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2016
Lourenço, P., B. J. Guerreiro, P. Batista, P. Oliveira, and C. Silvestre. "{Simultaneous Localization and Mapping for Aerial Vehicles: a 3-D sensor-based GAS filter}." Autonomous Robots. 40 (2016): 881-902. Abstract
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2015
Bahubalindruni, Pydi Ganga, Vitor Grade Tavares, Pedro Barquinha, Candido Duarte, Nuno Cardoso, Pedro Guedes de Oliveira, Rodrigo Martins, and Elvira Fortunato. "a-GIZO TFT neural modeling, circuit simulation and validation." Solid-State Electronics. 105 (2015): 30-36. AbstractWebsite
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Morais, Ana Rita C., Joana Vaz Pinto, Daniela Nunes, Luísa B. Roseiro, Maria Conceição Oliveira, Elvira Fortunato, and Rafał Bogel-Łukasik. "{Imidazole: Prospect Solvent for Lignocellulosic Biomass Fractionation and Delignification}." ACS Sustainable Chemistry {&} Engineering (2015). AbstractWebsite
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Amado, Miguel P., A. Reaes Pinto, Ana M. Oliveira, and I. Ramalhete "Construção Sustentável - conceito e prática". Casal de Cambra, Lisboa: Editora Caleidoscópio_Edição e Artes Gráficas, SA, Casal de Cambra, ISBN: 978-989-658-324-8, 2015.
Ghiassi, B., J. Xavier, D. V. Oliveira, A. Kwiecien, P. B. Lourenço, and B. Zajac. "Evaluation of the bond performance in FRP-brick components re-bonded after initial delamination." Composite Structures. 123 (2015): 271-281. Abstract

Abstract The bond behavior between Fiber Reinforced Polymers (FRPs) and masonry substrates has been the subject of many studies during the last years. Recent accelerated aging tests have shown that bond degradation and \{FRP\} delamination are likely to occur in FRP-strengthened masonry components under hygrothermal conditions. While an investigation on the possible methods to improve the durability of these systems is necessary, the applicability of different bond repair methods should also be studied. This paper aims at investigating the debonding mechanisms after repairing delaminated FRP-strengthened masonry components. FRP-strengthened brick specimens, after being delaminated, are repaired with two different adhesives: a conventional epoxy resin and a highly flexible polymer. The latter is used as an innovative adhesive in structural applications. The bond behavior in the repaired specimens is investigated by performing single-lap shear bond tests. Digital image correlation (DIC) is used for deeper investigation of the surface deformation and strains development. The effectiveness of the repair methods is discussed and compared with the strengthened specimens.

Abdollahvand, S., L. Oliveira, L. Gomes, and J. Goes A low-voltage voltage-controlled ring-oscillator employing dynamic-threshold-MOS and body-biasing techniques. IEEE International Symposium on Circuits and Systems (ISCAS’15). Lisbon, Portugal: IEEE, 2015.
H., Liu, Pikhurko O., and Sousa Teresa. "Monochromatic Clique Decompositions of Graphs." Journal of Graph Theory. 80 (2015): 287-298. Abstractgeneral-mono-clique.pdf

Let $G$ be a graph whose edges are coloured with $k$ colours, and $\mathcal H=(H_1,\dots , H_k)$ be a $k$-tuple of graphs. A \emph{monochromatic $\mathcal H$-decomposition} of $G$ is a partition of the edge set of $G$ such that each part is either a single edge or forms a monochromatic copy of $H_i$ in colour $i$, for some $1\le i\le k$. Let $\phi_{k}(n,\mathcal H)$ be the smallest number $\phi$, such that, for every
order-$n$ graph and every $k$-edge-colouring, there is a monochromatic $\mathcal H$-decomposition with at most $\phi$ elements. Extending the previous results of Liu and Sousa [``Monochromatic $K_r$-decompositions of graphs", \emph{Journal of Graph Theory}76:89-100,2014], we solve this problem
when each graph in $\mathcal H$ is a clique and $n\ge n_0(\mathcal H)$ is sufficiently large.

