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2020
Syndikus, I., M. Petri, A. O. Macchiavelli, S. Paschalis, C. A. Bertulani, T. Aumann, H. Alvarez-Pol, L. Atar, S. Beceiro-Novo, J. Benlliure, J. M. Boillos, K. Boretzky, M. J. G. Borge, B. A. Brown, M. Caamano, C. Caesar, E. Casarejos, W. Catford, J. Cederkäll, S. Chakraborty, L. V. Chulkov, D. Cortina-Gil, E. Cravo, R. Crespo, Datta U. Pramanik, I. Dillmann, Diaz P. Fernandez, Z. Elekes, J. Enders, F. Farinon, L. M. Fraile, D. Galaviz, H. Geissel, R. Gernhäuser, P. Golubev, K. Göbel, M. Heil, M. Heine, A. Heinz, A. Henriques, M. Holl, H. T. Johansson, B. Jonson, N. Kalantar-Nayestanaki, R. Kanungo, A. Kelic-Heil, T. Kröll, N. Kurz, C. Langer, T. Le Bleis, J. Machado, J. Marganiec-Gałązka, E. Nacher, T. Nilsson, C. Nociforo, V. Panin, A. Perea, S. B. Pietri, R. Plag, A. Rahaman, R. Reifarth, A. Revel, G. Ribeiro, C. Rigollet, D. M. Rossi, D. Savran, H. Scheit, H. Simon, O. Sorlin, O. Tengblad, Y. Togano, M. Vandebrouck, V. Volkov, F. Wamers, C. Wheldon, G. L. Wilson, J. S. Winfield, H. Weick, P. Woods, D. Yakorev, M. Zhukov, A. Zilges, K. Zuber, and R. 3B. collaboration. "{Probing the Z=6 spin-orbit shell gap with (p,2p) quasi-free scattering reactions}." Physics Letters B. 809 (2020): 135748. AbstractWebsite

Physics Letters B, 809 (2020) 135748. 10.1016/j.physletb.2020.135748

Couto, Paula, Maria João Falcão Silva, Manuel Baião, Fernando Pinho, and Tiago Neto. "Tecnologia e custos em obras de reabilitação de edifícios escolares." CIRMARE 2020 - V Congresso Internacional “Recuperação, Manutenção e Reabilitação de Edifícios”. Online & Universidade Federal do Rio de Janeiro 2020.
Neto, Tiago, Paula Couto, Maria João Falcão Silva, and Fernando Pinho. "Costs and technologies in school buildings rehabilitation works." REHABEND 2020 - Euro-American Congress on Construction Pathology, Rehabilitation Technology and Heritage Management. ISBN: 978-84-09-17873-5. University of Cantabria, Spain 2020.
Carreira, Cíntia, Rute F. Nunes, Olga Mestre, Isabel Moura, and Sofia R. Pauleta. "The effect of pH on Marinobacter hydrocarbonoclasticus denitrification pathway and nitrous oxide reductase." 25.7 (2020): 927-940. AbstractWebsite

Increasing atmospheric concentration of N2O has been a concern, as it is a potent greenhouse gas and promotes ozone layer destruction. In the N-cycle, release of N2O is boosted upon a drop of pH in the environment. Here, Marinobacter hydrocarbonoclasticus was grown in batch mode in the presence of nitrate, to study the effect of pH in the denitrification pathway by gene expression profiling, quantification of nitrate and nitrite, and evaluating the ability of whole cells to reduce NO and N2O. At pH 6.5, accumulation of nitrite in the medium occurs and the cells were unable to reduce N2O. In addition, the biochemical properties of N2O reductase isolated from cells grown at pH 6.5, 7.5 and 8.5 were compared for the first time. The amount of this enzyme at acidic pH was lower than that at pH 7.5 and 8.5, pinpointing to a post-transcriptional regulation, though pH did not affect gene expression of N2O reductase accessory genes. N2O reductase isolated from cells grown at pH 6.5 has its catalytic center mainly as CuZ(4Cu1S), while that from cells grown at pH 7.5 or 8.5 has it as CuZ(4Cu2S). This study evidences that an in vivo secondary level of regulation is required to maintain N2O reductase in an active state.

