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2022
Firmino, Rita, Emanuel Carlos, Joana Vaz Pinto, Jonas Deuermeier, Rodrigo Martins, Elvira Fortunato, Pedro Barquinha, and Rita Branquinho. "{Solution Combustion Synthesis of Hafnium-Doped Indium Oxide Thin Films for Transparent Conductors}." Nanomaterials. 12 (2022): 2167. AbstractWebsite

{\textless}p{\textgreater}Indium oxide (In2O3)-based transparent conducting oxides (TCOs) have been widely used and studied for a variety of applications, such as optoelectronic devices. However, some of the more promising dopants (zirconium, hafnium, and tantalum) for this oxide have not received much attention, as studies have mainly focused on tin and zinc, and even fewer have been explored by solution processes. This work focuses on developing solution-combustion-processed hafnium (Hf)-doped In2O3 thin films and evaluating different annealing parameters on TCO's properties using a low environmental impact solvent. Optimized TCOs were achieved for 0.5 M{%} Hf-doped In2O3 when produced at 400 °C, showing high transparency in the visible range of the spectrum, a bulk resistivity of 5.73 × 10−2 $Ømega$.cm, a mobility of 6.65 cm2/V.s, and a carrier concentration of 1.72 × 1019 cm−3. Then, these results were improved by using rapid thermal annealing (RTA) for 10 min at 600 °C, reaching a bulk resistivity of 3.95 × 10 −3 $Ømega$.cm, a mobility of 21 cm2/V.s, and a carrier concentration of 7.98 × 1019 cm−3, in air. The present work brings solution-based TCOs a step closer to low-cost optoelectronic applications.{\textless}/p{\textgreater}

Madeira, Ricardo MD, Tânia Vieira, Jorge C. Silva, Ivone R. Oliveira, João P. Borges, M. M. R. A. Lima, and Carmo M. Lança Piezoelectric Calcium Modified Barium Titanate for Bone Regeneration. Vol. 8. Materials Proceedings 2022, Vol. 8, Page 121, 8. Basel Switzerland: Multidisciplinary Digital Publishing Institute, 2022. Abstract

Solid state reaction was used to produced barium titanate modified with calcium (BCT) showing the presence of the piezoelectric tetragonal phase after sintering at 1350 °C. Bioglass 45S5 (BG) was synthetized by sol-gel route. From these two materials and commercial hydroxyapatite (HAp) were obtained composites. The BG produced showed some cytotoxic character that was weakened by passivation. All other materials were non-cytotoxic. Contact polarization at constant temperature was chosen composites polarization. Electric/dielectric properties were evaluated by thermally stimulated depolarization currents (TSDC). The material showed bioactivity with the composite with BCT/BG/HAp 90/5/5 (wt%) showing increased bioactivity. In vitro test showed high proliferation rates for the composites.

Mateus, Ayana, and Frederico Caeiro. "Improved Shape Parameter Estimation for the Three-Parameter Log-Logistic Distribution." Computational and Mathematical Methods. 2022 (2022): 1-13. AbstractWebsite
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Amaro, P., A. Adamczak, Abdou M. Ahmed, L. Affolter, F. D. Amaro, P. Carvalho, T. L. Chen, L. M. P. Fernandes, M. Ferro, D. Goeldi, T. Graf, M. Guerra, T. W. Hänsch, C. A. O. Henriques, Y. C. Huang, P. Indelicato, O. Kara, K. Kirch, A. Knecht, F. Kottmann, Y. W. Liu, J. Machado, M. Marszalek, R. D. P. Mano, C. M. B. Monteiro, F. Nez, J. Nuber, A. Ouf, N. Paul, R. Pohl, E. Rapisarda, J. M. F. dos Santos, J. P. Santos, P. A. O. C. Silva, L. Sinkunaite, J. T. Shy, K. Schuhmann, S. Rajamohanan, A. Soter, L. Sustelo, D. Taqqu, L. B. Wang, F. Wauters, P. Yzombard, M. Zeyen, and A. Antognini. "Laser excitation of the 1s-hyperfine transition in muonic hydrogen." SciPost Physics. 13 (2022). Abstract

The CREMA collaboration is pursuing a measurement of the ground-state hyperfine splitting (HFS) in muonic hydrogen (μp) with 1 ppm accuracy by means of pulsed laser spectroscopy to determine the two-photon-exchange contribution with 2×10-4 relative accuracy. In the proposed experiment, the μp atom undergoes a laser excitation from the singlet hyperfine state to the triplet hyperfine state, then is quenched back to the singlet state by an inelastic collision with a H2 molecule. The resulting increase of kinetic energy after the collisional deexcitation is used as a signature of a successful laser transition between hyperfine states. In this paper, we calculate the combined probability that a μp atom initially in the singlet hyperfine state undergoes a laser excitation to the triplet state followed by a collisional-induced deexcitation back to the singlet state. This combined probability has been computed using the optical Bloch equations including the inelastic and elastic collisions. Omitting the decoherence effects caused by the laser bandwidth and collisions would overestimate the transition probability by more than a factor of two in the experimental conditions. Moreover, we also account for Doppler effects and provide the matrix element, the saturation fluence, the elastic and inelastic collision rates for the singlet and triplet states, and the resonance linewidth. This calculation thus quantifies one of the key unknowns of the HFS experiment, leading to a precise definition of the requirements for the laser system and to an optimization of the hydrogen gas target where μp is formed and the laser spectroscopy will occur.

