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2016
b c b c b c b c Liu, A.a b c, Liu Zhu Zhu Fortunato Martins Shan G. a C. a. "Solution-Processed Alkaline Lithium Oxide Dielectrics for Applications in n- and p-Type Thin-Film Transistors." Advanced Electronic Materials. 2 (2016). AbstractWebsite

High-k alkaline lithium oxide (LiOx) thin films are fabricated by spin-coating method. The LiOx thin films are annealed at different temperatures and characterized by various techniques. An optimized LiOx dielectric is achieved at an annealing temperature of 300 °C and exhibits wide bandgap of ≈5.5 eV, smooth surface, relatively permittivity of ≈6.7, and low leakage current density. The as-fabricated LiOx thin films are integrated, as gate dielectrics, in both n-channel indium oxide (In2O3) and p-channel cupric oxide (CuO) transistors. The optimized In2O3/LiOx thin-film transistor (TFT) exhibits high performance and high stability, such as Ion/Ioff of 107, electron mobility of 5.69 cm2 V−1 s−1, subthreshold swing of 70 mV dec−1, negligible hysteresis, and threshold voltage shift of 0.1 V under bias stress for 1.5 h. Meanwhile, the p-channel CuO TFT based on LiOx dielectric shows high Ion/Ioff of 105 and hole mobility of 1.72 cm2 V−1 s−1. All the electrical performances are achieved at an ultra-low operating voltage of 2 V. Considering the simple procedure, the moderate annealing temperature, and the low power consumption merits, these outstanding characteristics represent a significant advance toward the development of battery compatible and portable electronics. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim

Bernardo, G. M. S., F. R. Damásio, T. A. N. Silva, and M. A. R. Loja A study on the structural behaviour of FGM plates static and free vibrations analyses. Vol. 136. Composite Structures, 136., 2016. Abstract
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Soares, Paula I. P., Diana Machado, César Laia, Laura CJ Pereira, Joana T. Coutinho, Isabel M. M. Ferreira, Carlos M. M. Novo, and João Paulo Borges. "Thermal and magnetic properties of chitosan-iron oxide nanoparticles." Carbohydrate polymers. 149 (2016): 382-390. Abstract
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Tolstogouzov, Alexander, Hugo Aguas, Rachid Ayouchi, Sergey F. Belykh, Fábio Luís, Gennady P. Gololobov, Augusto M. C. Moutinho, Reinhard Schwarz, Dmitry V. Suvorov, and Orlando M. N. D. Teodoro. "Vacuum solid-state ion-conducting silver source for application in field emission electric propulsion systems." Vacuum. 131 (2016): 252-258. Abstract
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Barros, A. A., S. Browne, C. Oliveira, E. Lima, A. R. C. Duarte, K. E. Healy, and R. L. Reis. "{Drug-eluting biodegradable ureteral stent: New approach for urothelial tumors of upper urinary tract cancer}." International Journal of Pharmaceutics. 513 (2016). Abstract

© 2016 Elsevier B.V. Upper urinary tract urothelial carcinoma (UTUC) accounts for 5–10{%} of urothelial carcinomas and is a disease that has not been widely studied as carcinoma of the bladder. To avoid the problems of conventional therapies, such as the need for frequent drug instillation due to poor drug retention, we developed a biodegradable ureteral stent (BUS) impregnated by supercritical fluid CO 2 (scCO 2 ) with the most commonly used anti-cancer drugs, namely paclitaxel, epirubicin, doxorubicin, and gemcitabine. The release kinetics of anti-cancer therapeutics from drug-eluting stents was measured in artificial urine solution (AUS). The in vitro release showed a faster release in the first 72 h for the four anti-cancer drugs, after this time a plateau was achieved and finally the stent degraded after 9 days. Regarding the amount of impregnated drugs by scCO 2 , gemcitabine showed the highest amount of loading (19.57 $μ$g drug /mg polymer: 2{%} loaded), while the lowest amount was obtained for paclitaxel (0.067 $μ$g drug /mg polymer : 0.01{%} loaded). A cancer cell line (T24) was exposed to graded concentrations (0.01–2000 ng/ml) of each drugs for 4 and 72 h to determine the sensitivities of the cells to each drug (IC 50 ). The direct and indirect contact study of the anti-cancer biodegradable ureteral stents with the T24 and HUVEC cell lines confirmed the anti-tumoral effect of the BUS impregnated with the four anti-cancer drugs tested, reducing around 75{%} of the viability of the T24 cell line after 72 h and demonstrating minimal cytotoxic effect on HUVECs.

