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2024
Curbera, Guillermo P., Oleksiy Karlovych, and Eugene Shargorodsky. "On the full range of Zippin and inclusion indices of rearrangement-invariant spaces." Revista de la Real Academia de Ciencias Exactas, Físicas y Naturales. Serie A. Matemáticas. 118 (2024): 93.Website
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.

Rocha, H., F. Viseu, and S. Matos. "Problem solving in a real-life context: an approach during the learning of inequalities." European Journal of Science and Mathematics Education. 12.1 (2024). AbstractWebsite

This study was conducted while 9th grade students learn to solve inequalities and seeks to understand their approach to solving problems with a real-life context. Specifically, the aim is to understand: (1) What are the main characteristics of the students’ approaches to the proposed problems? (2) What is the impact of the real context on the students’ resolutions? A qualitative and interpretative methodology is adopted, based on case studies, with data collected through documentary collection and audio recording of discussions between a pair of students while solving problems. The main conclusions suggest a trend to approach problems without establishing immediate connections with what was being done in the classroom, with students’ decisions being essentially guided by criteria of simplicity. The real context of the problems seems to have the potential to develop in students a more integrated mathematics, focused on understanding and not so much on the repetition of mechanical and meaning-independent procedures. The students’ familiarization with the context in question is one of the aspects highlighted by this study.

Rocha, H., and A. Babo. "Problem-solving and mathematical competence: a look to the relation during the study of Linear Programming." Thinking Skills and Creativity. 51 (2024): 1-14. AbstractWebsite

This study seeks reflection on the approaches of 11th grade students to Linear Programming problems, discussing the approaches taken at different moments of the teaching process. It aims to analyze:
How is the students’ mathematical competence characterized in relation to problemsolving;
What differences can be identified in the resolutions at different moments of the teaching and learning process.
We adopt a qualitative and interpretative methodology, analyzing the approaches of two pairs of students with different mathematical backgrounds. The analysis is guided by P´olya’s stages of solving a problem and aspects of the understanding of mathematical competence. The results show different approaches to the problems depending on the teaching moment and different competences. The mathematical background impacts the students’ success when they implement routine procedures, however it does not seem to determine the students’ competence to reason about a problem.

Candeias, Marta, and António B. Moniz. "Public policies for Industry 4.0: some lessons from the Portuguese case." International Journal of Automotive Technology and Management. 24.2 (2024): 144-168. Abstractcover.jpgWebsite

In Portugal, digital transition was structured with national public policies since 2003. In 2017, initiatives for the adoption of Industry 4.0 concepts are implemented in Portugal. We analysed the diffusion and implementation of these technologies, in Portugal. Some questions were raised: has the interplay between public policies, state agencies and industrial relations players in the process been articulated, as in Germany? What have been the effects of these technologies on workers and organisations? Are the public initiatives in place enough or more is needed? Qualitative and quantitative approaches were used to collect evidence on the main features and constraints of a public policy for Industry 4.0, based on the case study of the automotive sector in Portugal. Findings suggest the need to balance regulatory policies on data related risks, and investment policies towards education, training and organisational innovation are needed to complement technology development and adoption support.

Sahyoun, Vincent, Jelena Petronijevic, Alain Etienne, Bettina-Johanna Krings, António B. Moniz, and Ali Siadat. "The relation between cognitive and organizational factors in the production environment." IFAC PapersOnLine. 58.19 (2024): 1030-1035. Abstractcognitive_and_organizational_factors_ifac24.pdfarticle_ifac_2024.jpgWebsite

The adoption of I4.0’s technologies in the work cells accompanied by societal changes calls for new approaches to manage the current production systems. Nevertheless, the current models simulating the behavior of the work cells limit the representation of the operators to the average human, without regard for their individual characteristics, cognitive abilities or psychosocial state. The aim of this paper is to achieve two objectives: firstly, the authors propose a conceptual model for enhancing a human-centered production environment. Secondly, the paper summarizes how the literature characterizes the different dimensions of relations between cognitive and organizational factors. By integrating the collaborative, psychological, social, cognitive, organizational and system performance dimensions, the proposed model focuses on the relationships between these dimensions. Thus, operational models should be closer to the real production environment to improve the design choices of the manufacturing systems.

