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2012
Carvalho, T., V. Augusto, A. R. Brás, N. M. T. Lourenço, CAM Afonso, S. Barreiros, N. T. Correia, P. Vidinha, E. J. Cabrita, M. Dionísio, and B. Roling. "Understanding the Ion Jelly Conductivity Mechanism." Journal of Physical Chemistry B. 116 (2012): 2664-2676. Abstract

The properties of the light flexible device, ion jelly, which combines gelatin with an ionic liquid (IL) were recently reported being promising to develop safe and highly conductive electrolytes. This article aims for the understanding of the ion jelly conductive mechanism using dielectric relaxation spectroscopy (DRS) in the frequency range 10−1−106 Hz; the study was complemented with differential scanning calorimetry (DSC) and pulse field gradient nuclear magnetic resonance (PFG NMR) spectroscopy. The room temperature ionic liquid 1-butyl-3-methylimmidazolium dicyanamide (BMIMDCA) used as received (1.9% w/w water content) and with 6.6% (w/w) of water content and two ion jellies with two different ratios BMIMDCA/gelatin/water % (w/w), IJ1 (41.1/46.7/12.2) and IJ3 (67.8/25.6/6.6), have been characterized. A glass transition was detected by DSC for all materials allowing for classifying them as glass formers. For the ionic liquid, it was observed that the glass transition temperature decreases with the increase of water content. While in subsequent calorimetric runs crystallization was observed for BMIMDCA with negligible water content, no crystallization was detected for any of the ion jelly materials upon themal cycling. To the dielectric spectra of all tested materials, both dipolar relaxation and conductivity contribute; at the lowest frequencies, electrode and interfacial polarization highly dominate. Conductivity, which manifests much more intensity relative to dipolar reorientations, strongly evidences subdiffusive ion dynamics at high frequencies. From dielectric measures, transport properties as mobility and diffusion coefficients were extracted. Data treatment was carried out in order to deconvolute the average diffusion coefficients estimated from dielectric data in its individual contributions of cations (D+) and anions (D−). The D+ values thus obtained for IJ3, the ion jelly with the highest IL/gelatin ratio, cover a large temperature range up to room temperature and revealed excellent agreement with direct measurements from PFG NMR, obeying to the same VFT equation. For BMIMDCA6.6%water, which has the same water amount as IJ3, the diffusion coefficients were only estimated from DRS measurements over a limited temperature range; however, a single VFT equation describes both DRS and PFG NMR data. Moreover, it was found that the diffusion coefficients and mobility are similar for the ionic liquid and IJ3, which points to a role of both water and gelatin weakening the contact ion pair, facilitating the translational motion of ions and promoting its dissociation; nevertheless, it is conceivable that a critical composition of gelatin that leads to those properties. The VFT temperature dependence observed for the conductivity was found to be determined by a similar dependence of the mobility. Both conductivity and segmental motion revealed to be correlated as inferred by the relatively low values of the decoupling indexes. The obtained results show that ion jelly could be in fact a very promising material to design novel electrolytes for different electrochemical devices, having a performance close to the IL but presenting an additional stability regarding electrical measurements and resistance against crystallization relative to the bulk ionic liquid.

Barbosa, Rui, Diogo Dias, Nuno Lapa, and Benilde Mendes. "Using biomass ashes in concretes exposed to salted water and freshwater: mechanical and chemical properties." Advanced Materials Research. 587 (2012): 16-20. AbstractWebsite

The main aim of this work was to assess the possibility of using biomass ashes as substitutes for cement and natural aggregates in concretes without compromising their mechanical and chemical properties. Thirteen concrete formulations were prepared with different percentages of bottom and fly ashes produced at a forest biomass power plant. These formulations were submitted to mechanical compressive strength assays, after 28, 60 and 90 days of maturation. The reference formulation F1 that was produced without biomass ashes and one formulation incorporating fly and bottom ashes, F4, were selected for further characterization. After 90 days of maturation, the selected formulations were submitted to the leaching test described in the European Standard EN12457-2 (L/S ratio of 10 L/kg, in a batch extraction cycle of 24h) by using two different leaching agents: a synthetic marine medium (ASPM medium) and a synthetic freshwater medium (ISO 6341 medium). The eluates produced were submitted to chemical characterization which comprised a set of metals (As, Sb, Se, Cu, Zn, Ba, Hg, Cd, Mo, Pb, Ni, Cr, Cr VI, Al, Fe, Mg, Na, K and Ca), pH, SO42-, F-, dissolved organic carbon, chlorides, phenolic compounds and total dissolved solids. The substitution of 10% cement by fly ashes has not promoted the reduction of the compressive strength of concrete. The new formulation F4 has presented emission levels of chemical species similar or even lower to those observed for the reference formulation F1.

