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2024
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.

Farham, Babak, Flávio Craveiro, António Brandão Moniz, and Andreas Seebacher Impact of Urban Morphology on Energy Consumption: An Approach Towards Sustainability. Proceedings of the 3rd International Conference on Water Energy Food and Sustainability (ICoWEFS 2023). Cham: Springer Proceedings in Earth and Environmental Sciences, 2024. Abstract

Political and economic crises and issues such as global warming, decreased fossil fuel reserves, environmental pollutions and acid rains are just some of the problems caused by improper energy consumption. Energy efficiency optimization with the right policy and definition of accurate scientific methods proven in energy consumption includes planning, enforcement, organizing permanent control, and continuously reviewing technology upgrades. Additionally, developing legal solutions to implement these programs prevents the destruction and waste of energy resources and reduces the side effects of improper energy consumption. The shape of the city and its components can affect the city’s quality and its spaces, as well as the air quality change, creating a particular climate in their area, causing phenomena such as heat islands, dust, rain, albedo, atmospheric inversion, and some others. By making changes in the shape of the city, both on a large scale and a micro-scale, atmospheric currents and, consequently, air quality in cities can be improved. Urban morphological indicators, including building height, building type, occupancy level, segmentation, block size, block shape, density, and urban green, can affect the weather and climate conditions outside and inside the building and, thus, the energy demand in the areas. By creating effective reforms in the model of configuration of the urban regions, including the pattern of land fragmentation, the physical characteristics of buildings, the network of passages and open spaces, it is possible to increase the energy efficiency of buildings in the long term in the regional(synoptic) climatic conditions of the city and the neighbourhood.

Candeias, Marta, and António B. Moniz. "Impacto da Inteligência Artificial no emprego: o caso português." As novas infraestruturas produtivas: Digitalização do trabalho, e-logística e indústria 4.0. Eds. Ricardo Festi, and Jörg Nowak. São Paulo: Boitempo, 2024. 121-142.
Giglione, S., E. Faggiano, and H. Rocha Investigating the impact of technology integration on Italian and Portuguese teachers’ perspectives concerning standardized assessment. MEDA – Mathematics Education at the Digital Age. Bari, Italy: ERME, 2024.
Dimitrova, I., Vítor H. Fernandes, J. Koppitz, and T. M. Quinteiro. "On monoids of endomorphisms of a cycle graph." Mathematica Slovaca (DOI 10.1515/ms-2024-0078; Online 15 October 2024). 74.5 (2024): 1071-1088. AbstractWebsite

In this paper we consider endomorphisms of an undirected cycle graph from Semigroup Theory perspective. Our main aim is to present a process to determine sets of generators with minimal cardinality for the monoids $wEnd(C_n)$ and $End(C_n)$ of all weak endomorphisms and all endomorphisms of an undirected cycle graph $C_n$ with $n$ vertices. We also describe Green's relations and regularity of these monoids and calculate their cardinalities.

Dimitrova, I., Vítor H. Fernandes, and J. Koppitz. "On partial endomorphisms of a star graph." Quaestiones Mathematicae (DOI 10.2989/16073606.2024.2374796; Online 31 July 2024). 47.12 (2024): 2485-2505. AbstractWebsite

In this paper we consider the monoids of all partial endomorphisms, of all partial weak endomorphisms, of all injective partial endomorphisms, of all partial strong endomorphisms and of all partial strong weak endomorphisms of a star graph with a finite number of vertices. Our main objective is to determine their ranks. We also describe their Green's relations, calculate their cardinalities and study their regularity.

Fernandes, Vítor H. "On the cyclic inverse monoid on a finite set." Asian-European Journal of Mathematics (DOI 10.1142/S1793557124500177; Online 6 Mar 2024). 17.2 (2024): 2450017 (16 pages). AbstractWebsite

In this paper we study the cyclic inverse monoid CI_n on a set Ω_n with n elements, i.e. the inverse submonoid of the symmetric inverse monoid on Ω_n consisting of all restrictions of the elements of a cyclic subgroup of order n acting cyclically on Ω_n. We show that CI_n has rank 2 (for n⩾2) and n⋅2^n−n+1 elements. Moreover, we give presentations of CI_n on n+1 generators and (n^2+3n+4)/2 relations and on 2 generators and (n^2−n+6)/2 relations. We also consider the remarkable inverse submonoid OCI_n of CI_n constituted by all its order-preserving transformations. We show that OCI_n has rank n and 3⋅2^n−2n−1 elements. Furthermore, we exhibit presentations of OCI_n on n+2 generators and (n^2+3n+8)/2 relations and on n generators and (n^2+3n)/2 relations.

