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2013
Kullberg, J. C., R. B. Rocha, A. F. Soares, J. Rey, P. Terrinha, A. C. Azerêdo, P. Callapez, Duarte, L.V., M. C. Kullberg, L. Martins, J. R. Miranda, C. Alves, J. Mata, J. Madeira, O. Mateus, M. Moreira, and C. R. Nogueira. "A Bacia Lusitaniana: Estratigrafia, Paleogeografia e Tectónica." Geologia de Portugal no contexto da Ibéria. Volume II. Ed. Terrinha Kullberg A. P. J. C. and Dias, R. Araújo. Lisboa: Escolar Editora, 2013. 195-350.kullberg_et_al_2013_a_bacia_lusitaniana.pdf
Cruz, Carla, Sandra D. Santos, Eurico J. Cabrita, and João A. Queiroz. "Binding analysis between l-histidine immobilized and oligonucleotides by SPR and NMR." International Journal of Biological Macromolecules. 56 (2013): 175-180. AbstractWebsite

Saturation transfer difference (STD) NMR technique and surface plasmon resonance (SPR) are used to study amino acid affinity supports–nucleotides interactions with l-histidine amino acid immobilized on a surface as model support. We have immobilized l-histidine ligand on a carboxymethyldextran- modified gold surface intended for surface plasmon resonance and we analyze the binding profiles of synthetic polynucleotides (1–6 base, sugar and backbone) by determining the equilibrium dissociation constant (KD). The SPR binding profile (square-shaped) is identical for all the complexes and the highest binding affinity can be found for polyA6 followed by polyG6 . As expected, the 5′ -mononucleotides have the lowest affinity. To further study the structural aspects of the interaction we investigate the polynucleotide binding preferences to l-histidine chromatography support by STD-NMR spectroscopy. These results revealed that an increase in the number of bases and backbone to 6 units leads to more contacts with the support, where the main driving force for the interaction with polynucleotides are through the base, except for polyC6 , which is mainly through sugar-phosphate backbone. Therefore, the combination of SPR measurements with STD-NMR technique allowed to establish fine details of the molecular recognition process involved in amino acid affinity supports–nucleotides complexes.

dos Santos, Amarante F. P., and C. Cismasiu. "Bridge Hinge-Restrainers Built up of NITI Superelastic Shape-Memory Alloys." New Trends in Smart Technologies . Eds. Christian Boller, and Hartmut Janocha. Saarbrücken: Fraunhofer Verlag, 2013. 195-203.
Santos, Amarante Dos F. P., and Corneliu Cismasiu. "Bridge Hinge-Restrainers Built up of NITI Superelastic Shape-Memory Alloys." New Trends in Smart Technologies . Eds. Christian Boller, and Hartmut Janocha. Saarbrücken: Universität des Saarlandes, Fraunhofer IZFP, 2013. 195-203.urnnbnde0011-n-2564581.pdf
Marques, Pedro Faustino, Carlos Chastre, and Ângela Nunes. "Carbonation service life modelling of RC structures for concrete with Portland and blended cements." Cement and Concrete Composites. 37 (2013): 171-184. Abstractmarques_chastre_et_al._2013.pdfWebsite

The presented work aims at studying the modelling of long term performance of concrete compositions with different proportions of clinker as regards the diffusion of CO2 in concrete – carbonation. The replacing constituents of clinker that will be part of the binder in each concrete composition are limestone filler and low calcium fly ash (FA). The used percentage of FA by weight of binder was of 50%. Concrete compositions were made following standard prescribed requirements to attain service lives of 50 and 100 years as regards concrete performance against reinforcing steel corrosion. Test results of compressive strength and carbonation depth are reported at different curing ages of 28, 90, 180 and 365 days. Carbonation results were used for the implementation of modelling equations in order to estimate the design service life regarding reinforcing steel corrosion. Two performance-based methods were used: safety factor method and probabilistic method, and their results compared with the traditional prescriptive approach. At the age of 28 days the composition with OPC is the only one that reaches the target periods of 50 or 100 years. For the probabilistic method, different curing age results were analysed. For the tested results at 90, 180 and 365 days of age the reliability of some of the compositions with blended cements is within the minimum required, although still far from the higher performance of concrete with OPC.