Brandao Moniz, António, Go Yoshizawa, and Michiel Van Oudheusden. "Technology Assessment in East Asia: Experience and New Approaches." The Next Horizon of Technology Assessment. Prague: Technology Centre ASCR, 2015. 287-293. Abstract

Technology assessment (TA) and TA-like activities in countries like Japan have a unique history and continue to play a role in contemporary science, technology, and innovation (STI) processes. The aim of the discussion of TA’s experience in East Asia is how STI governance is locally enacted in Asian knowledge-driven economies, as TA activities develop in conjunction with STI policies and programs. To render these processes, policies, and programs visible and to understand their implications for STI governance, a panel at the Berlin conference on TA discussed contributions that described and conceptualized, for example, how TA activities have emerged in Asian knowledge-based economies (KBE), in which particular forms (e.g., academic and parliamentary TA programs), to which technologies and/or actors they are linked, and which methods are used and why. The panel also sought to compare and contrast how TA is (or is not) institutionalized in Asian countries and regions, and to point to prospects for expansion of TA capacity. In doing so, the panellists placed the development of TA in a historical, sociological, and comparative perspective, and opened space for critical reflection on the potential, problems, and limitations associated with initiating TA in Asia and with KBEs overall

Xavier, J., M. Oliveira, J. J. L. Morais, and M. F. S. F. de Moura. "Determining mode I cohesive law of Pinus pinaster by coupling double cantilever beam test with digital image correlation." Fracture and Structural Integrity. 31 (2015): 13-22. AbstractWebsite

The direct identification of the cohesive law in pure mode I of Pinus pinaster is addressed. The approach couples the double cantilever beam (DCB) test with digital image correlation (DIC). Wooden beam specimens loaded in the radial-longitudinal (RL) fracture propagation system are used. The strain energy release rate in mode I (GI ) is uniquely determined from the load-displacement ( P ?? ) curve by means of the compliance-based beam method (CBBM). This method relies on the concept of equivalent elastic crack length ( eq a ) and therefore does not require the monitoring of crack propagation during test. The crack tip opening displacement in mode I ? ? I w is determined from the displacement field at the initial crack tip. The cohesive law in mode I I I (? ? w ) is then identified by numerical differentiation of the I I G ? w relationship. Moreover, the proposed procedure is validated by finite element analyses including cohesive zone modelling. It is concluded that the proposed data reduction scheme is adequate for assessing the cohesive law in pure mode I of P. pinaster.

Conchinha, Cristina, Patrícia Osório, and João Correia de Freitas. "Playful learning: {Educational} robotics applied to students with learning disabilities." Setúbal 2015. Abstract

Since the ratification of the Salamanca agreement in 1994 that it is the concern of schools to seek inclusive approaches that may lead all students to academic success through differentiated strategies and adaptations or curricular and environmental

Bernacka-Wojcik, Iwona, Hugo Águas, Fabio Ferreira Carlos, Paulo Lopes, Pawel Jerzy Wojcik, Mafalda Nascimento Costa, Bruno Veigas, Rui Igreja, Elvira Fortunato, Pedro Viana Baptista, and others. "Single nucleotide polymorphism detection using gold nanoprobes and bio-microfluidic platform with embedded microlenses." Biotechnology and bioengineering. 112 (2015): 1210-1219. Abstract
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Soares, Paula I. P., Frederik Lochte, Coro Echeverria, Laura CJ Pereira, Joana T. Coutinho, Isabel M. M. Ferreira, Carlos M. M. Novo, and others. "Thermal and magnetic properties of iron oxide colloids: influence of surfactants." Nanotechnology. 26 (2015): 425704. Abstract
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Silva, Teresa Pereira, João Pedro Veiga, Daniel PS Oliveira, Maria João Batista, Diogo Rosa, and Ondina M. Figueiredo. "A utilização da radiação de sincrotrão no estudo de materiais geológicos; breve abordagem sobre experiências recentes de um grupo de utilizadores." Geonovas (2015). Abstract
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Figueiredo, Ondina M., Teresa Pereira Silva, João Pedro Veiga, Maria João Batista, and Daniel PS Oliveira. "X-ray absorption near-edge spectroscopy (XANES) applied to the speciation of tungsten in Panasqueira mine debris." 4th ENURS and ESRF-Day Meeting of Synchrotron Radiation Users from Portugal. 2015. Abstract
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Barros, A. A., C. Oliveira, R. L. Reis, E. Lima, and A. R. C. Duarte. "{Ketoprofen-eluting biodegradable ureteral stents by CO{\textless}inf{\textgreater}2{\textless}/inf{\textgreater}impregnation: In vitro study}." International Journal of Pharmaceutics. 495 (2015). Abstract

