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2012
Vinagre, C., D. Madeira, L. Narciso, H. N. Cabral, and M. Diniz. "Effect of temperature on oxidative stress in fish: Lipid peroxidation and catalase activity in the muscle of juvenile seabass, Dicentrarchus labrax." Ecological Indicators. 23 (2012): 274-279. AbstractWebsite
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Pinheiro, B. A., J. L. A. Bras, S. Najmudin, AL Carvalho, LMA Ferreira, JAM Prates, and CMGA Fontes. "Flexibility and specificity of the cohesin-dockerin interaction: implications for cellulosome assembly and functionality." Biocatalysis and Biotransformation. 30 (2012): 309-315. AbstractWebsite

Cellulosomes are highly elaborate multi-enzyme complexes of Carbohydrate Active enZYmes (CAZYmes) secreted by cellulolytic microorganisms, which very effectively degrade the most abundant polymers on Earth, cellulose and hemicelluloses. Cellulosome assembly requires that a non-catalytic dockerin module found in cellulosomal enzymes binds to one of the various cohesin domains located in a large molecular scaffold called Scaffoldin. A diversity of cohesin -dockerin binding specificities have been described, the combination of which may result in complex plant cell wall degrading systems, maximising the synergy between enzymes in order to improve catalytic efficiency. Structural studies have allowed the spatial flexibility inherent to the cellulosomal system to be determined. Recent progress achieved from the study of the fundamental cohesin and dockerin units involved in cellulosome assembly will be reviewed.

Madeira, D., L. Narciso, H. N. Cabral, C. Vinagre, and M. S. Diniz. "HSP70 production patterns in coastal and estuarine organisms facing increasing temperatures." Journal of Sea Research. 73 (2012): 137-147. AbstractWebsite
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Vinagre, C., D. Madeira, L. Narciso, H. N. Cabral, and M. S. Diniz. "Impact of climate change on coastal versus estuarine nursery areas: Cellular and whole-animal indicators in juvenile seabass Dicentrarchus labrax." Marine Ecology Progress Series. 464 (2012): 237-243. AbstractWebsite
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Inácio, David, João Pina, João Martins, Mário Ventim Neves, and Alfredo Álvarez. "Lumped Parameters Equivalent Circuit of a Superconducting Hysteresis Motor." EUCAS Conference 2011. Vol. 36. 2012. 975-979. Abstract

The potential advantage of using superconducting materials in electrical devices is well described in the literature. The electromagnetic properties of these materials make them unique for several applications, such as, e.g. electrical machines and drives, fault current applications, or superconducting magnetic energy storage. In the development of electromechanical conversion devices, superconducting materials are used foreseeing mainly a decrease in the device dimensions or a performance improvement for the same active volume. To guarantee a good application of this kind of materials it is important to describe and model the phenomena that characterize their operation under different regimes. In this paper, a study based in FEM simulations of a motor with bulk superconductor in the rotor is carried out, with the purpose of understand, quantify and qualify which phenomena are present in the different regimes of the motor, leading to obtaining an equivalent electrical circuit with lumped parameters.

Cardoso, Alberto, A. Santos, G. N. N. V. Nunes, and P. Gil. "A Multi-Agent Approach for Outlier Accommodation in Wireless Sensor and Actuator Networks." Controlo2012 - 10th Portuguese Conference on Automatic Control. n/a 2012. Abstract
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Bras, Joana L. A., Victor D. Alves, Ana Luisa Carvalho, Shabir Najmudin, Jose A. M. Prates, Luis M. A. Ferreira, David N. Bolam, Maria Joao Romao, Harry J. Gilbert, and Carlos M. G. A. Fontes. "Novel Clostridium thermocellum Type I Cohesin-Dockerin Complexes Reveal a Single Binding Mode." The Journal of biological chemistry. 287 (2012): 44394-405.Website
Martins, Rodrigo F. P., Arman Ahnood, Nuno Correia, Luís MNP Pereira, Raquel Barros, Pedro MCB Barquinha, Ricardo Costa, Isabel M. M. Ferreira, Arokia Nathan, and Elvira EMC Fortunato. "Recyclable, Flexible, Low‐Power Oxide Electronics." Advanced Functional Materials (2012). Abstract
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b Neves, N.a b, Barros Antunes Ferreira Calado Fortunato Martins R. a E. a. "Sintering behavior of nano- and micro-sized ZnO powder targets for rf magnetron sputtering applications." Journal of the American Ceramic Society. 95 (2012): 204-210. AbstractWebsite

