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2014
Merino, E. G., G. Lavareda, P. Brogueira, A. Amaral, C. Nunes de Carvalho, and PL Almeida. "InOx thin films deposited by plasma assisted evaporation: Application in light shutters." VACUUM. 107 (2014): 116-119. Abstract

An integration of undoped InOx and commercial ITO thin films into laboratory assembled light shutter devices is made. Accordingly, undoped transparent conductive InOx thin films, about 100 nm thick, are deposited by radiofrequency plasma enhanced reactive thermal evaporation (rf-PERTE) of indium teardrops with no intentional heating of the glass substrates. The process of deposition occurs at very low deposition rates (0.1–0.3 nm/s) to establish an optimized reaction between the oxygen plasma and the metal vapor. These films show the following main characteristics: transparency of 87% (wavelength, λ = 632.8 nm) and sheet resistance of 52 Ω/sq; while on commercial ITO films the transparency was of 92% and sheet resistance of 83 Ω/sq. The InOx thin film surface characterized by AFM shows a uniform grain texture with a root mean square surface roughness of Rq∼2.276 nm. In contrast, commercial ITO topography is characterized by two regions: one smoother with Rq∼0.973 nm and one with big grains (Rq∼3.617 nm). For the shutters assembled using commercial ITO, the light transmission coefficient (Tr) reaches the highest value (Trmax) of 89% and the lowest (Trmin) of 1.3% [13], while for the InOx shutters these values are 80.1% and 3.2%, respectively. Regarding the electric field required to achieve 90% of the maximum transmission in the ON state (Eon), the one presented by the devices assembled with commercial ITO coated glasses is 2.41 V/μm while the one presented by the devices assembled with InOx coated glasses is smaller, 1.77 V/μm. These results corroborate the device quality that depends on the base materials and fabrication process used.

Merino, E. G., G. Lavareda, P. Brogueira, A. Amaral, C. Nunes de Carvalho, and PL Almeida. "InOx thin films deposited by plasma assisted evaporation: Application in light shutters." VACUUM. 107 (2014): 116-119. Abstract

{An integration of undoped InOx and commercial ITO thin films into laboratory assembled light shutter devices is made. Accordingly, undoped transparent conductive InOx thin films, about 100 nm thick, are deposited by radiofrequency plasma enhanced reactive thermal evaporation (rf-PERTE) of indium teardrops with no intentional heating of the glass substrates. The process of deposition occurs at very low deposition rates (0.1-0.3 nm/s) to establish an optimized reaction between the oxygen plasma and the metal vapor. These films show the following main characteristics: transparency of 87% (wavelength

Valtchev, Stanimir, Rui Neves-Medeiros, Anastassia Krusteva, George Gigov, and Plamen Avramov. "A wireless energy transceiver based on induction heating equipment." 2014 16th International Power Electronics and Motion Control Conference and Exposition. Institute of Electrical {&} Electronics Engineers ({IEEE}), 2014. Abstract
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Moura, I., C. Carreira, S. Pauleta, R. F. Nunes, J. J. Moura, S. Ramos, S. Dell'acqua, and O. Einsle. "INSIGHTS INTO THE CATALYTICCYCLE OF Pseudomonas nautica NITROUS OXIDE REDUCTASE." Journal of Biological Inorganic Chemistry. Vol. 19. J Biol Inorg Chem, 19. 2014. S104. Abstract
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Altstadt, S. G., et al. "{$^{13,14}$B(n, $\gamma$) via Coulomb Dissociation for Nucleosynthesis towards the r-Process}." Nuclear Data Sheets. 120 (2014): 197-200. AbstractWebsite
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Maiti, B. K., L. B. Maia, K. Pal, B. Pakhira, T. Aviles, I. Moura, S. R. Pauleta, J. L. Nunez, A. C. Rizzi, CD Brondino, S. Sarkar, and J. J. Moura. "One electron reduced square planar bis(benzene-1,2-dithiolato) copper dianionic complex and redox switch by O2/HO(-)." Inorg Chem. 53 (2014): 12799-808. AbstractWebsite

