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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.

Clemmensen, L. B., D. V. Kent, M. Mau, O. Mateus, and J. Milàn. "Triassic lithostratigraphy of the Jameson Land basin (central East Greenland), with emphasis on the new Fleming Fjord Group." Bulletin of the Geological Society of Denmark. 68 (2020): 95-132. Abstractclemmensen_et_al_2020_triassic_lithostratigraphy_of_the_jameson_land_basin.pdfWebsite

The lithostratigraphy of the Triassic deposits of the Jameson Land Basin in central East Greenland is revised. The new Scoresby Land Supergroup is now composed of the Wordie Creek, Pingo Dal, Gipsdalen and Fleming Fjord Groups. This paper only deals with the lithostratigraphy of the late Early-Late Triassic continental deposits of the latter three groups with emphasis on the vertebratebearing Fleming Fjord Group. The new Pingo Dal Group consists of three new formations, the Rødstaken, Paradigmabjerg and Klitdal Formations (all elevated from members), the new Gipsdalen Group consists of three new formations, the Kolledalen, Solfaldsdal (with the new Gråklint Member) and Kap Seaforth Formations (all elevated from members), and the new Fleming Fjord Group is subdivided into three new formations, the Edderfugledal, Malmros Klint and Ørsted Dal Formations (all elevated from members). The Edderfugledal Formation contains two cyclic bedded, lacustrine members, a lowermost Sporfjeld Member (elevated from beds), and an uppermost Pingel Dal Member (elevated from beds). The lacustrine red beds of the Malmros Klint Formation are not subdivided. The lacustrine and fluvial Ørsted Dal Formation contains three new members. In the eastern and central part of the basin, the formation is initiated by cyclic bedded, red lacustrine mudstones of the Carlsberg Fjord Member (elevated from beds), while in the northwestern part of the basin the lowermost part of the formation is composed of grey fluvial conglomerates and sandstones with subordinate red mudstones of the Bjergkronerne Member (elevated from beds). The uppermost part of the formations in most of the basin is composed of cyclic bedded, variegated lacustrine mudstones and grey to yellowish marlstones of the Tait Bjerg Member (elevated from beds). The sediments in the Fleming Fjord Group contain remains of a rich and diverse vertebrate fauna including dinosaurs, amphibians, turtles, aeotosaurs, pterosaurs, phytosaurs and mammaliaforms. Most vertebrate bones have been found in uppermost Malmros Klint Formation, and in the Carlsberg Fjord and Tait Bjerg Members. The Norian–early Rhaetian, lacustrine Fleming Fjord Group was deposited at about 41° N on the northern part of the supercontinent Pangaea. Lacustrine sedimentation was controlled by seasonal as well as longer-term (orbital) variation in precipitation. Precipitation was probably brought to the basin by southwesterly winds. The lacustrine sediments of the uppermost Fleming Fjord Group show deposition during increasingly humid conditions changing the lake environment from an ephemeral lake-steppe area to a perennial lake. This evolution of lake environment suggests a change from a winter-wet temperate climate to one with precipitation throughout the year.

Laronha, H., I. Carpinteiro, J. Portugal, A. Azul, M. Polido, K. T. Petrova, M. Salema-Oom, and J. CALDEIRA. "“Challenges in Matrix Metalloproteinases Inhibition." Biomolecules. 10 (2020): 717-778. DOI:10.3390/biom10050717.
Torres, Marta, João Correia de Freitas, and Mônica Mesquita. "Coconstrução de um museu virtual. {Literacia}, sustentabilidade e emancipação na disseminação do património cultural das comunidades de pescadores.". Lisboa 2020. Abstract

