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2015
Kchaou, Omaya Bellaaj, Amin Sallem, Pedro Pereira, Mourad Fakhfakh, and Maria Helena Fino Multi-objective sensitivity-based optimization of analog circuits exploiting NSGA-II front ranking. Synthesis, Modeling, Analysis and Simulation Methods and Applications to Circuit Design (SMACD). Istambul, Turkey: IEEE, 2015.
Poggi, Francesca, Ana Firmino, Miguel Amado, and Fernando Pinho. "Natural stone walls in vernacular architecture: what contribution towards Rural nZEB concept?" Bulletin de la Société Géographique de Liège. 51-66. 65.ISSN 0770-7576. 65:2 (2015).
Biscaia, Hugo C., Carlos Chastre, André Viegas, and Noel Franco. "Numerical modelling of the effects of elevated service temperatures on the debonding process of frp-to-concrete bonded joints." Composites Part B: Engineering. 70 (2015): 64-79. AbstractWebsite

There are many issues concerning the performance behaviour of FRP-to-concrete interfaces at elevated service temperatures (EST). At EST, i.e. slightly above the glass transition temperature (Tg), some properties associated with the FRP composites, such as the stiffness, strength or the bond characteristics, degrade. This is a crucial issue and there are only a few studies that take into account such effects on FRP-to-concrete interfaces at EST. This paper examines, through a numerical analysis, the performance of FRP-to-concrete bonded joints at EST using a new discrete model based on truss elements and shear springs. The External Bonded Reinforcement (EBR) systems subjected to EST are analyzed. The numerical discrete model was implemented in a MATLAB routine and the bond-slip curves of the interfaces at EST were obtained from a model found in literature. The numerical results revealed that the interface at EST behaves similarly to one with two equal mechanical loads applied at both ends of the FRP plate. The load-slip curves or bond stresses, strains or slippages along the bonded length obtained from several bond-slip curves at different temperatures were obtained. Two different single-lap shear tests were simulated at steady-state (steady temperature followed by load increase) and transient state (steady load followed by temperature increase). Regarding the influence of the temperature on the adhesion between the FRP and concrete, the results showed that an increase in the temperature at an earlier situation, i.e. during a period where temperature had no influence in the concrete deformations, leads to an increase in the effective bond length of the interface affecting the initial strength of the interface.

Brás, C. P., M. Fukushima, A. N. Iusem, and J. J. Júdice. "On the Quadratic Eigenvalue Complementarity Problem over a General Convex Cone." Applied Mathematics and Computation. 271 (2015): 594-608. AbstractWebsite

The solution of the Conic Quadratic Eigenvalue Complementarity Problem (CQEiCP) is first investigated without assuming symmetry on the matrices defining the problem. A new sufficient condition for existence of solutions of CQEiCP is presented, extending to arbitrary pointed, closed and convex cones a condition known to hold when the cone is the nonnegative orthant. We also address the symmetric CQEiCP where all its defining matrices are symmetric. We show that, assuming that two of its defining matrices are positive definite, this symmetric CQEiCP reduces to the computation of a stationary point of an appropriate merit function on a convex set. Furthermore, we discuss the use of the so called Spectral Projected Gradient (SPG) algorithm for solving CQEiCP when the cone of interest is the second-order cone (SOCQEiCP). A new algorithm is designed for the computation of the projections required by the SPG method to deal with SOCQEiCP. Numerical results are included to illustrate the efficiency of the SPG method and the new projection technique in practice.

Pereira, P., F. Passos, and M. H. Fino. "Optimization-Based Design of RF-VCOs with Tapered Inductors." Performance Optimization Techniques in Analog, Mixed-Signal, and Radio-Frequency Circuit Design. Eds. M. FahkFahk, E. Tlelo-Cuautle, and M. H. Fino. IGI Global, 2015.
Cicalò, Serena, Vítor H. Fernandes, and Csaba Schneider. "Partial transformation monoids preserving a uniform partition." Semigroup Forum (DOI 10.1007/s00233-014-9629-5). 90.2 (2015): 532-544. AbstractWebsite

The objective of this paper is to study the monoid of all partial
transformations of a finite set that preserve a uniform partition. In addition
to proving that this monoid is a quotient of a wreath product with respect to a
congruence relation, we show that it is generated by 5 generators, we compute
its order and determine a presentation on a minimal generating set.