Fernandes, Vítor H. "On the monoid of order-preserving transformations of a finite chain whose ranges are intervals." Semigroup Forum (DOI 10.1007/s00233-024-10466-2; Online 19 Aug 2024). 109.2 (2024): 336-346. AbstractWebsite

In this note we give a presentation for the monoid IO_n of all order-preserving transformations of a n-chain whose ranges are intervals. We also consider the submonoid IO_n^- of IO_n consisting of order-decreasing transformations, for which we determine the cardinality, the rank and a presentation.

Fernandes, Vítor H. "On the monoid of partial isometries of a wheel graph." Asian-European Journal of Mathematics (DOI 10.1142/S1793557123502388; Online 16 Dec 2023). 17.1 (2024): 2350238 (18 pages). AbstractWebsite

In this paper, we consider the monoid DPW_n of all partial isometries of a wheel graph W_n with n+1 vertices. Our main objective is to determine the rank of DPW_n. In the process, we also compute the ranks of three notable subsemigroups of DPW_n. We also describe Green's relations of DPW_n and of its three considered subsemigroups.

Dimitrova, I., Vítor H. Fernandes, J. Koppitz, and T. M. Quinteiro. "On three submonoids of the dihedral inverse monoid on a finite set." Bulletin of the Malaysian Mathematical Sciences Society (DOI 10.1007/s40840-023-01620-0; Online 11 Dec 2023). 47 (2024): 27. AbstractWebsite

In this paper we consider three submonoids of the dihedral inverse monoid DI_n, namely its submonoids OPDI_n, MDI_n and ODI_n of all orientation-preserving, monotone and order-preserving transformations, respectively. For each of these three monoids, we compute the cardinal, give descriptions of Green's relations and determine the rank.

Sacristán, A., E. Faggiano, M. Santacruz-Rodríguez, and H. Rocha. "Policies and implementations for technology use in mathematics education: perspectives from around the world." Handbook of digital resources in mathematics education. Springer, 2024. 1-35. Abstract

In this chapter, we examine the role of policies and other factors affecting digital technology (DT) integration in mathematics education. In particular, we develop a cross-national analysis of the impact on DT implementation in four countries: two countries in Europe (Italy and Portugal) and two countries in Latin America (Colombia and Mexico). We analyze the role that policies, political changes, reforms, curricula, educational organization and systems, sociocultural aspects, and teachers’ training, knowledge, and beliefs play toward possible DT implementations. We observe that there is a discourse in policies to promote digital technologies’ use, but in practice the availability and integration of such resources in mathematics classrooms is still scarce. We also note that the efforts done during the pandemic did not change this, promoting general ICT use, rather than DT resources that might enhance mathematics teaching and learning.

Rotatori, Filippo Maria, Lucrezia Ferrari, Cristina Sequero, Bruno Camilo, Octávio Mateus, and Miguel Moreno-Azanza. "An unexpected early-diverging iguanodontian dinosaur (Ornithischia, Ornithopoda) from the Upper Jurassic of Portugal." Journal of Vertebrate Paleontology (2024): e2310066. Abstractrotatori_et_al_2024_an_unexpected_iguanodontian_dinosaur__ornithischia__ornithopoda__portugal.pdfWebsite

Iguanodontia is a diverse clade of herbivorous ornithischian dinosaurs that were speciose and abundant during the Jurassic and Cretaceous. Although the monophyly of Iguanodontia is well supported, their internal relationships have sparked heated debate due to several phylogenetic paradigm shifts. Late Jurassic basally branching iguanodontians in particular are not well understood in terms of their systematic affinities and evolutionary relevance. Their fossil record in Europe is meager compared with North America, with only a few species currently recognized. Two taxa are currently known from the Upper Jurassic of England, the basally branching styracosternan Cumnoria prestwichii and the putative dryosaurid Callovosaurus leedsi. In the Upper Jurassic of Portugal, the styracosternan Draconyx loureiroi and the dryosaurid Eousdryosaurus nanohallucis are presently the only described basally branching iguanodontians. Here we report a new species of early diverging iguanodontian from the Upper Jurassic Lourinhã Formation of western-central Portugal. The new species is clearly distinguished from all other coeval taxa by an exclusive combination of characters that include a tibia with a cnemial crest that is directed craniolaterally and a fibular condyle that is angled at 90° with respect to the proximal epiphysis, a fibula with symmetrical proximal margins, and a reduced metatarsal I. The phylogenetic relationships of the Lourinhã iguanodontian were explored using maximum parsimony and Bayesian inference. The two analyses recover the Lourinhã iguanodontian as an indeterminate dryomorphan, with more precise affinities precluded due to the current available material. Body size is estimated between 3 and 4 meters for the holotype specimen, adding to the diversity of small ornithopods already recognized in the paleoichnological record of the Lourinhã Formation. http://zoobank.org/urn:lsid:zoobank.org:pub:5F4D52D0-0F0B-4809-8561-BE58C7C97D45

