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2013
Guerra, M., P. Amaro, C. I. Szabo, A. Gumberidze, P. Indelicato, and J. P. Santos. "Analysis of the charge state distribution in an ECRIS Ar plasma using high-resolution x-ray spectra." Journal of Physics B: Atomic, Molecular and Optical Physics. 46 (2013): 065701. AbstractWebsite

In this work, we obtained a charge state distribution inside an Ar plasma produced by an electron–cyclotron-resonance ion source. The processes that lead to the observed lines in x-ray spectra are identified and included in the simulated x-ray spectrum. The geometrical constraints of the flat double crystal spectrometer, used to measure the x-ray spectrum, are investigated as they are crucial for correctly obtaining the ion densities from the observed transition amplitudes. Multiple electron impact ionization is included, and a realistic electron velocity distribution is taken into account. The charge state distribution of the Ar ions is compared to measured extracted ionic currents.

Cismasiu, Corneliu, and Filipe Pimentel Amarante dos Santos. "Shape Memory Alloys in Structural Vibration Control. Research at UNIC/DEC/FCT/UNL." International Conference "Tradition and Innovation". 60 Years of Civil Engineering Higher Education in Transilvania. Cluj-Napoca, Romania: UTCN, 2013. c60.pdf
Faria, Gonçalo, Carlos Chastre, Válter Lúcio, and Ângela Nunes. "Compression behaviour of short columns made from cement-bonded particle board." Construction and Building Materials. 40 (2013): 60-69. AbstractWebsite

Cement bonded particle board (CBPB) is a composite material produced in plates consisting mainly of wood and cement, and may contain additives. This material is currently used in cladding, raised floors, dropped ceilings, prefabricated houses, office containers and various supplies to the building industry such as kitchens, bathrooms and furniture. It is composed of a type of wood Pinus pinaster and/or Pinus pinea, Portland cement type II, sodium silicate and aluminium sulphate. CBPB has been the subject of several studies with the purpose of enabling the use of other types of wood or even vegetable biomass, as the chemical compounds from wood (extractives and sugars) tend to inhibit of cement hydration. A study on the behaviour of short CBPB elements under compression was carried out in the Department of Civil Engineering of Universidade NOVA de Lisboa with the aim of enabling its use in structural elements. The study was supported by VIROC, the company which produces CBPB in Portugal. This paper presents and analyses the most significant results of a campaign of axial compression tests performed on 111 specimens of different heights and cross sections. The behaviour of CBPB specimens of varying slenderness was subjected to a more detailed analysis.

Pereira, P., M. Kotti, H. Fino, and M. Fakhfakh. "Metaheuristic algorithms comparison for the LC - Voltage controlled oscillators optimal design." 5th International Conference on Modeling, Simulation and Applied Optimization (ICMSAO). Hammamet, Tunisia 2013. 1-6. Abstract

The goal of this paper is to present a comparison among three known metaheuristics: Genetic Algorithm (GA), Particle Swarm Optimization (PSO) and Simulated Annealing (SA). For the comparison, the design of an LC - Voltage Controlled Oscillator (LC-VCO) is considered, where the minimization of both VCO phase noise and power consumption is envisaged. The objective of this comparison is to find the algorithm yielding the best solution. The validity of the solution obtained with each metaheuristic algorithm is checked against HSPICE/RF simulation results. Robustness checks for each algorithm are presented at the end of this paper.