Passos, Fabio, Mouna Kotti, R. Gonzalez-Echevarria, M. H. Fino, E. Roca, R. Castro-Lopez, and F. V. Fernandez Physical vs. Surrogate Models of Passive RF Devices. 2015 IEEE International Symposium on Circuits and Systems. Lisbon: IEEE, 2015.
Cavique, Miguel, João Flores, Miguel Amado, António Gonçalves-Coelho, and António Mourão. "A preliminary check of the refurbishing large office buildings to a zero energy condition." CIRP. 1.34 (2015): 193-198.
Sousa, D. G., R. J. Dias, C. Ferreira, and J. M. Lourenço. "Preventing Atomicity Violations with Contracts." ArXiv e-prints (2015). Abstract1505.02951v1-dsousa.pdfWebsite

Software developers are expected to protect concurrent accesses to shared regions of memory with some mutual exclusion primitive that ensures atomicity properties to a sequence of program statements. This approach prevents data races but may fail to provide all necessary correctness properties.The composition of correlated atomic operations without further synchronization may cause atomicity violations. Atomic violations may be avoided by grouping the correlated atomic regions in a single larger atomic scope. Concurrent programs are particularly prone to atomicity violations when they use services provided by third party packages or modules, since the programmer may fail to identify which services are correlated. In this paper we propose to use contracts for concurrency, where the developer of a module writes a set of contract terms that specify which methods are correlated and must be executed in the same atomic scope. These contracts are then used to verify the correctness of the main program with respect to the usage of the module(s). If a contract is well defined and complete, and the main program respects it, then the program is safe from atomicity violations with respect to that module. We also propose a static analysis based methodology to verify contracts for concurrency that we applied to some real-world software packages. The bug we found in Tomcat 6.0 was immediately acknowledged and corrected by its development team.

Zhao, Ping, and Vítor H. Fernandes. "The ranks of ideals in various transformation monoids." Communications in Algebra (DOI:10.1080/00927872.2013.847946) . 43.2 (2015): 674-692. Abstractauthorsfinalversion.pdfWebsite

In this paper we consider various classes of monoids of transformations of a finite chain,
including those of transformations that preserve or reverse either the order or the orientation.
In line with Howie and McFadden (1990),
we complete the study of the ranks (and of idempotent ranks, when applicable) of all their ideals.

Faísca Phillips, Ana Maria, Fátima Nogueira, Fernanda Murtinheira, and Maria Teresa Barros. "Synthesis and antimalarial evaluation of novel fosmidomycin analogues." Bioorg. Med. Chem. Lett., http//dx.doi.org/10.1016/j.bmcl.2015.03.077. (2015).
Carvalho, L. C. R., D. Ribeiro, R. S. G. R. Seixas, A. M. S. Silva, M. Nave, A. C. Martins, S. Erhardt, E. Fernandes, E. J. Cabrita, and M. M. B. Marques. "Synthesis and evaluation of new benzimidazole-based COX inhibitors: a naproxen-like interaction detected by STD-NMR." RSC Advances. 5 (2015): 49098-49109. AbstractWebsite

Non-steroidal anti-inflammatory drugs exert their pharmacological activity through inhibition of cyclooxygenase 1 and 2 (COX-1 and COX-2). Recent research suggests that a balanced inhibition of both COX-1 and COX-2 is the key to reduce the side-effects exhibited by COX inhibitors. We developed new benzimidazole-based compounds that showed a balanced COX inhibition, supported by molecular docking screening. The human whole blood assays demonstrated that the ester derivatives were potent inhibitors. Competitive saturation transfer difference (STD)-NMR experiments, in the presence of COX-2, using naproxen and diclofenac demonstrated that ester derivatives do not compete with diclofenac for the same binding site, but compete with the allosteric inhibitor naproxen. Combination of NMR spectroscopy with molecular docking has permitted us to detect a new naproxen-like inhibitor, which could be used for future drug development.