Morawiec, S., J. Holovský, MJ Mendes, M. Müller, K. Ganzerová, A. Vetushka, M. Ledinský, F. Priolo, A. Fejfar, and I. Crupi. "{Experimental quantification of useful and parasitic absorption of light in plasmon-enhanced thin silicon films for solar cells application}." Scientific Reports (2016). AbstractWebsite
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Antognini, A., K. Schuhmann, F. D. Amaro, P. Amaro, M. Abdou-Ahmed, F. Biraben, T. L. 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. W. Liu, J. Machado, C. M. B. Monteiro, F. Mulhauser, F. Nez, J. P. Santos, J. M. F. dos Santos, C. I. Szabo, D. Taqqu, J. F. C. A. Veloso, A. Voss, B. Weichelt, and R. Pohl. "{Experiments towards resolving the proton charge radius puzzle}." Vol. 113. EPJ Web of Conferences, 2016. 01006. Abstract
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Lyubchyk, A., A. Vicente, P. U. Alves, B. Catela, B. Soule, T. Mateus, MJ Mendes, H. Águas, E. Fortunato, and R. Martins. "{Influence of post-deposition annealing on electrical and optical properties of ZnO-based TCOs deposited at room temperature}." Physica Status Solidi (A) Applications and Materials Science. 213 (2016). Abstract

© 2016 WILEY-VCH Verlag GmbH {&} Co. KGaA, Weinheim The post-deposition modification of ZnO-based transparent conductive oxides (TCOs) can be the key to produce thin films with optoelectronic properties similar to indium tin oxide (ITO), but at a much lower cost. Here, we present electro-optical results achieved for post-deposition annealing of Al–Zn–O (AZO), AZO:H, Ga–Zn–O:H (GZO:H), and Zn–O:H (ZNO:H) thin films deposited by RF sputtering at room temperature. These studies comprise results of thermal annealing at atmospheric pressure, vacuum, forming gas, H2and Ar atmospheres, and H2and Ar plasmas, which lead to significant enhancement of their electro-optical properties, which are correlated to morphological and structural improvements. The post-deposition annealing leads to an enhancement in resistivity above 40{%} for AZO, AZO:H, and GZO:H, reaching $\rho$ ≈ 2.6–3.5 × 10−4$Ømega$cm, while ZnO:H showed a lower improvement of 13{%}. The averaged optical transmittance in the visible region is about 89{%} for the investigated TCOs. Such results match the properties of state-of-art ITO ($\rho$ ≈ 10−4$Ømega$cm and transmittance in VIS range of 90{%}) employing much more earth-abundant materials.

Lyubchyk, Andriy, António Vicente, Bertrand Soule, Pedro Urbano Alves, Tiago Mateus, Manuel J. Mendes, Hugo Águas, Elvira Fortunato, and Rodrigo Martins. "{Mapping the Electrical Properties of ZnO-Based Transparent Conductive Oxides Grown at Room Temperature and Improved by Controlled Postdeposition Annealing}." Advanced Electronic Materials. 2 (2016): 1500287. AbstractWebsite