The complex [Ph4P]2[Cu(bdt)2] (1(red)) was synthesized by the reaction of [Ph4P]2[S2MoS2CuCl] with H2bdt (bdt = benzene-1,2-dithiolate) in basic medium. 1(red) is highly susceptible toward dioxygen, affording the one electron oxidized diamagnetic compound [Ph4P][Cu(bdt)2] (1(ox)). The interconversion between these two oxidation states can be switched by addition of O2 or base (Et4NOH = tetraethylammonium hydroxide), as demonstrated by cyclic voltammetry and UV-visible and EPR spectroscopies. Thiomolybdates, in free or complex forms with copper ions, play an important role in the stability of 1(red) during its synthesis, since in its absence, 1(ox) is isolated. Both 1(red) and 1(ox) were structurally characterized by X-ray crystallography. EPR experiments showed that 1(red) is a Cu(II)-sulfur complex and revealed strong covalency on the copper-sulfur bonds. DFT calculations confirmed the spin density delocalization over the four sulfur atoms (76%) and copper (24%) atom, suggesting that 1(red) has a "thiyl radical character". Time dependent DFT calculations identified such ligand to ligand charge transfer transitions. Accordingly, 1(red) is better described by the two isoelectronic structures [Cu(I)(bdt2, 4S(3-,)*)](2-) <--> [Cu(II)(bdt2, 4S(4-))](2-). On thermodynamic grounds, oxidation of 1(red) (doublet state) leads to 1(ox) singlet state, [Cu(III)(bdt2, 4S(4-))](1-).

Nunes, D., A. Pimentel, P. Barquinha, P. A. Carvalho, E. Fortunato, and R. Martins. "Cu2O polyhedral nanowires produced by microwave irradiation." Journal of Materials Chemistry C. 2 (2014): 6097-6103. AbstractWebsite
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Santos, Lidia, Joana P. Neto, Ana Crespo, Daniela Nunes, Nuno Costa, Isabel M. Fonseca, Pedro Barquinha, Luis Pereira, Jorge Silva, Rodrigo Martins, and Elvira Fortunato. "WO3 Nanoparticle-Based Conformable pH Sensor." Acs Applied Materials & Interfaces. 6 (2014): 12226-12234. AbstractWebsite
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Barrocas, B., S. Sério, A. Rovisco, Y. Nunes, A. I. de Sá, Silva M. I. da Pereira, and Melo M. E. Jorge. "{Characterization and electrochemical behaviour of nanostructured calcium samarium manganite electrodes fabricated by RF-Magnetron Sputtering}." Electrochimica Acta. 137 (2014): 99-107. AbstractWebsite

Ca1-xSmxMnO3 (0≤x≤0.4) films were successfully fabricated on Indium Tin Oxide (ITO) coated quartz glass substrates by radio frequency magnetron sputtering technique (RF- magnetron sputtering) from compacted nanosized powder targets, and subsequent annealing at 800°C in air, for 6h. X-ray diffraction shows a pure typical perovskite phase for x≥0.1. Scanning electron microscopy and atomic force microscopy revealed that the film surface is dense, with low roughness, depending on the Sm content, even though a few cracks were observed. Crystallite size was found to decrease with the Sm content. The electrodes were characterized by cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS).The oxide electrode's capacitance was estimated using both techniques and the corresponding roughness factors evaluated. The values obtained from the two methods show a good agreement. A comparison between the voltammetric data and those referred in the literature allowed finding out that the redox reaction occurring at the electrode surface involves the pair Mn4+/Mn3+. EIS measurements confirm the voltammetric data and they also give additional information about the film porosity and the charge transfer resistance. This last parameter is associated with the oxidation and reduction of the pair Mn3+/Mn4+and after normalized by the roughness factor shows an increase with samarium content.

