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2017
Araújo, Andreia, Ana Pimentel, Maria João Oliveira, Manuel J. Mendes, Ricardo Franco, Elvira Fortunato, Hugo Águas, and Rodrigo Martins. "Direct growth of plasmonic nanorod forests on paper substrates for low-cost flexible 3D SERS platforms." Flexible and Printed Electronics. 2 (2017): 014001. Abstract
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Peres, Ricardo Silva, Andre Dionisio Rocha, Andre Coelho, and Jose Barata Oliveira. "A Highly Flexible, Distributed Data Analysis Framework for Industry 4.0 Manufacturing Systems." Service Orientation in Holonic and Multi-Agent Manufacturing. Springer, Cham, 2017. 373-381. Abstract
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Otrelo-Cardoso, A. R., R. R. Nair, MAS Correia, R. S. C. Cordeiro, A. Panjkovich, D. I. Svergun, T. Santos-Silva, and M. G. Rivas. "Highly selective tungstate transporter protein TupA from Desulfovibrio alaskensis G20." Scientific Reports. 7 (2017). Abstract
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Fernandes, Susete N., Pedro L. Almeida, Nuno Monge, Luis E. Aguirre, Dennys Reis, Cristiano LP de Oliveira, António MF Neto, Pawel Pieranski, and Maria H. Godinho. "Mind the Microgap in Iridescent Cellulose Nanocrystal Films." Advanced Materials. 29.2 (2017). Abstract
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Lourenço, P., B. J. Guerreiro, P. Batista, P. Oliveira, and C. Silvestre. "Sensing and Control for Autonomous Vehicles: Applications to Land, Water and Air Vehicles." Eds. Thor I. Fossen, Kristin Y. Pettersen, and Henk Nijmeijer. Springer, 2017. 121-141. Abstract
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Lourenço, P., B. J. Guerreiro, P. Batista, P. Oliveira, and C. Silvestre. "Sensing and Control for Autonomous Vehicles: Applications to Land, Water and Air Vehicles." Eds. Thor I. Fossen, Kristin Y. Pettersen, and Henk Nijmeijer. Springer, 2017. 121-141. Abstract
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Dardouri, Maïssa, João Paulo Borges, and Amel Dakhlaoui Omrani. "Tailoring the morphology of hydroxyapatite particles using a simple solvothermal route." Ceramics International. 43.4 (2017): 3784-3791. Abstract
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Pimentel, A., A. Araújo, B. J. Coelho, D. Nunes, M. J. Oliveira, MJ Mendes, H. Águas, R. Martins, and E. Fortunato. "{3D ZnO/Ag surface-enhanced Raman scattering on disposable and flexible cardboard platforms}." Materials. 10 (2017). Abstract

© 2017 by the authors. In the present study, zinc oxide (ZnO) nanorods (NRs) with a hexagonal structure have been synthesized via a hydrothermal method assisted by microwave radiation, using specialized cardboard materials as substrates. Cardboard-type substrates are cost-efficient and robust paper-based platforms that can be integrated into several opto-electronic applications for medical diagnostics, analysis and/or quality control devices. This class of substrates also enables highly-sensitive Raman molecular detection, amiable to several different operational environments and target surfaces. The structural characterization of the ZnO NR arrays has been carried out by X-ray diffraction (XRD), scanning electron microscopy (SEM) and optical measurements. The effects of the synthesis time (5-30 min) and temperature (70-130 °C) of the ZnO NR arrays decorated with silver nanoparticles (AgNPs) have been investigated in view of their application for surface-enhanced Raman scattering (SERS) molecular detection. The size and density of the ZnO NRs, as well as those of the AgNPs, are shown to play a central role in the final SERS response. A Raman enhancement factor of 7 × 105was obtained using rhodamine 6 G (RG6) as the test analyte; a ZnO NR array was produced for only 5 min at 70 °C. This condition presents higher ZnO NR and AgNP densities, thereby increasing the total number of plasmonic "hot-spots", their volume coverage and the number of analyte molecules that are subject to enhanced sensing.

