation of
measures, as Value at Risk, relevant for Basel agreement.

Baptista, AC, E. Fortunato, R. Martins, J. P. Borges, and I. Ferreira. "Electrospun cellulose-based membranes for bioelectrochemical devices." (Submitted). Abstract
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In Press
2025
Karlovych, Oleksiy, and Eugene Shargorodsky. "The essential norms of Toeplitz operators with symbols in $C+H^\infty$ on weighted Hardy spaces are independent of the weights." Integral Equations and Operator Theory. 97 (2025): article 4.Website
Rotatori, Filippo Maria, Fernando Escaso, Bruno Camilo, Filippo Bertozzo, Elisabete Malafaia, Octávio Mateus, Pedro Mocho, Francisco Ortega, and Miguel Moreno-Azanza and. "Evidence of large-sized ankylopollexian dinosaurs (Ornithischia: Iguanodontia) in the Upper Jurassic of Portugal." Journal of Systematic Palaeontology. 23 (2025): 2470789. Abstractevidence_of_large-sized_ankylopollexian_dinosaurs__ornithischia__iguanodontia__in_the_upper_jurassic_of_portugal.pdfWebsite

The Upper Jurassic beds of the Lusitanian Basin in central Portugal yield diverse dinosaurian fauna, dated to the Kimmeridgian–Tithonian interval. Saurischian dinosaurs are, overall, more abundant than their ornithischian counterparts, in terms of both specimens collected and species recognized. Iguanodontians are so far represented by the styracosternan Draconyx loureiroi, the dryosaurid Eousdryosaurus nanohallucis and the enigmatic dryomorphan Hesperonyx martinhotomasorum. Here we aim to highlight the diversity of this clade in the Late Jurassic of Portugal, presenting evidence for yet another species of ankylopollexian iguanodontian dinosaur, represented by the specimen SHN.JJS.015, which is housed at the Sociedade de História Natural, Torres Vedras. Detailed comparisons rule out attribution to previously known taxa, and phylogenetic analyses that include SHN.JJS.015 indicate early-diverging ankylopollexian affinities for this specimen. As there is no robust diagnosis, we do not erect a new formal species for it at this stage. Nevertheless, this specimen represents a previously unreported taxon that highlights greater diversity than previously estimated among the iguanodontians of the Late Jurassic and highlights the importance of Europe in diversification and dispersal events of this clade. A series of smaller, isolated femora from the same sub-basin as SHN.JJS.015 may represent the same taxon, presenting evidence of thriving communities of ankylopollexians during the Kimmeridgian–Tithonian interval in Portugal.

2024
Mihali, Alin, Hugo B. Rebelo, and Corneliu Cismasiu. "Explosion consequences assessment in buildings with complex geometries." 19th International Symposium on Interaction of the Effects of Munitions with Structures. Bonn, Germany 2024.
Vieira, Tânia, Ana Margarida Rebelo, João Paulo Borges, Célia Henriques, and Jorge Carvalho Silva. "Electrospun Polycaprolactone Membranes Expanded with Chitosan Granules for Cell Infiltration." 16.4 (2024): 527. Abstract
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Hammami, Imen, Manuel Pedro Fernandes Graça, Sílvia Rodrigues Gavinho, Suresh Kumar Jakka, João Paulo Borges, Jorge Carvalho Silva, and Luís Cadillon Costa. "Exploring the Impact of Copper Oxide Substitution on Structure, Morphology, Bioactivity, and Electrical Properties of 45S5 Bioglass®." 9.4 (2024): 213. Abstract
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Li, De Biao, and Vítor H. Fernandes. "Endomorphisms of semigroups of monotone transformations." Journal of Algebra and its Applications (DOI 10.1142/S0219498824502244; Online 5 July 2023). 23.13 (2024): 2450224 (17 pages). AbstractWebsite

In this paper, we characterize the monoid of endomorphisms of the semigroup of all monotone full transformations of a finite chain, as well as the monoids of endomorphisms of the semigroup of all monotone partial transformations and of the semigroup of all monotone partial permutations of a finite chain.