Correia, Isabel, Teresa Melo, and Francisco Saldanha-da-Gama. "Comparing classical performance measures for a multi-period, two-echelon supply chain network design problem with sizing decisions." Computers and Industrial Engineering. 64 (2013): 366-380. Abstract

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Cunha, Jácome, João Paulo Fernandes, Jorge Mendes, and João Saraiva. "Complexity Metrics for Spreadsheet Models." The 13th International Conference on Computational Science and Its Applications. Eds. B. Murgante, and et al. Vol. 7972. ICCSA'13, 7972. LNCS, 2013. 459-474. Abstracticcsa-sq13.pdf

This paper proposes a set of metrics for the assessment of the complexity of models defining the business logic of spreadsheets. This set can be considered the first step in the direction of building a quality standard for spreadsheet models, that is still to be defined. The computation of concrete metric values has further been integrated under a well-established model-driven spreadsheet development environment, providing a framework for the analysis of spreadsheet models under spreadsheets themselves.

Camarinha-Matos, L. M., J. Goes, and et al Contributing to the Internet of Things. Doctoral Conference on Computing, Electrical and Industrial Systems (DoCEIS’2013). Caparica, Portugal: IFIP Advances in Information and Communication Technology, 2013.
Clement, Thibault, Antonio Pinho Ramos, Miguel Fernandez Ruiz, and Aurelio Muttoni. "Design for punching of prestressed concrete slabs." Structural Concrete. 14 (2013): 157-167. Abstract

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Fernandes, R. M. R. P., J. A. G. Chousal, M. F. S. F. de Moura, and J. Xavier. "Determination of cohesive laws of composite bonded joints under mode II loading." Composites Part B: Engineering. 52 (2013): 269-274. Abstract

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Bras, Ana, Rita Gião, Válter Lúcio, and Carlos Chastre. "Development of an injectable grout for concrete repair and strengthening." Cement and Concrete Composites (2013). AbstractWebsite

This paper deals with the coupled effect of temperature and silica fume addition on rheological, mechanical behaviour and porosity of grouts based on CEMI 42.5R, proportioned with a polycarboxylate-based high range water reducer. Preliminary tests were conducted to focus on the grout best able to fill a fibrous network since the goal of this study was to develop an optimized grout able to be injected in a mat of steel fibers for concrete strengthening. The grout composition was developed based on criteria for fresh state and hardened state properties. For a CEMI 42.5R based grout different high range water reducer dosages (0, 0.2%, 0.4%, 0.5%, 0.7%) and silica fume (SF) dosages (0, 2%, 4%) were tested (as replacement of cement by mass). Rheological measurements were used to investigate the effect of polycarboxylates (PCE) and SF dosage on grout properties, particularly its workability loss, as the mix was to be injected in a matrix of steel fibers for concrete jacketing. The workability behaviour was characterized by the rheological parameters yield stress and plastic viscosity (for different grout temperatures and resting times), as well as the procedures of mini slump cone and funnel flow time. Then, further development focused only on the best grout compositions. The cement substitution by 2% of SF exhibited the best overall behaviour and was considered as the most promising compared to the others compositions tested. Concerning the fresh state analysis, a significant workability loss was detected if grout temperature increased above 35°C. Below this temperature the grout presented a self-levelling behaviour and a life time equal to 45 minutes. In the hardened state, silica fumes increased not only the grout’s porosity but also the grout’s compressive strength at later ages, since the pozzolanic contribution to the compressive strength does not occur until 28 days and beyond.

Afonso, M. L. B., R. M. R. Cardoso, and A. D. Egídio dos Reis. "Dividend problems in the dual risk model." Insurance: Mathematics and Economics. 53.3 (2013): 906-918.
Campos-Rebelo, Rogério, Anikó Costa, and Luís Gomes. "Events for human-system interaction modeling with {IOPT} Petri nets." 6th International Conference on Human System Interactions, {HSI} 2013, Sopot, Poland, June 6-8, 2013. 2013. 56-61. Abstract