Indium tin oxide (ITO) is the current standard state-of-the-art transparent conductive oxide (TCO), given its remarkable optical and electrical properties. However, the scarcity of indium carries an important drawback for the long-term application due to its intensive use in many optoelectronic devices such as displays, solar cells, and interactive systems. Zinc oxide-based TCOs can be a cost-effective and viable alternative, but the limitations imposed by their transmittance versus resistivity tradeoff still keep them behind ITO. In this work, an in-depth study of the structural and compositional material changes induced by specific postannealing treatments is presented, based on aluminum zinc oxide (AZO) and hydrogenated AZO (AZO:H) thin films grown by rf-magnetron sputtering at room temperature that allows an extensive understanding of the films' electrical/structural changes and the ability to tune their physical parameters to yield increasingly better performances, which put them in line with the best ITO quality standards. The present investigation comprises results of thermal annealing at atmospheric pressure, vacuum, forming gas, H2 and Ar atmospheres and plasmas. Overall the study being performed leads to a decrease in resistivity above 40{%}, reaching $\rho$ ≈ 3 × 10−4 $Ømega$ cm, with an average optical transmittance in the visible region around 88{%}. Such results are equivalent to the properties of state-of-the-art ITO.

Lopes, A., A. Gabriel, J. Machado, P. Ribeiro, R. Gomes, João M. P. Coelho, C. O. Silva, C. P. Reis, J. P. Santos, and P. Vieira. "{Multiple Source Phototherapy in Breast Cancer: A Viability Study}." 9th International Conference on Biomedical Electronics and Devices. SCITEPRESS - Science and and Technology Publications, 2016. 247-250. Abstract
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Reifarth, R., et al. "{Nuclear astrophysics with radioactive ions at FAIR}." Vol. 665. Journal of Physics: Conference Series, 2016. 012044. Abstract
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Lourenço, P., B. J. Guerreiro, P. Batista, P. Oliveira, and C. Silvestre. "{Simultaneous Localization and Mapping for Aerial Vehicles: a 3-D sensor-based GAS filter}." Autonomous Robots. 40 (2016): 881-902. Abstract
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Lourenço, P., B. J. Guerreiro, P. Batista, P. Oliveira, and C. Silvestre. "{Simultaneous Localization and Mapping for Aerial Vehicles: a 3-D sensor-based GAS filter}." Autonomous Robots. 40 (2016): 881-902. Abstract
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2015
Pinho, S. T. R., P. Rodrigues, R. F. S. Andrade, H. Serra, J. S. Lopes, and M. G. M. Gomes. "Impact of tuberculosis treatment length and adherence under different transmission intensities." THEORETICAL POPULATION BIOLOGY. 104 (2015): 68-77. Abstract

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Lessa, Ivan, Glauco Carneiro, Miguel Monteiro, and Fernando Brito e Abreu. "A Concern Visualization Approach for Improving MATLAB and Octave Program Comprehension." 29th Brazilian Symposium on Software Engineering. Belo Horizonte, Brasil: CPS, 2015. sbes2015camera_ready.pdf
Alves, André, Fernando P. Birra, and João M. Lourenço. "Como separar o trigo do joio? Ou: Como selecionar a melhor fotografia de um conjunto de fotografias semelhantes." Proceedings of INForum Simpósio de Informática. INForum 2015. Covilhã, Portugal 2015. Abstractinforum15-photo.pdf

O advento da fotografia digital está na base de uma clara mudança de paradigma no processo de gestão da fotografia por amadores. Porque tirar mais uma fotografia agora não representa qualquer custo adicional, é frequente tirarem-se múltiplas fotografias ao mesmo sujeito, na expectativa de que uma delas corresponda aos padrões de qualidade desejados, em termos de iluminação, foco e enquadramento. Assumindo que a questão do enquadramento se resolve facilmente recorrendo ao recorte (crop) da fotografia, tem-se ainda assim que selecionar qual das várias fotografias bem enquadradas, tecnicamente parecidas em termos de iluminação e foco, vamos guardar (e por oposição quais vamos descartar). A escolha da melhor fotografia com base na observação visual em ecrã de computador é um processo muito pouco preciso e, portanto, gerador de sensações de insegurança que resultam, muitas vezes, na opção de não descartar nenhuma das várias fotografias semelhantes. Neste artigo propomo-nos endereçar a questão de como ajudar um fotógrafo amador a selecionar a melhor fotografia de um conjunto de fotografias semelhantes em termos técnicos (foco e iluminação) e de enquadramento. Este processo é baseado num workflow suportado por um pacote de software, que com alguma ajuda do utilizador permite ordenar um conjunto de fotografias semelhantes, sendo assim possível escolher aquela que melhor corresponde às expectativas e dando segurança e conforto na eventual eliminação das restantes.