Oliveira, Tiago, Pedro Matias, and Corneliu Cismasiu. "Comportamento de painéis de vidro laminado à ação de explosões - Geração de curvas Pressão-Impulso." PROTEDES2022. Região Sul da Ordem dos Engenheiros, Lisboa 2022.
Lopes, Tiago, Carmen Morgado, and Fernanda Barbosa. "Gait Monitor and Analyzer (GMA): a Wearable Sensor-based Gait Analysis System." Proceedings of International Conference on Pervasive Computing and Communications Workshops and other Affiliated Events. Italy 2022.
Cardoso, João, Patrícia Almeida, Gonçalo Catatão, Guilherme Cândida, Frederico Páscoa, Daniela Silva, Carla Machado, João P. Borges, and Alexandre Velhinho. "Designing Structural Metamaterials." 8.1 (2022): 55. Abstract
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Gonçalves, Adriana, Joana Matos, Raquel Cabrita, Inês Rodrigues, João Paulo Borges, and Paula I. P. Soares. "Development of Magnetic Nanofibrous Membranes for Localized Solid Cancer Treatment." 8.1 (2022): 119. Abstract
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Morelli, Sabrina, Antonella Piscioneri, Simona Salerno, Ricardo Matos, Paula I. P. Soares, Jorge Carvalho Silva, João Paulo Borges, and Loredana De Bartolo. "Hollow Fiber and Nanofiber Membranes in Bioartificial Organs and Tissue Engineering." Hollow Fibers and Nanofibers in Membrane Science. Jenny Stanford Publishing, 2022. 409-460. Abstract
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Matos, Ricardo JR, Paula I. P. Soares, Jorge Carvalho Silva, and João Paulo Borges. "Magnetic Bioactive Glass-Based 3D Systems for Bone Cancer Therapy and Regeneration." 8.1 (2022): 18. Abstract
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Conti, Simone, Emanuel Tschopp, Octávio Mateus, Andrea Zanoni, Pierangelo Masarati, and Giuseppe Sala. "Multibody analysis and soft tissue strength refute supersonic dinosaur tail." Scientific Reports. 12.1 (2022): 19245. Abstractconti_et_al_2022._multibody_analysis_and_soft_tissue_strength_refute_supersonic_dinosaur_tail.pdfWebsite

Sauropod dinosaurs are well known for their massive sizes and long necks and tails. Among sauropods, flagellicaudatan dinosaurs are characterized by extreme tail elongation, which has led to hypotheses regarding tail function, often compared to a whip. Here, we analyse the dynamics of motion of a 3D model of an apatosaurine flagellicaudatan tail using multibody simulation and quantify the stress-bearing capabilities of the associated soft tissues. Such an elongated and slender structure would allow achieving tip velocities in the order of 30 m/s, or 100 km/h, far slower than the speed of sound, due to the combined effect of friction of the musculature and articulations, as well as aerodynamic drag. The material properties of the skin, tendons, and ligaments also support such evidence, proving that in life, the tail would not have withstood the stresses imposed by travelling at the speed of sound, irrespective of the conjectural ‘popper’, a hypothetical soft tissue structure analogue to the terminal portion of a bullwhip able to surpass the speed of sound.

Máximo, Patrícia, Miriam Colaço, Sofia R. Pauleta, Paulo J. Costa, Uwe Pischel, Jorge A. Parola, and Nuno Basílio. "Photomodulation of ultrastable host–guest complexes in water and their application in light-controlled steroid release." Organic Chemistry Frontiers. 9.16 (2022): 4238-4249. AbstractWebsite

The cucurbit[8]uril (CB8) synthetic receptor is shown to form high-affinity host–guest complexes with dicationic dithienylethene (DTE) photoswitches in water. ITC experiments combined with computational studies suggest that the formation of the inclusion complexes is mainly driven by a combination of hydrophobic effects, ion–dipole, hydrogen- and chalcogen-bonding interactions. The binding affinities were observed to be much higher for the DTE closed isomers, reaching values in the picomolar range (up to 1011 M−1) while the open isomers display up to 10 000-fold lower affinities, setting ideal conditions for the development of robust photoswitchable host–guest complexes. The light-responsive affinity of these photoswitches toward CB8 was explored to control the encapsulation and release of nanomolar affinity steroids via competitive guest replacement.