Otero, V., M. F. Campos, JV Pinto, M. Vilarigues, L. Carlyle, and M. J. Melo. "{Barium, zinc and strontium yellows in late 19th-early 20th century oil paintings}." Heritage Science. 5 (2017). Abstract

© 2017 The Author(s). This work focuses on the study of the 19th century yellow chromate pigments based on barium (BaCrO4), zinc (4ZnCrO4K2O3H2O) and strontium (SrCrO4). These pigments, which are reported to shift in hue and darken, have been found in 19th century artworks. A better understanding of their historic manufacture will contribute to the visual/chemical interpretation of change in these colours. Research was carried out on the Winsor & Newton (W&N) 19th century archive database providing a unique insight into their manufacturing processes. One hundred and three production records were found, 69% for barium, 25% for zinc and 6% for strontium chromates, mainly under the names Lemon, Citron and Strontian Yellow, respectively. Analysis of the records shows that each pigment is characterised by only one synthetic pathway. The low number of records found for the production of strontium chromate suggests W&N was not selling this pigment formulation on a large scale. Furthermore, contrary to what the authors have discovered for W&N chrome yellow pigments, extenders were not added to these pigment formulations, most probably due to their lower tinting strength (TS). The latter was calculated in comparison to pure chrome yellow (PbCrO4, 100% TS) resulting in 92% for barium, 65% for zinc potassium and 78% for strontium chromate pigments. This indicates that W&N was probably using extenders primarily to adjust pigment properties and not necessarily as a means to reduce their costs. Pigment reconstructions following the main methods of synthesis were characterised by complementary analytical techniques: Fibre optic reflectance spectroscopy, X-ray diffraction, micro-Raman and micro-Fourier transform infrared spectroscopies. These pigments can be clearly distinguished on the basis of their infrared CrO42-asymmetric stretching fingerprint profile (between 1000 and 700 cm-1) and of their Raman CrO42-stretching bands (850-950 cm-1). This enabled their identification in historic paint samples: a tube of late 19th century W&N Lemon Yellow oil paint and micro-samples from paintings by three Portuguese painters, António Silva Porto (1850-1893), João Marques de Oliveira (1853-1927) and Amadeo de Souza-Cardoso (1887-1918). The good correlation found between the reconstructions and historic samples validates their use as reference materials for future photochemical studies.

Araújo, A., A. Pimentel, M. J. Oliveira, MJ Mendes, R. Franco, E. Fortunato, H. Águas, and R. Martins. "{Direct growth of plasmonic nanorod forests on paper substrates for low-cost flexible 3D SERS platforms}." Flexible and Printed Electronics. 2 (2017). Abstract

Paper substrates, coated with ZnO nanorods (NRs) decorated with Ag nanoparticles (NPs), allowed the production of inexpensive, highly-performing and extremely reproducible three-dimensional (3D) SERS platforms. The ZnO NRs were synthesized by a simple, fast and low-temperature hydrothermal method assisted by microwave radiation and made SERS-active by decorating them with a dense array of silver nanoparticles deposited via a single-step thermal evaporation technique. Using Rhodamine 6G (R6G) as a probe molecule, with an amount down to 10-9 M, the SERS substrates allowed a Raman signal enhancement of 107. The contribution of the inter-Ag-NPs gaps for 3D geometry, ZnO NRs orientation and the large sensing area allowed by theNRscaffolds, were determinant factors for the significant Raman enhancement observed. The results demonstrate that plasmonic nanorod forests, covered with Ag NPs, are efficient SERS substrates with the advantages of being recyclable, flexible, lightweight, portable, biocompatible and extremely low-cost.

Barros, A. A., C. Oliveira, A. J. Ribeiro, R. Autorino, R. L. Reis, A. R. C. Duarte, and E. Lima. "{In vivo assessment of a novel biodegradable ureteral stent}." World Journal of Urology (2017). Abstract

