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2015
Mano, F, Aroso I, Barreiros S, Borges JP, Reis R, Duarte AR, Paiva A.  2015.  Production of Poly(vinyl alcohol) (PVA) Fibers with Encapsulated Natural Deep Eutectic Solvent (NADES) Using Electrospinning. ACS Sustainable Chemistry & Engineering. 3(10):2504–2509. AbstractWebsite

Functionalized electrospun fibers are of great interest for biomedical applications such as in the design of drug delivery systems. Nevertheless, in some cases the molecules of interest have poor solubility in water or have high melting temperatures. These drawbacks can be overcome using deep eutectic solvents. In this work, poly(vinyl alcohol) (PVA), a common biodegradable biopolymer, was used to produce new functionalized fibers with the eutectic mixture choline chloride:citric acid in a molar ratio of (1:1) ChCl:CA (1:1), which was used as a model system. Fibers were produced from an aqueous solution with 7.8% (w/v) and 9.8% (w/v) of 95% hydrolyzed PVA and a 2% (v/v) of ChCl:CA (1:1). Smooth, uniform fibers with an average diameter of 0.4 μm were obtained with a content of 19.8 wt % of ChCl:CA (1:1) encapsulated.

Johnston, EM, Dell'Acqua S, Pauleta SR, Moura I, Solomon EI.  2015.  Protonation state of the Cu4S2 CuZ site in nitrous oxide reductase: redox dependence and insight into reactivity. Chem Sci. 6:5670-5679.
Aquino, AS, Bernard FL, Borges JV, Mafra L, Dalla Vecchia F, Vieira MO, Ligabue R, Seferin M, Chaban VV, Cabrita EJ, Einloft S.  2015.  Rationalizing the role of the anion in CO2 capture and conversion using imidazolium-based ionic liquid modified mesoporous silica. RSC Advances. 5:64220-64227., Number {79}, {THOMAS GRAHAM HOUSE, SCIENCE PARK, MILTON RD, CAMBRIDGE CB4 0WF, CAMBS, ENGLAND}: {ROYAL SOC CHEMISTRY} Abstract

Covalently supported ionic liquids in mesoporous materials were prepared by grafting 1-methyl-3-(3-trimethoxysylilpropyl)imidazolium chloride in MCM-41. Subsequently, the {[}Cl-] anion was changed to {[}BF4-], {[}PF6-] or {[}Tf2N-]. These materials that present an advantageous combination of the properties of mesoporous solid materials and ionic liquids were evaluated for CO2 sorption as well as catalysts for CO2 conversion into cyclic carbonate using propylene oxide. The material with the {[}Cl-] anion had the best performance for both CO2 sorption and conversion. A CO2 sorption of 11 w/w% on the adsorbent was achieved and the cycloaddition reaction exhibited a conversion of 67% with 82% selectivity with the catalyst remaining active after 5 cycles, proving that the same sorbent/catalyst setup can be used for both CO2 capture and conversion. Based on the experimental data and electronic-structure numerical simulations, we have hypothesized two major reasons why chloride out performs other anions when adsorbed on MCM-41 unlike unsupported ionic liquids.

Araújo, N.  2015.  A reindustrialização de Portugal num contexto de crise e hegemonia industrial dos países emergentes. IET Working Papers Series. 2015(3):20. AbstractWebsite

This working paper aimed to understand the importance and the role of Industry for the Portuguese' economic recovery, integrated in a context of progressive deindustrialisation over the last few years, and simultaneously an impressive growth and domain over some production sectors by emergent countries, associated with the 2008 crisis. We intended to analyse this problematic in both national and European levels, bringing into context the national industry, identifying the causes for the progressive abandon of the industry and its consequences. To identify the main stakeholders and their role on the reindustrialization process. To identify policies and instruments contributing to the promotion of this reindustrialisation and main conclusions.