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Carrano, M., O. Mateus, and J. Mitchell First definitive association between embryonic Allosaurus bones and prismatoolithus eggs in the Morrison Formation (Upper Jurassic, Wyoming, USA). Annual Meeting of Vertebrate Paleontology. Journal of Vertebrate Paleontology, Program and Abstracts, 2013, 2013. Abstractcarrano_mateus_mitchell_2013_allosaurus_embryos_morrison_svp_abstract.pdf

Despite more than a century of collecting, resulting in one of the best-studied vertebrate fossil records anywhere in the world, the Upper Jurassic Morrison Formation has produced surprisingly few examples of dinosaur eggs associated with embryonic remains. Even more puzzling, none of these seem to pertain to the theropod Allosaurus, one of the most common and best-understood dinosaur taxa in the formation. Here we
report on a dinosaur nest site that has produced both abundant prismatoolithid eggshell and embryonic (or perinatal) bones of Allosaurus from Fox Mesa, Wyoming. This represents the first such discovery for any theropod in the Jurassic of North America. The nest is heavily weathered but contains a few ellipsoid eggshell clusters that suggest an egg size of about 8 x 6.5 cm. Study of the eggshell morphology and microstructure confirms that a single egg type is present throughout, which is indistinguishable from Prismatoolithus coloradensis. All of the identifiable embryonic materials pertain to theropods, and two premaxillae specimens show the five alveoli diagnostic for Allosaurus among Morrison theropods. This confirms the theropod origin of Prismatoolithus eggs and implicates Allosaurus as the specific Morrison parent taxon. As a result, it is now possible to assign several previous discoveries of dinosaur eggs and potential nests to Allosaurus, including the isolated egg from the Cleveland-Lloyd Quarry. This discovery
also calls into question prior assignments of Prismatoolithus eggs to ornithopods, and suggests that more detailed study of such sites is warranted. Prismatoolithus eggshells are also associated with the Upper Jurassic theropod Lourinhanosaurus from Portugal, along with larger embryos that exhibit four premaxillary alveoli.

Silva, Manuel A. G., Hugo Biscaia, and Carlos Chastre. "Influence of Temperature Cycles on Bond between GFRP and Concrete." ACI Structural Journal. 110.6 (2013): 977-988. AbstractWebsite

Reinforced concrete (RC) beams externally strengthened with glass fiber-reinforced polymer (GFRP) strips bonded to the soffit may see their load-carrying capacity reduced due to environmental conditions—especially due to the deterioration of bond between the adhesively bonded laminates and concrete, causing premature failure.
More research has been published on the detachment of the laminate progressing from the anchorage zone than on failure induced by the formation of flexural or shear-flexural cracks in the midspan followed by fiber-reinforced polymer (FRP) separation and failure designated as intermediate crack (IC) debonding. An experimental program to study degradation of the GFRP laminate beam specimens after accelerated temperature cycles, namely: 1) freezing-and-thawing type; and 2) cycles of the same amplitude (40°C [104°F]) and an upper limit approximately 70% of the glass vitreous transition temperature of the resin, Tg, is described.
Effects on the bond stress and ultimate capacity are reported. Substantial differences between shear and bending-induced failure and a decrease of bond stresses and engagement of the laminates on the structural response are analyzed.

Carvalho, H., S. G. Azevedo, and V. Cruz-Machado. "An Innovative Agile and Resilient Index for the Automotive Supply Chain." International Journal of Agile Systems and Management. in press (2013). Abstract

This paper proposes a composite index, called the AR Index, to assess the agility and resilience of automotive companies and their respective supply chains. As a first step, a model to support the AR Index is developed. Next, an AR Index for the automotive supply chain is suggested using a set of relevant Agile and Resilient supply chain practices. The Delphi technique was used to obtain a series of weights for those practices. Finally a case study approach is used to illustrate the application of the AR Index. This study represents an original approach that suggests a unique composite indicator for the Agile and Resilient paradigms in the context of automotive supply chains