2023
Pessanha, Sofia, Alexandre Veiga, Delfim Doutel, Fernanda Silva, João Silva, Patrícia M. Carvalho, Sofia Barbosa, José Paulo Santos, Ana Félix, and Jorge Machado. "Evaluation of the influence of the formalin fixation time on the elemental content of tissues measured with X-ray fluorescence." Spectrochimica Acta Part B: Atomic Spectroscopy. 205 (2023): 106704. AbstractWebsite
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Silva, A., C. Morgado, and F. Barbosa. "EPIK2 QUIZ: AN EXAMPLE OF EFFECTIVE COLLABORATIVE LEARNING ACTIVITY." Proceedings of 17th annual International Technology, Education and Development Conference. Valença 2023.
Silva, José Malanho, Linda Cerofolini, Ana Luísa Carvalho, Enrico Ravera, Marco Fragai, Giacomo Parigi, Anjos L. Macedo, Carlos F. G. C. Geraldes, and Claudio Luchinat. "Elucidating the concentration-dependent effects of thiocyanate binding to carbonic anhydrase." 244 (2023): 112222. AbstractWebsite

Many proteins naturally carry metal centers, with a large share of them being in the active sites of several enzymes. Paramagnetic effects are a powerful source of structural information and, therefore, if the native metal is paramagnetic, or it can be functionally substituted with a paramagnetic one, paramagnetic effects can be used to study the metal sites, as well as the overall structure of the protein. One notable example is cobalt(II) substitution for zinc(II) in carbonic anhydrase. In this manuscript we investigate the effects of sodium thiocyanate on the chemical environment of the metal ion of the human carbonic anhydrase II. The electron paramagnetic resonance (EPR) titration of the cobalt(II) protein with thiocyanate shows that the EPR spectrum changes from A-type to C-type on passing from 1:1 to 1:1000-fold ligand excess. This indicates the occurrence of a change in the electronic structure, which may reflect a sizable change in the metal coordination environment in turn caused by a modification of the frozen solvent glass. However, paramagnetic nuclear magnetic resonance (NMR) data indicate that the metal coordination cage remains unperturbed even in 1:1000-fold ligand excess. This result proves that the C-type EPR spectrum observed at large ligand concentration should be ascribed to the low temperature at which EPR measurements are performed, which impacts on the structure of the protein when it is destabilized by a high concentration of a chaotropic agent.

Gonçalves, Adriana, Beatriz T. Simões, Filipe V. Almeida, Susete N. Fernandes, Manuel Valente, Tânia Vieira, Célia Henriques, João Paulo Borges, and Paula I. P. Soares. "Engineering dual-stimuli responsive poly (vinyl alcohol) nanofibrous membranes for cancer treatment by magnetic hyperthermia." 145 (2023): 213275. Abstract
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Hammami, Imen, Sílvia Rodrigues Gavinho, Ana Sofia Pádua, Maria Carmo do Lança, João Paulo Borges, Jorge Carvalho Silva, Isabel Sá-Nogueira, Suresh Kumar Jakka, and Manuel Pedro Fernandes Graça. "Extensive investigation on the effect of niobium insertion on the physical and biological properties of 45S5 bioactive glass for dental implant." 24.6 (2023): 5244. Abstract
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Li, De Biao, and Vítor H. Fernandes. "Endomorphisms of semigroups of oriented transformations." Semigroup Forum (DOI 10.1007/s00233-022-10325-y; Online 2 Dec 2022). 106 (2023): 184-210. AbstractWebsite

In this paper, we characterize the monoid of endomorphisms of the semigroup of all oriented full transformations of a finite chain, as well as the monoid of endomorphisms of the semigroup of all oriented partial transformations and the monoid of endomorphisms of the semigroup of all oriented partial permutations of a finite chain. Characterizations of the monoids of endomorphisms of the subsemigroups of all orientation-preserving transformations of the three semigroups aforementioned are also given. In addition, we compute the number of endomorphisms of each of these six semigroups.