Madeira, Ricardo MD, Tânia Vieira, Jorge C. Silva, Ivone R. Oliveira, João P. Borges, Margarida RA M. Lima, and Carmo M. Lança. "Piezoelectric Calcium Modified Barium Titanate for Bone Regeneration." 8.1 (2022): 121. Abstract
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Pires, Laura S., Diogo Melo, João P. Borges, and Célia R. Henriques. "PLA Electrospun Fibres Coated with PEDOT by Vapor-Phase Polymerization for Neural Regeneration." 8.1 (2022): 100. Abstract
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Guillaume, Alexandre R. D., Carlos Natário, Octávio Mateus, and Miguel Moreno-Azanza. "Plasticity in the morphology of the fused frontals of Albanerpetontidae (Lissamphibia; Allocaudata)." Historical Biology (2022): 1-18. Abstractplasticity_in_the_morphology_of_the_fused_frontals_of_albanerpetontidae_lissamphibia_allocaudata.pdfWebsite

ABSTRACTAlbanerpetontidae form an enigmatic extinct group of lissamphibians, ranging from the early Bathonian to the early Pleistocene. The Upper Jurassic outcrops of Portugal yield a large collection of material, suitable for addressing the intraspecific variation in and diagnostic potential of the characteristic fused frontals. We revise 58 specimens from the Guimarota beds of the Kimmeridgian Alcobaça Formation and describe 62 new frontal bones from the Kimmeridgian ? Tithonian Lourinh? Formation. Smaller specimens exhibit a vermicular dorsal ornamentation, while it is polygonal in larger specimens and other albanerpetontids. Compared to small specimens, larger specimens display: (1) larger ventrolateral crests extending posteriorly after the parietal margin; (2) a relatively shorter internasal process; (3) a frontal width across posterior edges relatively smaller; and (4) a ventromedian crest less pronounced. Morphometric analyses suggest a single species with different ontogenetic stages. Specimens are attributed to aff. Celtedens sp., based on a bell-shaped outline with a curved orbital margin (although variable in Portuguese specimens), and a flabellate, bulbous-shaped internasal process. The species is more similar to C. megacephalus than C. ibericus, but its phylogenetic position comprises an unresolved trichotomy. Our results show that intraspecific variation and homoplasy render the fused frontal non-diagnostic below the generic level.

Costa, Lúcia AA, Marta Mateus, João Paulo Borges, Jorge Carvalho Silva, Susana Barreiros, and Paula I. P. Soares. "Superparamagnetic Iron Oxide Nanozymes for Synergistic Cancer Treatment." 8.1 (2022): 3. Abstract
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Oliveira, Tiago, Pedro Matias, and Corneliu Cismasiu. "Análise Experimental e Numérica de Painéis de Vidro Laminado Sujeitos à Ação de Explosões." 4.o ENCONTRO DE I&D EM CIÊNCIAS MILITARES – ECM 2022. Sintra: Academia da Força Aérea, 2022.
Carvalho, Patrícia M., Eva Marguí, Aldona Kubala-Kukuś, Dariusz Banaś, Jorge Machado, Diogo Casal, Diogo Pais, José Paulo Santos, and Sofia Pessanha. "Evaluation of different analytical approaches using total reflection X-ray fluorescence systems for multielemental analysis of human tissues with different adipose content." Spectrochimica Acta - Part B Atomic Spectroscopy. 198 (2022). Abstract

Elemental content plays an important role in biological processes, and so, the multielemental analysis of human tissue samples is required in biomedical research. Still, the small amount of available biological samples and the adipose content of the samples can be major setbacks for the accurate determination of elemental content. In this study, we explored the potential of several analytical approaches combined with total reflection X-ray fluorescence spectrometry (TXRF) for multielemental analysis of human tissues with different adipose content (colon, heart, liver, lung, muscle, intestine, skin, stomach, uterus, bladder and aorta). The capabilities and limitations of different sample treatment procedures (suspension and acidic digestion) and two TXRF systems with different anode configurations (Mo and W X-ray tubes) have been evaluated for such purpose. Results showed that for tissues with a higher fat content (e.g., skin, and intestine) the best strategy was the acidic digestion of the sample before TXRF analysis. However, for other tissues, acceptable results were obtained by suspending 20 mg of powdered material in 1 mL of 2 M nitric acid. A further enhancement of the limits of detection and accuracy of the results was achieved if using Mo-TXRF systems, especially for the determination of low Z elements (e.g., K, and Ca) and of elements present at low concentrations (e.g., Cu) in the human tissues. Finally, results by TXRF analysis were compared with those obtained with μ-EDXRF and ICP-OES, and a good agreement was obtained.

