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2016
Silva, Teresa, Francisco Costa, Judite Fernandes, Rogério Calvo, and Octávio Mateus The use of a portable X-ray fluorescence analyzer in the reconstitution of dinosaur fossils. European Conference on X-Ray Spectrometry. June 19 – 24, 2016, Gothenburg, Sweden, 2016. Abstract
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Silva, Teresa, Francisco Costa, Judite Fernandes, Rog\é\}rio Calvo, and Oct\á\}vio Mateus. "The use of a portable X-ray fluorescence analyzer in the reconstitution of dinosaur fossils." European Conference on X-Ray Spectrometry. June 19 \–\} 24, 2016, Gothenburg, Sweden 2016. 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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Moreira, Ana, Gunter Mussbacher, João Araújo, and Pablo Sánchez. "Welcome to the Sixth International Workshop on Model-Driven Requirements Engineering (MoDRE)." 24th {IEEE} International Requirements Engineering Conference, {RE} 2016, Beijing, China, September 12-16, 2016. 2016. 122. Abstract
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Santos, Mafalda, Catarina Gralha, Miguel Goulão, João Araújo, Ana Moreira, and Joao Cambeiro. "What is the Impact of Bad Layout in the Understandability of Social Goal Models?" 24th {IEEE} International Requirements Engineering Conference, {RE} 2016, Beijing, China, September 12-16, 2016. 2016. 206-215. Abstract
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Aroso, Ivo M., João C. Silva, Francisca Mano, Ana S. D. Ferreira, Madalena Dionísio, Isabel Sá-Nogueira, Susana Barreiros, Rui L. Reis, Alexandre Paiva, and Ana Rita C. Duarte. "{Dissolution enhancement of active pharmaceutical ingredients by therapeutic deep eutectic systems}." European Journal of Pharmaceutics and Biopharmaceutics. 98 (2016): 57-66. AbstractWebsite

A therapeutic deep eutectic system (THEDES) is here defined as a deep eutectic solvent (DES) having an active pharmaceutical ingredient (API) as one of the components. In this work, THEDESs are proposed as enhanced transporters and delivery vehicles for bioactive molecules. THEDESs based on choline chloride (ChCl) or menthol conjugated with three different APIs, namely acetylsalicylic acid (AA), benzoic acid (BA) and phenylacetic acid (PA), were synthesized and characterized for thermal behaviour, structural features, dissolution rate and antibacterial activity. Differential scanning calorimetry and polarized optical microscopy showed that ChCl:PA (1:1), ChCl:AA (1:1), menthol:AA (3:1), menthol:BA (3:1), menthol:PA (2:1) and menthol:PA (3:1) were liquid at room temperature. Dissolution studies in PBS led to increased dissolution rates for the APIs when in the form of THEDES, compared to the API alone. The increase in dissolution rate was particularly noticeable for menthol-based THEDES. Antibacterial activity was assessed using both Gram-positive and Gram-negative model organisms. The results show that all the THEDESs retain the antibacterial activity of the API. Overall, our results highlight the great potential of THEDES as dissolution enhancers in the development of novel and more effective drug delivery systems.

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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Silva, João C., Alexandre A. Barros, Ivo M. Aroso, Dario Fassini, Tiago H. Silva, Rui L. Reis, and Ana Rita C. Duarte. "{Extraction of Collagen/Gelatin from the Marine Demosponge Chondrosia reniformis (Nardo, 1847) Using Water Acidified with Carbon Dioxide - Process Optimization}." Industrial and Engineering Chemistry Research. 55 (2016): 6922-6930. Abstract

Marine sponges are a rich source of natural bioactive compounds. One of the most abundant valuable products is collagen/gelatin, which presents an interesting alternative source for pharmaceutical and biomedical applications. We have previously proposed an innovative green technology for the extraction of collagen/gelatin from marine sponges based in water acidified with carbon dioxide. In this work, we have optimized the process operating conditions toward high yields and collagen quality as well as to reduce extraction procedure duration and energy consumption. The process extraction efficiency is higher than 50{%}, corresponding to a yield of approximately 10{%} of the sponge dry mass, obtained for mild operating conditions of 10 bar and 3 h. The extracted material was characterized by scanning electron microscopy (SEM), rheology, Fourier transformed infrared spectroscopy (FTIR), circular dichroism (CD), amino acid analysis, and SDS-PAGE. The extracts were found to be composed of highly pure mixtures of co...

Duarte, Ana Rita C., Devid Maniglio, Nuno Sousa, João F. Mano, Rui L. Reis, and Claudio Migliaresi. "{From honeycomb- to microsphere-patterned surfaces of poly(lactic acid) and a starch-poly(lactic acid) blend via the breath figure method.}." Journal of applied biomaterials {&} functional materials. 15 (2016). AbstractWebsite

BACKGROUND This study investigated the preparation of ordered patterned surfaces and/or microspheres from a natural-based polymer, using the breath figure and reverse breath figure methods. METHODS Poly(D,L-lactic acid) and starch poly(lactic acid) solutions were precipitated in different conditions - namely, polymer concentration, vapor atmosphere temperature and substrate - to evaluate the effect of these conditions on the morphology of the precipitates obtained. RESULTS The possibility of fine-tuning the properties of the final patterns simply by changing the vapor atmosphere was also demonstrated here using a range of compositions of the vapor phase. Porous films or discrete particles are formed when the differences in surface tension determine the ability of polymer solution to surround water droplets or methanol to surround polymer droplets, respectively. In vitro cytotoxicity was assessed applying a simple standard protocol to evaluate the possibility to use these materials in biomedical applications. Moreover, fluorescent microscopy images showed a good interaction of cells with the material, which were able to adhere on the patterned surfaces after 24 hours in culture. CONCLUSIONS The development of patterned surfaces using the breath figure method was tested in this work for the preparation of both poly(lactic acid) and a blend containing starch and poly(lactic acid). The potential of these films to be used in the biomedical area was confirmed by a preliminary cytotoxicity test and by morphological observation of cell adhesion.

