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2018
Gouveia, Nuno D., Duarte M. V. Faria, and António Pinho Ramos. "Assessment of SFRC flat slab punching behaviour – part II: reversed horizontal cyclic loading." Magazine of Concrete Research (2018): 1-17. AbstractWebsite

This paper presents an experimental study of four flat slab specimens subjected to combined vertical and horizontal cyclic loading. Steel fibre-reinforced concrete (SFRC) was used only in the local region of the slab–column connection, while the rest of the slabs were cast using normal concrete. The specimens measured 4·15 m × 1·85 m × 0·15 m and were connected to two steel half columns by 0·25 m × 0·25 m rigid steel plates, prestressed against the slab using steel bolts, to ensure monolithic behaviour. The specimens were tested using an innovative test setup system that accounted for important factors, such as the ability of bending moment redistribution, line of inflection mobility and assured equal vertical displacements at the opposite slab borders, and symmetrical shear forces. Results show that the presence of SFRC in the slab–column connection region is effective in increasing the deformation capacity of slab–column connections, allowing the increase of horizontal drift ratios.

Moniz, António B. "Cenários sobre o futuro do trabalho: avaliação das implicações tecnológicas [Scenarios on the Future of Work: Assessment of technological implications]." Prospetiva Estratégica – Teoria, Métodos e Casos Reais [Strategic Foresight – Theory, Methods and Real cases]. Eds. José Saragoça, Carlos A. Silva, and Joaquim Fialho. Lisboa: Ed. Silabo, 2018. 173-197.
Pessanha, S., C. Fonseca, J. P. Santos, M. L. Carvalho, and A. A. Dias. "Comparison of standard-based and standardless methods of quantification used in X-ray fluorescence analysis: Application to the exoskeleton of clams." X-Ray Spectrom.. 47 (2018): 108-115. Abstract

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Amarante dos Santos, Filipe, Corneliu Cismasiu, and Francisco Braz Fernandes. "Cyclic Instability of Shape-Memory Alloys in Seismic Isolation Systems." International Journal of Structural Glass and Advanced Materials Research (2018): 1-14.
Amarante dos Santos, Filipe, Corneliu Cismasiu, and Francisco Braz Fernandes. "Cyclic Instability of Shape-Memory Alloys in Seismic Isolation Systems." International Journal of Structural Glass and Advanced Materials Research . DOI: 10.3844/sgamrsp.2018. (2018).
Fernandes, Pedro, José Sena-Cruz, José Xavier, Patrícia Silva, Eduardo Pereira, and José Cruz. "Durability of bond in NSM CFRP-concrete systems under different environmental conditions." Composites Part B: Engineering. 138 (2018): 19-34. AbstractWebsite

Abstract This paper addresses the durability of bond between concrete and carbon fibre reinforced polymer (CFRP) strips installed according to the near-surface mounted (NSM) technique (NSM CFRP-concrete systems) under the effects of two main groups of environmental conditions: (i) laboratory-based ageing conditions; (ii) real outdoor ageing conditions. The bond degradation was evaluated by carrying out direct pullout tests on aged specimens that were previously subjected to distinct environmental conditions for different periods of exposure. Moreover, the degradation of the mechanical properties of the involved materials was investigated. The digital image correlation (DIC) method was used to document the evolution of the deformation fields at the surface over the whole region of interest consisting of concrete and epoxy adhesive at the ligament region. This information supported the discussion about the evolution of the bond resistant mechanism developed in \{NSM\} CFRP-concrete specimens during testing, as well as the assessment of the bond quality of the system. In general, the results obtained from the durability tests conducted have shown that the different exposure environments, which may be considered as quite severe, did not result in significant damage on \{NSM\} CFRP-concrete system. The maximum decrease of about 12% on bond strength was obtained for real outdoor environments. Conversely, a maximum increase of 8% on bond strength was obtained on the specimens exposed to the temperature cycles between -15��C and +60��C. \{DIC\} allowed to document the stress transfer mechanisms established between the \{CFRP\} and the concrete substrate, revealing the crack patterns and the influence widths of the \{CFRP\} reinforcement strips, which were shown to be important for avoiding group effect when using multiple parallel strengthening \{CFRP\} strips.