© 2017 Springer-Verlag GmbH Germany, part of Springer Nature Purpose: To perform an in vivo assessment of a newly developed biodegradable ureteral stent (BUS) produced with natural-based polymers. Methods: The BUS is based on a patented technology combining the injection process with the use of supercritical fluid technology. Study was conducted at ICVS—University of Minho (Braga, Portugal) and a total of ten domestic pigs were used. In seven animals, the experimental BUS stent was inserted, whereas in the remaining a commercially available stent was used (6-Fr Biosoft ® duo stents, Porges Coloplast, Denmark). Post-stenting intravenous pyelogram was used to evaluate the degree of hydronephrosis. The in vivo stent degradation was measured as function of the weight loss. Moreover, the tensile properties of the BUS were tested during in vivo degradation. After maximum 10 days, animals were killed and necropsy was performed. Tissues were compared between the stented groups as well as between the non-stented contralateral ureters and stented ureters in each group. Biocompatibility was assessed by histopathological grading. Results: In all cases, the BUS was only visible during the first 24 h on X-ray, and in all cases the BUS was completely degraded in urine after 10 days, as confirmed on necropsy. During the degradation process, the mechanical properties of the BUS decreased, while the commercial ureteral stents remained constant. At all time-points after stent insertion, the level of hydronephrosis was minimal. Overall, animals stented with BUS had an average grade of hydronephrosis which was lower compared to the controls. The BUS showed better pathological conditions, and hence better biocompatibility when compared with commercial stents. Conclusions: Notwithstanding the limitations of the present study, the in vivo testing of our novel natural origin polymer-based BUS suggests this device to feature homogeneous degradation, good urine drainage, and high biocompatibility. Next steps will be to increase its stability, and to improve the radiopacity without compromising its degradation. Ultimately, clinical studies will be required to determine the safety and feasibility of its use in humans.

Barros, A. A., C. Oliveira, R. L. Reis, E. Lima, and A. R. C. Duarte. "{In Vitro and Ex Vivo Permeability Studies of Paclitaxel and Doxorubicin From Drug-Eluting Biodegradable Ureteral Stents}." Journal of Pharmaceutical Sciences. 106 (2017). Abstract

© 2017 American Pharmacists Association® A drug-eluting biodegradable ureteral stent (BUS) has been developed as a new approach for the treatment of urothelial tumors of upper urinary tract cancer. In a previous work, this system has proven to be a good carrier for anticancer drugs as a potential effective and sustainable intravesical drug delivery system. BUS has revealed to reduce in 75{%} the viability of human urothelial cancer cells (T24) after 72 h of contact and demonstrated minimal cytotoxic effect on human umbilical vein endothelial cells (HUVECs) which were used as a control. In this work, we studied the permeability of the anticancer drugs, such as paclitaxel and doxorubicin, alone or released from the BUS developed. We used 3 different membranes to study the permeability: polyethersulfone (PES) membrane, HUVECs cell monolayer, and an ex vivo porcine ureter. The ureter thickness was measured (864.51 $μ$m) and histological analysis was performed to confirm the integrity of urothelium. Permeability profiles were measured during 8 h for paclitaxel and doxorubicin. The drugs per se have shown to have a different profile and as expected, increasing the complexity of the membrane to be permeated, the permeability decreased, with the PES being more permeable and the ex vivo ureter tissue being less permeable. The molecular weight has also shown to influence the permeability of each drug and a higher percentage for doxorubicin (26{%}) and lower for paclitaxel (18{%}) was observed across the ex vivo ureter. The permeability (P), diffusion (D), and partition (K d ) coefficients of paclitaxel and doxorubicin through the permeable membranes were calculated. Finally, we showed that paclitaxel and doxorubicin drugs released from the BUS were able to remain in the ex vivo ureter and only a small amount of the drugs can across the different permeable membranes with a permeability of 3{%} for paclitaxel and 11{%} for doxorubicin. The estimated amount of paclitaxel that remains in the ex vivo ureter tissue is shown to be effective to affect the cancer cell and not affect the noncancer cells.

Otero, V., J. V. V. Pinto, L. Carlyle, M. Vilarigues, M. Cotte, and M. J. J. Melo. "{Nineteenth century chrome yellow and chrome deep from Winsor & NewtonTM}." Studies in Conservation. 62 (2017): 123-149. AbstractWebsite