Clemmensen, Lars B., Jesper Milàn, Jan Schulz Adolfssen, Eliza Jarl Estrup, Nicolai Frobøse, Nicole Klein, Octávio Mateus, and Oliver Wings. "The vertebrate-bearing Late Triassic Fleming Fjord Formation of central East Greenland revisited: stratigraphy, palaeoclimate and new palaeontological data." Geological Society, London, Special Publications. 434.1 (2015): 31-47. Abstractclemmensenetal2015greenland.pdfWebsite

In Late Triassic (Norian–Rhaetian) times, the Jameson Land Basin lay at 40° N on the northern part of the supercontinent Pangaea. This position placed the basin in a transition zone between the relatively dry interior of the supercontinent and its more humid periphery. Sedimentation in the Jameson Land Basin took place in a lake–mudflat system and was controlled by orbitally forced variations in precipitation. Vertebrate fossils have consistently been found in these lake deposits (Fleming Fjord Formation), and include fishes, dinosaurs, amphibians, turtles, aetosaurs and pterosaurs. Furthermore, the fauna includes mammaliaform teeth and skeletal material. New vertebrate fossils were found during a joint vertebrate palaeontological and sedimentological expedition to Jameson Land in 2012. These new finds include phytosaurs, a second stem testudinatan specimen and new material of sauropodomorph dinosaurs, including osteologically immature individuals. Phytosaurs are a group of predators common in the Late Triassic, but previously unreported from Greenland. The finding includes well-preserved partial skeletons that show the occurrence of four individuals of three size classes. The new finds support a late Norian–early Rhaetian age for the Fleming Fjord Formation, and add new information on the palaeogeographical and palaeolatitudinal distribution of Late Triassic faunal provinces.

Fliedel, Christophe, Vitor Rosa, Filipa M. Alves, Ana. M. Martins, Teresa Aviles, and Samuel Dagorne. "{P,O-Phosphinophenolate zinc(II) species: synthesis, structure and use in the ring-opening polymerization (ROP) of lactide, epsilon-caprolactone and trimethylene carbonate}." {DALTON TRANSACTIONS}. {44} (2015): {12376-12387}. Abstract

{The P, O-type phosphinophenol proligands (1 center dot H, 2-PPh2-4-Me-6-Me-C6H2OH; 2 center dot H, 2-PPh2-4-Me-6-Bu-t-C6H2OH) readily react with one equiv. of ZnEt2 to afford in high yields the corresponding Zn(II)ethyl dimers of the type {[}(kappa(2)-P, O) Zn-Et](2) (3 and 4) with two mu-O-Ph bridging oxygens connecting the two Zn(II) centers, as determined by X-ray diffraction (XRD) studies in the case of 3. Based on diffusion-ordered NMR spectroscopy (DOSY), both species 3 and 4 retain their dimeric structures in solution. The alcoholysis reaction of Zn(II) alkyls 3 and 4 with BnOH led to the high yield formation of the corresponding Zn(II) benzyloxide species {[}(kappa(2)-P, O) Zn-OBn](2) (5 and 6), isolated in a pure form as colorless solids. The centrosymmetric and dimeric nature of Zn(II) alkoxides 5 and 6 in solution was deduced from DOSY NMR experiments and multinuclear NMR data. Though the heteroleptic species 5 is stable in solution, its analogue 6 is instable in CH2Cl2 solution at room temperature to slowly decompose to the corresponding homoleptic species 8 via the transient formation of (kappa(2)-P, O)(2)Zn-2(mu-OBn)(mu-kappa(1):kappa(1)-P, O) (6'). Crystallization of compound 6 led to crystals of 6', as established by XRD analysis. The reaction of ZnEt2 with two equiv. of 1 center dot H and 2 center dot H allowed access to the corresponding homoleptic species of the type {[}Zn(P, O)(2)] (7 and 8). All gathered data are consistent with compound 7 being a dinuclear species in the solid state and in solution. Data for species 8, which bears a sterically demanding P, O-ligand, are consistent with a mononuclear species in solution. The Zn(II) alkoxide species 5 and the {[}Zn(P, O)(2)]-type compounds 7 and 8 were evaluated as initiators of the ring-opening polymerization (ROP) of lactide (LA), epsilon-caprolactone (epsilon-CL) and trimethylene carbonate (TMC). Species 5 is a well-behaved ROP initiator for the homo-, co- and terpolymerization of all three monomers with the production of narrow disperse materials under living and immortal conditions. Though species 7 and 8 are ROP inactive on their own, they readily polymerize LA in the presence of a nucleophile such as BnOH to produce narrow disperse PLA, presumably via an activated-monomer ROP mechanism.}