R., Póvoa, Lourenço N., Horta N., and Goes J. "A Cascode-Free Single-Stage Amplifier Using a Fully-Differential Folded Voltage-Combiner." 21st IEEE International Conference on Electronics Circuits and Systems. Marseille, France: IEEE, 2014.
N., Pereira, Goes J., Rodrigues M., and Faria P. "A New Mismatch-Insensitive 1.5-Bit MDAC with Unity Feedback-Factor and Enhanced Performance." 21st IEEE International Conference on Electronics Circuits and Systems. Marseille, France: IEEE, 2014.
de Melo, J. L. A., Querido F., Paulino N., and Goes J. A 0.4-V 410-nW opamp-less continuous-time ΣΔ modulator for biomedical applications. IEEE International Symposium on Circuits and Systems (ISCAS). Melbourne, Australia: IEEE, 2014.
Neves, S. O., P. Rodrigues, and M. P. Amado. "Contribution of the social sciences in the transformation of informal communities." 40th IAHS World Congress in Housing – Sustainable Housing Construction. 21 - ISBN: 978-989-98949-0-7. Funchal, Madeira - PT: IteCons - Universidade de Coimbra, 2014.
Neves, S. O., and M. P. Amado. "Incremental Housing as a method to the Sustainable Habitat ." 30th International PLEA . Vol. II - 1-8. Bangalore, India: Centre for Advanced Research in Building Science and Energy (CARBSE), CEPT University, 2014.
Sniatala, P., M. Naumowicz, J. L. A. de Melo, and Goes J. "A hybrid current-mode passive second-order continuous-time ΣΔ modulator." 21st. International Conference on Mixed Design of Integrated Circuits and Systems (MIXDES). Poland: IEEE, 2014.
e Nuno Mamede, Duarte Faria António Ramos. "Análise Numérica do Punçoamento em Lajes Fungiformes Pré-Esforçadas." 5ªs Jornadas Portuguesas de Engenharia de Estruturas, Encontro Nacional de Betão Estrutural 2014, 9º Congresso Nacional de Sismologia e Engenharia Sísmica. Lisbon: GPBE, 2014. Abstract

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N., Pereira, Goes J., Oliveira L. B., and Dinis R. Analog-to-Digital Converters with embedded IF mixing using variable reference voltages. IEEE International Symposium on Circuits and Systems (ISCAS). Melbourne, Australia, 2014.
Marcelo, Filipa, Fayna Garcia-Martin, Takahiko Matsushita, João Sardinha, Helena Coelho, Anneloes Oude-Vrielink, Christiane Koller, Sabine André, Eurico J. Cabrita, Hans-Joachim Gabius, Shin-Ichiro Nishimura, Jesús Jiménez-Barbero, and Javier F. Cañada. "Delineating binding modes of Gal/GalNAc and structural elements of the molecular recognition of tumor-associated mucin glycopeptides by the human macrophage galactose-type lectin." Chem. Eur. J.. in press (2014). Abstract

The human macrophage galactose-type lectin (hMGL) is a key physiological receptor for the carcinoma-associated Tn antigen (GalNAc-α-1-O-Ser/Thr) in mucins. We herein report NMR- and modeling-based data on the molecular recognition features of synthetic Tn-bearing glycopeptides by hMGL. Cognate epitopes on the sugar and matching key amino acids involved in the interaction have been identified by saturation transfer difference (STD) NMR spectroscopy. Only the amino acids close to the glycosylation site in the peptides are involved in lectin contact. Moreover, control experiments with non-glycosylated MUC1 peptides unequivocally showed that the sugar residue is essential for hMGL binding, as is Ca2+. The dissociation constants (Kd) have been estimated by STD titrations and/or STD competition experiments and show that Gal was a poor binder for hMGL, with a Kd in the mM range, while GalNAc and MUC1 Tn-glycopetides reached Kd values in the lower μM range. STD-based results suggested a distinct interacting epitope for the two monosaccharides. NMR data have been complemented with molecular dynamics simulations and Corcema- ST to establish a 3D view on the molecular recognition process between Gal, GalNAc and the Tn-presenting glycopeptides and hMGL. Gal and GalNAc have a dual binding mode with opposite trend of the main interaction pattern and the differences in affinity can be explained by additional hydrogen bonds and CH-π contacts involving exclusively the NHAc moiety.