No contexto do Observatório de Literacia Oceânica, o estudo da coconstrução de um museu virtual online investiga a aprendizagem dos alunos pertencentes às comunidades piscatórias, contribuindo para a literacia histórica. O envolvimento em tarefas concretas associadas à aprendizagem é considerado, consensualmente, um fator de motivação. No presente estudo trabalharam as artes da pesca artesanal, enquadradas por conteú dos da disciplina de História. Utilizando ambientes tecnologicamente enriquecidos, pretende-se compreender as interações entre o conhecimento formal e informal destes alunos, desenvolvendo-se o estudo de forma a que os conhecimentos sejam signi{\textbackslash}icativos e usáveis, promovendo a intervenção na sociedade, enquanto agentes de mudança. A metodologia assentou num estudo empı́rico qualitativo, com base na etnogra{\textbackslash}ia crı́tica, combinado com design-based research, para a construção do protótipo do museu virtual online. As estratégias de ação, técnicas de recolha e aná lise de dados desenvolveram-se num contexto de observação participativa, notas de campo e aplicação de vários instrumentos, bem como na coconstrução do protótipo por aproximações sucessivas estruturantes da plataforma digital selecionada. Constatou-se a ausência de interação entre os saberes formais e informais dos alunos, um desconhecimento da história das suas comunidades, mas também a valorização das histórias de famı́lia. Os alunos foram observadores crı́ticos das suas práticas reconhecendo, por exemplo, a desvalorização dos seus saberes informais e a sua falta de relação com os conteú dos da disciplina de História. Neste processo identi{\textbackslash}icou-se a necessidade de introduzir temáticas relacionadas com a Literacia Histórica, História das Comunidades Capariquenses e Sustentabilidade, considerando-o o meio privilegiado para a disseminação do seu património cultural.

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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Penalva, H., M. Ivette Gomes, F. Caeiro, and M. Manuela Neves. "A couple of non reduced bias generalized means in extreme value theory: An asymptotic comparison." Revstat Statistical Journal. 18 (2020): 281-298. Abstract
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Catalanotti, G., P. Kuhn, J. Xavier, and H. Koerber. "High strain rate characterisation of intralaminar fracture toughness of GFRPs for longitudinal tension and compression failure." Composite Structures. 240 (2020): 112068. AbstractWebsite

The elastic parameters, strengths, and intralaminar fracture toughness are determined for an E-Glass polymer composite material system, statically and at high strain rate, adapting methodologies previously developed by the authors for different carbon composites. Dynamic experiments are conducted using tension and compression Split-Hopkinson Bars (SHBs). A unique set of experimental parameters is obtained, and reported together with the experimental set-up, in order to ensure reproducibility. While in-plane elastic and strength properties were obtained by testing one specimen geometry, intralaminar fracture properties required the testing of different sized notched specimens with scaled geometries. This allowed the use of the size-effect method for the determination of the dynamic R-curve. When comparing these results with those previously obtained for a carbon/epoxy material system, it is observed that the dynamic fracture toughness exhibits a much more significant increase in both tension and compression. The obtained results permit the identification of the softening law at different strain rates, allowing its use in any analytical or numerical strength predictive method.

Torres, Marta, João Correia de Freitas, and Mônica Mesquita. "Historical {Literacy}: a {Virtual} {Museum} for the {Dissemination} of the {Cultural} {Heritage} of {Fishing} {Communities}." Proceedings of {ICERI} 2020 {Conference}. Sevilha: INTED, 2020. 6404-6410. Abstract

This project is inserted in Observatório de Literacia Oceânica, and its aim is the co-construction of a virtual museum of the Fishery Arts, based on History concepts and contents related with formal and informal knowledge. In these communities, the oral and intergenerational transmission of life stories occurs mainly within the family circle. Our main purpose was to find ways that allowed students to acquire usable and significant pasts, and not only fixed histories. The acquisition of historical literacy can change the way they apprehend and make use of knowledge, turning them in to agents of change, disseminators of their cultural heritage, with the help of a technologically enriched environment that enables network communication. The access to digital education should promote students' autonomy and responsibility when constructing knowledge. In the present study, artisanal fishing was the object of study, related to the contents of the discipline of History. Making use of technologically enriched environments we intended to analyse how the interactions between the formal and informal knowledge of these students occurred, developing the study in such a way that their knowledge could be meaningful and usable. It is intended to promote their intervention in society as agents of change, identifying and resolving problems associated with the communities to which they belong. In a perspective of curricular innovation, and considering that a sustainable development implies a change of paradigm in education, the adoption of differentiated, transformative pedagogies aiming an active learning, involving direct participation, collaboration and problem solving for the promotion of school success, it is intended to create a space for critical reflection, generating new knowledge and knowledge shared and enriched so that students participate in the construction of knowledge in order to make it meaningful and usable. Participation and negotiation amongst participants, within a perspective of shared responsibility and active citizenship, promotes cohesion and equality. We have considered the context of the school community and the context of the community in which the project is inserted, so that the tasks / knowledges that students have, can become meaningful and promote the quality and sustainability of the environment in which they are inserted. Education faces challenges that are a reflection of society’s problems. In the search for solutions it is essential the participation and collaboration of students who, with their formal and informal knowledge, can address problems that have cultural, social, political, economic and environmental impacts in their communities, as well as a local, regional and global scope, both in present and past times. Using digital environments and instruments we will try to understand how the interactions between formal and informal knowledge take place and how the performance of students from the fishing communities can be improved. Keywords: historical literacy; formal and informal knowledge; virtual museum.

