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2013
Figueiredo, Angelo Miguel, João Sardinha, Geoffrey R. Moore, and Eurico J. Cabrita. "Protein destabilisation in ionic liquids: the role of preferential interactions in denaturation." Phys. Chem. Chem. Phys..15 (2013): 19632-19643. AbstractWebsite

The preferential binding of anions and cations in aqueous solutions of the ionic liquids (ILs) 1-butyl- 3-methylimidazolium ([C4mim]+) and 1-ethyl-3-methylimidazolium ([C2mim]+) chloride and dicyanamide (dca-) with the small alpha-helical protein Im7 was investigated using a combination of differential scanning calorimetry, NMR spectroscopy and molecular dynamics (MD) simulations. Our results show that direct ion interactions are crucial to understand the effects of ILs on the stability of proteins and that an anion effect is dominant. We show that the binding of weakly hydrated anions to positively charged or polar residues leads to the partial dehydration of the backbone groups, and is critical to control stability, explaining why dca- is more denaturing than Cl-. Direct cation–protein interactions also mediate stability; cation size and hydrophobicity are relevant to account for destabilisation as shown by the effect of [C4mim]+ compared to [C2mim]+. The specificity in the interaction of IL ions with protein residues established by weak favourable interactions is confirmed by NMR chemical shift perturbation, amide hydrogen exchange data and MD simulations. Differences in specificity are due to the balance of interaction established between ion pairs and ion-solvent that determine the type of residues affected. When the interaction of both cation and anion with the protein is strong the net result is similar to a non-specific interaction, leading ultimately to unfolding. Since the nature of the ions is a determinant of the level of interaction with the protein towards denaturation or stabilisation, ILs offer a unique possibility to modulate protein stabilisation or even folding events.

Karlovich, Alexei Yu., and Ilya M. Spitkovsky. "Pseudodifferential operators on variable Lebesgue spaces." Operator Theory, Pseudo-Differential Equations, and Mathematical Physics. Operator Theory: Advances and Applications, 228. Eds. Yuri I. Karlovich, Luigi Rodino, Bernd Silbermann, and Ilya M. Spitkovsky. Basel: Birkhäuser, 2013. 173-183. Abstract

Let \(\mathcal{M}(\mathbb{R}^n)\) be the class of bounded away from one and infinity functions \(p:\mathbb{R}^n\to[1,\infty]\) such that the Hardy-Littlewood maximal operator is bounded on the variable Lebesgue space \(L^{p(\cdot)}(\mathbb{R}^n)\). We show that if \(a\) belongs to the Hörmander class \(S_{\rho,\delta}^{n(\rho-1)}\) with \(0<\rho\le 1\), \(0\le\delta<1\), then the pseudodifferential operator \(\operatorname{Op}(a)\) is bounded on the variable Lebesgue space \(L^{p(\cdot)}(\mathbb{R}^n)\) provided that \(p\in\mathcal{M}(\mathbb{R}^n)\). Let \(\mathcal{M}^*(\mathbb{R}^n)\) be the class of variable exponents \(p\in\mathcal{M}(\mathbb{R}^n)\) represented as \(1/p(x)=\theta/p_0+(1-\theta)/p_1(x)\) where \(p_0\in(1,\infty)\), \(\theta\in(0,1)\), and \(p_1\in\mathcal{M}(\mathbb{R}^n)\). We prove that if \(a\in S_{1,0}^0\) slowly oscillates at infinity in the first variable, then the condition \[ \lim_{R\to\infty}\inf_{|x|+|\xi|\ge R}|a(x,\xi)|>0 \] is sufficient for the Fredholmness of \(\operatorname{Op}(a)\) on \(L^{p(\cdot)}(\mathbb{R}^n)\) whenever \(p\in\mathcal{M}^*(\mathbb{R}^n)\). Both theorems generalize pioneering results by Rabinovich and Samko [RS08] obtained for globally log-Hölder continuous exponents \(p\), constituting a proper subset of \(\mathcal{M}^*(\mathbb{R}^n)\).

Micael Inácio, António Ramos, Válter Lúcio, and Duarte Faria. "Punching of High Strength Concrete Flat Slabs - Experimental Investigation." fib symposium Tel Aviv 2013. Tel Aviv: fib, 2013. 377-380. Abstract

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Gouveia, Nuno, Nelson Fernandes, Duarte Faria, António Ramos, and Válter Lúcio. "Punching of Steel Fibre Reinforced Concrete Flat Slabs." fib symposium Tel Aviv 2013. Ed. Fib. Tel Aviv: IACIE, 2013. 1-4. Abstract