Mateus, O., C. Neto de Carvalho, and A. A. Klompmaker. "Decapod crustacean body and ichnofossils from the Mesozoic of Portugal." 5th Symposium on Mesozoic and Cenozoic Decapod Crustaceans. Warszawa: Polish Geological Institute − National Research Institute & AGH University of Science and Technology, 2013. mateus_et_al_2013_crustacea_mesozoic_portugal_5th_decapod_crustaceans_meeting_2013.pdf
Araújo, Ricardo, Rui Castanhinha, Rui M. S. Martins, Octávio Mateus, Christophe Hendrickx, F. Beckmann, N. Schell, and L. C. Alves. "Filling the gaps of dinosaur eggshell phylogeny: Late Jurassic Theropod clutch with embryos from Portugal." Scientific Reports. 3.1924 (2013). Abstractaraujo_et_al_2013_filling_the_gaps_of_dinosaur_eggshell_phylogeny_late_jurassic_theropod_clutch_with_embryos_from_portugal.pdf

The non-avian saurischians that have associated eggshells and embryos are represented only by the sauropodomorph Massospondylus and Coelurosauria (derived theropods), thus missing the basal theropod representatives. We report a dinosaur clutch containing several crushed eggs and embryonic material ascribed to the megalosaurid theropod Torvosaurus. It represents the first associated eggshells and embryos of megalosauroids, thus filling an important phylogenetic gap between two distantly related groups of saurischians. These fossils represent the only unequivocal basal theropod embryos found to date. The assemblage was found in early Tithonian fluvial overbank deposits of the Lourinhã Formation in West Portugal. The morphological, microstructural and chemical characterization results of the eggshell fragments indicate very mild diagenesis. Furthermore, these fossils allow unambiguous association of basal theropod osteology with a specific and unique new eggshell morphology.

Correia, VG, M. Coelho, T. Barroso, V. P. Raje, V. D. B. Bonifácio, T. Casimiro, M. G. Pinho, and A. Aguiar-Ricardo. "Anti-biofouling 3D porous systems: the blend effect of oxazoline-based oligomers on chitosan scaffolds." Biofouling. 29.3 (2013): 273-282. AbstractWebsite
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Reis, T. C., I. J. Correia, and A. Aguiar-Ricardo. "Electrodynamic tailoring of self-assembled three-dimensional electrospun constructs." Nanoscale. 5.16 (2013): 7528-7536. AbstractWebsite
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Barroso, T., A. Hussain, A. C. A. Roque, and A. Aguiar-Ricardo. "Functional monolithic platforms: Chromatographic tools for antibody purification." Biotechnology Journal. 8.6 (2013): 671-681. AbstractWebsite
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Calado, L. M., C. M. Cordas, and J. P. Sousa. "Acemetacin and indomethacin detection using modified carbon microelectrodes." Analytical and Bioanalytical Electrochemistry. 5.6 (2013): 665-671. AbstractWebsite
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Li, L., P. S. Lopes, C. A. Figueira, C. S. B. Gomes, M. T. Duarte, V. Rosa, C. Fliedel, T. Avilés, and P. T. Gomes. "Cationic and neutral (Ar-BIAN)copper(I) complexes containing phosphane and arsane ancillary ligands: Synthesis, molecular structure and catalytic behaviour in cycloaddition reactions of azides and alkynes." European Journal of Inorganic Chemistry.9 (2013): 1404-1417. AbstractWebsite
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Nandy, Suman, Goncalo Goncalves, Joana Vaz Pinto, Tito Busani, Vitor Figueiredo, Luis Pereira, Rodrigo Ferrao Paiva Martins, and Elvira Fortunato. "Current transport mechanism at metal-semiconductor nanoscale interfaces based on ultrahigh density arrays of p-type NiO nano-pillars." Nanoscale. 5.23 (2013): 11699-11709. AbstractWebsite

