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2020
Martins, Jorge, Asal Kiazadeh, Joana V. Pinto, Ana Rovisco, Tiago Gonçalves, Jonas Deuermeier, Eduardo Alves, Rodrigo Martins, Elvira Fortunato, and Pedro Barquinha. "{Ta2O5/SiO2 Multicomponent Dielectrics for Amorphous Oxide TFTs}." Electronic Materials. 2 (2020): 1-16. AbstractWebsite

Co-sputtering of SiO2 and high-$ąppa$ Ta2O5 was used to make multicomponent gate dielectric stacks for In-Ga-Zn-O thin-film transistors (IGZO TFTs) under an overall low thermal budget (T = 150 °C). Characterization of the multicomponent layers and of the TFTs working characteristics (employing them) was performed in terms of static performance, reliability, and stability to understand the role of the incorporation of the high-$ąppa$ material in the gate dielectric stack. It is shown that inherent disadvantages of the high-$ąppa$ material, such as poorer interface properties and poor gate insulation, can be counterbalanced by inclusion of SiO2 both mixed with Ta2O5 and as thin interfacial layers. A stack comprising a (Ta2O5)x(SiO2)100 − x film with x = 69 and a thin SiO2 film at the interface with IGZO resulted in the best performing TFTs, with field-effect mobility (µFE) ≈ 16 cm2·V−1·s−1, subthreshold slope (SS) ≈ 0.15 V/dec and on/off ratio exceeding 107. Anomalous Vth shifts were observed during positive gate bias stress (PGBS), followed by very slow recoveries (time constant exceeding 8 × 105 s), and analysis of the stress and recovery processes for the different gate dielectric stacks showed that the relevant mechanism is not dominated by the interfaces but seems to be related to the migration of charged species in the dielectric. The incorporation of additional SiO2 layers into the gate dielectric stack is shown to effectively counterbalance this anomalous shift. This multilayered gate dielectric stack approach is in line with both the large area and the flexible electronics needs, yielding reliable devices with performance suitable for successful integration on new electronic applications.

Rovisco, Ana, Andreia dos Santos, Tobias Cramer, Jorge Martins, Rita Branquinho, Hugo Águas, Beatrice Fraboni, Elvira Fortunato, Rodrigo Martins, Rui Igreja, and Pedro Barquinha. "{Piezoelectricity Enhancement of Nanogenerators Based on PDMS and ZnSnO 3 Nanowires through Microstructuration}." ACS Applied Materials & Interfaces. 12 (2020): 18421-18430. AbstractWebsite

The current trend for smart, self-sustainable, and multifunctional technology demands for the development of energy harvesters based on widely available and environmentally friendly materials. In this context, ZnSnO3 nanostructures show promising potential because of their high polarization, which can be explored in piezoelectric devices. Nevertheless, a pure phase of ZnSnO3 is hard to achieve because of its metastability, and obtaining it in the form of nanowires is even more challenging. Although some groups have already reported the mixing of ZnSnO3 nanostructures with polydimethylsiloxane (PDMS) to produce a nanogenerator, the resultant polymeric film is usually flat and does not take advantage of an enhanced piezoelectric contribution achieved through its microstructuration. Herein, a microstructured composite of nanowires synthesized by a seed-layer free hydrothermal route mixed with PDMS (ZnSnO3@PDMS) is proposed to produce nanogenerators. PFM measurements show a clear enhancement of d33 for single ZnSnO3 versus ZnO nanowires (23 ± 4 pm/V vs 9 ± 2 pm/V). The microstructuration introduced herein results in an enhancement of the piezoelectric effect of the ZnSnO3 nanowires, enabling nanogenerators with an output voltage, current, and instantaneous power density of 120 V, 13 $μ$A, and 230 $μ$W·cm-2, respectively. Even using an active area smaller than 1 cm2, the performance of this nanogenerator enables lighting up multiple LEDs and other small electronic devices, thus proving great potential for wearables and portable electronics.

Silva, Sara, Maria João Falcão, Paula Couto, and Fernando Pinho. "BIM methodology in energetic rehabilitation of buildings: application to a public research laboratory." REHABEND 2020 - Euro-American Congress on Construction Pathology, Rehabilitation Technology and Heritage Management. ISBN: 978-84-09-17873-5. University of Cantabria, Spain 2020.
Favinha, André G., Daniela S. Barreiro, Joana N. Martins, Philip O'Toole, and Sofia R. Pauleta. "Acrylamide-hemoglobin adduct: A spectroscopic study." 241 (2020): 118644. AbstractWebsite

Acrylamide is a neurotoxic and carcinogenic organic compound that is able to bind to several biomolecules and form adducts, through nucleophilic addition and in vivo by the Maillard Reaction, interfering with the biological functions of these molecules. Hemoglobin is one of the most abundant intracellular blood proteins, and thus it is of high interest to understand whether the binding of acrylamide can alter its properties. The interaction of acrylamide with hemoglobin was assessed in a 20:1 ratio, and after a 72 h-incubation period, a decrease of ca. 50% in the absorbance of the hemoglobin's Soret band was observed at 37 °C. This together with the analysis of circular dichroism spectra indicate that acrylamide binds in close proximity to the heme group. These perturbations were confirmed to not correspond to the loss of the heme group and were mostly reverted after passing the protein through a size-exclusion chromatographic matrix, suggesting a dominant non-covalent interaction for the observed effect. The thermodynamic parameters of unfolding in the absence and presence of acrylamide, suggest an interaction based on H-bonds and van der Waals forces that slightly stabilizes hemoglobin. The oxygen binding capacity of hemoglobin does not seem to be hindered, as no differences in the Q bands were observed in the adduct.