Karlovych, Oleksiy, and Eugene Shargorodsky. "A remark on piecewise linear interpolation of continuous Fourier multipliers." Tbilisi Analysis and PDE Seminar. Extended Abstracts of the 2020-2023 Seminar Talks. Eds. Rolnad Duduchava, Eugene Shargorodsky, and George Tephnadze. Cham: Birkhäuser, 2024. 99-107.
Karlovych, Oleksiy, and Eugene Shargorodsky. "A remark on Toeplitz and Laurent operators acting on l-p spaces with power weights." Linear Algebra and Applications. 697 (2024): 82-92.Website
Botelho, M. C., and H. Rocha The role of teachers’ knowledge and the use of different technologies in the classroom. MEDA – Mathematics Education at the Digital Age. Bari, Italy: ERME, 2024. Abstract2024_meda_botelho_rocha.pdf

The potential of technology to enhance the learning of mathematics is widely acknowledged. However, realizing this potential requires teachers to possess the knowledge to effectively integrate it into their teaching practices. This study aims to characterize the mathematics teacher's knowledge when using different technologies in teaching and learning. It also aims to study the existence of relationships between the specific domains of the Knowledge for Teaching Mathematics with Technology – KTMT and the integration of graphing calculator and Excel. The methodology adopted is qualitative with an interpretative approach, using a case study of Mathematics teacher in the 11th grade (16-17 years old) with extensive experience in the use of technology. This study shows that different KTMT knowledge is mobilized, according to the technology chosen and the specific characteristics of each of the technologies used influenced the teacher's pedagogical choices.

Chalub, Fabio A. C. C., Paulo Doutor, Paula Patrício, and Maria do Céu Soares. "Social vs. individual age-dependent costs of imperfect vaccination." Mathematical Biosciences. 375 (2024): 109259. Abstract

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Rocha, H. Teaching Mathematics with technology: a preliminary version of the Global Knowledge model - Ensinar Matemática com tecnologia: uma versão preliminar do modelo Global do Conhecimento. SIEM 2024. Caldas da Rainha: APM, 2024. Abstractsiem2024_hr.pdf

This study aims to discuss similarities and differences between knowledge models focusing on technology, developing the Global Model. This is not a new model, but rather a contribution to the articulation between different conceptual frameworks.

Este estudo visa discutir semelhanças e diferenças entre modelos de conhecimento com foco na tecnologia, desenvolvendo a partir destes o Modelo Global. Este não é um novo modelo, mas antes um contributo para a articulação entre diferentes quadros conceptuais.

Milàn, Jesper, and Octávio Mateus. "A Turiasaurian (Dinosauria, Sauropoda) Tooth from the Pliensbachian Hasle Formation of Bornholm, Denmark, Shows an Early Jurassic Origin of the Turiasauria." Diversity. 16 (2024). Abstractmilan__mateus_2023_diversity-16-00012.pdfWebsite

Turiasauria is a clade of basal sauropod dinosaurs hitherto only known from the Middle Jurassic (Bathonian) to the Lower Cretaceous (Valanginian). A new find of a shed tooth crown from the Lower Jurassic (Pliensbachian), Halse Formation of Bornholm, Denmark, is spoon-like, asymmetrical, and heart-shaped, which identifies the tooth as turiasaurian, pushing the origin of the Turiasauria some 17 My back into the Lower Jurassic. This suggests a North Pangean/Laurasian origin of the turiasaurian clade, which then, during the Middle to Late Jurassic, dispersed through Europe, India, and Africa, with their latest representatives found in the Early Cretaceous of England and North America. Furthermore, this is the first record of a sauropod from the Pliensbachian in Europe.

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. AbstractWebsite

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

Rocha, H. The use of the TPACK framework on research about teachers’ knowledge to teach with digital technology. MEDA – Mathematics Education at the Digital Age. Bari, Italy: ERME, 2024. Abstract2024_meda_rocha.pdf

The potential of digital technologies for teaching and learning mathematics is widely recognized and teachers’ knowledge is one of the elements impacting their integration. Several authors have intended to characterize the teachers’ knowledge required and developed several models, being TPACK one of these models. In this study, we seek to conduct a systematic review of the research on the integration of digital technologies by mathematics teachers based on the TPACK model. Specifically, we intend to answer the following research questions: (1) What are the main methodological options adopted? (2) How is the framework operationalized/used in the studies? The review was based on a search in the Scopus database and resulted in the identification of 10 relevant documents. The analysis suggests a prevalence of qualitative approaches, but a strong use of questionnaires; and an integration of the model with other frameworks, namely the developmental model of TPACK.

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.

