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2014
Sabino, André, Armanda Rodrigues, Miguel Goulão, and João Gouveia. "Indirect Keyword Recommendation." International Conference on Intelligent Agent Technology, WIC 2014. Warsaw, Poland: IEEE/WIC/ACM, 2014. Abstractsabino2014wic.pdf

Helping users to find useful contacts or potentially interesting subjects is a challenge for social and productive
networks. The evidence of the content produced by users must be considered in this task, which may be simplified by the use of the meta-data associated with the content, i.e., the categorization supported by the network – descriptive keywords, or tags. In this paper we present a model that enables keyword discovery
methods through the interpretation of the network as a graph, solely relying on keywords that categorize or describe productive items. The model and keyword discovery methods presented in this paper avoid content analysis, and move towards a generic approach to the identification of relevant interests and, eventually,
contacts. The evaluation of the model and methods is executed by two experiments that perform frequency and classification analyses over the Flickr network. The results show that we can efficiently recommend keywords to users.

Gonçalves, Sara, Hugo Lourenço, and Sérgio Silva Otimização automática de aplicações web usando templates client-side. INForum 2014 - Actas do 6º Simpósio de Informática., 2014.
S.C. Ferreira, A. Conde, Ángeles Arenas Rocha Velhinho M. L. A. A. "Anodization mechanism on SiC nanoparticle reinforced Al matrix composites." Materials. 7 (2014): 8151-8167.
Viegas, M. C., António Moniz, and P. T. Santos. "Artisanal fishermen contribution for the integrated and sustainable coastal management - application of strategic SWOT analysis." Procedia - Social and Behavioral Sciences. 2014.120 (2014): 257-267.Website
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.

Karlovich, Alexei Yu. "Boundedness of pseudodifferential operators on Banach function spaces." Operator Theory, Operator Algebras and Applications. Operator Theory: Advances and Applications, 242. Eds. Maria Amélia Bastos, Amarino Lebre, Stefan Samko, and Ilya M. Spitkovsky. Basel: Birkhäuser/Springer, 2014. 185-195. Abstract

We show that if the Hardy-Littlewood maximal operator is bounded on a separable Banach function space \(X(\mathbb{R}^n)\) and on its associate space \(X'(\mathbb{R}^n)\), then a pseudodifferential operator \(\operatorname{Op}(a)\) is bounded on \(X(\mathbb{R}^n)\) whenever the symbol \(a\) belongs to the Hörmander class \(S_{\rho,\delta}^{n(\rho-1)}\) with \(0<\rho\le 1\), \(0\le\delta<1\) or to the the Miyachi class \(S_{\rho,\delta}^{n(\rho-1)}(\varkappa,n)\) with \(0\le\delta\le\rho\le 1\), \(0\le\delta<1\), and \(\varkappa>0\). This result is applied to the case of variable Lebesgue spaces \(L^{p(\cdot)}(\mathbb{R}^n)\).

Strganac, C., J. Salminen, LL Jacobs, KM Ferguson, M. J. Polcyn, O. Mateus, AS Schulp, ML Morais, TS Tavares, and AO. Gonçalves. "Carbon isotope stratigraphy and 40Ar/39Ar age of the Cretaceous South Atlantic coast, Namibe Basin, Angola." Journal of African Earth Sciences. onine (2014): 1-11. Abstractstrganac_et_al_2014_carbon_isotope_stratigraphy_magnetostratigraphy_and_40ar_39ar_age_of.pdfWebsite

We present the δ13C and paleomagnetic stratigraphy for marine strata at the coast of southern Angola, anchored by an intercalated basalt with a whole rock 40Ar/39Ar radiometric age of 84.6 ± 1.5 Ma, being consistent with both invertebrate and vertebrate biostratigraphy. This is the first African stable carbon isotope record correlated to significant events in the global carbon cycle spanning the Late Cenomanian to Early Maastrichtian. A positive ∼ 3‰ excursion seen in bivalve shells below the basalt indicates the Cenomanian-Turonian Boundary Event at 93.9 Ma, during Oceanic Anoxic Event 2. Additional excursions above the basalt are correlated to patterns globally, including a negative ∼ 3‰ excursion near the top of the section interpreted as part of the Campanian-Maastrichtian Boundary Events. The age of the basalt ties the studied Bentiaba section to a pulse of Late Cretaceous magmatic activity around the South Atlantic and significant tectonic activity, including rotation, of the African continent.