In this work, the nonisothermal sintering behavior of as-received commercial high purity ZnO micrometric (m-ZnO), submicrometric (sm-ZnO) and nanometric (n-ZnO) powders was studied. The sintering behavior for sputtering target production was evaluated by changing the green density of samples from 62% of theoretical density (TD) to 35%. We observed that for n-ZnO powder, the maximum shrinkage rate (MSR) temperature (T MSR) was not affected by the green density, and that it was reached at lower temperatures (∼710°C) compared with m-ZnO and sm-ZnO powders. For these powders, the temperature of MSR increased from 803°C to 934°C and from 719°C to 803°C as TD changed from 62% to 35% TD, respectively. Small grain size (∼0.560 μm) and high density targets were obtained for n-ZnO when sintered at temperatures below the T MSR. Heating rate from 1°C to 15°C/min led to lower activation energy for n-ZnO (∼201 ± 3 kJ/mol) than for the submicrometric (sm-ZnO) (∼332 ± 20 kJ/mol) and micrometric (m-ZnO) (∼273 ± 9 kJ/mol) powders. Using the model proposed by Bannister and Woolfrey, an n value of 0.75 was found, which was correlated with a combination of viscous flow and volume diffusion mechanisms that should control the initial stage of n-ZnO sintering. No significant differences were observed for n-ZnO powder in terms of density when the size of targets (scale-up effect) was increased, while in the case of m-ZnO and sm-ZnO, a delay in the densification was observed, which was related to the higher sinterability of n-ZnO powder. Two inches ZnO ceramic targets with different particle sizes and final densities were used in an rf magnetron sputtering system to produce ZnO films under the same deposition conditions. Films with thickness around 100 nm and good uniformity were produced using those targets, and no variation was observed in the optical and morphological properties. However, low electrical resistivity (1.4 Omega;·cm) films were obtained with n-ZnO targets, which could be explained in terms of a nonstoichiometric Zn:O composition of the started powders. © 2011 The American Ceramic Society.

Neves, Nuno, Raquel Barros, Elsa Antunes, Isabel Ferreira, Joao Calado, Elvira Fortunato, and Rodrigo Martins. "Sintering Behavior of Nano‐and Micro‐Sized ZnO Powder Targets for rf Magnetron Sputtering Applications." Journal of the American Ceramic Society. 95.1 (2012): 204-210. Abstract
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Pereira, AS, C. G. Timoteo, M. Guilherme, F. Folgosa, S. G. Naik, A. G. Duarte, BH HUYNH, and P. Tavares. "Spectroscopic Evidence for and Characterization of a Trinuclear Ferroxidase Center in Bacterial Ferritin from Desulfovibrio vulgaris Hildenborough." Journal of the American Chemical Society. 134 (2012): 10822-10832. AbstractWebsite

Ferritins are ubiquitous and can be found in practically all organisms that utilize Fe. They are composed of 24 subunits forming a hollow sphere with an inner cavity of similar to 80 angstrom in diameter. The main function of ferritin is to oxidize the cytotoxic Fe2+ ions and store the oxidized Fe in the inner cavity. It has been established that the initial step of rapid oxidation of Fe2+ (ferroxidation) by H-type ferritins, found in vertebrates, occurs at a diiron binding center, termed the ferroxidase center. In bacterial ferritins, however, X-ray crystallographic evidence and amino acid sequence analysis revealed a trinuclear Fe binding center comprising a binuclear Fe binding center (sites A and B), homologous to the ferroxidase center of H-type ferritin, and an adjacent mononuclear Fe binding site (site C). In an effort to obtain further evidence supporting the presence of a trinuclear Fe binding center in bacterial ferritins and to gain information on the states of the iron bound to the trinuclear center, bacterial ferritin from Desulfovibrio vulgaris (DvFtn) and its E130A variant was loaded with substoichiometric amounts of Fe2+, and the products were characterized by Mossbauer and EPR spectroscopy. Four distinct Fe species were identified: a paramagnetic diferrous species, a diamagnetic diferrous species, a mixed valence Fe2+Fe3+ species, and a mononuclear Fe2+ species. The latter three species were detected in the wild-type DvFtn, while the paramagnetic diferrous species was detected in the E130A variant. These observations can be rationally explained by the presence of a trinuclear Fe binding center, and the four Fe species can be properly assigned to the three Fe binding sites. Further, our spectroscopic data suggest that (1) the fully occupied trinuclear center supports an all ferrous state, (2) sites B and C are bridged by a mu-OH group forming a diiron subcenter within the trinuclear center, and (3) this subcenter can afford both a mixed valence Fe2+Fe3+ state and a diferrous state. Mechanistic insights provided by these new findings are discussed and a minimal mechanistic scheme involving O-O bond cleavage is proposed.