Moniz, AB, Decker M.  2015.  Robotics Technology Assessment: New Challenges, Implications and Risks. The Next Horizon of Technology Assessment. :249-252., Prague: Technology Centre ASCR
Moniz, AB, Decker M.  2015.  Robotics Technology Assessment: New challenges, implications and risks. A session summary. The Next Horizon of Technology Assessment. :249-252., Prague: Technology Centre ASCR
Maia, MJ, Krings B-J.  2015.  Robots in surgery: Transformation of work in the operation room. Practices of innovation and responsibility: Insights from methods, governance and action. :111-128., Berlin: AKA
Silveira, CM, Quintas PO, Moura I, Moura JJG, Hildebrandt P, Almeida MG, Todorovic S.  2015.  SERR spectroelectrochemical study of cytochrome cd1 nitrite reductase co-immobilized with physiological redox partner cytochrome c552 on biocompatible metal electrodes. Plos One. 10:e0129940.
Contreras, J, Tornero J, Ferreira I, Martins R, Gomes L, Fortunato E.  2015.  Simulated and Real Sheet-of-Light 3D Object Scanning Using a-Si:H Thin Film PSD Arrays. Sensors. 15(12):29938-29949. Abstract

A MATLAB/SIMULINK software simulation model (structure and component blocks) has been constructed in order to view and analyze the potential of the PSD (Position Sensitive Detector) array concept technology before it is further expanded or developed. This simulation allows changing most of its parameters, such as the number of elements in the PSD array, the direction of vision, the viewing/scanning angle, the object rotation, translation, sample/scan/simulation time, etc. In addition, results show for the first time the possibility of scanning an object in 3D when using an a-Si:H thin film 128 PSD array sensor and hardware/software system. Moreover, this sensor technology is able to perform these scans and render 3D objects at high speeds and high resolutions when using a sheet-of-light laser within a triangulation platform. As shown by the simulation, a substantial enhancement in 3D object profile image quality and realism can be achieved by increasing the number of elements of the PSD array sensor as well as by achieving an optimal position response from the sensor since clearly the definition of the 3D object profile depends on the correct and accurate position response of each detector as well as on the size of the PSD array.

Ferreira, M, Loureiro J, Nogueira A, Rodrigues A, Martins R, Ferreira I.  2015.  SnO2 thin Film Oxides Produced by rf Sputtering for Transparent Thermoelectric Devices. Mater. Today-Proc. 2(2):647-653. AbstractWebsite

The combination of high transparency and good thermoelectric properties of SnO2 can open new field of applications for the thin film thermoelectric materials. Here we report on SnO2 thin films with transmittance above 90%, resistivity bellow 10-3 Ωm and a Power Factor around 10-4 W/m.K2, for a Seebeck of -255 μV/K, at room temperature. The effect of film thickness and post-deposition annealing on the thermoelectric properties were analysed. The performances of a single layer thermoelectric device are also presented.

Neagu, E, Lança MC, Dias C, Marat-Mendes J.  2015.  Space charge and dipolar charge contribution at polar polymers polarization. IEEE Transactions on Dielectrics and Electrical Insulation. 22(3):1419-1426. AbstractWebsite

The thermally stimulated discharge current, the final thermally stimulated discharge current, DC conductivity and the final thermally stimulated discharge current with partially blocking electrode measures were used to analyze electrical behavior of Nylon 11. The objective was to discriminate between dipole related effects and space charge related effects. The space charge effects are dominant in the temperature range from room temperature to 170 °C. By using a Teflon-FEP partially blocking electrode, the space charge injected in the sample is diminished and the effects related to dipole movement can be observed. Beside the two known relaxations for Nylon 11, one associated with the glass transition around 60 °C and a second one associated with a molecular motion in the rigid-amorphous phase at 96 °C, a weak relaxation was observed around 168 °C. The peak around 96 °C is quite broad been composed of two narrow peaks. The final thermally stimulated discharge current method allows a better selection of the experimental conditions for sample charging (polarization) to have only a partial overlap between the nearby peaks. The peak's maximum current and temperature are dependent on the ratio between the charging and discharging time and temperature given a possibility to discriminate between dipolar and space charge effects. A pyroelectric current changes sign around 140 °C indicating that the amidegroup dipoles are frozen in opposite directions when the sample temperature is below 140 °C (amorphous and rigid-amorphous phase) or above (crystalline phase). The conductivity is controlled by the competition between n(E,T) and μ(E,T) indicating a space charge controlled conductivity mechanism.

