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2016
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.

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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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.

Araujo, Andreia, Manuel J. Mendes, Tiago Mateus, Antonio Vicente, Daniela Nunes, Tomas Calmeiro, Elvira Fortunato, Hugo Aguas, and Rodrigo Martins. "{Influence of the Substrate on the Morphology of Self-Assembled Silver Nanoparticles by Rapid Thermal Annealing}." Journal of Physical Chemistry C (2016). AbstractWebsite
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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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Nunes, D., A. Pimentel, JV Pinto, T. R. Calmeiro, S. Nandy, P. Barquinha, L. Pereira, P. A. Carvalho, E. Fortunato, and R. Martins. "{Photocatalytic behavior of TiO2 films synthesized by microwave irradiation}." Catalysis Today. 278 (2016). Abstract

© 2015 Elsevier B.V. Titanium dioxide was synthesized on glass substrates from titanium (IV)isopropoxide and hydrochloride acid aqueous solutions through microwave irradiation using as seed layer either fluorine-doped crystalline tin oxide (SnO2:F) or amorphous tin oxide (a-SnOx). Three routes have been followed with distinct outcome: (i) equimolar hydrochloride acid/water proportions (1HCl:1water) resulted in nanorod arrays for both seed layers; (ii) higher water proportion (1HCl:3water) originated denser films with growth yield dependent on the seed layer employed; while (iii) higher acid proportion (3HCl:1water) hindered the formation of TiO2. X-ray diffraction (XRD) showed that the materials crystallized with the rutile structure, possibly with minute fractions of brookite and/or anatase. XRD peak inversions observed for the materials synthesized on crystalline seeds pointed to preferred crystallographic orientation. Electron diffraction showed that the especially strong XRD peak inversions observed for TiO2 grown from the 1HCl:3water solution on SnO2:F originated from a [001] fiber texture. Transmittance spectrophotometry showed that the materials with finer structure exhibited significantly higher optical band gaps. Photocatalytic activity was assessed from methylene blue degradation, with the 1HCl:3water SnO2:F material showing remarkable degradability performance, attributed to a higher exposure of (001) facets, together with stability and reusability.

2015
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
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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Rahangdale, H. V., D. Mitra, M. Guerra, J. P. Santos, and S. Saha. "Subshell resolved inner shell ionization cross-sections of High Z elements by electron impact." Journal of Physics: Conference Series. 635 (2015): 052001-2. AbstractWebsite
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Mihaylov, Kaloyan, Stanimir Valtchev, and Rumen Arnaudov. "Smart microgrid sensorless load monitoring and management in {TN}-S and {TN}-C-S electrical networks." 2015 International Conference on Electrical Drives and Power Electronics ({EDPE}). Institute of Electrical {&} Electronics Engineers ({IEEE}), 2015. Abstract
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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).

Johnston, E. M., S. Dell'acqua, S. R. Pauleta, I. Moura, and E. I. Solomon. "Protonation state of the Cu4S2 CuZ site in nitrous oxide reductase: redox dependence and insight into reactivity." Chem Sci. 6 (2015): 5670-5679. AbstractWebsite

Spectroscopic and computational methods have been used to determine the protonation state of the edge sulfur ligand in the Cu4S2 CuZ form of the active site of nitrous oxide reductase (N2OR) in its 3CuICuII (1-hole) and 2CuI2CuII (2-hole) redox states. The EPR, absorption, and MCD spectra of 1-hole CuZ indicate that the unpaired spin in this site is evenly delocalized over CuI, CuII, and CuIV. 1-hole CuZ is shown to have a mu2-thiolate edge ligand from the observation of S-H bending modes in the resonance Raman spectrum at 450 and 492 cm-1 that have significant deuterium isotope shifts (-137 cm-1) and are not perturbed up to pH 10. 2-hole CuZ is characterized with absorption and resonance Raman spectroscopies as having two Cu-S stretching vibrations that profile differently. DFT models of the 1-hole and 2-hole CuZ sites are correlated to these spectroscopic features to determine that 2-hole CuZ has a mu2-sulfide edge ligand at neutral pH. The slow two electron (+1 proton) reduction of N2O by 1-hole CuZ is discussed and the possibility of a reaction between 2-hole CuZ and O2 is considered.

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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Mihaylov, Kaloyan, Stanimir Valtchev, and Rumen Arnaudov. "Sensorless load monitoring and management in electric power grid through energy harvesting." 2015 International Conference on Renewable Energy Research and Applications ({ICRERA}). Institute of Electrical {&} Electronics Engineers ({IEEE}), 2015. Abstract
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Sampaio, J. M., T. I. Madeira, M. Guerra, F. Parente, J. P. Santos, P. Indelicato, and J. P. Marques. "Dirac-Fock calculations of K−, L−, and M-shell fluorescence and Coster-Kronig yields for Ne, Ar, Kr, Xe, Rn, and Uuo." Physical Review A. 91 (2015): 052507. AbstractWebsite
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Guerra, M., Th Stöhlker, P. Amaro, J. Machado, and J. P. Santos. "Electron impact ionization cross-sections for few-electron uranium ions." Journal of Physics B: Atomic, Molecular and Optical Physics. 48 (2015): 1-5. AbstractWebsite

Journal of Physics B: Atomic, Molecular and Optical Physics, 48(2015) 144027. doi:10.1088/0953-4075/48/14/144027

Cardoso, T., P. Pereira, V. Fernaao Pires, and J. F. Martins. "Android-based m-learning remote system for mobile power quality assessment in large buildings with renewable energies." Power Engineering, Energy and Electrical Drives (POWERENG), 2015 IEEE 5th International Conference on. Riga, Latvia 2015. 431-434. Abstract

Power Quality is a generic term focusing on several issues, going from reliability to the quality of service provided by the energy supplier. It addresses limiting aspects such as harmonic distortion, flicker, sags, swells and transients... It is important for the students to understand the differences between the large amounts of events that fit into poor power quality category. Moreover it is important for them to analyze real time non-laboratory events. To provide this experience to the students this paper presents a remote m-learning experimental system where several types of poor power quality events can be tested. The developed system is based on a power quality analysis distributed network and can be remotely accessed from a remote computer or smart phones.