The Winsor & NewtonTM (W&N) nineteenth century archive database includes digitised images of hand- written instructions and workshop notes for the manufacture of their artists' materials. For the first time, all 183 production records for yellow lead chromate pigments were studied and evaluated. They revealed that W&N produced essentially three pigment types: lemon/pale based on mixed crystals of lead chromate and lead sulphate [Pb(Cr,S)O4]; middle on pure monoclinic lead chromate [PbCrO4]; and deep that contains the latter admixed with basic lead chromate [Pb2CrO5]; accounting for 53, 22, and 21% of the production, respectively. Production records for primrose (4%) were also included since the formulation results in mixed crystals with a high percentage of lead sulphate, which, according to the literature, leaves it more prone to degradation. Each pigment type is characterised by only one or two main synthetic pathways; process variations reveal a systematic and thorough search for a high-quality durable product. A comparison of the chemical composition of pigment reconstructions with early W&N oil paint tubes showed that their records entitled ‘pale' and ‘lemon' correlated with the pigment in their tube labelled chrome yellow and, ‘middle' and ‘deep' with the label chrome deep. Lemon and middle pigment formulations were made into oil paints to assess their relative photo-stability. The degradation process was followed by colorimetry and was studied by synchrotron radiation-based techniques. Based on the X-ray absorption spectroscopy data, the possibility for creating a stability index for chrome yellows is discussed. Keywords:

Lourenço, P., B. J. Guerreiro, P. Batista, P. Oliveira, and C. Silvestre. "{Uncertainty Characterization of the Orthogonal Procrustes Problem with Arbitrary Covariance Matrices}." Pattern Recognition. 61 (2017): 210-220. Abstract
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Lourenço, P., B. J. Guerreiro, P. Batista, P. Oliveira, and C. Silvestre. "{Uncertainty Characterization of the Orthogonal Procrustes Problem with Arbitrary Covariance Matrices}." Pattern Recognition. 61 (2017): 210-220. Abstract
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2016
Ito, Y., T. Tochio, H. Ohashi, M. Yamashita, S. Fukushima, M. Polasik, K. Słabkowska, Ł. Syrocki, E. Szymańska, J. Rzadkiewicz, P. Indelicato, J. P. Marques, M. C. Martins, J. P. Santos, and F. Parente. "Kα1,2x-ray linewidths, asymmetry indices, and [KM]shake probabilities in elements Ca to Ge and comparison with theory for Ca, Ti, and Ge." Physical Review A. 94 (2016): 042506-11. AbstractWebsite
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Lorenz, M., et al. "{The 2016 oxide electronic materials and oxide interfaces roadmap}." Journal of Physics D: Applied Physics. 49 (2016): 433001. AbstractWebsite

Oxide electronic materials provide a plethora of possible applications and offer ample opportunity for scientists to probe into some of the exciting and intriguing phenomena exhibited by oxide systems and oxide interfaces. In addition to the already diverse spectrum of properties, the nanoscale form of oxides provides a new dimension of hitherto unknown phenomena due to the increased surface-to-volume ratio. Oxide electronic materials are becoming increasingly important in a wide range of applications including transparent electronics, optoelectronics, magnetoelectronics, photonics, spintronics, thermoelectrics, piezoelectrics, power harvesting, hydrogen storage and environmental waste management. Synthesis and fabrication of these materials, as well as processing into particular device structures to suit a specific application is still a challenge. Further, characterization of these materials to understand the tunability of their properties and the novel properties that evolve due to their nanostructured nature is another facet of the challenge. The research related to the oxide electronic field is at an impressionable stage, and this has motivated us to contribute with a roadmap on 'oxide electronic materials and oxide interfaces'. This roadmap envisages the potential applications of oxide materials in cutting edge technologies and focuses on the necessary advances required to implement these materials, including both conventional and novel techniques for the synthesis, characterization, processing and fabrication of nanostructured oxides and oxide-based devices. The contents of this roadmap will highlight the functional and correlated properties of oxides in bulk, nano, thin film, multilayer and heterostructure forms, as well as the theoretical considerations behind both present and future applications in many technologically important areas as pointed out by Venkatesan. The contributions in this roadmap span several thematic groups which are represented by the following authors: novel field effect transistors and bipolar devices by Fortunato, Grundmann, Boschker, Rao, and Rogers; energy conversion and saving by Zaban, Weidenkaff, and Murakami; new opportunities of photonics by Fompeyrine, and Zuniga-Perez; multiferroic materials including novel phenomena by Ramesh, Spaldin, Mertig, Lorenz, Srinivasan, and Prellier; and concepts for topological oxide electronics by Kawasaki, Pentcheva, and Gegenwart. Finally, Miletto Granozio presents the European action 'towards oxide-based electronics' which develops an oxide electronics roadmap with emphasis on future nonvolatile memories and the required technologies. In summary, we do hope that this oxide roadmap appears as an interesting up-to-date snapshot on one of the most exciting and active areas of solid state physics, materials science, and chemistry, which even after many years of very successful development shows in short intervals novel insights and achievements.