Reed, P, Atilano ML, Alves R, Hoiczyk E, Sher X, Reichmann NT, Pereira PM, Roemer T, Filipe SR, Pereira-Leal JB, Ligoxygakis P, Pinho MG.  2015.  Staphylococcus aureus survives with a minimal peptidoglycan synthesis machinery but sacrifices virulence and antibiotic resistance. PLoS Pathogens. 11:e1004891.
Coelho, C, Foti A, Tobias H, Santos-Silva T, Leimkühler S, Romão MJ.  2015.  Structural insights into xenobiotic and inhibitor binding to human aldehyde oxidase. Nature Chemical Biology. 11(10)
Dantas, JM, Campelo LM, Duke NEC, Salgueiro CA, Pokkuluri PR.  2015.  The structure of PccH from Geobacter sulfurreducens: a novel low reduction potential monoheme cytochrome essential for accepting electrons from an electrode. FEBS J. 282(11):2215-2231. AbstractWebsite

The structure of cytochrome c (GSU3274) designated as PccH from Geobacter sulfurreducens was determined at a resolution of 2.0 Å. PccH is a small (15 kDa) cytochrome containing one c-type heme, found to be essential for the growth of G. sulfurreducens with respect to accepting electrons from graphite electrodes poised at -300 mV versus standard hydrogen electrode. with fumarate as the terminal electron acceptor. The structure of PccH is unique among the monoheme cytochromes described to date. The structural fold of PccH can be described as forming two lobes with the heme sandwiched in a cleft between the two lobes. In addition, PccH has a low reduction potential of -24 mV at pH 7, which is unusual for monoheme cytochromes. Based on difference in structure, together with sequence phylogenetic analysis, we propose that PccH can be regarded as a first characterized example of a new subclass of class I monoheme cytochromes. The low reduction potential of PccH may enable the protein to be redox active at the typically negative potential ranges encountered by G. sulfurreducens. Because PccH is predicted to be located in the periplasm of this bacterium, it could not be involved in the first step of accepting electrons from the electrode but is very likely involved in the downstream electron transport events in the periplasm.

Silva, JA, Vale TM, Dias RJ, Paulino H, Lourenço JM.  2015.  Supporting Multiple Data Replication Models in Distributed Transactional Memory. Proceedings of the 2015 International Conference on Distributed Computing and Networking. , Goa, India: ACM Abstract2015-icdcn.pdf

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Carvalho, LCR, Ribeiro D, Seixas RSGR, Silva AMS, Nave M, Martins AC, Erhardt S, Fernandes E, Cabrita EJ, Marques MMB.  2015.  Synthesis and evaluation of new benzimidazole-based COX inhibitors: a naproxen-like interaction detected by STD-NMR. RSC Advances. 5:49098-49109., Number {61} Abstract

Non-steroidal anti-inflammatory drugs exert their pharmacological activity through inhibition of cyclooxygenase 1 and 2 (COX-1 and COX-2). Recent research suggests that a balanced inhibition of both COX-1 and COX-2 is the key to reduce the side-effects exhibited by COX inhibitors. We developed new benzimidazole-based compounds that showed a balanced COX inhibition, supported by molecular docking screening. The human whole blood assays demonstrated that the ester derivatives were potent inhibitors. Competitive saturation transfer difference (STD)-NMR experiments, in the presence of COX-2, using naproxen and diclofenac demonstrated that ester derivatives do not compete with diclofenac for the same binding site, but compete with the allosteric inhibitor naproxen. Combination of NMR spectroscopy with molecular docking has permitted us to detect a new naproxen-like inhibitor, which could be used for future drug development.

Simoes, S, Huppes G, Seixas J.  2015.  A Tangled Web: Assessing overlaps between energy and environmental policy instruments along the electricity supply chain. Environmental Policy and Governance.
Krings, B-J, Hülsken-Giesler M.  2015.  Technik und Pflege in einer Gesellschaft des langen Lebens - Einführung in den Schwerpunkt. Technikfolgenabschätzung - Theorie und Praxis. 24(2):4-11.
Soares, PIP, Lochte F, Echeverria C, Pereira L, Coutinho J, Ferreira I, Novo C, Borges JP.  2015.  Thermal and magnetic properties of iron oxide colloids: influence of surfactants. Nanotechnology. 26(42):425704. AbstractWebsite

Iron oxide nanoparticles (NPs) have been extensively studied in the last few decades for several biomedical applications such as magnetic resonance imaging, magnetic drug delivery and hyperthermia. Hyperthermia is a technique used for cancer treatment which consists in inducing a temperature of about 41–45 °C in cancerous cells through magnetic NPs and an external magnetic field. Chemical precipitation was used to produce iron oxide NPs 9 nm in size coated with oleic acid and trisodium citrate. The influence of both stabilizers on the heating ability and in vitro cytotoxicity of the produced iron oxide NPs was assessed. Physicochemical characterization of the samples confirmed that the used surfactants do not change the particles' average size and that the presence of the surfactants has a strong effect on both the magnetic properties and the heating ability. The heating ability of Fe3O4 NPs shows a proportional increase with the increase of iron concentration, although when coated with trisodium citrate or oleic acid the heating ability decreases. Cytotoxicity assays demonstrated that both pristine and trisodium citrate Fe3O4 samples do not reduce cell viability. However, oleic acid Fe3O4 strongly reduces cell viability, more drastically in the SaOs-2 cell line. The produced iron oxide NPs are suitable for cancer hyperthermia treatment and the use of a surfactant brings great advantages concerning the dispersion of NPs, also allowing better control of the hyperthermia temperature.