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Ramos, A., Lúcio Faria Almeida Fernandes Inácio Mamede Dinarte Silva V. D. A. "Punçoamento em Estruturas de Betão Armado." 2º Congresso Internacional da Habitação no Espaço Lusofono. Ed. FFCT. Lisbon 2013. 2013. Abstract

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Gouveia, N. D., D. M. V. Faria, and A. M. P. Ramos. "Punçoamento em lajes de betão com fibras de aço." Revista Internacional TECH ITT by Construlink. 11 (2013). Abstract

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D. Algarvio, Maria Margarida Rolim Augusto Lima, Cunha M. L. "Quality Improvement of Recycled Aggregates from a Construction and Demolition Waste Recycling Pilot Plant." Advanced Materials Forum Vi. 730-732 (2013): 630-635 .
Cunha, Jácome, João Paulo Fernandes, Jorge Mendes, Rui Pereira, and João Saraiva. "Querying Model-Driven Spreadsheets." Proceedings of the 2013 IEEE Symposium on Visual Languages and Human-Centric Computing. VLHCC '13. Washington, DC, USA: IEEE Computer Society, 2013. 83-86. Abstractvlhcc2013-query.pdf

Spreadsheets are being used with many different purposes that range from toy applications to complete information systems. In any of these cases, they are often used as data repositories that can grow significantly. As the amount of data grows, it also becomes more difficult to extract concrete information out of them. This paper focuses on the problem of spreadsheet querying. In particular, we propose an expressive and composable technique where intuitive queries can be defined. Our approach builds on a model-driven spreadsheet development environment, and queries are expressed referencing entities in the model of a spreadsheet instead of in its actual data. Finally, the system that we have implemented relies on Google's query function for spreadsheets.

Belo, Orlando, Jácome Cunha, João Paulo Fernandes, Jorge Mendes, Rui Pereira, and João Saraiva. "QuerySheet: A Bidirectional Query Environment for Model-Driven Spreadsheets." Proceedings of the 2013 IEEE Symposium on Visual Languages and Human-Centric Computing. VLHCC '13. Washington, DC, USA: IEEE Computer Society, 2013. 199-200. Abstractvlhcc2013-td.pdf

This paper presents a tool, named QUERYSHEET, to query spreadsheets. We defined a language to write the queries, which resembles SQL, the language to query databases. This allows to write queries which are more related to the spreadsheet content than with current approaches.

Liu, H., Â. Mestre, and Teresa Sousa. "Rainbow vertex k-connection in graphs." Discrete Applied Mathematics. 161.16-17 (2013): 2549-2555. Abstractrvck-preprint.pdf

Let k be a positive integer and G be a k-connected graph. An edge-coloured path is rainbow if its edges have distinct colours. The rainbow k-connection number of G, denoted by rc_k(G), is the minimum number of colours required to colour the edges of G so that any two vertices of G are connected by k internally vertex-disjoint rainbow paths. The function rc_k(G) was first introduced by Chartrand, Johns, McKeon, and Zhang in 2009, and has since attracted considerable interest. In this paper, we consider a version of the function rc_k(G) which involves vertex-colourings. A vertex-coloured path is vertex-rainbow if its internal vertices have distinct colours. The rainbow vertex k-connection number of G, denoted by rvc_k(G), is the minimum number of colours required to colour the vertices of G so that any two vertices of G are connected by k internally vertex-disjoint vertex-rainbow paths. We shall study the function rvc_k(G) when G is a cycle, a wheel, and a complete multipartite graph. We also construct graphs G where rc_k(G) is much larger than rvc_k(G) and vice versa so that we cannot in general bound one of rc_k(G) and rvc_k(G) in terms of the other.

Maiti, Biplab K., Teresa Avilés, Marta S. P. Carepo, Isabel Moura, Sofia R. Pauleta, and José J. G. Moura. "Rearrangement of Mo-Cu-S Cluster Reflects the Structural Instability of Orange Protein Cofactor." Z. Anorg. Allg. Chem.. 639.8-9 (2013): 1361-1364.
Delgado, Manuel, and Vítor H. Fernandes. "Rees quotients of numerical semigroups." Portugaliae Mathematica. 70.2 (2013): 93-112. AbstractWebsite

We introduce a class of finite semigroups obtained by considering Rees
quotients of numerical semigroups.
Several natural questions concerning this class, as well as particular
subclasses obtained by considering some special ideals, are answered while
others remain open. We exhibit nice presentations for these semigroups and
prove that the Rees quotients by ideals of N, the positive integers under
addition, constitute a set of generators for the pseudovariety of commutative
and nilpotent semigroups.