Oliveira, João P., and João Goes. "Advanced Amplification Techniques for Nanoscale CMOS in the Context of IoT Node Sensors." 22nd International Conference Mixed Design of Integrated Circuits & Systems (MIXDES’16). Lodz, Poland: IEEE, 2016.
Tsoukantas, Spyros, Giandomenico Toniolo, Stefano Pampanin, S. K. Ghosh, Larbi Sennour, Thomas D’Arcy, Saha Sthaladipti, Marco Menegotto, Şevket Özden, Válter Lúcio, Carlos Chastre, Stefanos Dritsos, Ioannis Psycharis, Tryfon Topintzis, Georgia Kremmyda, David Fernández-Ordóñez, André de Chefdebien, Simon Hughes, and Lasse Rajala fib Bulletin 78. Precast-concrete buildings in seismic areas. fib bulletin. Lausanne: International Federation for Structural Concrete (fib), 2016. Abstractfib_bulletin78.jpgWebsite

This document has a broad scope and is not focussed on design issues. Precast construction under seismic conditions is treated as a whole. The main principles of seismic design of different structural systems, their behavior and their construction techniques are presented through rules, construction steps and sequences, procedures, and details that should lead to precast structures built in seismic areas complying with the fundamental performance requirements of collapse prevention and life safety in major earthquakes and limited damage in more frequent earthquakes.The content of this document is largely limited to conventional precast construction and, although some information is provided on the well-known “PRESSS technology” (jointed ductile dry connections), this latter solution is not treated in detail in this document.The general overview, contained in this document, of alternative structural systems and connection solutions available to achieve desired performance levels, intends to provide engineers, architects, clients, and end-users (in general) with a better appreciation of the wide range of applications that modern precast concrete technology can have in various types of construction from industrial to commercial as well as residential. Lastly, the emphasis on practical aspects, from conceptual design to connection detailing, aims to help engineers to move away from the habit of blindly following prescriptive codes in their design, but instead go back to basic principles, in order to achieve a more robust understanding, and thus control, of the seismic behaviour of the structural system as a whole, as well as of its components and individual connections.

Lapi, Massimo, Daniele Martini, Emilio Zagli, Maurizio Orlando, Antonio Ramos, and Paolo Spinelli. "Comparison of flat slab strengthening techniques against punching-shear." Proceedings of The New Boundaries of Structural Concrete 2016, NBSC2016, Italy ACI Chapter. Capri, Italy: Italy ACI Chapter, 2016. Abstract

Punching-shear capacity of slab-column connections in existing R/C structures may be inadequate to bear design loads, so strengthening works are required. The lack of punching resistance may be due to detailing, design or building errors; in other cases, such lack is due to a change of use, which requires an increase of resistance. Different techniques have been developed for strengthening R/C slabs against punching: enlargement of the support, gluing external fibre reinforced polymers or casting a bonded concrete overlay (BCO) on the slab's top surface, insertion of post-installed steel bolts, application of fibre reinforced polymers cords as shear reinforcement. In the paper, the authors apply the Critical Shear Crack Theory (CSCT) to all of these techniques and evaluate their efficacy with reference to a case study.

Fernandes, Miguel D., Luis B. Oliveira, João Goes, and João P. Oliveira Design of a Low Phase Error Multiphase Clock Generator for Modern Wideband Receivers. IEEE 12th Conference on PhD Research in Microelectronics and Electronics (PRIME 2016). Lisbon, Portugal: IEEE, 2016.
Dias, J. P., M. FIgueira, and F. Oliveira. "Existence and linearized stability of solitary waves for a quasilinear Benney system." Proceedings of the Royal Society of Edinburgh. 146-03 (2016): 547-564.Website
Śniatała, Paweł, Andrzej Handkiewicz, João Goes, Nuno Paulino, and João Pedro Oliveira Fully differential sigma-delta modulator structure for current-mode sensors. International Conference on Signals and Electronic Systems (ICSES’16). Krakow, Poland: IEEE, 2016.
Oliveira, F., and H. Tavares. "Ground States for a nonlinear Schrödinger system with sublinear coupling terms." Advanced Nonlinear Studies. 16 (2016): 381-387.Website