Brás, C. P., M. Fukushima, J. J. Júdice, and S. S. Rosa. "Variational Inequality Formulation of the Asymmetric Eigenvalue Complementarity Problem and Its Solution by Means of Gap Functions." Pacific Journal of Optimization. 8.(2) (2012): 197-215. AbstractWebsite

In this paper, the solution of the asymmetric eigenvalue complementarity problem (EiCP) is investigated by means of a variational inequality formulation. This problem is then solved by finding a stationary point of the gap function and the regularized gap function. A nonlinear programming formulation of the EiCP results from the gap function. A hybrid algorithm combining a projection technique and a modified Josephy-Newton method is proposed to solve the EiCP by finding a stationary point of the regularized gap function. Numerical results show that the proposed method can in general solve EiCPs efficiently.

Romain, Charles, Vitor Rosa, Christophe Fliedel, Frederic Bier, Frederic Hild, Richard Welter, Samuel Dagorne, and Teresa Aviles. "{Highly active zinc alkyl cations for the controlled and immortal ring-opening polymerization of epsilon-caprolactone}." {DALTON TRANSACTIONS}. {41} (2012): {3377-3379}. Abstract

{Zinc alkyl cations supported by N,N-BIAN-type bidentate ligands were found to be highly active in the immortal ROP of epsilon-caprolactone to yield narrowly disperse and chain length-controlled poly(epsilon-caprolactone), whether in solution or bulk polymerization conditions.}

Neves, Nuno, Raquel Barros, Elsa Antunes, João Calado, Elvira Fortunato, Rodrigo Martins, and Isabel Ferreira. "Aluminum doped zinc oxide sputtering targets obtained from nanostructured powders: Processing and application." Journal of the European Ceramic Society (2012). Abstract
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Barbosa, I. C. J., C. N. F. Simões, Tiago A. N. Silva, and M. A. R. Loja Analysis and Design of Beam Structures Made of Agro Waste Composite Materials. Proc. da 1ª Conferência Nacional sobre Computação Simbólica no Ensino e na Investigação (CSEI 2012)., 2012. Abstract
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Soares, Paula I. P., Isabel M. M. Ferreira, Rui A. G. B. N. Igreja, Carlos M. M. Novo, and Joao P. M. R. Borges. "Application of Hyperthermia for Cancer Treatment: Recent Patents Review." Recent Patents on Anti-Cancer Drug Discovery. 7 (2012): 64-73. Abstract

Cancer is one of the main causes of death in the world and its incidence increases every day. Current treatments are insufficient and present many breaches. Hyperthermia is an old concept and since early it was established as a cancer treatment option, mainly in superficial cancers. More recently the concept of intracellular hyperthermia emerged wherein magnetic particles are concentrated at the tumor site and remotely heated using an applied magnetic field to achieve hyperthermic temperatures (42-45 degrees C). Many patents have been registered in this area since the year 2000. This review presents the most relevant information, organizing them according to the hyperthermic method used: 1) external RadioFrequency devices; 2) hyperthermic perfusion; 3) frequency enhancers; 4) apply heating to the target site using a catheter; 5) injection of magnetic and ferroelectric particles; 6) injection of magnetic nanoparticles that may carry a pharmacological active drug. The use of magnetic nanoparticles is a very promising treatment approach since it may be used for diagnostic and treatment. An ideal magnetic nanoparticle would be able to detect and diagnose the tumor, carry a pharmacological active drug to be delivered in the tumor site, apply hyperthermia through an external magnetic field and allow treatment monitoring by magnetic resonance imaging.