The present work focuses on a qualitative analysis of localised I-V characteristics based on the nanostructure morphology of highly dense arrays of p-type NiO nano-pillars (NiO-NPs). Vertically aligned NiO-NPs have been grown on different substrates by using a glancing angle deposition (GLAD) technique. The preferred orientation of as grown NiO-NPs was controlled by the deposition pressure. The NiO-NPs displayed a polar surface with a microscopic dipole moment along the (111) plane (Tasker's type III). Consequently, the crystal plane dependent surface electron accumulation layer and the lattice disorder at the grain boundary interface showed a non-uniform current distribution throughout the sample surface, demonstrated by a conducting AFM technique (c-AFM). The variation in I-V for different points in a single current distribution grain (CD-grain) has been attributed to the variation of Schottky barrier height (SBH) at the metal-semiconductor (M-S) interface. Furthermore, we observed that the strain produced during the NiO-NPs growth can modulate the SBH. Inbound strain acts as an external field to influence the local electric field at the M-S interface causing a variation in SBH with the NPs orientation. This paper shows that vertical arrays of NiO-NPs are potential candidates for nanoscale devices because they have a great impact on the local current transport mechanism due to its nanostructure morphology.

Quintino, L., L. Liu, R. M. Miranda, R. J. C. Silva, A. Hu, and Y. Zhou. "Cutting NiTi with Femtosecond Laser." Advances in Materials Science and Engineering (2013): 98434. AbstractWebsite
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Cordas, C. M., A. G. Duarte, JJG Moura, and I. Moura. "Electrochemical behaviour of bacterial nitric oxide reductase - Evidence of low redox potential non-heme FeB gives new perspectives on the catalytic mechanism." Biochimica et Biophysica Acta - Bioenergetics. 1827.3 (2013): 233-238. AbstractWebsite
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Pinto, Joana V., Rita Branquinho, Pedro Barquinha, Eduardo Alves, Rodrigo Martins, and Elvira Fortunato. "Extended-Gate ISFETs Based on Sputtered Amorphous Oxides." Journal of Display Technology. 9.9 (2013): 729-734. AbstractWebsite
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Rosa, V., C. Fliedel, A. Ghisolfi, R. Pattacini, T. Avilés, and P. Braunstein. "Influence of a thioether function in short-bite diphosphine ligands on the nature of their silver complexes: Structure of a trinuclear complex and of a coordination polymer." Dalton Transactions. 42.34 (2013): 12109-12119. AbstractWebsite
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Gameiro, João, Tiago Cardoso, and Yves Rybarczyk. "Kinect-sign: teaching sign language to “listeners” through a game." Conference on Electronics, Telecomunications and Computers - CETC . Lisbon, Portugal, 2013. 141-159. Abstract

The sign language is widely used by deaf people around the globe. As the spoken languages, several sign languages do exist. The way sign language is learned by deaf people may have some details to be improved, but one can state that the existing learning mechanisms are effective when we talk about a deaf child, for example. The problem arises for the non-deaf persons that communicate with the deaf persons – the so-called listeners. If, for example, one couple has a new child that turns to be deaf, these two persons find a challenge to learn the sign language. In one hand, they cannot stop their working life, especially because of this sad news turns to be more costly, on the other hand, the existing mechanisms target the deaf-persons and are not prepared for the listeners. This paper proposes a new playful approach to help these listeners to learn the sign language. The proposal is a serious game composed of two modes: School-mode and Competition-mode. The first provides a school-like environment where the user learns the letter-signs and the second provides the user an environment used towards testing the learned skills. Behind the scenes, the proposal is based on two phases: 1 – the creation of a gestures library, relying on the Kinect depth camera; and 2 – the real-time recognition of gestures, by comparing what the depth camera information to the existing gestures previously stored in the library. A prototype system, supporting only the Portuguese sign language alphabet, was developed – the Kinect-Sign – and tested in a Portuguese Sign-Language school resulting in a joyful acceptance of the approach.