Gouveia, Nuno D., Massimo Lapi, Maurizio Orlando, Duarte M. V. Faria, and António M. P. Ramos. "Experimental and theoretical evaluation of punching strength of steel fiber reinforced concrete slabs." Structural Concrete. 19.1 (2018): 217-229. AbstractWebsite

This paper deals with the experimental and theoretical evaluation of punching shear capacity of steel fiber reinforced concrete (SFRC) slab–column connections. Five experimental specimens with a thickness of 160 mm, different fiber volume contents (0, 1.0, and 1.5%) and different flexural reinforcement ratios (0.75 and 1.5%) have been tested. The experimental results were evaluated using a physical–mechanical model based on the critical shear crack theory (CSCT). The model has given a good approximation of experimental punching shear strengths. In general, tests have highlighted a significant increase in load and deformation capacity of fiber reinforced concrete slab–column connections in comparison with reinforced concrete connections.

Liu, Y., A. S. Palma, T. Feizi, and W. Chai. "Insights Into Glucan Polysaccharide Recognition Using Glucooligosaccharide Microarrays With Oxime-Linked Neoglycolipid Probes." Methods Enzymol.. 598 (2018): 139-167.
Biscaia, Hugo, Carlos Chastre, Cinderela Silva, and Noel Franco. "Mechanical Response of Anchored FRP bonded joints: A Nonlinear Analytical Approach." Mechanics of Advanced Materials and Structures (2018). Abstract

The paper presents a nonlinear analytical solution for the prediction of the full-range debonding response of mechanically-anchored FRP composites from the substrate. The nonlinear analytical approach predicts, for any monotonic loading history or bonded length the relative displacements (or slips) between materials, the strains in the FRP composite, the bond stresses within the interface and the stresses developed in the substrate. The load-slip responses FRP-to-substrate interfaces with a short and a long bonded lengths are motive of analysis and discussion. The solutions obtained from the proposed approach are also compared with other experimental results found in the literature.

Cismasiu, C., J. R. G. Ferreira, and H. B. Rebelo. "Modelação tridimensional de ondas de choque em LS-DYNA." Construção Magazine.86 (2018): 24-28.
Moniz, António B., and Philipp Frey. "Mudança tecnológica: o que a esquerda pode aprender com a Teoría Crítica." Crítica Económica e Social. 17 (2018): 4-13.critica17.pdfWebsite
Gomes, Maria Isabel, Lourde B. Afonso, Nelson Chibeles-Martins, and Joana Fradinho Multi-start local search procedure for the maximum fire risk insured capital problem. International Symposium on Combinatorial Optimization. Marrakech, Marroco, 2018.
Loureiro, LR, DP Sousa, D. Ferreira, W. Chai, L. Lima, C. Pereira, CB Lopes, VG Correia, LM Silva, C. Li, LL Santos, JA Ferreira, A. Barbas, A. S. Palma, C. Novo, and PA Videira. "Novel Monoclonal Antibody L2A5 Specifically Targeting sialyl-Tn and Short Glycans Terminated by alpha-2-6 Sialic Acids." Sci Rep.. 8.1 (2018): 12196.
Casimiro, Ana, Susana Ferreira, and Carlos Florentino. "Principal Schottky bundles over Riemann surfaces (accepted)." Geometriae Dedicata (2018).
Amorim, Mário, Adriana Mar, Fernando Monteiro, Stella Sylaiou, Pedro Pereira, and João Martins. "Smart Tourism Routes Based on Real Time Data and Evolutionary Algorithms." Digital Heritage. Progress in Cultural Heritage: Documentation, Preservation, and Protection. Eds. Marinos Ioannides, Eleanor Fink, Raffaella Brumana, Petros Patias, Anastasios Doulamis, João Martins, and Manolis Wallace. Cham: Springer International Publishing, 2018. 417-426. Abstract

Tourism is an industry that has been growing rapidly in the last few years and it is expected that it will continue to grow. Due to the evolution of technology, mobile applications are being increasingly used in all kinds of industries, being one of them tourism. Presently there are already a few mobile applications used to increase the experience of the user when visiting a place, but these mobile applications lack some important features. This paper describes the development of a mobile application with integrated routing algorithms used to increase the experience of the tourists when visiting the city of Avila, Spain. The tourist will have at their disposal real time information about all the monuments available for visit, a full set of predefined circuits with different visit times and degrees of difficulty and also the possibility to create an optimized or personalized circuit combining the user preferences such as visiting time and number of monuments to visit.