Monteiro, Ricardo, João M. Lourenço, and Hervé Paulino. "Um Armazenamento Distribuído para uma Rede de Dispositivos Móveis." Proceedings of INForum Simpósio de Informática. INForum 2015. Covilhã, Portugal 2015. Abstractinforum2015-rmonteiro.pdf

Os dispositivos móveis em proximidade geográfica representam um conjunto de recursos inexplorados, tanto em termos de capacidade de processamento como de rmazenamento, o que abre caminho para novas aplicações com oportunidades e desafios únicos. Os sistemas atuais de partilha de dados (e. g., fotos, música, vídeos) para dispositivos móveis exigem que exista conectividade com a Internet para funcionarem. No entanto, em ambientes onde a conectividade com a Internet não é constante ou de boa qualidade (e. g., eventos desportivos e concertos), ou em locais remotos onde as infraestruturas de rede não existem, é difícil (ou mesmo impossível) partilhar dados entre vários dispositivos móveis. Para resolver este problema, os dispositivos móveis podem formar uma rede ad hoc para compartilhar os seus dados e recursos. Neste artigo propomos um sistema de armazenamento distribuído para partilha de dados entre dispositivos móveis de uso diário, e. g., smartphones e tablets, usando um mecanismo de melhor esforço para garantir persistência e disponibilidade de dados suportando churn (entrada e saída inesperada de dispositivos).

Picado, Ana, Susana M. Paixao, Liliana Moita, Luis Silva, Mario S. Diniz, Joana Lourenco, Isabel Peres, Luisa Castro, Jose Brito Correia, Joana Pereira, Isabel Ferreira, Antnio Pedro Alves Matos, Pedro Barquinha, and Elsa Mendonca. "A multi-integrated approach on toxicity effects of engineered TiO2 nanoparticles." Frontiers of Environmental Science & Engineering. 9 (2015): 793-803. AbstractWebsite
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Inácio, Micael M. G., André F. O. Almeida, Duarte M. V. Faria, Válter J. G. Lúcio, and António Pinho Ramos. "Punching of high strength concrete flat slabs without shear reinforcement." Engineering Structures. 103 (2015): 275-284. AbstractWebsite

The experimental research carried out to study the punching behavior of high strength concrete (HSC) flat slabs is reported in the present work. Three flat slab specimens were cast using HSC and another one with normal strength concrete (NSC), to be used as a reference slab. The HSC mix presented a compressive strength of about 130MPa, with a basalt coarse aggregate. The tested specimens were square with 1650mm side and 125mm thickness. The longitudinal reinforcement ratio varied between 0.94{%} and 1.48{%}. The experimental results show that the use of HSC led to a significant load capacity increase when compared with the reference model made with NSC. Furthermore, the experimental results also indicated that as the longitudinal reinforcement ratio increased, the punching capacity also increased. The results obtained in this set of experimental tests and others collected from the literature were compared with the code provisions by EC2, MC2010 and ACI 318-11.

Diepold, Marc, Luis M. P. Fernandes, Jorge Machado, Pedro Amaro, Marwan Abdou-Ahmed, Fernando D. Amaro, Aldo Antognini, François Biraben, Tzu-Ling Chen, Daniel S. Covita, Andreas J. Dax, Beatrice Franke, Sandrine Galtier, Andrea L. Gouvea, Johannes Götzfried, Thomas Graf, Theodor W. Hänsch, Malte Hildebrandt, Paul Indelicato, Lucile Julien, Klaus Kirch, Andreas Knecht, Franz Kottmann, Julian J. Krauth, Yi-Wei Liu, Cristina M. B. Monteiro, Françoise Mulhauser, Boris Naar, Tobias Nebel, François Nez, Jose Paulo Santos, Joaquim M. F. dos Santos, Karsten Schuhmann, Csilla I. Szabo, David Taqqu, João F. C. A. Veloso, Andreas Voss, Birgit Weichelt, and Randolf Pohl. "Improved x-ray detection and particle identification with avalanche photodiodes." Review of Scientific Instruments. 86 (2015): 053102-7. AbstractWebsite
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Farchi, Eitan, Robert M. Hierons, and João M. Lourenço. "Special issue on Testing, Analysis and Debugging of Concurrent Programs." Software Testing, Verification and Reliability. 25 (2015): 165-166. AbstractWebsite