Jacobs, Louis L., Stefan Schröder, Nair de Sousa, Richard Dixon, Edoardo Fiordalisi, Arthur Marechal, Octávio Mateus, Pedro Claude Nsungani, Michael J. Polcyn, Gustavo Couto Ramos do Pereira, Nathan Rochelle-Bates, Anne S. Schulp, Christopher R. Scotese, Ian Sharp, Carlos Gaudari Silvano, Roger Swart, and Diana P. Vineyard. "The Atlantic jigsaw puzzle and the geoheritage of Angola." Geological Society, London, Special Publications. 543 (2024): SP543-2022-301. AbstractWebsite

The jigsaw-puzzle fit of South America and Africa is an icon of plate tectonics and continental drift. Fieldwork in Angola since 2002 allows the correlation of onshore outcrops and offshore geophysical and well-core data in the context of rift, sag, salt, and post-salt drift phases of the opening of the central South Atlantic. These outcrops, ranging in age from >130 Ma to <71 Ma, record Early Cretaceous outpouring of the Etendeka-Paraná Large Igneous Province (Bero Volcanic Complex) and rifting, followed by continental carbonate and siliciclastic deposition (Tumbalunda Formation) during the sagging of the nascent central South Atlantic basin. By the Aptian, evaporation of sea water resulted in thick salt deposits (Bambata Formation), terminated by sea floor spreading. The Equatorial Atlantic Gateway began opening by the early Late Cretaceous (100 Ma) and allowed flow of currents between the North and South Atlantic, creating environmental conditions that heralded the introduction of marine reptiles. These dramatic outcrops are a unique element of geoheritage because they arguably comprise the most complete terrestrially exposed geological record of the puzzle-like icon of continental drift.

Viñas-Ospino, Adriana, Ana Rita Jesus, Alexandre Paiva, Maria J. Esteve, Ana Frígola, Jesús Blesa, and Daniel López-Malo. "Comparison of green solvents for the revalorization of orange by-products: Carotenoid extraction and in vitro antioxidant activity." Food Chemistry. 442 (2024): 138530. AbstractWebsite

Orange peels contain a considerable number of bioactive compounds such as carotenoids, that can be used as ingredients in high-value products. The aim of this study was to compare orange peel extracts obtained with different green solvents (vegetable oils, fatty acids, and deep eutectic solvents (DES)). In addition, the chemical characterization of a new hydrophobic DES formed by octanoic acid and l-proline (C8:Pro) was performed. The extracts were compared in terms of carotenoid extraction, antioxidant activity by three methods, color, and environmental impact. The results confirmed that the mixture of C8:Pro is a DES and showed the highest carotenoid extraction (46.01 µg/g) compared to hexane (39.28 µg/g). The antioxidant activity was also the highest in C8:Pro (2438.8 µM TE/mL). Finally, two assessment models were used to evaluate the greenness and sustainability of the proposed extractions. These results demonstrated the potential use of orange peels in the circular economy and industry.

Franco, Miguel, Asal Kiazadeh, Jonas Deuermeier, S. Lanceros-Méndez, Rodrigo Martins, and Emanuel Carlos. "Inkjet printed IGZO memristors with volatile and non-volatile switching." Scientific Reports. 14 (2024). Abstract

Solution-based memristors deposited by inkjet printing technique have a strong technological potential based on their scalability, low cost, environmentally friendlier processing by being an efficient technique with minimal material waste. Indium-gallium-zinc oxide (IGZO), an oxide semiconductor material, shows promising resistive switching properties. In this work, a printed Ag/IGZO/ITO memristor has been fabricated. The IGZO thickness influences both memory window and switching voltage of the devices. The devices show both volatile counter8wise (c8w) and non-volatile 8wise (8w) switching at low operating voltage. The 8w switching has a SET and RESET voltage lower than 2 V and − 5 V, respectively, a retention up to 105 s and a memory window up to 100, whereas the c8w switching shows volatile characteristics with a low threshold voltage (Vth < − 0.65 V) and a characteristic time (τ) of 0.75 ± 0.12 ms when a single pulse of − 0.65 V with width of 0.1 ms is applied. The characteristic time alters depending on the number of pulses. These volatile characteristics allowed them to be tested on different 4-bit pulse sequences, as an initial proof of concept for temporal signal processing applications.