Branco, Paula S., Daniela Peixoto, Margarida Figueiredo, Gabriela Malta, Catarina Roma-Rodrigues, Pedro Viana Batista, Alexandra R. Fernandes, Sónia Barroso, Ana Luisa Carvalho, Carlos A. M. Afonso, and Luísa Maria Ferreira. "Synthesis, cytotoxicity evaluation in human cell lines and in vitro DNA interaction of a hetero arylidene-9(10H)-anthrone." European Journal of Organic Chemistry (2018): n/a–n/a. AbstractWebsite

A new and never yet reported hetero arylidene-9(10H)-anthrone structure (4) was unexpectedly isolated on reaction of 1,2-dimethyl-3-ethylimidazolium iodide (2) and 9-anthracenecarboxaldehyde (3) under basic conditions. Its structure was unequivocally attributed by X-ray crystallography. No cytotoxicity in human healthy fibroblasts and in two different cancer cell lines was observed indicating its applicability in biological systems. Compound 4 interacts with CT-DNA by intercalation between the adjacent base pairs of DNA with a high binding affinity (Kb = 2.0(± 0.20) x 105 M-1) which is 10x higher than that described for doxorubicin (Kb = 3.2 (±0.23) × 104 M-1). Furthermore, compound 4 quenches the fluorescence emission of GelRed-CT-DNA system with a quenching constant (KSV) of 3.3(±0.3) x 103 M-1 calculated by the Stern-Volmer equation.

Moniz, António B., Bettina-Johanna Krings, and Philipp Frey. "Technology and work." TATuP - Zeitschrift für Technikfolgenabschätzung in Theorie und Praxis. 27.3 (2018): 69-70.Website
Ferrás, L., N. Ford, L. Morgado, M. Rebelo, G. H. Mckinley, and J. Nóbrega. "Theoretical and Numerical Analysis of Unsteady Fractional Viscoelastic Flows in Simple Geometries." Computers & Fluids. 174 (2018): 14-33.
Bedon, C., M. Arrigoni, F. Santos, and L. Figuli. "Advancements in design and analysis of protective structures." Advances in Civil Engineering. 2018 (2018). AbstractWebsite
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Gomes, Ana Sara, Filipa Trovão, Benedita Andrade Pinheiro, Filipe Freire, Sara Gomes, Carla Oliveira, Lucília Domingues, Maria João Romão, Lucília Saraiva, and Ana Luísa Carvalho. "The Crystal Structure of the R280K Mutant of Human p53 Explains the Loss of DNA Binding." International Journal of Molecular Sciences. 19 (2018). AbstractWebsite

The p53 tumor suppressor is widely found to be mutated in human cancer. This protein is regarded as a molecular hub regulating different cell responses, namely cell death. Compelling data have demonstrated that the impairment of p53 activity correlates with tumor development and maintenance. For these reasons, the reactivation of p53 function is regarded as a promising strategy to halt cancer. In the present work, the recombinant mutant p53R280K DNA binding domain (DBD) was produced for the first time, and its crystal structure was determined in the absence of DNA to a resolution of 2.0 Å. The solved structure contains four molecules in the asymmetric unit, four zinc(II) ions, and 336 water molecules. The structure was compared with the wild-type p53 DBD structure, isolated and in complex with DNA. These comparisons contributed to a deeper understanding of the mutant p53R280K structure, as well as the loss of DNA binding related to halted transcriptional activity. The structural information derived may also contribute to the rational design of mutant p53 reactivating molecules with potential application in cancer treatment.

Biscaia, H. C., N. Franco, and C. Chastre. "Development of a simple bond-slip model for joints monitored with the DIC technique." Archives of Civil and Mechanical Engineering. 18 (2018): 1535-1546. AbstractWebsite

The monitoring of structures has undergone important advances with the improvements of digital cameras available on the market. Thus, the Digital Image Correlation (DIC) technique has become a viable way of studying engineering problems. Recently it has been used in the debonding failure process between the reinforcement and the substrate. The methods or methodologies that should be followed to obtain the results associated to the debonding phenomenon using the DIC technique need to be better understood and studies on this topic are scarce. The present work therefore proposes a new and inexpensive method to monitor the interfacial behaviour between a reinforcement material and a substrate by combining the use of the DIC technique and a simplified nonlinear bond-slip model. For the validation of the proposed method, a series of single-lap shear tests with a sufficient long bond length carried out by the authors are used. Based on the slip distribution obtained from the DIC technique, it was found that a third-degree polynomial function can be used to approximate the interfacial bond-slip curve of the joint. The validation of the model is made with several analytical solutions using the proposed bond-slip model. © 2018 Politechnika Wrocławska

Franco, N., H. Biscaia, and C. Chastre. "Experimental and numerical analyses of flexurally-strengthened concrete T-beams with stainless steel." Engineering Structures. 172 (2018): 981-996. AbstractWebsite