de Calheiros Velozo, A., G. Lavareda, C. Nunes de Carvalho, and A. Amaral. "Thermal dehydrogenation of amorphous silicon deposited on c-Si: Effect of the substrate temperature during deposition." PHYSICA STATUS SOLIDI C: CURRENT TOPICS IN SOLID STATE PHYSICS, VOL 9, NO 10-11. Eds. S. Pizzini, G. Kissinger, H. YamadaKaneta, and J. Kang. Vol. 9. Physica Status Solidi C-Current Topics in Solid State Physics, 9. European Mat Res Soc (E-MRS), 2012. 2198-2202. Abstract

Samples of doped and undoped a-Si: H were deposited at temperatures ranging from 100 degrees C to 350 degrees C and then submitted to different dehydrogenation temperatures (from 350 degrees C to 550 degrees C) and times (from 1 h to 4 h). a-Si: H films were characterised after deposition through the measurements of specific material parameters such as: the optical gap, the conductivity at 25 degrees C, the thermal activation energy of conductivity and its hydrogen content. Hydrogen content was measured after each thermal treatment. Substrate dopant contamination from phosphorus-doped a-Si thin films was evaluated by SIMS after complete dehydrogenation and a junction depth of 0.1 mu m was obtained. Dehydrogenation results show a strong dependence of the hydrogen content of the as-deposited film on the deposition temperature. Nevertheless, the dehydrogenation temperature seems to determine the final H content in a way almost independent from the initial content in the sample. H richer films dehydrogenate faster than films with lower hydrogen concentration. (C) 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim

de Calheiros Velozo, A., G. Lavareda, C. Nunes de Carvalho, and A. Amaral. "Thermal dehydrogenation of amorphous silicon deposited on c-Si: Effect of the substrate temperature during deposition." PHYSICA STATUS SOLIDI C: CURRENT TOPICS IN SOLID STATE PHYSICS, VOL 9, NO 10-11. Eds. S. Pizzini, G. Kissinger, H. YamadaKaneta, and J. Kang. Vol. 9. Physica Status Solidi C-Current Topics in Solid State Physics, 9. European Mat Res Soc (E-MRS), 2012. 2198-2202. Abstract

Samples of doped and undoped a-Si: H were deposited at temperatures ranging from 100 degrees C to 350 degrees C and then submitted to different dehydrogenation temperatures (from 350 degrees C to 550 degrees C) and times (from 1 h to 4 h). a-Si: H films were characterised after deposition through the measurements of specific material parameters such as: the optical gap, the conductivity at 25 degrees C, the thermal activation energy of conductivity and its hydrogen content. Hydrogen content was measured after each thermal treatment. Substrate dopant contamination from phosphorus-doped a-Si thin films was evaluated by SIMS after complete dehydrogenation and a junction depth of 0.1 mu m was obtained. Dehydrogenation results show a strong dependence of the hydrogen content of the as-deposited film on the deposition temperature. Nevertheless, the dehydrogenation temperature seems to determine the final H content in a way almost independent from the initial content in the sample. H richer films dehydrogenate faster than films with lower hydrogen concentration. (C) 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim

Madeira, D., L. Narciso, H. N. Cabral, M. S. Diniz, and C. Vinagre. "Thermal tolerance of the crab Pachygrapsus marmoratus: Intraspecific differences at a physiological (CTMax) and molecular level (Hsp70)." Cell Stress and Chaperones. 17 (2012): 707-716. AbstractWebsite
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Núñez, C., J. F. Lodeiro, M. Diniz, and M. Galesio. "Versatile Schiff-base hydrazone fluorescent receptors: Synthesis, spectroscopy and complexation studies." Inorganica Chimica Acta. 380 (2012): 40-49. AbstractWebsite
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Neagu, B., R. Chen, E. R. Neagu, and C. Dias. "Voltage, electric field and current density distributions around a commonly used deep brain stimulation electrode." Movement Disorders. 27 (2012): S209-S210. AbstractWebsite
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Inês, Cunha, Marques João Paulo, Gil Luís, Neagu E. R., Dias C. J., Marat-Mendes J. N., and Lança M. C. "Water Content Control to Improve Space Charge Storage in a Cork Derivative." Materiais2011. Materials Science Forum. 2012. Abstract
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M.C., Lan, Cunha I., Marques Jo Paulo, GIL L., NEAGU E.R., DIAS C.J., and Marat-Mendes Jose N. "Water Content Control to Improve Space Charge Storage in a Cork Derivative." 730-732 (2012): 395-400. Abstract
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Gawande, Manoj B., Alexandre Velhinho, Isabel D. Nogueira, C. A. A. Ghumman, O. M. N. D. Teodoro, and Paula S. Branco. "{A facile synthesis of cysteine – ferrite magnetic nanoparticles for application in multicomponent reactions — a sustainable protocol}." RSC Advances. 2 (2012): 6144-6149. Abstract