Soares, PIP, Lochte F, Echeverria C, Pereira LCJ, Coutinho JT, Ferreira IMM, Novo CMM, Borges JPMR.  2015.  Thermal and magnetic properties of iron oxide colloids: influence of surfactants. Nanotechnology. 26(42):425704. AbstractWebsite

Iron oxide nanoparticles (NPs) have been extensively studied in the last few decades for several biomedical applications such as magnetic resonance imaging, magnetic drug delivery and hyperthermia. Hyperthermia is a technique used for cancer treatment which consists in inducing a temperature of about 41–45 °C in cancerous cells through magnetic NPs and an external magnetic field. Chemical precipitation was used to produce iron oxide NPs 9 nm in size coated with oleic acid and trisodium citrate. The influence of both stabilizers on the heating ability and in vitro cytotoxicity of the produced iron oxide NPs was assessed. Physicochemical characterization of the samples confirmed that the used surfactants do not change the particles' average size and that the presence of the surfactants has a strong effect on both the magnetic properties and the heating ability. The heating ability of Fe3O4 NPs shows a proportional increase with the increase of iron concentration, although when coated with trisodium citrate or oleic acid the heating ability decreases. Cytotoxicity assays demonstrated that both pristine and trisodium citrate Fe3O4 samples do not reduce cell viability. However, oleic acid Fe3O4 strongly reduces cell viability, more drastically in the SaOs-2 cell line. The produced iron oxide NPs are suitable for cancer hyperthermia treatment and the use of a surfactant brings great advantages concerning the dispersion of NPs, also allowing better control of the hyperthermia temperature.

Gonçalves, L, Santos Z, Amado MP, Craveiro I, Cabral J, Lapão L, Alves D, Simões R.  2015.  Urban Planning and Health Inequities: looking in a small-scale in a City of Cape Verde. PlosOne Journal. (DOI: 10.1371/journal.pone.0142955): DOI: 10.1371/journal.pone.0142955
Boavida, N.  2015.  The use and influence of indicators in decisions about technology innovation: Quantitative results from questionnaires in Portugal. Scientific Knowledge and the Transgression of Boundaries. (Krings, Bettina, et al, Eds.)., Berlin: Springer
Palma, SI, Rodrigues CA, Carvalho A, Morales PM, Freitas F, Fernandes AR, Cabral JS, Roque ACA.  2015.  A value-added exopolysaccharide as a coating agent for MRI nanoprobes. Nanoscale. (7):14272-14283. AbstractWebsite

Fucopol, a fucose-containing exopolysaccharide (EPS) produced by the bacterium Enterobacter A47 DSM 23139 using glycerol as a carbon source, was employed as a new coating material for iron oxide magnetic nanoparticles (MNP). The coated particles were assessed as nanoprobes for cell labeling by Magnetic Resonance Imaging (MRI). The MNP were synthesized by a thermal decomposition method and transferred to aqueous medium by ligand-exchange reaction with meso-2,3-dimercaptosuccinic acid (DMSA). Covalent binding of EPS to DMSA-stabilized nanoparticles (MNP-DMSA) resulted in a hybrid magnetic-biopolymeric nanosystem (MNP-DMSA-EPS) with a hydrodynamic size of 170 nm, negative surface charge at physiological conditions and transverse to longitudinal relaxivities ratio, r2/r1, of 148. In vitro studies with two human cell lines (colorectal carcinoma - HCT116 - and neural stem/progenitor cells - ReNcell VM) showed that EPS promotes internalization of nanoparticles in both cell lines. In vitro MRI cell phantoms also showed superior performance of MNP-DMSA-EPS in ReNcell VM, for which iron dose-dependent MRI signal drop was obtained at relatively low iron concentrations (12 - 20 µg Fe/ml) and short incubation time. Furthermore, ReNcell VM multipotency was not affected by culture in the presence of MNP-DMSA or MNP-DMSA-EPS for 14 days. Our study suggests that Fucopol-coated MNP represent useful cell labeling nanoprobes for MRI.