Soares, PI, AM Alves, LC Pereira, JT Coutinho, IM Ferreira, CM Novo, and J. P. Borges. "Effects of surfactants on the magnetic properties of iron oxide colloids." J Colloid Interface Sci.. 419 (2014): 46-51. AbstractWebsite

Iron oxide nanoparticles are having been extensively investigated for several biomedical applications such as hyperthermia and magnetic resonance imaging. However, one of the biggest problems of these nanoparticles is their aggregation.

Taking this into account, in this study the influence of three different surfactants (oleic acid, sodium citrate and Triton X-100) each one with various concentrations in the colloidal solutions stability was analyzed by using a rapid and facile method, the variation in the optical absorbance along time.

The synthesized nanoparticles through chemical precipitation showed an average size of 9 nm and a narrow size distribution. X-ray diffraction pattern and Fourier Transform Infrared analysis confirmed the presence of pure magnetite. SQUID measurements showed superparamagnetic properties with a blocking temperature around 155 K. In addition it was observed that neither sodium citrate nor Triton X-100 influences the magnetic properties of the nanoparticles. On the other hand, oleic acid in a concentration of 64 mM decreases the saturation magnetization from 67 to 45 emu/g. Oleic acid exhibits a good performance as stabilizer of the iron oxide nanoparticles in an aqueous solution for 24 h, for concentrations that lead to the formation of the double layer.

Marinheiro, J., O. Mateus, A. Alaoui, F. Amani, M. Nami, and C. Ribeiro. "Elephas and other vertebrate fossils near Taghrout, Morocco." Journal of Vertebrate Paleontology. Program and Abstracts, 2014 (2014): 178.marinheiro_et_al._2014_elephas_and_other_vertebrate_fossils_near_taghrout.pdf
Cismaşiu, C., A. Narciso, and F. Amarante dos Santos. "Experimental Dynamic Characterization and Finite Element Updating of a Footbridge Structure." Journal of Performance of Constructed Facilities.10.1061/(ASCE)CF.1943-5509.0000615 (2014).Website
Cismaşiu, C., A. Narciso, and F. Amarante dos Santos. "Experimental Dynamic Characterization and Finite Element Updating of a Footbridge Structure." Journal of Performance of Constructed Facilities. 10.1061/(ASCE)CF.1943-5509.0000615 (2014). AbstractWebsite

Nowadays, modern analysis of Civil Engineering structures implies the use of increasingly sophisticated computer models, designed not only to predict the response of actual structures to different loadings, but also to simulate the effects of eventual modifications in their structural configuration. Nevertheless, it is often discovered that, when the numerical simulations are compared with experimental data, the degree of correlation is weak preventing the use of the FE models with confidence in further analyses. In such cases, FE updating techniques are available to correct the FE models, based on dynamic response records of the real structures. These updating processes usually consist of four phases: a preliminary FE modeling, an experimental modal identification, a manual sensitivity analysis and, finally, an updating of the FE model. The present paper presents all four phases of a successful updating process for the FE model of a footbridge structure. It is shown how the last phase of the process can be performed fully automatically, by coupling an optimization routine with a commercial FE analysis program.

Nowacki, B., Paulino N., and Goes J. A low power 4th order MASH switched-capacitor ΣΔ modulator using ultra incomplete settling. IEEE International Symposium on Circuits and Systems (ISCAS). Melbourne, Australia, 2014.
Nuno Gouveia, Ana Luísa Custódio, Duarte Faria António Ramos. "A Minimization Prodecure for the Determination of SFRC Tensile Behaviour." EngOpt 2014, 4th International Conference on Engineering Optimization. Lisbon 2014. Abstract

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Correia, Isabel, Stefan Nickel, and Francisco Saldanha-da-Gama. "Multi-product Capacitated Single-Allocation Hub Location Problems: Formulations and Inequalities." Networks and Spatial Economics. 14 (2014): 1-25. Abstract

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