Figueiredo, V., JV Pinto, J. Deuermeier, R. Barros, E. Alves, R. Martins, and E. Fortunato. "p-Type CuxO Thin-Film Transistors Produced by Thermal Oxidation." Journal of Display Technology. 9.9 (2013): 6. AbstractWebsite
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Baltazar, LG, F. M. A. Henriques, F. Jorne, and M. T. Cidade. "Performance improvement of hydraulic lime based grouts for masonry consolidation: an experimental study." 131 (2013): 417-430. Abstract
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Branquinho, R., JV Pinto, T. Busani, P. Barquinha, L. Pereira, P. Viana Baptista, R. Martins, and E. Fortunato. "Plastic Compatible Sputtered Ta2O5 Sensitive Layer for Oxide Semiconductor TFT Sensors." Display Technology, Journal of. 9.9 (2013): 723-728. Abstract

The effect of post-deposition annealing temperature on the pH sensitivity of room temperature RF sputtered Ta2O5 was investigated. Structural and morphological features of these films were analyzed before and after annealing at various temperatures. The deposited films are amorphous up to 600 °C and crystallize at 700 °C in an orthorhombic phase. Electrolyte-insulator-semiconductor (EIS) field effect based sensors with an amorphous Ta2O5 sensing layer showed pH sensitivity above 50 mV/pH. For sensors annealed above 200 °C pH sensitivity decreased with increasing temperature. Stabilized sensor response and maximum pH sensitivity was achieved after low temperature annealing at 200 °C, which is compatible with the use of polymeric substrates and application as sensitive layer in oxides TFT-based sensors.

Ramos, A. M., S. Pereira, M. T. Cidade, G. Pereira, R. Branquinho, L. Pereira, R. Martins, and E. Fortunato. "Preparation and characterization of cellulose nanocomposite hydrogels as functional electrolytes." 242 (2013): 26-32. Abstract
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Miranda, R. M., T. G. Santos, J. Gandra, N. Lopes, and R. J. C. Silva. "Reinforcement strategies for producing functionally graded materials by friction stir processing in aluminium alloys." Journal of Materials Processing Technology. 213.9 (2013): 1609-1615. AbstractWebsite
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Bras, Ana, Fernando MA Henriques, and M. T. Cidade. "Rheological behaviour of hydraulic lime-based grouts. Shear-time and temperature dependence." 17.2 (2013): 223-242. Abstract
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Rybarczyk, Y., G. Carrasco, T. Cardoso, and Pavão I. Martins. "A serious game for multimodal training of physician novices." ICER2013 - 6th International Conference of Education, Research and Innovation. Seville, Spain: IATED, 2013. 4944-4949. Abstract

Serious games are usually applied to cognitive learning. However, the development of recent Natural User Interfaces (NUI) enables us to use serious games for a more holistic training. This project proposes to implement an educative game that teaches medical students how to carry out a neurological examination. The purpose is to improve not only the cognitive knowledge of the young physicians but also their sensorimotor skills. The game takes place in a virtual doctor office, which is modelled in 3D. Many possible clinical cases related to different neurologic diseases are simulated. The users are tested at two skill levels. First of all, they have to choose the right exam according to the patient’s symptoms. This initial stage is used to assess the theoretical expertise of the students. If the choice is correct, the physical examination begins. In order to evaluate the motor performance, a Kinect NUI is used. Such a device allows for the natural and intuitive control of the doctor’s avatar because there is a direct link between the individual’s and the avatar’s joints. Due to the fact that the real movements of the student are recorded with some accuracy, it is possible to gauge whether or not the medical gesture is properly applied to the virtual patient. In particular, the force and the precision of the movements are measured and compared to reference values. After each examination immediate feedback is given, so that the learners may rectify their choices and improve the quality of their motor skills at the next training session. Overall, the objective of this software is to enable the future physicians to practice a basic medical exam on a wide scope of neurologic disorders, without any risk for the patients and through an enjoyable approach.

Ghisolfi, A., C. Fliedel, V. Rosa, R. Pattacini, A. Thibon, K. Yu. Monakhov, and P. Braunstein. "Solvent-dependent reversible ligand exchange in nickel complexes of a monosulfide bis(diphenylphosphino)(N-thioether)amine." Chemistry - An Asian Journal. 8.8 (2013): 1795-1805. AbstractWebsite
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