This work presents the results and the main conclusions of a series of experimental tests carried out to evaluate the efficiency of post-installed stainless steel reinforcement on the flexural strengthening of Reinforced Concrete (RC) T-beams when the bonding techniques EBR (Externally Bonded Reinforcement), NSM (Near Surface Mounted) and MA-EBR (EBR with Mechanical Anchors) are used. The RC T-beams were also modelled using a commercial Finite Element (FE) software in order to predict their behaviour until the rupture. For this purpose, a set of single-lap shear tests were also carried out to evaluate the local bond-slip relationships developed within the Stainless Steel (SS)-to-concrete interface. Due to the experimental bond-slip relationships, the numerical simulations were able to predict, with good accuracy, the different behaviours of the RC T-beams until their rupture. Moreover, the different rupture modes observed on all the RC T-beams herein tested were very well estimated by the numerical analyses. The tests of the RC T-beams showed that all the strengthening techniques allowed their flexural stiffness to be increased. Nevertheless, the RC T–beams strengthened with the EBR and NSM techniques had premature ruptures, i.e. the rupture in the RC T-beams occurred even before the yielding of their steel reinforcements. The RC T-beam strengthened with the MA-EBR technique showed good ductility and the highest load bearing capacity, which means that the MA-EBR technique is the best bonding technique herein used. © 2018 Elsevier Ltd

Pereira, L., A. C. Freire, M. Sá da Costa, V. Antunes, L. Quaresma, and R. Micaelo. "Experimental study of the effect of filler on the ductility of filler-bitumen mastics." Construction and Building Materials. 189 (2018): 1045-1053. AbstractWebsite
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Zarrouk, Olfa, Carla Pinheiro, {Chandra S. } Misra, Victoria Fernández, and {Maria M. } Chaves. "Fleshy Fruit Epidermis is a Protective Barrier Under Water Stress." Water Scarcity and Sustainable Agriculture in Semiarid Environment. Netherlands: Elsevier, 2018. 507-533. Abstract

Fruits may be exposed to several unfavorable mechanical, climatic, and biological factors during ripening. Harvest and storage also challenge fruit integrity before fruits reach the consumer. In order to preserve fruit properties/characteristics it is essential that the structural and chemical integrity of the cuticle is maintained throughout fruit development and expansion. In addition, cuticles serve as protection against multiple biotic and abiotic stress factors and primarily act as a barrier to prevent water loss. Despite the important functions attributed to the cuticle, little is known about fruit cuticle biosynthesis and assembly, which is highly relevant when coping with adverse conditions. Presently, drought and heat pose severe constraints to the fruit industry via penalties in yield and fruit quality. Available climate change models suggest a scenario in which the impact of these environmental factors will negatively affect the fruit industry. A comprehensive understanding of the physiological and biochemical effects of limited water availability on fruit traits is a prerequisite for implementing breeding and knowledge-based strategies that enhance fruit crop tolerance to limited water availability. To address some of these questions, this chapter aimed to revise the existing information on cuticle physiology, composition, structure, and properties, also considering its impact on fruit under abiotic stresses, with an emphasis on water deficit. We also address the recent molecular progress in cuticle biosynthesis pathways and highlight some of the major research questions that will have to be dealt with in the future.

Vitor Rosa, Ana Gaspari, Filipe Folgosa, Cristina M. Cordas, Pedro Tavares, Teresa Santos-Silva, Sonia Barroso, and Teresa Aviles. "Imine Ligands Based on Ferrocene: Synthesis{,} Structural and Mossbauer Characterization and Evaluation as Chromogenic and Electrochemical Sensors for Hg+2." New J. Chem. (2018): -. AbstractWebsite

The compounds 1-naphthyliminoferrocene{,} 1{,} and 2-methyl-1-naphthyliminoferrocene{,} 2{,} were prepared by the reaction of ferrocenecarboxaldehyde and the corresponding amine{,} 1-naphthylamine and 2-methyl-1-naphthylamine with one drop of pyrrolidine as catalyst{,} in CH2Cl2{,} under inert atmosphere. The compounds were fully characterized by elemental analyses{,} matrix-assisted laser desorption/ionization - time-of-flight mass spectrometry (MALDI-TOF){,} FT-IR{,} 1H and 13C NMR as well as two-dimensional{,} NOESY{,} COSY and HSQC{,} NMR spectroscopy. Mossbauer spectroscopic studies were performed to characterize the iron species in both compounds. The solid-state molecular structures of compounds 1 and 2 were determined by single crystal X-ray diffraction. Analysis of the electrochemical behaviour of complexes 1 and 2 was performed by cyclic and square wave voltammetry. Compounds 1 and 2 were tested as chromogenic and electrochemical sensors for Hg2+.