Barros, A., S. Quraishi, M. Martins, P. Gurikov, R. Subrahmanyam, I. Smirnova, A. R. C. Duarte, and R. L. Reis. "{Hybrid Alginate-Based Cryogels for Life Science Applications}." Chemie-Ingenieur-Technik. 88 (2016). Abstract

© 2016 WILEY-VCH Verlag GmbH {&} Co. KGaA, Weinheim. This work presents a novel route toward porous scaffolds for tissue engineering and regenerative medicine (TERM) applications. Hybrid cryogels with gelatin, gellan gum, carboxymethylcellulose, and lignin were prepared by a two-step process. Textural properties of the cryogels were analyzed by SEM and micro-computed tomography. The results indicated that rapid freezing retained sample shape and yielded macroporous materials. The mechanical properties of the cryogels were characterized in compression mode. Cytotoxicity studies indicated that the hybrid-alginate cryogels did not present cytotoxicity and have the potential to be used in TERM.

Barros, A. A., I. M. Aroso, T. H. Silva, J. F. Mano, A. R. C. Duarte, and R. L. Reis. "{In vitro bioactivity studies of ceramic structures isolated from marine sponges}." Biomedical Materials (Bristol). 11 (2016). Abstract

© 2016 IOP Publishing Ltd. In this work, we focused on the potential of bioceramics from different marine sponges - namely Petrosia ficiformis, Agelas oroides and Chondrosia reniformis - for novel biomedical/industrial applications. The bioceramics from these sponges were obtained after calcination at 750 °C for 6 h in a furnace. The morphological characteristics were evaluated by scanning electron microscopy (SEM). The in vitro bioactivity of the bioceramics was evaluated in simulated body fluid (SBF) after 14 and 21 d. Observation of the bioceramics by SEM after immersion in SBF solution, coupled with spectroscopic elemental analysis (EDS), showed that the surface morphology was consistent with a calcium-phosphate (Ca/P) coating, similar to hydroxyapatite crystals (HA). Evaluation of the characteristic peaks of Ca/P crystals by Fourier transform infrared spectroscopy and x-ray diffraction further confirmed the existence of HA. Cytotoxicity studies were carried out with the different ceramics and these were compared with a commercially available Bioglass ® . In vitro tests demonstrated that marine bioceramics from these sponges are non-cytotoxic and have the potential to be used as substitutes for synthetic Bioglass ® .

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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Bedon, Chiara, Filipe Santos, Claudio Amadio, and Corneliu Cismasiu. "Passive and active control systems for adaptive glazing systems and envelopes." European COST Action TU1403 "Adaptive facades network" Industry Workshop. Delft, The Netherlands 2015.
Cardoso, Tiago, Vitor Santos, Carolina Santos, and José Barata. "Games’ Social Tech Booster." SGames 2015 - 5th International Conference on Serious Games, Interaction and Simulation. 2015. Abstract

The society has organized itself towards facing existing social needs like the care for children with Down syndrome, Deafness or Autism Spectrum Disorders, among several other pathologies. As a result, several organizations emerged towards handling these issues, composed of doctors, therapists, psychologists, among other professionals, but excluding technology experts. On the other hand side, the finalist students from technology universities usually have a final course where they have to create a complete project from scratch. This article proposes a method for applying the effort and enthusiasm of such students in the above mentioned social causes through games’ development.

Kchaou, Omaya Bellaaj, Amin Sallem, Pedro Pereira, Mourad Fakhfakh, and Maria Helena Fino. "Multi-objective sensitivity-based optimization of analog circuits exploiting NSGA-II front ranking." Synthesis, Modeling, Analysis and Simulation Methods and Applications to Circuit Design (SMACD), 2015 International Conference on. Istanbul, Turkey 2015. 1-4. Abstract

This work deals with the multi-objective optimization of analog circuits by generating the Pareto front where elements are low sensitive to parameters' variations. NSGA-II is used for obtaining the non-dominated solutions. Richardson extrapolation technique is used for the in-loop optimization approach for computing partial derivatives and, thus, the solutions' sensitivity. NSGA-II Pareto fronts' intrinsic ranking is exploited for the generation of the new ‘low-sensitive’ Pareto front. The case of the optimal sizing of a CMOS voltage follower is considered to exemplify the proposed approach.

Santos, J. P., J. P. Marques, M. C. Martins, P. Indelicato, E. P. Benis, T. J. M. Zouros, and F. Parente. "Energy levels, transition rates and lifetimes for Li-like ions with Z≤ 10 in the 1 s2 s( 3S)3ℓ states." Journal of Physics: Conference Series. 635 (2015): 052060-2. AbstractWebsite
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Marques, J. P., M. Guerra, F. Parente, J. P. Santos, P. Indelicato, and J. M. Sampaio. "K-shell width, fluorescence yield, and Kβ/ Kαintensity ratio calculation for Fe in the Dirac-Fock approach." Journal of Physics: Conference Series. 635 (2015): 092094-2. AbstractWebsite
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Sampaio, J. M., M. Guerra, T. I. Madeira, F. Parente, P. Indelicato, J. P. Santos, and J. P. Marques. "Relativistic calculations of atomic parameters in Ununoctium." Journal of Physics: Conference Series. 635 (2015): 092095-2. AbstractWebsite
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