Bundaleski, Nenad, Stefano Caporali, Sergey P. Chenakin, Augusto M. C. Moutinho, Orlando M. N. D. Teodoro, and Alexander Tolstogouzov. "Ion-induced fragmentation of imidazolium ionic liquids : TOF-SIMS study." International Journal of Mass Spectrometry. 353 (2013): 19-25.2013_ion-induced_fragmentation_of_imidazolium_ionic_liquids.pdf
Pereira, Pedro, Helena Fino, Mourad Fakhfakh, Fernando Coito, and Mário Ventim-Neves. "LC-VCO Design Challenges in the Nano-Era." Analog/RF and Mixed-Signal Circuit Systematic Design. Eds. Mourad Fakhfakh, Esteban Tlelo-Cuautle, and Rafael Castro-Lopez. Vol. 233. Lecture Notes in Electrical Engineering, 233. Springer Berlin Heidelberg, 2013. 363-379. Abstract

The progressive scaling of CMOS technology towards nanometre sizes has made the implementation of highly integrated systems for the wireless communication systems possible. Additionally, higher speed, lower power consumption and area reduction has been reached. Due to the high-density integration needs, as well as to low cost fabrication, RF applications, such as the LC-voltage controlled oscillator (LC-VCO), are usually implemented in CMOS technology. The complexity of designing LC-VCOs has lead to the development of several design methodologies. This chapter introduces an optimization based methodology for the design of LC-VCOs, where its efficiency is granted by the use of analytical models to characterize the active and passive elements’ behaviour.

Biscaia, Hugo C., Carlos Chastre, and Manuel A. G. Silva. "Linear and nonlinear analysis of bond-slip models for interfaces between FRP composites and concrete." Composites Part B: Engineering. 45 (2013): 1554-1568. AbstractWebsite

The paper analyses different analytical and numerical solutions for the debonding process of the FRP-to-concrete interface on shear tests with the FRP plate submitted to a tensile load in one of its ends. From the point of view of the state of the art, two different ways of finding the bond-slip curve from experiments are discussed and analysed. Essentially, three different linear bond-slip models, one exponential model and another power based function are employed in the numerical process. The results are analysed and compared. The differences found in the stress field along the interface, maximum load, maximum slip, ultimate slip, fracture energy and effective bond length are reported. The load-slip behaviour is also presented for the linear and non-linear models herein studied and the influence of the local bond-slip model on the debonding process is discussed. The numerical integration process used on the present study proved to be coherent with the analytical expressions determined for the linear bond-slip models and allowed to verify that maximum load transmittable to the FRP plate is influenced by the square root of the FRP stiffness and fracture energy even when nonlinear bond-slip models are assumed.

Corcho, A. J., J. D. Silva, and F. Oliveira. "Local and global well-posedness for the critical Schrödinger-Debye system." Proceedings of the American Mathematical Society. 141 (2013): 3485-3499.Website
Caeiro, F., M. I. Gomes, and L. Henriques-Rodrigues A location invariant probability weighted moment EVI-estimator. Notas e Comunicações do CEAUL 30/2013, 2013.2013_30_port-ppwm-final.pdf
Marcelo, Filipa, Catarina Dias, Paulo J. Madeira, Tiago Jorge, Helena M. Florêncio, Javier F. Canada, Eurico J. Cabrita, Jésus Jiménez-Barbero, and Amelia P. Rauter. "Molecular Recognition of Rosmarinic Acid from Salvia sclareoides Extracts by Acetylcholinesterase: A New Binding Site Detected by NMR Spectroscopy." Chemistry: A European Journal. 19 (2013): 6641-6649. AbstractWebsite

Acetylcholinesterase (AChE) inhibition is one of the most currently available therapies for the management of Alzheimer’s disease (AD) symptoms. In this context, NMR spectroscopy binding studies were accomplished to explain the inhibition of AChE activity by Salvia sclareoides extracts. HPLC-MS analyses of the acetone, butanol and water extracts eluted with methanol and acidified water showed that rosmarinic acid is present in all the studied samples and is a major constituent of butanol and water extracts. Moreover, luteolin 4′-O-glucoside, luteolin 3′,7-di-O-glucoside and luteolin 7-O-(6′′-O-acetylglucoside) were identified by MS2 and MS3 data acquired during the LC-MSn runs. Quantification of rosmarinic acid by HPLC with diode-array detection (DAD) showed that the butanol extract is the richest one in this component (134 μg mg−1 extract). Saturation transfer difference (STD) NMR spectroscopy binding experiments of S. sclareoides crude extracts in the presence of AChE in buffer solution determined rosmarinic acid as the only explicit binder for AChE. Furthermore, the binding epitope and the AChE-bound conformation of rosmarinic acid were further elucidated by STD and transferred NOE effect (trNOESY) experiments. As a control, NMR spectroscopy binding experiments were also carried out with pure rosmarinic acid, thus confirming the specific interaction and inhibition of this compound against AChE. The binding site of AChE for rosmarinic acid was also investigated by STD-based competition binding experiments using Donepezil, a drug currently used to treat AD, as a reference. These competition experiments demonstrated that rosmarinic acid does not compete with Donepezil for the same binding site. A 3D model of the molecular complex has been proposed. Therefore, the combination of the NMR spectroscopy based data with molecular modelling has permitted us to detect a new binding site in AChE, which could be used for future drug development.