Gavinho, Sílvia Rodrigues, Mariana Castro Soares, João Paulo Borges, Jorge Carvalho Silva, Isabel Sá Nogueira, and Manuel Pedro Fernandes Graça. "Preparation and Characterization of Zinc and Magnesium Doped Bioglasses." Nanoscience and Nanotechnology in Security and Protection against CBRN Threats. Springer, Dordrecht, 2020. 465-475. Abstract
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Simões, J. T., L. C. Neves, Nunes A. Antão, and Costa N. M. da Guerra. "Reliability assessment of shallow foundations on undrained soils considering soil spatial variability." Computers and Geotechnics. 119 (2020).
Coronelli, Dario, Aurelio Muttoni, Ion R. Pascu, Antonio P. Ramos, and Teresa Netti. "A state of the art of flat-slab frame tests for gravity and lateral loading." Structural Concrete. n/a (2020). AbstractWebsite

Abstract This paper presents a critical review of the state of the art of experimental research concerning the seismic response of reinforced concrete flat slab frames. After a summary of tests on connections, the paper examines tests carried out on frames with gravity and cyclic lateral loading, and shake table tests; scaled specimens and one real scale study are included. A discussion of the results reached so far is provided focusing on the global response, the different load types and effects; the ultimate rotations at failure in relation to the gravity shear and a classification of different failure modes for different types of connections. Based on this analysis, the research needs are highlighted. An experimental program launched to address these open questions is described. Further open topics are highlighted.

Penalva, H., M. I. Gomes, F. Caeiro, and M. M. Neves. "Lehmer{'}s mean-of-order-p extreme value index estimation: a simulation study and applications." Journal of Applied Statistics. 47 (2020): 2825-2845. Abstract
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Sanchez-Sobrado, O., MJ Mendes, T. Mateus, J. Costa, D. Nunes, H. Aguas, E. Fortunato, and R. Martins. "Photonic-structured TCO front contacts yielding optical and electrically enhanced thin-film solar cells." Solar Energy. 196 (2020): 92-98. AbstractWebsite
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2019
Cunha, Rita, Miguel Malaca, Vasco Sampaio, Bruno Guerreiro, Paraskevi Nousi, Ioannis Mademlis, Anastasios Tefas, and Ioannis Pitas. "Gimbal Control for Vision-based Target Tracking." Workshop on Signal Processing Computer vision and Deep Learning for Autonomous Systems, EUSIPCO2019. 2019. Abstract
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Mademlis, Ioannis, Arturo Torres-González, Jesús Capitán, Rita Cunha, Bruno Guerreiro, Alberto Messina, Fulvio Negro, Cedric Le Barz, Tiago Gonçalves, and Anastasios Tefas. "A Multiple-UAV Software Architecture for Autonomous Media Production." Workshop on Signal Processing Computer vision and Deep Learning for Autonomous Systems, EUSIPCO2019. 2019. Abstract
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Pandeirada, Carolina O., Élia Maricato, Sónia S. Ferreira, Viviana G. Correia, Benedita A. Pinheiro, Dmitry V. Evtuguin, Angelina S. Palma, Alexandra Correia, Manuel Vilanova, Manuel A. Coimbra, and Cláudia Nunes. "{Structural analysis and potential immunostimulatory activity of Nannochloropsis oculata polysaccharides.}." Carbohydrate polymers. 222 (2019): 114962. Abstract

The relevance of microalgae biotechnology for producing high-value compounds with biomedical application, such as polysaccharides, has been increasing. Despite this, the knowledge about the composition and structure of microalgae polysaccharides is still scarce. In this work, water-soluble polysaccharides from Nannochloropsis oculata were extracted, fractionated, structurally analysed, and subsequently tested in terms of immunostimulatory activity. A combination of sugar and methylation analysis with interaction data of carbohydrate-binding proteins using carbohydrate microarrays disclosed the complex structural features of the different polysaccharides. These analyses showed that the water-soluble polysaccharides fractions from N. oculata were rich in ($\beta$1→3, $\beta$1→4)-glucans, ($\alpha$1→3)-, ($\alpha$1→4)-mannans, and anionic sulphated heterorhamnans. The immunostimulatory assay highlighted that these fractions could also stimulate murine B-lymphocytes. Thus, the N. oculata water-soluble polysaccharides show potential to be further explored for immune-mediated biomedical applications.