Sarmento, Célia, Ana Rita C. Duarte, and Ana Rita Jesus. "Can (Natural) deep eutectic systems increase the efficacy of ocular therapeutics?" European Journal of Pharmaceutics and Biopharmaceutics. 198 (2024): 114276. AbstractWebsite

The eye is one of the most complex organs in the human body, with a unique anatomy and physiology, being divided into anterior and posterior segments. Ocular diseases can occur in both segments, but different diseases affect different segments. Glaucoma and cataracts affect the anterior segment, while macular degeneration and diabetic retinopathy occur in the posterior segment. The easiest approach to treat ocular diseases, especially in the anterior segment, is through the administration of topical eye drops, but this route presents many constraints, namely precorneal dynamic and static ocular barriers. On the other hand, the delivery of drugs to the posterior segment of the eye is far more challenging and is mainly performed by the intravitreal route. However, it can lead to severe complications such as retinal detachment, endophthalmitis, increased intraocular pressure and haemorrhage. The design of new drug delivery systems for the anterior segment is very challenging, but targeting the posterior one is even more difficult and little progress has been made. In this review we will discuss various strategies including the incorporation of additives in the formulations, such as viscosity, permeability, and solubility enhancers, namely based on Deep eutectic systems (DES). Natural deep eutectic systems (NADES) have emerged to solve several problems encountered in pharmaceutical industry, regarding the pharmacokinetic and pharmacodynamic properties of drugs. NADES can contribute to the design of advanced technologies for ocular therapeutics, including hydrogels and nanomaterials. Here in, we revise some applications of (NA)DES in the development of new drug delivery systems that can be translated into the ophthalmology field.

Coutinho, Mathilda L., João Pedro Veiga, Andreia Ruivo, Teresa Pereira da Silva, Silvia Bottura-Scardina, Maria Margarida R. A. Lima, Carlos Pereira, Ana Carvalho Dias, Luis Dias, Peter Vandenabeele, and José C. Roseiro. "Characterization of Tableware from Fábrica de Loiça de Sacavém—Linking Analytical and Documental Research." Minerals. 14 (2024). AbstractWebsite

Fábrica de Loiça de Sacavém (ca. 1858–1994) was among the first to produce white earthenware in Portugal, becoming one of the country’s leading ceramic manufacturers during the late 19th to early 20th centuries. Research on white earthenware has accompanied the growing interest in post-industrial archaeology but is still poorly explored compared to more ancient ceramic productions. This study focused on the ceramic body, glazes, and colourants of tableware produced by Fábrica de Loiça de Sacavém during the first 50 years of its activity (1859–1910). A multi-analytical approach was selected to investigate the chemical and mineralogical composition of the ceramic body, glaze, and pigments using optical microscopy, variable-pressure scanning electron microscope energy-dispersive X-ray spectroscopy (VP-SEM-EDS), μ-Raman spectroscopy, μ-X-ray Diffraction (μ-XRD), and reflectance spectroscopy (hyperspectral image analysis). The studied tableware was produced with a Ca-poor siliceous–aluminous white earthenware ceramic body covered with transparent alkali lead or lead borosilicate glaze, and most colourants were complex Cr-based pigments. These results are in agreement with the little documental evidence from this period found in the manufacturer’s archives.

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.

da Silva, Vicente M., and A. N. Antão. "Computational Upper- and Lower-Bound 3D Limit Analysis Using the Hoek–Brown Yield Criterion." International Journal of Geomechanics. 24 (2024): 04024036. AbstractWebsite

The Hoek–Brown failure criterion has been widely applied to predict the strength of rock masses, demonstrating its relevance in diverse geotechnical contexts. This paper presents a novel 3D numerical implementation of the Hoek–Brown criterion in a finite-element limit analysis code. The proposed formulation is unique in its ability to produce strict upper and lower bounds for 3D problems, providing more accurate and reliable predictions of failure mechanisms compared to previous formulations. The validity of the formulation is demonstrated through comparisons with known analytical solutions or other authors’ numerical solutions. Furthermore, the proposed numerical tool is used to determine the stability of shallow circular tunnels in rock masses, highlighting its practical applicability in engineering design.

Domingues, Luis, Ana Rita C. Duarte, and Ana Rita Jesus. "How Can Deep Eutectic Systems Promote Greener Processes in Medicinal Chemistry and Drug Discovery?" Pharmaceuticals. 17 (2024). AbstractWebsite

Chemists in the medicinal chemistry field are constantly searching for alternatives towards more sustainable and eco-friendly processes for the design and synthesis of drug candidates. The pharmaceutical industry is one of the most polluting industries, having a high E-factor, which is driving the adoption of more sustainable processes not only for new drug candidates, but also in the production of well-established active pharmaceutical ingredients. Deep eutectic systems (DESs) have emerged as a greener alternative to ionic liquids, and their potential to substitute traditional organic solvents in drug discovery has raised interest among scientists. With the use of DESs as alternative solvents, the processes become more attractive in terms of eco-friendliness and recyclability. Furthermore, they might be more effective through making the process simpler, faster, and with maximum efficiency. This review will be focused on the role and application of deep eutectic systems in drug discovery, using biocatalytic processes and traditional organic chemical reactions, as new environmentally benign alternative solvents. Furthermore, herein we also show that DESs, if used in the pharmaceutical industry, may have a significant effect on lowering production costs and decreasing the impact of this industry on the quality of the environment.

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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