Peres, R. S., X. Jia, J. Lee, K. Sun, A. W. Colombo, and J. Barata. "Industrial Artificial Intelligence in Industry 4.0 - Systematic Review, Challenges and Outlook." IEEE Access. 8 (2020): 220121-220139. Abstract
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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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Pereira, J. C. R., A. M. P. de Jesus, J. Xavier, J. A. F. O. Correia, L. Susmel, and A. A. Fernandes. "Low and ultra-low-cycle fatigue behavior of X52 piping steel based on theory of critical distances." International Journal of Fatigue (2020): 105482. AbstractWebsite

The cyclic failure observed in structural components such as pipelines subjected to extreme loading conditions highlights some limitations concerning the application of existing fatigue damage models. The evaluation and prediction of this type of failure in these steel components under large-scale plastic yielding associated with high levels of stress triaxiality are not sufficiently known nor explored. This fatigue domain is conventionally called ultra-low-cycle fatigue (ULCF) and damage features are representative of both low-cycle fatigue (LCF) and monotonic ductile fracture. Thus, in order to understand the ULCF damage mechanisms both monotonic and LCF tests are required to get representative bounding damage information to model the material damage behaviour under such extreme loading conditions. This paper aims at exploring the Theory of Critical Distances (TCD) in the LCF and ULCF fatigue regimes, including the application of the point, line and area methods. The application of the TCD theories has not been explored so far in the ULCF fatigue regimes, despite its promising results in the LCF and high-cycle fatigue. An experimental program was carried out on several specimens’ geometries made of X52 piping steel. In detail, smooth plane specimens and notched plane specimens were cyclic loaded under tension/compression loading in order to obtain fatigue lives within the range of 101-104 cycles. In addition, cyclic bending tests on notched plane specimens were also incorporated in this study. Finite element simulations of all small-scale tests were conducted allowing to derive elastoplastic stress/strain fields along the potential crack paths. The numerical data were subjected to a post-processing in order to find characteristic lengths that can be treated as a fatigue property according to the TCD. A unified strain-life relation is proposed for the X52 piping steel together with a characteristic material length, consisting of a practical relation for pipeline strain-based design under extreme cyclic loading conditions.

Santos, F. A., H. Rebelo, M. Coutinho, L. S. Sutherland, C. Cismasiu, I. Farina, and F. Fraternali. "Low velocity impact response of 3D printed structures formed by cellular metamaterials and stiffening plates: PLA vs. PETg." Composite Structures (2020): 113128. AbstractWebsite

This work studies the low-velocity impact response of 3D-printed layered structures made of thermoplastic materials (PLA and PETg), which form sacrificial claddings for impact protection. The analyzed structures are composed of crushable cellular cores placed in between terminal stiffening plates. The cores tessellate either honeycomb hexagonal unit cells, or hexagonal cells with re-entrant corners, with the latter exhibiting auxetic response. The given results highlight that the examined PETg protectors exhibit higher energy dissipation ratios and lower restitution coefficients, as compared to PLA structures that have the same geometry. It is concluded that PETg qualifies as an useful material for the fabrication of effective impact protection gear through ordinary, low-cost 3D printers.