This special issue concerns a range of issues related to the development of concurrent programs. This is an important topic, because many systems are now either multi-threaded or distributed, and it is well known that concurrency makes testing, analysis and debugging significantly more complicated. Essentially, the alternative interleavings of events can lead to different behaviours, and so any analysis, debugging or testing technique must consider these interleavings. The interest in this topic is reflected in the larger than normal issue, which contains five papers. The papers fall into three groups: we start with a paper on debugging, then have two on static analysis techniques and finally have two on testing. All papers were reviewed in the normal way.

Diepold, Marc, Luis M. P. Fernandes, Jorge Machado, Pedro Amaro, Marwan Abdou-Ahmed, Fernando D. Amaro, Aldo Antognini, Fran{\c c}ois Biraben, Tzu-Ling Chen, Daniel S. Covita, Andreas J. Dax, Beatrice Franke, Sandrine Galtier, Andrea L. Gouvea, Johannes Götzfried, Thomas Graf, Theodor W. Hänsch, Malte Hildebrandt, Paul Indelicato, Lucile Julien, Klaus Kirch, Andreas Knecht, Franz Kottmann, Julian J. Krauth, Yi-Wei Liu, Cristina M. B. Monteiro, Fran{\c c}oise Mulhauser, Boris Naar, Tobias Nebel, Fran{\c c}ois Nez, José Paulo Santos, Joaquim M. F. dos Santos, Karsten Schuhmann, Csilla I. Szabo, David Taqqu, João F. C. A. Veloso, Andreas Voss, Birgit Weichelt, and Randolf Pohl. "{Improved x-ray detection and particle identification with avalanche photodiodes}." Review of Scientific Instruments. 86 (2015): 053102. AbstractWebsite
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Lessa, Ivan, Glauco Carneiro, Miguel Monteiro, and Fernando Brito e Abreu. "On the Use of a Multiple View Interactive Environment for MATLAB and Octave Program Comprehension." 15th International Conference on Computational Science and Its Applications. Alberta, Canada: Springer, 2015. iccsa_2015_cameraready_final.pdf
Lessa, Ivan, Glauco Carneiro, Miguel Monteiro, and Fernando Brito e Abreu. "Scaffolding MATLAB and Octave Software Comprehension Through Visualization." 27th International Conference on Software Engineering and Knowledge Engineering. Pittburgh, USA: IEEE, 2015. seke_20150619_final_with_doi.pdf
Silva, João A., Hervé Paulino, and João M. Lourenço. "Crowd-Sourcing Mobile Devices to Provide Storage in Edge-Clouds." Proceedings of the Doctoral Symposium of the 16th International Conference on Distributed Computing and Networking. ICDCN 2015. 2015. Abstracticdcn15srf.pdf

Given the proliferation and enhanced capabilities of mobile devices, their computational and storage resources can now be combined in a wireless cloud of nearby mobile devices, a mobile edge-cloud. These clouds are of particular interest in low connectivity scenarios, e.g., sporting events and disaster scenarios. In these dynamic clouds it is necessary to reliably disseminate and share data, and also to offload data processing computations to other devices in the edge-cloud. We are particularly interested in supporting storage services in these new type of edge-clouds, as a mean to enable data sharing, dissemination and querying, as well as to serve as a distributed file system for offloaded computations. In this Ph.D. thesis, we propose to address these questions by researching on the usage of ad-hoc clouds of mobile devices to develop an efficient storage service capable of providing high availability and reliability.