Panigrahi, S., S. Jana, T. Calmeiro, E. Fortunato, MJ Mendes, and R. Martins. "MXene-Enhanced Nanoscale Photoconduction in Perovskite Solar Cells Revealed by Conductive Atomic Force Microscopy." ACS Applied Materials and Interfaces. 16 (2024): 1930-1940. AbstractWebsite
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Haque, S., M. Alexandre, A. T. Vicente, K. Li, C. S. Schuster, S. Yang, H. Águas, R. Martins, R. A. S. Ferreira, and MJ Mendes. "Photon shifting and trapping in perovskite solar cells for improved efficiency and stability." Light: Science and Applications. 13 (2024). AbstractWebsite
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dos Santos, FA, A. Favata, A. Micheletti, R. Paroni, and M. Picchi Scardaoni. "Programming quadric metasurfaces via infinitesimal origami maps of monohedral hexagonal tessellations: Part i." Proceedings of the Royal Society A: Mathematical, Physical and Engineering Sciences. 480 (2024). AbstractWebsite
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dos Santos, FA, A. Favata, A. Micheletti, R. Paroni, and M. P. Scardaoni. "Programming quadric metasurfaces via infinitesimal origami maps of monohedral hexagonal tessellations: Part II." Proceedings of the Royal Society A: Mathematical, Physical and Engineering Sciences. 480 (2024). AbstractWebsite
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dos Santos, FA, A. Favata, A. Micheletti, R. Paroni, and M. P. Scardaoni. "Tiled Plates with One Degree of Freedom." Lecture Notes in Civil Engineering. 437 (2024): 693-698. AbstractWebsite
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Alexandre, M., H. Águas, E. Fortunato, R. Martins, and MJ Mendes. "Understanding the Potential of Light Absorption in Dots-in-Host Semiconductors." ACS Photonics (2024). AbstractWebsite
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2023
L, Guerra-Guimarães, Jéfyne Carrera, Marina Rosário do Santos, Carla Pinheiro, Manzur-E-Mohsina Ferdous, Inês Diniz, Andreia Loureiro, and et al. "Assessment of carbon metabolism of Coffee Kawisari hybrid challenged by Hemileia vastatrix, the causal agent of Coffee Leaf Rust. (Oral Presentation - LGG speaker)." Thessaloniki 2023. 9. Abstract
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Coelho, Beatriz J., Joana V. Pinto, Jorge Martins, Ana Rovisco, Pedro Barquinha, Elvira Fortunato, Pedro V. Baptista, Rodrigo Martins, and Rui Igreja. "{Parylene C as a Multipurpose Material for Electronics and Microfluidics}." Polymers. 15 (2023): 2277. AbstractWebsite

Poly(p-xylylene) derivatives, widely known as Parylenes, have been considerably adopted by the scientific community for several applications, ranging from simple passive coatings to active device components. Here, we explore the thermal, structural, and electrical properties of Parylene C, and further present a variety of electronic devices featuring this polymer: transistors, capacitors, and digital microfluidic (DMF) devices. We evaluate transistors produced with Parylene C as a dielectric, substrate, and encapsulation layer, either semitransparent or fully transparent. Such transistors exhibit steep transfer curves and subthreshold slopes of 0.26 V/dec, negligible gate leak currents, and fair mobilities. Furthermore, we characterize MIM (metal–insulator–metal) structures with Parylene C as a dielectric and demonstrate the functionality of the polymer deposited in single and double layers under temperature and AC signal stimuli, mimicking the DMF stimuli. Applying temperature generally leads to a decrease in the capacitance of the dielectric layer, whereas applying an AC signal leads to an increase in said capacitance for double-layered Parylene C only. By applying the two stimuli, the capacitance seems to suffer from a balanced influence of both the separated stimuli. Lastly, we demonstrate that DMF devices with double-layered Parylene C allow for faster droplet motion and enable long nucleic acid amplification reactions.

Pinheiro, Carla, Giovanni Emiliani, Giovanni Marino, Ana S. Fortunato, Matthew Haworth, Anna De Carlo, Maria Manuela Chaves, Francesco Loreto, and Mauro Centritto. "Metabolic Background, Not Photosynthetic Physiology, Determines Drought and Drought Recovery Responses in C3 and C2 Moricandias." International Journal of Molecular Sciences. 24 (2023): 4094. AbstractWebsite
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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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