Reboredo, {Fernando Henrique}, A. Barbosa, {Maria Manuela} Silva, {Maria Luisa} Carvalho, {José Paulo} Santos, {Maria Fernanda} Pessoa, Fernando Lidon, {José C. } Ramalho, and Mauro Guerra. "Mineral Content of Food Supplements of Plant Origin, by Energy Dispersive X-ray Fluorescence: A Risk Assessment." Exposure and Health. 12 (2020): 917-927. Abstract

The aim of this study is to evaluate the elemental composition of six food supplements of plant origin, commonly sold in the Portuguese market, by energy dispersive X-ray fluorescence. The presence of arsenic in all the Maca, Ashwagandha, Camu-Camu and Hemp protein samples (except the generic form) is a reason of concern due to the long-term effects of As mainly in its inorganic form. Thus, great caution must be taken on some food supplements, particularly the cases of Moringa from Egypt and Yellow/Xpresso Maca, whose inorganic As concentrations are in line with the upper bound concentration for the 95th dietary exposure according to the European Food Safety Authority which is 0.64 μg/kg bw/day. In what regards Hemp protein, if the supplier’s daily intake recommendation (30 g) is followed, values as high as 1.75 μg/kg bw/day of inorganic As will be consumed, which are dangerously above the upper bound. In this case this specific supplement lot should be removed from the market. Also the consumption of Hemp protein leads to a daily intake of Mn above the Daily Reference Intake (DRI) and Adequate Intakes (AIs) for adults. The contamination of Goji berries by Pb is a reason for concern—organic berries contained 11.3 μg/g while berries derived from conventional agriculture 11.6 μg/g, leading to daily intake doses of 315.3 μg and 324.8 μg, respectively, if the recommended daily intake of 28 g is followed. Our findings point out to an inadequacy of the recommended intakes by the supplier vis a vis the concentrations observed, greatly increasing the risk for public health.

Ribeiro, Diana O., Aldino Viegas, Virgínia M. R. Pires, João Medeiros-Silva, Pedro Bule, Wengang Chai, Filipa Marcelo, Carlos M. G. A. Fontes, Eurico J. Cabrita, Angelina S. Palma, and Ana Luísa Carvalho. "Molecular basis for the preferential recognition of β1,3-1,4-glucans by the family 11 carbohydrate-binding module from Clostridium thermocellum." The FEBS Journal. 287 (2020): 2723-2743. AbstractWebsite

Understanding the specific molecular interactions between proteins and β1,3-1,4-mixed-linked d-glucans is fundamental to harvest the full biological and biotechnological potential of these carbohydrates and of proteins that specifically recognize them. The family 11 carbohydrate-binding module from Clostridium thermocellum (CtCBM11) is known for its binding preference for β1,3-1,4-mixed-linked over β1,4-linked glucans. Despite the growing industrial interest of this protein for the biotransformation of lignocellulosic biomass, the molecular determinants of its ligand specificity are not well defined. In this report, a combined approach of methodologies was used to unravel, at a molecular level, the ligand recognition of CtCBM11. The analysis of the interaction by carbohydrate microarrays and NMR and the crystal structures of CtCBM11 bound to β1,3-1,4-linked glucose oligosaccharides showed that both the chain length and the position of the β1,3-linkage are important for recognition, and identified the tetrasaccharide Glcβ1,4Glcβ1,4Glcβ1,3Glc sequence as a minimum epitope required for binding. The structural data, along with site-directed mutagenesis and ITC studies, demonstrated the specificity of CtCBM11 for the twisted conformation of β1,3-1,4-mixed-linked glucans. This is mediated by a conformation–selection mechanism of the ligand in the binding cleft through CH-π stacking and a hydrogen bonding network, which is dependent not only on ligand chain length, but also on the presence of a β1,3-linkage at the reducing end and at specific positions along the β1,4-linked glucan chain. The understanding of the detailed mechanism by which CtCBM11 can distinguish between linear and mixed-linked β-glucans strengthens its exploitation for the design of new biomolecules with improved capabilities and applications in health and agriculture. Database Structural data are available in the Protein Data Bank under the accession codes 6R3M and 6R31.