Karlovich, Alexei Yu., and Ilya M. Spitkovsky. "The Cauchy singular integral operator on weighted variable Lebesgue spaces." Concrete Operators, Spectral Theory, Operators in Harmonic Analysis and Approximation. Operator Theory: Advances and Applications, 236. Eds. Manuel Cepedello Boiso, Håkan Hedenmalm, Marinus A. Kaashoek, Alfonso Montes Rodríguez, and Sergei Treil. Basel: Birkhäuser, 2014. 275-291. Abstract

Let \(p:\mathbb{R}\to(1,\infty)\) be a globally log-Hölder continuous variable exponent and \(w:\mathbb{R}\to[0,\infty]\) be a weight. We prove that the Cauchy singular integral operator \(S\) is bounded on the weighted variable Lebesgue space \(L^{p(\cdot)}(\mathbb{R},w)=\{f:fw\in L^{p(\cdot)}(\mathbb{R})\}\) if and only if the weight \(w\) satisfies $$ \sup_{-\infty < a < b < \infty} \frac{1}{b-a} \|w\chi_{(a,b)}\|_{p(\cdot)} \|w^{-1}\chi_{(a,b)}\|_{p'(\cdot)}<\infty \quad (1/p(x)+1/p'(x)=1). $$

Jacobs, L., M. Polcyn, O. Mateus, M. Scott, J. Graf, J. Kappelman, B. Jacobs, A. Schulp, M. Morais, and O. Goncalves. "Cenozoic vertebrates of coastal Angola." Journal of Vertebrate Paleontology, Program and Abstracts, 2014 (2014): 153.jacobs_et_al._2014_cenozoic_vertebrates_of_coastal_angola.pdf
Silva, Edgar M., Rogério Campos-Rebelo, Takahiro Hirashima, Filipe Moutinho, Pedro Maló, Anikó Costa, and Luís Gomes. "Communication support for Petri nets based distributed controllers." 23rd {IEEE} International Symposium on Industrial Electronics, {ISIE} 2014, Istanbul, Turkey, June 1-4, 2014. 2014. 1111-1116. Abstract

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Stockdale, M., M. Benton, and O. Mateus. "Cracking dinosaur endothermy: paleophysiology unscrambled." Journal of Vertebrate Paleontology. Program and Abstracts, 2014 (2014): 235-236.stockdale_et_al_2014_eggshells_abstract_svp.pdf
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.

Garde, F., A. Lenoir, A. Scognamiglio, D. Aelenei, D. Waldren, HN Rostvik, J. Ayoub, L. Aelenei, M. Donn, M. Tardif, and others. "Design of net zero energy buildings: Feedback from international projects." Energy Procedia. 61 (2014): 995-998. Abstract

The International Energy Agency (IEA), through the Solar Heating and Cooling programme (SHC) Task 40 and the Energy Conservation in Buildings and Community Systems programme (ECBCS, now named EBC) Annex 52, works towards developing a common understanding and setting up the basis for an international definition framework for Net Zero Energy Buildings (Net ZEBs). One of the subtasks of this programme?SubTaskC focuses benchmarking the Net ZEBs around the world to identify the innovative solutions sets that makes up this new type of building. This paper presents an overview of the work conducted by the participants of Subtask C and of Zero Energy Building projects that have been identified.