Pereira, Miguel Alves, Duarte Caldeira Dinis, Diogo Cunha Ferreira, José Rui Figueira, and Rui Cunha Marques. "A network Data Envelopment Analysis to estimate nations’ efficiency in the fight against SARS-CoV-2." Expert Systems with Applications. 210 (2022): 118362. AbstractWebsite
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Mateus, Octávio, and Darío Estraviz-López. "A new theropod dinosaur from the early cretaceous (Barremian) of Cabo Espichel, Portugal: Implications for spinosaurid evolution." PLOS ONE. 17 (2022): 1-48. Abstractjournal.pone_.0262614.pdfWebsite

Spinosaurids are some of the most enigmatic Mesozoic theropod dinosaurs due to their unique adaptations to aquatic environments and their relative scarcity. Their taxonomy has proven to be especially problematic. Recent discoveries from Western Europe in general, specifically Iberia, provide some of the best specimens for the understanding of their phylogeny, leading to the description of the spinosaurid Vallibonavenatrix cani and the recognition of the Iberian dinosaur Camarillasaurus cirugedae as one of them. Portuguese associated spinosaurid remains (ML1190) from the Papo Seco Formation (early Barremian) were previously assigned to Baryonyx walkeri but new material recovered in 2020 along with new phylogenetic analyses suggests a different phylogenetic placement, making their revision necessary. Here we show that these remains are not attributable to Baryonyx walkeri, but to a new genus and species, Iberospinus natarioi, gen. et sp. nov. The new taxon is characterized by the presence of a single Meckelian foramen in the Meckelian sulcus, a straight profile of the ventral surface of the dentary and a distal thickening of the acromion process of the pubis between other characters. Iberospinus natarioi is recovered as a sister taxon of the clade formed by Baryonyx and Suchomimus, and outside Spinosaurinae when Vallibonaventrix cani is excluded from the analysis. The description of this taxon reinforces Iberia as a hotspot for spinosaur biodiversity, with several endemic taxa for the region. As expected for the clade, the dentary displays a highly vascularized neurovascular network. The morphometric analysis of parts of the skeleton (pedal phalanx and caudal vertebrae, among others) shows an intermediate condition between basal tetanurans and spinosaurines.

Rotatori, Filippo Maria, Miguel Moreno-Azanza, and Octávio Mateus. "Reappraisal and new material of the holotype of Draconyx loureiroi (Ornithischia: Iguanodontia) provide insights on the tempo and modo of evolution of thumb-spiked dinosaurs." Zoological Journal of the Linnean Society (2022). Abstractrotatori_etal2022.pdfWebsite

{The Upper Jurassic Lourinhã Formation is well known for its rich assemblage of fossil vertebrates. In this formation, ornithopod dinosaurs are represented by two iguanodontian species, Eousdryosaurus nanohallucis and Draconyx loureiroi. We recently became aware of unreported material belonging to the holotype of Draconyx loureiroi, consisting of partially articulated manual elements. We here re-describe the holotype specimen ML 357, including the newly discovered material. The specimen was subjected to CT-scanning and its surface data used to assess anatomical characters. Linear measurements of metatarsal III were used to estimate the body length of the specimen. The Draconyx loureiroi holotype was included in two datasets and analysed with maximum parsimony and Bayesian inference approaches to estimate evolutionary rates among Iguanodontia. We present evidence that Draconyx loureiroi is a valid taxon nested in Styracosterna and is clearly diagnosable by a unique combination of characters. Both maximum parsimony and Bayesian inference indicate high evolutionary rates across the Jurassic/Cretaceous transition for the base of Iguanodontia. Length estimation suggests that Draconyx loureiroi was a relatively small, bipedal and possibly cursorial animal. Given its basal phyletic position, we interpret this bauplan was the ancestral condition for Styracosterna, that only later in the Cretaceous evolved into giant quadrupedal forms.}

Teixeira, P., C. Martins, and H. Rocha Abordagem STEAM: articulação disciplinar e práticas letivas de professores. Atas do Encontro de Investigação em Educação Matemática., 2022.
Martins, NFM, and P. Mota. "An adapted plane waves method for heat conduction problems." Applied Mathematics and Computation. 415 (2022). AbstractWebsite

In this paper we construct a new set of basis functions for the numerical solution of nonhomogeneous heat conduction problems with Dirichlet boundary conditions and null initial data. These functions can be seen as Newtonian potentials of plane waves for the heat equation and satisfy a null initial condition. Density results for adapted waves will be established and several numerical simulations will be presented in order to discuss the accuracy and feasibility of the proposed method. An application of the method for heat problems with non null initial temperature will also be discussed.

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