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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.

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.

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...

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 ® .

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.

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
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.

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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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.

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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Cardoso, Tiago, Vitor Santos, Carolina Santos, and José Barata. "Transferência de Tecnologia para Causas Sociais através dos Vídeo Jogos." VideoJogos 2015. Coimbra-Portugal 2015. Abstract

A sociedade organizou-se para fazer frente a necessidades como o tratamento e acompanhamento de crianças ou jovens com Síndrome de Down, Surdez, Autismo, entre outras patologias. Como resultado, surgiram distintas organizações com o objetivo de lidar com estes casos, compostas por médicos, terapeutas, psicólogos, sociólogos e outros profissionais, mas excluindo profissionais dedicados ao desenvolvimento de novas tecnologias. Por outro lado, alunos finalistas de cursos tecnológicos desenvolvem normalmente um projeto tecnológico do início na disciplina final dos seus cursos - Projeto/Dissertação de fim de curso. Este artigo propõe um método para aplicar o esforço e entusiasmo de tais alunos às causas sociais mencionadas através do desenvolvimento de Jogos.

Barquinha, Pedro, Sonia Pereira, Luis Pereira, Pawel Wojcik, Paul Grey, Rodrigo Martins, and Elvira Fortunato. "Flexible and Transparent WO3 Transistor with Electrical and Optical Modulation." Advanced Electronic Materials. 1 (2015). AbstractWebsite
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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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Barquinha, Pedro, Sónia Pereira, LuÍs Pereira, Pawel Wojcik, Paul Grey, Rodrigo Martins, and Elvira Fortunato. "{Flexible and Transparent WO 3 Transistor with Electrical and Optical Modulation}." Advanced Electronic Materials. 1 (2015): n/a–n/a. AbstractWebsite
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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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Bahubalindruni, Pydi Ganga, Vitor Grade Tavares, Pedro Barquinha, Candido Duarte, Nuno Cardoso, Pedro Guedes de Oliveira, Rodrigo Martins, and Elvira Fortunato. "a-GIZO TFT neural modeling, circuit simulation and validation." Solid-State Electronics. 105 (2015): 30-36. AbstractWebsite
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Kiazadeh, Asal, Daniela Salgueiro, Rita Branquinho, Joana Pinto, Henrique L. Gomes, Pedro Barquinha, Rodrigo Martins, and Elvira Fortunato. "Operational stability of solution based zinc tin oxide/SiO2 thin film transistors under gate bias stress." Apl Materials. 3 (2015). AbstractWebsite
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Kiazadeh, Asal, Daniela Salgueiro, Rita Branquinho, Joana Pinto, Henrique L. Gomes, Pedro Barquinha, Rodrigo Martins, and Elvira Fortunato. "{Operational stability of solution based zinc tin oxide/SiO2 thin film transistors under gate bias stress}." APL Materials. 3 (2015): 062804. AbstractWebsite

In this study, we report solution-processed amorphous zinc tin oxide transistors exhibiting high operational stability under positive gate bias stress, translated by a recoverable threshold voltage shift of about 20{%} of total applied stress voltage. Under vacuum condition, the threshold voltage shift saturates showing that the gate-bias stress is limited by trap exhaustion or balance between trap filling and emptying mechanism. In ambient atmosphere, the threshold voltage shift no longer saturates, stability is degraded and the recovering process is impeded. We suggest that the trapping time during the stress and detrapping time in recovering are affected by oxygen adsorption/desorption processes. The time constants extracted from stretched exponential fitting curves are ≈106 s and 105 s in vacuum and air, respectively.

Ullaha, Sana, Fabio {De Matteis}, Rita Branquinho, Elvira Fortunato, Rodrigo Martins, and Ivan Davoli. "{A combination of solution synthesis {&} solution combustion synthesis for highly conducting and transparent Aluminum Zinc Oxide thin films}." 2015 IEEE 15th International Conference on Nanotechnology (IEEE-NANO). IEEE, 2015. 144-147. Abstract

Aluminum Zinc Oxide has been extensively investigated as a cheap alternative to transparent conducting tin oxide films for electronic and optoelectronic applications. Thin films of Aluminum Zinc Oxide have been developed successfully through a combination of solution combustion synthesis and solution synthesis. Zn(NO3)3·6H2O as metal source was dissolved in 2-methoxyethanol as solvent through combustion synthesis with Urea as fuel while dopant source of AlCl3·6H2O was mixed separately in solvent to avoid aluminum oxide formation in the films. Precursor solutions were obtained mixing Zn {&} Al separate solutions in 9:1, 8:2, and 7:3 ratios respectively with oxide, fuel and dopant concentrations of 0.5, 0.25, 0.1, and 0.05 M. The film stacks have been prepared through spin-coating with heating at 400°C for 10 minutes after each deposition to remove residuals and evaporate solvents. Thermal annealing in oven at 600°C for 1 hour followed by rapid thermal annealing at 500°C {&} 600°C first in vacuum and then in N2-5{%}H2 environment respectively for 10 minutes each reduced the resistivity of film stacks. Film stack with 10 layers for an average thickness of 0.5$μ$m gave the best Hall Effect resistivity of 3.2 × 10-2 $Ømega$-cm in the case of 0.5M solution with Zn:Al mixing ratio of 9:1 for RTA annealings at 600°C with an average total transparency of 80 {%} in the wavelength range of 400-1200 nm. The results show a clear trend that increasing the amount of ingredients resistivity could further be decreased.

Saponaro, A., C. Donadoni, S. R. Pauleta, F. Cantini, M. Matzapetakis, G. Thiel, L. Banci, B. Santoro, and A. Moroni. "HCN Channels: The Molecular Basis for their cAMP-TRIP8b Regulation." Biophysical Journal. Vol. 108. Biophys J, 108. 2015. 366a. Abstract
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