Kauf, Thomas, Vitor Rosa, Christophe Fliedel, Roberto Pattacini, Naina Deibel, Teresa Aviles, Biprajit Sarkar, and Pierre Braunstein. "{Reactivity of TCNE and TCNQ derivatives of quinonoid zwitterions with Cu(I)}." {DALTON TRANSACTIONS}. {44} (2015): {5441-5450}. Abstract

{The reactions of TCNE- and TCNQ-functionalized (TCNE: tetracyanoethylene and TCNQ: 7,7', 8,8'-tetra-cyanoquinodimethane) zwitterionic benzoquinonemonoimines with a Cu(I)-BIAN complex (BIAN = bis-(o, o'-bisisopropylphenyl)acenaphthenequinonediimine) have been investigated and found to follow a diversity of interesting patterns. The complexes {[}Cu(BIAN)(NCMe)(L2)]BF4 (2) and {[}Cu(BIAN)(L2)(2)]BF4 (4) were obtained by reacting {[}Cu(BIAN)(NCMe) 2] BF4 (1) with one and two equivalents of L2, respectively. Following similar procedures, the complexes {[}Cu(BIAN)(NCMe)(L3)] BF4 (6) and {[}Cu(BIAN)(L3)(2)]BF4 (7) were obtained by reaction of 1 with L3. The reaction of 2 with 0.5 equiv. of 4,4'-bipyridine afforded {[}\{Cu(BIAN)-(L2)\}(2)(mu-4,4'-bipyridine)](BF4)(2) (3). The complexes were characterized by multinuclear NMR, IR and UV-Vis spectroscopic techniques, mass spectrometry, cyclic voltammetry and elemental analysis. The molecular structures of complexes 3 center dot 4CH(2)Cl(2) and 4 center dot CH2Cl2 were determined by single crystal X-ray diffraction. An unexpected coordination polymer {[}Cu(L2(-))(2)](infinity) (5) was also structurally characterized, which contains Cu(II) centres chelated by two N, O-bound ligands resulting from the monodeprotonation of L2.}

Franco, José, Fátima Trindade, Sandra Silva, Miguel Palha, and Tiago Cardoso. "“No Reino dos Fonemas” jogo sério para a aprendizagem da leitura." (2015). Abstract

Neste artigo é apresentado um jogo sério que visa auxiliar a iniciação da aprendizagem do Princípio Alfabético
(discriminação auditiva dos sons das vogais) em crianças com dificuldades na aprendizagem (em particular
com alterações na consciência fonológica). Para isso são estudados vários motores de jogo e o conceito de elearning. São mostrados os vários cenários do jogo bem como as suas funcionalidades e propósitos. Este jogo
foi criado para capacitar instituições de apoio a crianças com perturbações do neurodesenvolvimento.

Young, M. T., S. Hua, L. Steel, D. Foffa, S. L. Brusatte, S. Thüring, O. Mateus, J. I. Ruiz-Omeñaca, P. Havlik, Y. Lepage, and M. B. De Andrade. "Addendum to ?Revision of the Late Jurassic teleosaurid genus Machimosaurus (Crocodylomorpha, Thalattosuchia)?" Royal Society Open Science. 2 (2015). Abstract
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Klein, Hendrik, Jesper Milàn, Lars B. Clemmensen, Nicolaj Frobøse, Octávio Mateus, Nicole Klein, Jan S. Adolfssen, Eliza J. Estrup, and Oliver Wings. "Archosaur footprints (cf. Brachychirotherium) with unusual morphology from the Upper Triassic Fleming Fjord Formation (Norian–Rhaetian) of East Greenland." Geological Society, London, Special Publications. 434 (2015). AbstractWebsite