Perdigão, Patrícia, Bruno Miguel Morais Faustino, Jaime Faria, João Paulo Canejo, João Paulo Borges, Isabel Ferreira, and Ana Catarina Baptista. "Conductive Electrospun Polyaniline/Polyvinylpyrrolidone Nanofibers: Electrical and Morphological Characterization of New Yarns for Electronic Textiles." 8.4 (2020): 24. Abstract
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Teixeira, L. R., C. M. Cordas, M. P. Fonseca, N. E. C. Duke, P. R. Pokkuluri, and C. A. Salgueiro. "Modulation of the Redox Potential and Electron/Proton Transfer Mechanisms in the Outer Membrane Cytochrome OmcF From Geobacter sulfurreducens." Frontiers in Microbiology. 10 (2020). AbstractWebsite
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Gomes, Ana Sara, Helena Ramos, Sara Gomes, Joana B. Loureiro, Joana Soares, Valentina Barcherini, Paola Monti, Gilberto Fronza, Carla Oliveira, Lucília Domingues, Margarida Bastos, Daniel F. A. R. Dourado, Ana Luísa Carvalho, Maria João Romão, Benedita Pinheiro, Filipa Marcelo, Alexandra Carvalho, Maria M. M. Santos, and Lucília Saraiva. "SLMP53-1 interacts with wild-type and mutant p53 DNA-binding domain and reactivates multiple hotspot mutations." 1864.1 (2020): 129440. AbstractWebsite

BackgroundHalf of human cancers harbour TP53 mutations that render p53 inactive as a tumor suppressor. As such, reactivation of mutant (mut)p53 through restoration of wild-type (wt)-like function represents one of the most promising therapeutic strategies in cancer treatment. Recently, we have reported the (S)-tryptophanol-derived oxazoloisoindolinone SLMP53-1 as a new reactivator of wt and mutp53 R280K with in vitro and in vivo p53-dependent antitumor activity. The present work aimed a mechanistic elucidation of mutp53 reactivation by SLMP53-1.
Methods and results
By cellular thermal shift assay (CETSA), it is shown that SLMP53-1 induces wt and mutp53 R280K thermal stabilization, which is indicative of intermolecular interactions with these proteins. Accordingly, in silico studies of wt and mutp53 R280K DNA-binding domain with SLMP53-1 unveiled that the compound binds at the interface of the p53 homodimer with the DNA minor groove. Additionally, using yeast and p53-null tumor cells ectopically expressing distinct highly prevalent mutp53, the ability of SLMP53-1 to reactivate multiple mutp53 is evidenced.
Conclusions
SLMP53-1 is a p53-activating agent with the ability to directly target wt and a set of hotspot mutp53.
General Significance
This work reinforces the encouraging application of SLMP53-1 in the personalized treatment of cancer patients harboring distinct p53 status.

Ribau, A. M., L. Ferrás, M. L. Morgado, M. Rebelo, and A. Afonso. "Analytical and numerical studies for slip flows of a generalised Phan-Thien-Tanner fluid." ZAMM Journal of applied mathematics and mechanics: Zeitschrift für angewandte Mathematik und Mechanik . 100.3 (2020).
Ferrás, L., N. Ford, M. L. Morgado, and M. Rebelo. "High-Order Methods for Systems of Fractional Ordinary Differential Equations and Their Application to Time-Fractional Diffusion Equations." Mathematics in Computer Science (2020).
F.E, Cardoso, Batista; Arnaldo, V. Vassilenko, F. Serrano, and M. Ortigueira. "Idle Tone Detection in Biomedical Signals Using Time-Frequency Techniques." IFIP Advances in Information and Communication Technology. Ed. Technological Innovation Life Improvement. DoCEIS for 2020. Springer, 2020.
Singh, N., A. Amendola, F. Santos, G. Benzoni, and F. Fraternali Innovative dissipative devices with tensegrity architecture and super elastic behaviour for the seismic protection of structures. Proceedings of the International Conference on Structural Dynamic . Athens; Greece: EURODYN, 2020.
Vieira, Manuel V. C., and Flora Ferreira. "Packing Shoes Efficiently." Impact. 2.34-38 (2020).
Petrova, K. T., I. C. F. R. Ferreira, R. C. Calhelha, and M. Sokovic "Phenylpropanoid Saccharide Esters, Methods and Uses Thereof." WO/2020/183442., 2020.
Dimitrova, I., Vítor H. Fernandes, J. Koppitz, and T. M. Quinteiro. "Ranks of monoids of endomorphisms of a finite undirected path (DOI: 10.1007/s40840-019-00762-4)." Bulletin of the Malaysian Mathematical Sciences Society. 43 (2020): 1623-1645. AbstractWebsite

In this paper we study the widely considered endomorphisms and weak endomorphisms of a finite undirected path from monoid generators perspective. Our main aim is to determine the ranks of the monoids $wEnd P_n$ and $End P_n$ of all weak endomorphisms and all endomorphisms of the undirected path $P_n$ with $n$ vertices. We also consider strong and strong weak endomorphisms of $P_n$.