Rodríguez-Martínez, E. V., R. M. R. Cardoso, and A. D. Egídio dos Reis. "Moments of Dividends and Optimal Expected Dividends in the Erlang(n) dual risk model." ASTIN Colloquium 2013. The Hague, Netherlands 2013.
Sallem, Amin, Pedro Pereira, Mourad Fakhfakh, and Helena Fino. "A Multi-objective Simulation Based Tool: Application to the Design of High Performance LC-VCOs." Technological Innovation for the Internet of Things. Eds. LuisM. Camarinha-Matos, Slavisa Tomic, and Paula Graça. Vol. 394. IFIP Advances in Information and Communication Technology, 394. Portugal: Springer Berlin Heidelberg, 2013. 459-468. Abstract

The continuing size reduction of electronic devices imposes design challenges to optimize the performances of modern electronic systems, such as: wireless services, telecom and mobile computing. Fortunately, those design challenges can be overcome thanks to the development of Electronic Design Automation (EDA) tools. In the analog, mixed signal and radio-frequency (AMS/RF) domains, circuit optimization tools have demonstrated their usefulness in addressing design problems taking into account downscaling technological aspects. Recent advances in EDA have shown that the simulation-based sizing technique is a very interesting solution to the ‘complex’ modelling task in the circuit design optimization problem. In this paper we propose a multi-objective simulation-based optimization tool. A CMOS LC-VCO circuit is presented to show the viability of this tool. The tool is used to generate the Pareto front linking two conflicting objectives, namely the VCO Phase Noise and Power Consumption. The accuracy of the results is checked against HSPICE/RF simulations.

Pimenta, Jorge, Aldino Viegas, João Sardinha, Ivo C. Martins, Eurico J. Cabrita, Carlos M. G. A. Fontes, Jose A. M. Prates, and Rosa M. L. N. Pereira. "NMR Solution Structure and SRP54M predicted interaction of the N-Terminal sequence (1-30) of the ovine Doppel protein." Peptides. 49 (2013): 32-40. AbstractWebsite

Prion protein (PrPC) biosynthesis involves a multi-step process that includes translation and post-translational modifications. While PrP has been widely investigated, for the homolog Doppel (Dpl), limited knowledge is available. In this study, we focused on a vital step of eukaryotic protein biosynthesis: targeting by the signal recognition particle (SRP). Taking the ovine Dpl (OvDpl(1-30)) peptide as a template, we studied its behavior in two different hydrophobic environments using CD and NMR spectroscopy. In both trifluoroethanol (TFE) and dihexanoyl-sn-glycero-3-phosphatidylcholine (DHPC), the OvDpl(1-30) peptide revealed to fold in an alpha-helical conformation with a well-defined central region extending from residue Cys8 until Ser22. The NMR structure was subsequently included in a computational docking complex with the conserved M-domain of SRP54 protein (SRP54M), and further compared with the N-terminal structures of mouse Dpl and bovine PrPC proteins. This allowed the determination of (i) common predicted N-terminal/SRP54M polar contacts (Asp331, Gln335, Glu365 and Lys432) and (ii) different N–C orientations between prion and Dpl peptides at the SRP54M hydrophobic groove, that are in agreement with each peptide electrostatic potential. Together, these findings provide new insights into the biosynthesis of prion-like proteins. Besides they also show the role of protein conformational switches in signalization toward the endoplasmic membrane, a key event of major significance in the cell cycle. They are thus of general applicability to the study of the biological function of prion-like as well as other proteins.