The Ørsted Dal Member of the Upper Triassic Fleming Fjord Formation in East Greenland is well known for its rich vertebrate fauna, represented by numerous specimens of both body and ichnofossils. In particular, the footprints of theropod dinosaurs have been described. Recently, an international expedition discovered several slabs with 100 small chirotheriid pes and manus imprints (pes length 4–4.5 cm) in siliciclastic deposits of this unit. They show strong similarities with Brachychirotherium, a characteristic Upper Triassic ichnogenus with a global distribution. A peculiar feature in the Fleming Fjord specimens is the lack of a fifth digit, even in more deeply impressed imprints. Therefore, the specimens are assigned here tentatively to cf. Brachychirotherium. Possibly, this characteristic is related to the extremely small size and early ontogenetic stage of the trackmaker. The record from Greenland is the first evidence of this morphotype from the Fleming Fjord Formation. Candidate trackmakers are crocodylian stem group archosaurs; however, a distinct correlation with known osteological taxa from this unit is not currently possible. While the occurrence of sauropodomorph plateosaurs in the bone record links the Greenland assemblage more closer to that from the Germanic Basin of central Europe, here the described footprints suggest a Pangaea-wide exchange.Supplementary material: Three-dimensional model of cf. Brachychirotherium pes–manus set (from MGUH 31233b) from the Upper Triassic Fleming Fjord Formation (Norian–Rhaetian) of East Greenland as pdf, ply and jpg files (3D model created by Oliver Wings; photographs taken by Jesper Milàn) is available at https://doi.org/10.6084/m9.figshare.c.2133546

Fernández-Cabo, J. L., R. Widmann, M. Arce-Blanco, R. Crocetti, J. Xavier, and A. Majano-Majano. "Assessment of wire-frame analysis models of a historical planked timber arch." Proceedings of the Institution of Civil Engineers - Structures and Buildings. 168 (2015): 680-694. AbstractWebsite
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Mendes, Manuel J., Seweryn Morawiec, Tiago Mateus, Andriy Lyubchyk, Hugo Águas, Isabel Ferreira, Elvira Fortunato, Rodrigo Martins, Francesco Priolo, and Isodiana Crupi. "Broadband light trapping in thin film solar cells with self-organized plasmonic nano-colloids." Nanotechnology. 26 (2015): 135202. Abstract
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Fernandes, Susete, Luis Aguirre, Rita Pontes, João Canejo, Pedro Brogueira, Eugene Terentjev, and Maria Helena Godinho. "Cellulose-based nanostructures for photoresponsive surfaces." Cellulose (2015): 1-12. Abstract
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Echeverria, Coro, Pedro L. Almeida, Gabriel Feio, João L. Figueirinhas, and Maria H. Godinho. "A cellulosic liquid crystal pool for cellulose nanocrystals: structure and molecular dynamics at high shear rates." European Polymer Journal. 72 (2015): 72-81. Abstract
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Nico, C. a, R. a Fernandes, M. P. F. a Graça, M. a Elisa, B. A. b Sava, R. C. C. c Monteiro, L. a Rino, and T. a Monteiro. "Erratum: Eu3+ luminescence in aluminophosphate glasses (Journal of Luminescence (2014) 145 (582-587))." Journal of Luminescence. 161 (2015): 465. AbstractWebsite
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Figueiredo, Elin, Beatriz Comendador Rey, João Fonte, Emmanuelle Meunier, Aaron Lackinger, Rui JC Silva, João Pedro Veiga, Carlo Bottaini, José Mirão, and Alexandre Lima. "Estanho antigo no Noroeste Peninsular: uma abordagem multidisciplinar e transfronteiriça para o estabelecimento de uma visão integrada." XI Congresso Ibérico de Arqueometria. 2015. Abstract
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Ito, Y., T. Tochio, S. Fukushima, A. Taborda, J. M. Sampaio, J. P. Marques, F. Parente, P. Indelicato, and J. P. Santos. "Experimental and theoretical determination of the Kα2/Kα1 intensity ratio for zinc." Journal of Quantitative Spectroscopy andRadiative Transfer. 151 (2015): 295-299. AbstractWebsite

X-ray intensity ratios, such as the Kα2/Kα1 ratio, are parameters with a large application in atomic physics and related scientific and technological areas. D.