Fernandes, Cláudio A., and Alexei Yu. Karlovich. "Semi-almost periodic Fourier multipliers on rearrangement-invariant spaces with suitable Muckenhoupt weights." Boletín de la Sociedad Matemática Mexicana. 26.3 (2020): 1135-1162.Website
Rocha, H., E. Faggiano, and F. Mennuni. "Teachers as task designers in the digital age: Teaching using technology." Proceedings of the 10th ERME Topic Conference - MEDA 2020. Linz (Austria): ERME, 2020. Abstract2020_meda_rocha_faggiano_mennuni.pdf

The aim of the paper is to present and analyse the case of one teacher attempting to introduce his students to fractals using digital technology. His task design process has been made explicit through the writing of a storyboard. It has been analysed in order to focus on the stages of the process, identifying prominent elements in it by using the knowledge quartet framework. Results can be useful to inform teacher educators about his needs with respect to the development of his ability in task design. The importance of this aspect, particularly worth of note in the digital age in which teachers have many opportunities to access teaching resources online, has been amplified by the constraints to which educational systems have been subjected during the Covid-19 pandemic emergency.

Gomes, M. I., F. Caeiro, F. Figueiredo, L. Henriques-Rodrigues, and D. Pestana. "Corrected-Hill versus partially reduced-bias value-at-risk estimation." Communications in Statistics: Simulation and Computation. 49 (2020): 867-885. Abstract
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Haque, S., M. Alexandre, MJ Mendes, H. Águas, E. Fortunato, and R. Martins. "Design of wave-optical structured substrates for ultra-thin perovskite solar cells." Applied Materials Today. 20 (2020). AbstractWebsite
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Miranda, R., E. Babilio, N. Singh, D. P. Villamil, F. Santos, and F. Fraternali. "Dynamics of tensegrity solar FaÇades operating as mechanical energy harvesters." Proceedings of the International Conference on Structural Dynamic , EURODYN. Vol. 1. 2020. 2113-2122. Abstract
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Ferreira, Johannes Theodorus, Andriëtte Bekker, Filipe Marques, and M. Laidlaw. "An Enriched $\alpha$- $μ$ Model as Fading Candidate." Mathematical Problems in Engineering. 2020 (2020). Abstract
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Modano, M., A. Majumder, F. Santos, R. Luciano, and F. Fraternali. "Fast and Optimized Calculation of the Cable Pretension Forces in Arch Bridges With Suspended Deck." Frontiers in Built Environment. 6 (2020). AbstractWebsite
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Faria, Ricardo, Rui Marreiros, António Pinho Ramos, and Catarina Jesus. "Influence of the top reinforcement detailing in the behaviour of flat slabs." Structures. 23 (2020): 718-730. AbstractWebsite

This paper studies the influence of different longitudinal top reinforcement detailing on the behaviour and punching capacity of flat slabs. Experimental and numerical studies were carried out. The experimental campaign consisted in testing three reinforced concrete slabs 2.20 m wide with a thickness equal to 0.15 m. The numerical study was conducted using the non-linear finite element software ATENA 3D. Using numerical models, which were calibrated using the experimental tests, a parametric study was carried out to include other design solutions beyond the tested ones. The parameters that were changed in this parametric study were the steel reinforcement ratio, the concrete strength and the detailing of the top steel reinforcement, namely using a solution with uniform distribution and other with a higher concentration of reinforcement near the column. Finally, the results were compared with predictions obtained using some of the existing codes (Eurocode 2 and Model Code 2010). From this study it can be concluded that concentrating the top flexural reinforcement, keeping the same total amount of top longitudinal reinforcement, results in a stiffer response, an increment in the punching resistance, and a decrease in the maximum vertical displacement.

Singh, N., A. Amendola, F. Santos, G. Benzoni, and F. Fraternali. "Innovative dissipative devices with tensegrity architecture and super elastic behaviour for the seismic protection of structures." Proceedings of the International Conference on Structural Dynamic , EURODYN. Vol. 2. 2020. 3079-3085. Abstract
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Li, K., S. Haque, A. Martins, E. Fortunato, R. Martins, MJ Mendes, and C. S. Schuster. "Light trapping in solar cells: Simple design rules to maximize absorption." Optica. 7 (2020): 1377-1384. AbstractWebsite
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