Bastos, I., L. B. Oliveira, JP Oliveira, J. Goes, and M. M. Silva. "Balun LNA with continuously controllable gain and with noise and distortion cancellation." Circuits and Systems (ISCAS), 2012 IEEE International Symposium on. IEEE, 2012. 2143-2146. Abstract
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Bahubalindruni, G.a, Tavares Barquinha Duarte Martins Fortunato De Oliveira V. G. a P. "Basic analog circuits with a-GIZO thin-film transistors: Modeling and simulation." 2012 International Conference on Synthesis, Modeling, Analysis and Simulation Methods and Applications to Circuit Design, SMACD 2012. 2012. 261-264. Abstract

This paper addresses a modeling and simulation methodology for analog circuit design with amorphous-GIZO thin-film transistors (TFTs). To reach an effective circuit design flow, with commercially available tools, a TFT model has been first developed with an artificial neural network (ANN). Multilayer perceptron with backpropagation algorithm has been adopted to model the static behavior of the TFT devices, for different aspect ratios. The model was then implemented in Verilog-A, to allow a quick instantiation in circuit. Simulations using Cadence Spectre are performed to validate the model. On a second phase, simulation results of basic analog circuits, with this ANN model, are verified against the actual functional results, namely an adder, subtractor, and current mirror circuit. Results demonstrate not only the ANN model accuracy and compatibility with dc and transient analysis, but also show the a-GIZO TFT capability to perform analog operations. © 2012 IEEE.

Graham, Lisa M., Vandana Gupta, Georgia Schafer, Delyth M. Reid, Matti Kimberg, Kevin M. Dennehy, William G. Hornsell, Reto Guler, Maria A. Campanero-Rhodes, Angelina S. Palma, Ten Feizi, Stella K. Kim, Peter Sobieszczuk, Janet A. Willment, and Gordon D. Brown. "The C-type Lectin Receptor CLECSF8 (CLEC4D) Is Expressed by Myeloid Cells and Triggers Cellular Activation through Syk Kinase." Journal of Biological Chemistry. 287 (2012): 25964-25974. Abstract
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PerdigãO, J. a, A. M. b Pinto, R. C. C. c Monteiro, F. M. c Braz Fernandes, P. b Laranjeira, and J. P. c Veiga. "Degradation of dental ZrO 2-based materials after hydrothermal fatigue. part I: XRD, XRF, and FESEM analyses." Dental Materials Journal. 31 (2012): 256-265. AbstractWebsite

The aim was to investigate the effect of simulated low-temperature degradation (s-LTD) and hydrothermal fatigue on the degradation of three ZrO2-based dental materials. Lava, IPS, and NanoZr discs were randomly assigned to (1) Control-Storage in distilled water at 37°C; (2) Aging at 134°C for 5 h (s-LTD); (3) Thermocycling in saliva for 30,000 cycles (TF). XRD revealed that ZrO 2 m phase was identified in all groups but TF increased the m phase only for Lava. Under the FESEM, Lava showed no alterations under s-LTD, but displayed corrosion areas up to 60 μm wide after TF. We conclude that TF accelerated the degradation of Lava through an increase in the m phase and grain pull-out from the material surface.

Perdigao, Jorge, Ana M. Pinto, Regina C. C. Monteiro, Francisco M. BRAZ FERNANDES, Pedro Laranjeira, and Joao P. Veiga. "Degradation of dental ZrO2-based materials after hydrothermal fatigue. Part I: XRD, XRF, and FESEM analyses." Dental Materials Journal. 31 (2012): 256-265. Abstract
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Cardoso, Alberto, M. T. Restivo, P. Cioga, M. Delgado, J. N. Monsanto, J. Bicker, E. Nunes, and P. Gil. "Demonstration of Online Educational Modules with Online Experiments." REV2012 - Remote Engineering & Virtual Instrumentation. n/a 2012. Abstract
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Palma, Angelina S., Yan Liu, Yibing Zhang, Hongtao Zhang, Ana S. Luis, Ana Luisa Carvalho, Harry J. Gilbert, Alisdair Boraston, Carlos M. G. A. Fontes, Wengang Chai, and Ten Feizi. "Designer-oligosaccharide microarrays to decipher ligands in mammalian and prokaryotic glucan-recognition systems." Glycobiology. 22 (2012): 1612-1613. Abstract
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Bernacka-Wojcik, I., AC Vaz, Ivo Martinho, D. Barata, P. Simões, PJ Wojcik, T. Busani, A. Oliva, P. Lopes, L. Hilliou, and others. "Development of microfluidic devices for biosensors." II Jornadas do CENIMAT (2012): 94. Abstract
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Soares, P. I. P., S. J. R. Dias, C. M. M. Novo, I. M. M. Ferreira, and J. P. Borges. "Doxorubicin vs. ladirubicin: methods for improving osteosarcoma treatment." Mini Reviews in Medicinal Chemistry. 12.12 (2012): 1239-1249. Abstract
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Valtchev, Stanimir, Elena Baikova, and Luis Jorge. "Electromagnetic field as the wireless transporter of energy." Facta universitatis - series: Electronics and Energetics. 25 (2012): 171-181. 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.