Micaelo, Rui, José Neves, Rui Lopes, and Alexandra Jesus. "A Different Perspective on the Production and Application of Warm Mix Asphalt Under Unfavorable Temperature Conditions." Transportation and Geotechniques: Materials, Sustainability and Climate. Eds. Manik Barman, Musharraf Zaman, and Jia-Ruey Chang. Cham: Springer International Publishing, 2019. 20-32. Abstract

Warm mix asphalt (WMA) is produced by a variety of technologies at lower temperatures that enable to gain important environmental and social benefits and, in consequence, to contribute to a more sustainable transportation infrastructure. The producer usually defines the temperatures used in WMA production. However, some references suggest the increase of temperature in order to allow a longer time to transport or to compact in cases of unfavourable weather conditions, mainly under low temperatures. The objective of this paper is to analyse the feasibility of producing WMA at the same temperatures of hot mix asphalt (HMA) guaranteeing an adequate compaction, and final performance in service. The paper describes a laboratory study to investigate the properties of a WMA using different additives and varying the mixing and compaction temperatures. The effect of production temperatures on the performance of the WMA was evaluated through binder drainage (production phase), volumetric properties (compaction phase), and resistance to permanent deformation (service phase). The paper also presents a numerical study on the time available for paving WMA under unfavourable climatic conditions. Results demonstrated that it is possible to produce WMA at high temperatures without problems of binder drainage, during transport, and of performance in service if adequate compaction is achieved. In fact, the production temperatures influenced the compaction phase. However, it is possible to increase the temperature without negatively affecting the required volumetric properties. The rut depth of the permanent deformation test was mostly influenced by the air-voids of the compacted WMA and the binder. From the numerical study, it was concluded that the time available for in situ compaction increased substantially when WMA was paved at higher temperature. However, in cases of low air temperature and thin layer, the increase of temperature may not be sufficient to obtain the desired level of density or air-voids.

Nóbrega, C. S., and S. R. Pauleta Reduction of hydrogen peroxide in gram-negative bacteria – bacterial peroxidases. Vol. 74. Advances in Microbial Physiology, 74., 2019. AbstractWebsite
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Boavida, Nuno, António Moniz, Juan Aransanz, Pablo Sanz de Miguel, Maria Caprile, Julia Frias, Linda Nierling, Bettina-Johanna Krings, Leon Küstermann, Csaba Makó, Miklós Illéssy, and Katalin Bácsi Work in digital platforms: Literature review from Germany, Hungary, Portugal and Spain. Lisbon: CICS.NOVA, 2019. Abstract

This 1st Report of the project CrowdWork21 presents a summary of the information collected about workers in digital platforms by country (German, Hungary, Portugal and Spain). Each national report describes first the scientific debates about workers of digital platforms. After, the reports present the information collected about the national public debates and identifies the angles normally covered by the media in relation to the organisation of digital workers. Lastly, the reports present initial conclusions about the information collected in each country.

Micaelo, R., J. Neves, Mauro Antunes, and D. Aelenei. "Avaliação experimental das propriedades térmicas de misturas betuminosas." 2º Congresso de Ensaios e Experimentação em Engenharia Civil. Porto 2019. Abstract

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Furtado, A., J. Gavina, A. Napoleão, J. Pereira, M. T. Cidade, and J. Sousa. "Density measurements of viscoelastic samples with oscillation type density meters." J. Phys.: Conf. Ser.. 1379.012020 (2019).
Mateus, Octávio, Pedro M. Callapez, Michael J. Polcyn, Anne S. Schulp, António Olímpio Gonçalves, and Louis L. Jacobs. "O registo fóssil da biodiversidade em Angola ao longo do tempo: uma perspectiva paleontológica." Biodiversidade de Angola: Ciência e Conservação - Uma Síntese Moderna. Eds. Huntley B.J., Russo V., Lages F., and Ferrand N. Porto: Arte & Ciência, 2019. 89-116. Abstractmateus_et_al_2019_paleobiodiversidade_angola.pdf

Este capítulo apresenta uma visão geral da paleobiodiversidade alfa de Angola com base no registo fóssil disponível, o qual se limita às rochas sedimentares, a sua idade variando entre o Pré‑Câmbrico e o pre‑
sente. O período geológico com a maior paleobiodiversidade no registo fóssil angolano é o Cretácico, com mais de 80% do total dos táxones fósseis conhecidos, especialmente moluscos marinhos, sendo estes na sua maioria
amonites. Os vertebrados representam cerca de 15% da fauna conhecida e cerca de um décimo destes são espécies descritas pela primeira vez com base em espécimes de Angola.