Coimbra, Rute, Miguel Moreno-Azanza, Lope Ezquerro, Carmen Nuñez-Lahuerta, José Manuel Gasca, Adrian Immenhauser, Octávio Mateus, and Fernando Rocha. "Evaluating and comparing geochemical sampling protocols in dinosaur eggshells: refining Cretaceous ecosystem research." Cretaceous Research (2023): 105632. Abstractsingle_file_coimbra_et_al._2023_cretresearch.pdfWebsite

The geochemical signatures of dinosaur eggshells represent well-established proxies in paleoenvironmental and paleobiological research. The variable sampling procedures reported in the literature, however, deserve attention. In order to evaluate the impact of different sampling methodologies on carbon and oxygen isotope and elemental concentrations, grinding was contrasted with drilling to extract powder samples from eggshell fragments collected at several locations. Eggshell data were further contrasted with surface materials, encasing matrix and compared with independent proxies using petrographic and elemental techniques. Iron and manganese elemental concentrations revealed an enrichment sequence depending on the sampling strategy for the same eggshell fragment. This pattern can be mistaken for a variable state of preservation. In contrast, carbon and oxygen isotope values exhibited only subtle differences and lacked clear trends. This suggests that isotope data are less susceptible to different methodological approaches. It is shown that drilling offers a wider range of possibilities compared to grinding (e.g., faster and less destructive). Additionally, drilled powder samples can confidently be used for elemental and isotope analysis, excluding contamination, thus providing a more accurate set of proxy data from eggshell archives.

Gomes, G., H. Rebelo, V. Lúcio, C. Cismasiu, and J. Mingote. "Experimental Research and Development on Blast Resistant Structures." Advances on Testing and Experimentation in Civil Engineering, Springer Tracts in Civil Engineering. Switzerland: Springer Nature, 2023. 1-20.
de Gomes, Gabriel Jesus, Valter José Guia da Lúcio, Corneliu Cismasiu, and José Luis Mingote. "Experimental Validation and Numerical Analysis of a High-Performance Blast Energy-Absorbing System for Building Structures." Buildings. 13.601 (2023): 1-20.
Hammami, Imen, Sílvia R. Gavinho, Ana Sofia Pádua, Maria Carmo do Lança, João Paulo Borges, and Jorge Carvalho Silva. "Extensive Investigation on the Effect of Niobium Insertion on the Physical and Biological Properties of 45S5 Bioactive Glass for Dental Implant." International Journal of Molecular Sciences. 24.6 (2023): 5244-5263.
Rodrigues, Alexandra P., Pedro M. P. Santos, João Pedro Veiga, Maria Helena Casimiro, and Luís M. Ferreira. "Electron Beam Irradiation on the Production of a Si- and Zr-Based Hybrid Material: A Study by FTIR and WDXRF." Materials. 16 (2023). AbstractWebsite

Sol-gel production of hybrid materials has, to some extent, revolutionised materials’ engineering and the way science and technology perceive the creation of new materials. Despite that, the method presents some limitations that are circumvented by radiation processing. Electron beam irradiation was used to promote synthesis of hybrid structures while using silanol-terminated PDMS, TEOS and TPOZ as precursors. Evaluation of the method’s performance was executed by gel fraction determination, WDXRF and FTIR-ATR. Results showed that, although there is some pre-irradiation reactivity between precursors, radiolysis induces scission on multiple sites of precursor’s structures, which induces hybrid network formation to a greater extent. Characterisation allowed determining electron beam irradiation to be effective in the creation of Si–O–Zr bonds, resulting in the production of a Class II hybrid material.

Bento Rebelo, H., B. Assunção, C. Bedon, and F. Amarante dos Santos. "Exploratory study on the use of bi-stable supports for the impact protection of point-fixed glazing systems." International Journal of Protective Structures (2023). AbstractWebsite
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