Trindade, Ana C., João P. Canejo, Pedro Patrício, Pedro Brogueira, Paulo I. Teixeira, and Maria Helena Godinho. "Hierarchical wrinkling on elastomeric Janus spheres." Journal of Materials Chemistry. 22.41 (2012): 22044-22049. Abstract
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Trindade, Ana C., Joao P. Canejo, Pedro Patricio, Pedro Brogueira, Paulo I. Teixeira, and Maria Helena Godinho. "Hierarchical wrinkling on elastomeric Janus spheres (vol 22, pg 22044, 2012)." JOURNAL OF MATERIALS CHEMISTRY. 22.48 (2012): 25500. Abstract
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Filonovich, Sergej Alexandrovich, Hugo Águas, Tito Busani, António Vicente, Andreia Araújo, Diana Gaspar, Marcia Vilarigues, Joaquim Leitão, Elvira Fortunato, and Rodrigo Martins. "Hydrogen plasma treatment of very thin p-type nanocrystalline Si films grown by RF-PECVD in the presence of B (CH3) 3." Science and Technology of Advanced Materials. 13.4 (2012): 045004. Abstract
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Filonovich, Sergej Alexandrovich, Hugo Aguas, Tito Busani, António Vicente, Andreia Araújo, Diana Gaspar, Marcia Vilarigues, Joaquim Leitao, Elvira Fortunato, and Rodrigo Martins. "Hydrogen plasma treatment of very thin p-type nanocrystalline Si films grown by RF-PECVD in the presence of B (CH3) 3." Science and Technology of Advanced Materials. 13 (2012): 045004. Abstract
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Zarrouk, Olfa, Rita Francisco, Marta Pinto-Marijuan, Ricard Brossa, Raquen Raissa Santos, Carla Pinheiro, Joaquim Miguel Costa, Carlos Lopes, and Maria Manuela Chaves. "Impact of irrigation regime on berry development and flavonoids composition in Aragonez (Syn. Tempranillo) grapevine." Agricultural Water Management. 114 (2012). AbstractWebsite
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Zarrouk, Olfa, Rita Francisco, Marta Pinto-Marijuan, Ricard Brossa, Raquen Raissa Santos, Carla Pinheiro, Joaquim Miguel Costa, Carlos Lopes, and Maria Manuela Chaves. "Impact of irrigation regime on berry development and flavonoids composition in Aragonez (Syn. Tempranillo) grapevine." Agricultural Water Management. 114 (2012). AbstractWebsite
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Barroso, Telma, Raquel Viveiros, Margarida Coelho, Teresa Casimiro, Ana M. Botelho do Rego, and Ana Aguiar-Ricardo. "Influence of poly(N-isopropylacrylamide) and poly(N,N′-diethyl acrylamide) coatings on polysulfone/polyacrylonitrile-based membranes for protein separation." Polymers for Advanced Technologies. 23 (2012): 1381-1393. AbstractWebsite

Herein we describe the design and the assembly of temperature sensitive polysulfone (PS)/polyacrylonitrile (PAN) blend membranes using supercritical fluid technology. Blended membranes were prepared using the CO2-assisted phase inversion method, and their pores were coated with two thermoresponsive hydrogels-poly(N-isopropylacrylamide) (PNIPAAm) and poly(N,N′-diethylacrylamide) (PDEAAm). Permeation experiments of bovine serum albumin (BSA) and lysozyme (LYS) solutions were used to evaluate the performance and temperature-responsive behavior of coated membranes. While membranes coated with PNIPAAm presented similar protein permeation profiles at temperatures below and above its lower critical solution temperature, PDEAAm coating imparted a temperature-responsive behavior to PS/PAN (90:10) membranes and selective permeation of proteins with different sizes. Copyright © 2011 John Wiley & Sons, Ltd.