© 2015 Elsevier B.V. Ureteral stents are indispensable tools in urologic practice. The main complications associated with ureteral stents are dislocation, infection, pain and encrustation. Biodegradable ureteral stents are one of the most attractive designs with the potential to eliminate several complications associated with the stenting procedure. In this work we hypothesize the impregnation of ketoprofen, by CO 2 -impregnation in a patented biodegradable ureteral stent previously developed in our group. The biodegradable ureteral stents with each formulation: alginate-based, gellan gum-based were impregnated with ketoprofen and the impregnation conditions tested were 100 bar, 2 h and three different temperatures (35 °C, 40°C and 50°C). The impregnation was confirmed by FTIR and DSC demonstrated the amorphization of the drug upon impregnation. The in vitro elution profile in artificial urine solution (AUS) during degradation of a biodegradable ureteral stent loaded with ketoprofen was evaluated. According to the kinetics results these systems have shown to be very promising for the release ketoprofen in the first 72 h, which is the necessary time for anti-inflammatory delivery after the surgical procedure. The in vitro release studied revealed an influence of the temperature on the impregnation yield, with a higher impregnation yield at 40°C. Higher yields were also obtained for gellan gum-based stents. The non-cytotoxicity characteristic of the developed ketoprofen-eluting biodegradable ureteral stents was evaluated in L929 cell line by MTS assay which demonstrated the feasibility of this product as a medical device.

2014
Gaspar, D., S. N. Fernandes, G. dea Oliveira, J. G. Fernandes, P. Grey, R. V. Pontes, L. Pereira, R. Martins, M. H. Godinho, and E. Fortunato. "{Nanocrystalline cellulose applied simultaneously as the gate dielectric and the substrate in flexible field effect transistors.}." Nanotechnology. 25 (2014): 094008. AbstractWebsite

Cotton-based nanocrystalline cellulose (NCC), also known as nanopaper, one of the major sources of renewable materials, is a promising substrate and component for producing low cost fully recyclable flexible paper electronic devices and systems due to its properties (lightweight, stiffness, non-toxicity, transparency, low thermal expansion, gas impermeability and improved mechanical properties).Here, we have demonstrated for the first time a thin transparent nanopaper-based field effect transistor (FET) where NCC is simultaneously used as the substrate and as the gate dielectric layer in an 'interstrate' structure, since the device is built on both sides of the NCC films; while the active channel layer is based on oxide amorphous semiconductors, the gate electrode is based on a transparent conductive oxide.Such hybrid FETs present excellent operating characteristics such as high channel saturation mobility (>7 cm(2) V (-1) s(-1)), drain-source current on/off modulation ratio higher than 10(5), enhancement n-type operation and subthreshold gate voltage swing of 2.11 V/decade. The NCC film FET characteristics have been measured in air ambient conditions and present good stability, after two weeks of being processed, without any type of encapsulation or passivation layer. The results obtained are comparable to ones produced for conventional cellulose paper, marking this out as a promising approach for attaining high-performance disposable electronics such as paper displays, smart labels, smart packaging, RFID (radio-frequency identification) and point-of-care systems for self-analysis in bioscience applications, among others.

Orosa, Lois, and João M. Lourenço. "Hardware Approach for Detecting, Exposing and Tolerating High Level Atomicity Violations." Proceedings of Joint Euro-TM/MEDIAN Workshop on Dependable Multicore and Transactional Memory Systems. DMTM 2014. Vienna, Austria 2014. Abstractdmtm-2014-lorosa.pdf

In this paper we address a solution for detecting and tolerating one of the most typical concurrency bugs: atomicity violations. More specifically, we address High-Level Atomicity Violations (HLAV). High-level atomicity violations result from the misspecification of the scope of an atomic block, by splitting it in two or more atomic blocks which may be interleaved with other atomic blocks. Figure 1 shows an example of this type of atomicity violation. The intuitive idea behind HLAV is that if two shared data items (e.g., memory locations) were both accessed inside an atomic block, they are interrelated and probably the programmer intention is that there shall be no interleavings between these two accesses. Therefore, if (in the same program) this two addresses are accessed separately in different atomic blocks, an unfortunate interleaving may cause an atomicity violation.