M. Figueiredo, Evans G., and J. Goes. "A Reference-Free 7-bit 500 MS/s Pipeline ADC Using Current-Mode Reference Shifting and Built-in Threshold Quantizers." Analog Integrated Circuits and Signal Processing Journal (Springer). vol. 75.no. 1 (2013): pp. 53-65.
Amado, Miguel, P., H. Almeida, M. R. Ribeiro, and A. Gameiro Regeneration of the city through the rehabilitation process of built heritage. 2º Congresso Internacional da habitação no Espaço Lusófono. Lisboa, PT: LNEC, ISBN: 978-178-032-381-7, 2013.
Pava, J. A., C. Banquet, J. D. Silva, and F. Oliveira. "The Regularized Boussinesq equation: Instability of periodic traveling waves." Journal of Differential Equations. 254.9 (2013): 3994-4023.Website
Silva, João A., Tiago M. Vale, João M. Lourenço, and Hervé Paulino. "Replicação Parcial com Memória Transacional Distribuída." Proceedings of INForum Simpósio de Informática. INForum 2013. Lisbon, Portugal: Faculdade de Ciências e Tecnologia da Universidade Nova de Lisboa, 2013. 310-321. Abstractinforum13-silva.pdf

Os sistemas de memória transacional distribuída atuais recorrem essencialmente à distribuição ou à replicação total para distribuir os seus dados pelos múltiplos nós do sistema. No entanto, estas estratégias de replicação de dados apresentam limitações. A distribuição não oferece tolerância a falhas e a replicação total limita a capacidade de armazenamento do sistema. Nesse contexto, a replicação parcial de dados surge como uma solução intermédia, que combina o melhor das duas anteriores com o intuito de mitigar as suas desvantagens. Esta estratégia tem sido explorada no contexto das bases de dados distribuídas, mas tem sido pouco abordada no contexto da memória transacional e, tanto quanto sabemos, nunca antes tinha sido incorporada num sistema de memória transacional distribuída para uma linguagem de propósito geral. Assim, neste artigo propomos e avaliamos uma infraestrutura para replicação parcial de dados para programas Java bytecode, que foi desenvolvida com base num sistema já existente de memória transacional distribuída. A modularidade da infraestrutura que apresentamos permite a implementação de múltiplos algoritmos e, por conseguinte, avaliar em que contextos de utilização (workloads, número de nós, etc.) a replicação parcial se apresenta como uma alternativa viável a outras estratégias de replicação de dados.

Veiga, João, Rui Micaelo, and Adelino Ferreira Rutting models for the use in pavement maintenance management. 9th International Conference on the Bearing Capacity of Roads, Railways and Airfields. Trondheim, Norway, 2013.
Ramos, Luís P., João T. Mexia, and Pedro P. Mota. "Sample partitioning estimation for ergodic diffusions." Communications in Statistics - Simulation and Computation (2013).Website
and Amarante dos Santos, F. P. and Cismaşiu, Pamies Teixeira C. J. "Semi-active vibration control device based on superelastic NiTi wires." Structural Control and Health Monitoring. 20 (2013): 890-902.Website
Amarante dos Santos, F. P., C. Cismaşiu, and J. Pamies Teixeira. "Semi-active vibration control device based on superelastic NiTi wires." Structural Control and Health Monitoring. 20.6 (2013): 890-902. AbstractWebsite

The present paper presents a physical prototype that simulates the response of a single degree of freedom dynamic system, equipped with a novel semi-active vibration control device. This device comprises two superelastic NiTi elements working in phase opposition and aims to prevent deck unseating in simply supported bridges, during a seismic excitation. The special design of this device allows to avoid problems related to stress–relaxation phenomena and material degradation because of cyclic loading that have been observed in similar passive dissipation devices. The proposed design uses a strategy that permits the continuous adapting of the accumulated stress in the NiTi wires, on the basis of the response of the device to external excitations. Although unloaded, the NiTi elements remain strain/stress free, preventing stress–relaxation phenomena. With the occurrence of a dynamic excitation, a cumulative strain/stress process in the superelastic wires is initiated, enabling higher martensite transformation ratios and therefore increasing the damping capacities of the system while keeping the stresses in the wires inside a narrower superelastic window. The strain/stress accumulation in the superelastic wires is a direct result of the motion of the structure itself, with no need for external energy input.

Anjos, Miguel F., and Manuel V. C. Vieira. "Semidefinite Resolution and Exactness of Semidefinite Relaxations for Satisfiability." Discrete Applied Mathematics. 161.18 (2013): 2812-2826.
Carrasco, G., Rybarczyk Y., Cardoso T., and Martins I.P. "A serious game for multimodal training of physician novices." 6th International Conference of Education, Research and Innovation. Seville, Spain 2013. copy.pdfposter.pdf
Cismasiu, Corneliu, and Filipe 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.
authors, Several, and Editor: Braz F. M. Fernandes Shape Memory Alloys- Processing, Characterization and Applications. 51000 Rijeka, Croatia: InTech, 2013.