Ghosh, Indranil, Filipe Marques, and Subrata Chakraborty. "A new bivariate Poisson distribution via conditional specification: properties and applications." Journal of Applied Statistics (2020): 1-23. Abstract
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Coolen, Frank PA, and Filipe J. Marques. "Nonparametric Predictive Inference for Test Reproducibility by Sampling Future Data Orderings." Journal of Statistical Theory and Practice. 14 (2020): 1-22. 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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Gomes, M. I., F. Caeiro, F. Figueiredo, L. Henriques-Rodrigues, and D. Pestana. "Reduced-bias and partially reduced-bias mean-of-order-p value-at-risk estimation: a Monte-Carlo comparison and an application." Journal of Statistical Computation and Simulation. 90 (2020): 1735-1752. Abstract
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Isufi, B., I. Cismasiu, R. Marreiros, A. Pinho Ramos, and V. Lúcio. "Role of punching shear reinforcement in the seismic performance of flat slab frames." Engineering Structures. 207 (2020). AbstractWebsite
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Cismaşiu, C., F. P. A. Santos, R. A. D. S. Perdigão, V. M. S. Bernardo, P. X. Candeias, A. R. Carvalho, and L. M. C. Guerreiro. "Seismic Vulnerability Assessment of a RC Pedestrian Crossing." Journal of Earthquake Engineering. 24 (2020): 727-744. AbstractWebsite
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Centeno, P., M. F. Alexandre, M. Chapa, JV Pinto, J. Deuermeier, T. Mateus, E. Fortunato, R. Martins, H. Águas, and MJ Mendes. "Self-Cleaned Photonic-Enhanced Solar Cells with Nanostructured Parylene-C." Advanced Materials Interfaces. 7 (2020). AbstractWebsite
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Franco, N., C. Chastre, and H. Biscaia. "Strengthening RC Beams Using Stainless Steel Continuous Reinforcement Embedded at Ends." Journal of Structural Engineering (United States). 146 (2020). AbstractWebsite

An innovative system for the flexural strengthening of RC structures designated continuous reinforcement embedded at ends (CREatE) is presented in this research work. The main characteristics and procedures for the application of this new strengthening technique were described. To evaluate the performance and efficiency of this technique, a set of RC T-beams was subjected to a four-point bending test setup. The reference RC T-beam was not strengthened; all other RC T-beams were strengthened with postinstalled stainless steel bars. Different application arrangements and different amounts of reinforcement were considered, and the CREatE technique was tested under monotonic and cyclic loading histories. The tests were modeled using the nonlinear finite-element method (FEM) to predict the performance of the RC T-beams, which allowed analyzing, in detail and with good agreement with the experiments, the influence of the CREatE technique on the (1) strains developed in the concrete, (2) cracking patterns, and (3) strains developed in the stirrups. Apart from the expected increases in the flexural stiffness and load-bearing capacity of the T-beams, the results showed that the use of the CREatE technique led to higher ductility indexes in the displacement compared with traditional techniques. Moreover, with the CREatE technique, premature debonding of the reinforcement material from the concrete tensioned surface - commonly observed in externally bonded reinforcement (EBR) strengthening systems - was eliminated. © 2020 American Society of Civil Engineers.

Outis, Mani, Vitor Rosa, César AT Laia, João Carlos Lima, Sónia Barroso, Ana Luísa Carvalho, Maria José Calhorda, and Teresa Avilés. "Synthesis, Crystal Structure, and DFT Study of Two New Dinuclear Copper(I) Complexes Bearing Ar-BIAN Ligands Functionalized with NO2 Groups." European Journal of Inorganic Chemistry. 2020 (2020): 2900-2911. AbstractWebsite

{Two new bis(aryl-imino)-acenaphthene, Ar-BIAN (Ar = 2

Marques, FJ, and CA Coelho. "Testing simultaneously different covariance block diagonal structures–the multi-sample case." Journal of Applied Statistics (2020): 1-20. Abstract
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Coutinho, Mathilda L., João Pedro Veiga, Maria Filomena Macedo, and Ana Zélia Miller. "Testing the Feasibility of Titanium Dioxide Sol-Gel Coatings on Portuguese Glazed Tiles to Prevent Biological Colonization." Coatings. 10 (2020): 1169. Abstract
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