Bernardo, Vasco, André Oliveira, Filipe Amarante dos Santos, and Corneliu Cismasiu. "Vulnerabilidade e reforço sísmico de uma passagem superior pedonal pré-fabricada." 5as Jornadas Portuguesas de Engenharia de Estruturas. Lisboa, Portugal : LNEC, 2014.
Figueiredo, Maria-Ondina, Teresa P. Silva, Joao P. Veiga, Maria-Joao Batista, Eduardo Salas-Colera, and Daniel P. de Oliveira. "Selenium Speciation in Waste Materials From an Exhausted Iberian Pyrite Belt Mine." Journal of Materials Science Research. 3.4 (2014): p22. Abstract

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Ferrás, L., N. Ford, L. Morgado, and M. Rebelo. "A numerical method for the solution of the time-fractional diffusion equation." Computational Science and Its Applications – ICCSA 2014. Eds. B. M. Torre, S. Misra, A. M. A. C. Rocha, C. Torre, J. G. Rocha, M. I. Falcão, D. Taniar, B. Apduhan, and O.Gervasi. Switzerland: Springer International Publishing, 2014. 117-131.
Otelo-Cardoso, AR, V. Schwuchow, D. Rodrigues, E. J. Cabrita, S. Leimkühler, MJ Romão, and T. Santos-Silva. "Biochemical, Stabilization and Crystallization Studies on a Molecular Chaperone (PaoD) Involved in the Maturation of Molybdoenzymes." PLoS One. 9 (2014): e87295 . AbstractWebsite

Molybdenum and tungsten enzymes require specific chaperones for folding and cofactor insertion. PaoD is the chaperone of the periplasmic aldehyde oxidoreductase PaoABC. It is the last gene in the paoABCD operon in Escherichia coli and its presence is crucial for obtaining mature enzyme. PaoD is an unstable, 35 kDa, protein. Our biochemical studies showed that it is a dimer in solution with a tendency to form large aggregates, especially after freezing/thawing cycles. In order to improve stability, PaoD was thawed in the presence of two ionic liquids [C4mim]Cl and [C2OHmim]PF6 and no protein precipitation was observed. This allowed protein concentration and crystallization using polyethylene glycol or ammonium sulfate as precipitating agents. Saturation transfer difference – nuclear magnetic resonance (STD-NMR) experiments have also been performed in order to investigate the effect of the ionic liquids in the stabilization process, showing a clear interaction between the acidic ring protons of the cation and, most likely, negatively charged residues at the protein surface. DLS assays also show a reduction of the overall size of the protein aggregates in presence of ionic liquids. Furthermore, cofactor binding studies on PaoD showed that the protein is able to discriminate between molybdenum and tungsten bound to the molybdenum cofactor, since only a Mo-MPT form of the cofactor remained bound to PaoD.

Coelho, T., De Oliveira, R., Cardoso, T., Rosas, J., and Rybarczyk Y. "Body ownership of virtual avatars: an affordance approach of telepresence." Innovative and Creative Developments in Multimodal Interaction Systems. Eds. Y. Rybarczyk, T. Cardoso, J. Rosas, and L. Camarinha-Matos. Heidelberg: Springer, 2014. 3-19.
Rybarczyk, Yves, Tiago Cardoso, Tiago Coelho, Rita Oliveira, and João Rosas. "Body Ownership of Virtual Avatars: An affordance Approach of Telepresence." Enterface 2013 Proceedings. Springer, 2014. Abstract

Virtual environments are an increasing trend in today’s society. In this scope, the avatar is the representation of the user in the virtual world. However, that relationship lacks empirical studies regarding the nature of the interaction between avatars and human beings. For that purpose it was studied how the avatar’s modeled morphology and dynamics affect its control by the user. An experiment was conducted to measure telepresence and ownership on participants who used a Kinect Natural User Interface (NUI). The body ownership of different avatars was assessed through a behavioral parameter, based on the concept of affordances, and a questionnaire of presence. The results show that the feelings of telepresence and ownership seem to be greater when the kinematics and the avatar’s proportions are closer to those of the user.

Carreiro-Martins, Pedro, João Viegas, Ana Luisa Papoila, Daniel Aelenei, Iolanda Caires, José Araújo-Martins, João Gaspar-Marques, Maria Manuela Cano, Ana Sofia Mendes, Daniel Virella, and others. "CO2 concentration in day care centres is related to wheezing in attending children." European journal of pediatrics. 173 (2014): 1041-1049.
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.