A facile, simple and environmentally friendly Fe3O4–cysteine MNP was synthesized without any additive or additional source of linkers. Fe3O4–cysteine MNPs were successfully used for the synthesis of b-amino carbonyl and hydroquinoline compounds, which were obtained in excellent yields via multicomponent reactions. Magnetic organocatalysts can be easily recovered by simple magnetic decantation and their catalytic activity remains unaltered after 9 consecutive cycles, making them environmen- tally friendly and widely applicable due to their efficiency, ease of handling, and cost effectiveness.

Gawande, Manoj B., Anuj Rathi, Isabel D. Nogueira, C. a. a. Ghumman, N. Bundaleski, O. M. N. D. Teodoro, and Paula S. Branco. "{A Recyclable Ferrite-Co Magnetic Nanocatalyst for the Oxidation of Alcohols to Carbonyl Compounds}." ChemPlusChem. 77 (2012): 865-871. AbstractWebsite

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Neto, M. a, E. L. Silva, C. a Ghumman, O. M. Teodoro, A. J. S. Fernandes, F. J. Oliveira, and R. F. Silva. "{Composition profiles and adhesion evaluation of conductive diamond coatings on dielectric ceramics}." Thin Solid Films. 520 (2012): 5260-5266. AbstractWebsite

Sintered silicon nitride (Si3N4) ceramic substrates were investigated as dielectric substrates for the growth of metal-like boron-doped nanocrystalline diamond (NCD) and microcrystalline diamond coatings via the Hot Filament Chemical Vapor Deposition (HFCVD) technique. The structural, electrical and chemical properties of both the ceramic substrates and the diamond coatings may potentiate their applicability in particular in harsh environments and highly demanding situations. Boron doping was achieved via a boron oxide solution in ethanol dragged into the reaction chamber with argon. The coatings were characterized by scanning elec- tron microscopy, UV $μ$-Raman scattering, X-ray diffraction, time-of-flight secondary ion mass spectroscopy, Brale indentation for adhesion evaluation and two-point contact probe for resistivity measurements. The HFCVD technique led to a maximal growth rate of about 1 $μ$m/h. Several metal-like boron doped diamond coatings were obtained. It was found that at lower substrate temperature, lower system pressure and higher methane concentration, the resistivity of the conducting NCD coatings is about 3 orders of magnitude higher when compared with samples obtained with higher substrate temperature, higher system pressure and lower methane concentration. Nevertheless, for every metal-like boron-doped coating the use of the Si3N4 ceramic substrate guaranteed a superior adhesion level. ©

Gawande, Manoj B., Anuj K. Rathi, Paula S. Branco, Isabel D. Nogueira, Alexandre Velhinho, Janhavi J. Shrikhande, Utkarsha U. Indulkar, Radha V. Jayaram, Amjad C. A. Ghumman, Nenad Bundaleski, and Orlando M. N. D. Teodoro. "{Regio- and Chemoselective Reduction of Nitroarenes and Carbonyl Compounds over Recyclable Magnetic Ferrite À Nickel Nanoparticles ( Fe 3 O 4 À Ni ) by Using Glycerol as a Hydrogen Source}." Chemistry European Journal (2012): 12628-12632. Abstract

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Turner, N. J., B. M. Sicari, T. J. Keane, R. Londono, P. M. Crapo, S. Tottey, R. Matsushima, Y. Shimatsu, K. Nam, T. Kimura, and T. Fujisato. "{Tissue Engineering and Regenerative Medicine}." Journal of Tissue Engineering and Regenerative Medicine. 6 (2012): 1-429. AbstractWebsite
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2011
Mancas, M., Madhkour R., De Beul D., Leroy J., Riche N., Rybarczyk Y., and Zajéga F. "Kinact: a saliency-based social game." QPSR of the Numediart Research Program. 4.3 (2011): 65-70.copy.pdf