Holl, M., V. Panin, H. Alvarez-Pol, L. Atar, T. Aumann, S. Beceiro-Novo, J. Benlliure, C. A. Bertulani, J. M. Boillos, K. Boretzky, M. Caamano, C. Caesar, E. Casarejos, W. Catford, J. Cederkäll, L. Chulkov, D. Cortina-Gil, E. Cravo, I. Dillmann, Diaz P. Fernandez, Z. Elekes, J. Enders, L. M. Fraile, Galaviz D. Redondo, R. Gernhäuser, P. Golubev, T. Heftrich, M. Heil, M. Heine, A. Heinz, A. Henriques, H. T. Johansson, B. Jonson, N. Kalantar-Nayestanaki, R. Kanungo, A. Kelic-Heil, T. Kröll, N. Kurz, C. Langer, T. Le Bleis, S. Lindberg, J. Machado, E. Nacher, M. A. Najafi, T. Nilsson, C. Nociforo, S. Paschalis, M. Petri, R. Reifarth, G. Ribeiro, C. Rigollet, D. M. Rossi, D. Savran, H. Scheit, H. Simon, O. Sorlin, I. Syndikus, O. Tengblad, Y. Togano, M. Vandebrouck, P. Velho, F. Wamers, H. Weick, C. Wheldon, G. L. Wilson, J. S. Winfield, P. Woods, M. Zhukov, K. Zuber, and R. 3B. collaboration. "{Quasi-free neutron and proton knockout reactions from light nuclei in a wide neutron-to-proton asymmetry range}." Physics Letters B. 795 (2019): 682-688. AbstractWebsite

Physics Letters B, 795 (2019) 682–688. 10.1016/j.physletb.2019.06.069

2018
Araújo, Andreia, Manuel J. Mendes, Tiago Mateus, João Costa, Daniela Nunes, Elvira Fortunato, Hugo Águas, and Rodrigo Martins. "{Ultra-fast plasmonic back reflectors production for light trapping in thin Si solar cells}." Solar Energy. 174 (2018): 786-792. Abstract

A fast method is presented to fabricate plasmonic light trapping structures in just ten minutes ({\textgreater}5 × faster than the present state of art), with excellent light scattering properties. The structures are composed of silver nanoparticles (Ag NPs) deposited by thermal evaporation and self-assembled using a rapid thermal annealing (RTA) system. The effect of the RTA heating rate on the NPs production reveals to be crucial to the decrease of the annealing process. The Ag NPs are integrated in thin film silicon solar cells to form a plasmonic back reflector (PBR) that causes a diffused light reflectivity in the near-infrared (600–1100 nm wavelength region). In this configuration the thicknesses of the AZO spacer/passivating layers between NPs and rear mirror, and between NPs and silicon layer, play critical roles in the near-field coupling of the reflected light towards the solar cell absorber, which is investigated in this work. The best spacer thicknesses were found to be 100 and 60 nm, respectively, for Ag NPs with preferential sizes of about 200 nm. The microcrystalline silicon ($μ$c-Si:H) solar cells deposited on such improved PBR demonstrate an overall 11{%} improvement on device efficiency, corresponding to a photocurrent of 24.4 mA/cm2 and an efficiency of 6.78{%}, against 21.79 mA/cm2 and 6.12{%}, respectively, obtained on flat structures without NPs.

{T. Vicente}, António, Andreia Araújo, Manuel J. Mendes, Daniela Nunes, Maria J. Oliveira, Olalla Sanchez-Sobrado, Marta P. Ferreira, Hugo Águas, Elvira Fortunato, and Rodrigo Martins. "{Multifunctional cellulose-paper for light harvesting and smart sensing applications}." Journal of Materials Chemistry C. 6 (2018): 3143-3181. AbstractWebsite

{\textless}p{\textgreater}Opto-electronics on/with paper is fostering a novel generation of flexible and recyclable devices for sunlight harvesting and intelligent optical sensing.{\textless}/p{\textgreater}

Neves, F., A. Stark, N. Schell, MJ Mendes, H. Aguas, E. Fortunato, R. Martins, J. B. Correia, and A. Joyce. "{Investigation of single phase Cu2ZnSnxSb1-xS4 compounds processed by mechanochemical synthesis}." Physical Review Materials. 2 (2018). Abstract

The copper zinc tin sulfide (CZTS) compound is a promising candidate as an alternative absorber material for thin-film solar cells. In this study, we investigate the direct formation of Cu1.92ZnSnx(Sb1-x)S4 compounds [CZT(A)S], with x=1, 0.85, 0.70, and 0.50, via a mechanochemical synthesis (MCS) approach, starting from powders of the corresponding metals, zinc sulfide, and sulfur. The thermal stability of the CZT(A)S compounds was evaluated in detail by in situ synchrotron high-energy x-ray diffraction measurements up to 700 °C. The CZT(A)S compounds prepared via MCS revealed a sphalerite-type crystal structure with strong structural stability over the studied temperature range. The contribution of the MCS to the formation of such a structure at room temperature is analyzed in detail. Additionally, this study provides insights into the MCS of CZTS-based compounds: the possibility of a large-scale substitution of Sn by Sb and the production of single phase CZT(A)S with a Cu-poor/Zn-poor composition. A slight increase in the band gap from 1.45 to 1.49-1.51 eV was observed with the incorporation of Sb, indicating that these novel compounds can be further explored for thin-film solar cells.

Monteiro, C. M. B., F. D. Amaro, M. S. Sousa, M. Abdou-Ahmed, P. Amaro, F. Biraben, T. Chen, D. S. Covita, A. J. Dax, M. Diepold, L. M. P. Fernandes, B. Franke, S. Galtier, A. L. Gouvea, J. Götzfried, T. Graf, T. W. Hänsch, M. Hildebrandt, P. Indelicato, L. Julien, K. Kirch, A. Knecht, F. Kottmann, J. J. Krauth, Y. Liu, J. Machado, F. Mulhauser, B. Naar, T. Nebel, F. Nez, R. Pohl, J. P. Santos, J. M. F. dos Santos, K. Schuhmann, C. I. Szabo, D. Taqqu, J. F. C. A. Veloso, and A. Antognini. "{On the double peak structure of avalanche photodiode response to monoenergetic x-rays at various temperatures and bias voltages}." Journal of Instrumentation. 13 (2018): C01033. Abstract
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Rovisco, Ana, Rita Branquinho, Jorge Martins, Maria João Oliveira, Daniela Nunes, Elvira Fortunato, Rodrigo Martins, and Pedro Barquinha. "{Seed-Layer Free Zinc Tin Oxide Tailored Nanostructures for Nanoelectronic Applications: Effect of Chemical Parameters}." ACS Applied Nano Materials. 1 (2018): 3986-3997. AbstractWebsite

Semiconductor nanowires are mostly processed by complex, expensive and high temperature methods. In this work, with the intent of developing zinc tin oxide nanowires (ZTO NWs) by low-cost and low-complexity processes, we show a detailed study on the influence of chemical parameters in the hydrothermal synthesis of ZTO nanostructures at temperatures of only 200 °C. Two different zinc precursors, the ratio between zinc and tin precursors, the concentration of the surfactant agent and of the mineralizer were studied. The type and the crystallinity of the nanostructures was found to be highly dependent on the used precursors and on the concentration of each reagent. Conditions for obtaining different ZTO nanostructures were achieved, namely Zn2SnO4 nanoparticles and ZnSnO3 nanowires with length ≈ 600 nm, with the latter being reported for the first time ever by hydrothermal methods without the use of seed layers. Optical and electrical properties were analyzed, being obtained band gaps of 3.60 and 3.46 eV, fo...