Carção, Tiago, Marco Couto, Jácome Cunha, João Paulo Fernandes, and João Saraiva. "Detecting Anomalous Energy Consumption in Android Applications." Proceedings of the 18th Brazilian Symposium on Programming Languages. SBLP '14. 2014. 77-91. Abstractsblp14.pdf

The use of powerful mobile devices, like smartphones, tablets and laptops, are changing the way programmers develop software. While in the past the primary goal to optimize software was the run time optimization, nowadays there is a growing awareness of the need to reduce energy consumption. This paper presents a technique and a tool to detect anomalous energy consumption in Android applications, and to relate it directly with the source code of the application. We propose a dynamically calibrated model for energy consumption for the Android ecosystem, and that supports different devices. The model is then used as an API to monitor the application execution: first, we instrument the application source code so that we can relate energy consumption to the application source code; second, we use a statistical approach, based on fault-localization techniques, to localize abnormal energy consumption in the source code.

Silva, F. G. A., J. J. L. Morais, N. Dourado, J. Xavier, F. A. M. Pereira, and M. F. S. F. de Moura. "Determination of cohesive laws in wood bonded joints under mode II loading using the ENF test." International Journal of Adhesion and Adhesives. 51 (2014): 54-61. AbstractWebsite

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Seabra, J., Rybarczyk, Y., Batista, A., Rybarczyk, P., Lebret, M.C., and Vernay D. "Development of a wearable monitoring system for service dogs." IEEE Roman’14, Workshop on Wearable Technology and Human-Wearable Robot Interaction. Edinburgh, UK 2014.
Seabra, J., Y. Rybarcsik, and A. Batista Development of a Wearable Monitoring System for Service Dogs. IEEE Roman WorkShop. Edinburgh, 2014.service_dogs.pdf
Marzola, M., O. Mateus, A. Schulp, L. Jacobs, M. Polcyn, and V. Pervov. "Early Cretaceous tracks of a large mammaliamorph, a crocodylomorph, and dinosaurs from an Angolan diamond mine." Journal of Vertebrate Paleontology, Program and Abstracts, 2014 (2014): 181.marzola_et_al_2014._cretaceous_tracks_mammaliamorph_a_crocodilomorph_angolan_diamond_mine.pdf
Soares, PI, AM Alves, LC Pereira, JT Coutinho, IM Ferreira, CM Novo, and J. P. Borges. "Effects of surfactants on the magnetic properties of iron oxide colloids." J Colloid Interface Sci.. 419 (2014): 46-51. AbstractWebsite

Iron oxide nanoparticles are having been extensively investigated for several biomedical applications such as hyperthermia and magnetic resonance imaging. However, one of the biggest problems of these nanoparticles is their aggregation.

Taking this into account, in this study the influence of three different surfactants (oleic acid, sodium citrate and Triton X-100) each one with various concentrations in the colloidal solutions stability was analyzed by using a rapid and facile method, the variation in the optical absorbance along time.

The synthesized nanoparticles through chemical precipitation showed an average size of 9 nm and a narrow size distribution. X-ray diffraction pattern and Fourier Transform Infrared analysis confirmed the presence of pure magnetite. SQUID measurements showed superparamagnetic properties with a blocking temperature around 155 K. In addition it was observed that neither sodium citrate nor Triton X-100 influences the magnetic properties of the nanoparticles. On the other hand, oleic acid in a concentration of 64 mM decreases the saturation magnetization from 67 to 45 emu/g. Oleic acid exhibits a good performance as stabilizer of the iron oxide nanoparticles in an aqueous solution for 24 h, for concentrations that lead to the formation of the double layer.

Barros, Teresa M., Krasimira T. Petrova, Paula Correia da Silva, and Ana Paula Esteves. "Efficient Microwave-Assisted Synthesis of 1’,2,3,3’,4,4’,6-Hepta-O-Benzyl-Sucrose and 1’,2,3,3’,4,4’-Hexa-O-Benzylsucrose." Carbohydrate Chemistry: Proven Synthetic Methods, Volume 2, Chapter 14. Eds. Gijsbert van der Marel, and Jeroen Codee. CRC Press, Taylor & Francis Group, 2014. 103-123.
Cunha, Jácome, João Paulo Fernandes, Jorge Mendes, Rui Pereira, and João Saraiva. "Embedding Model-Driven Spreadsheet Queries in Spreadsheet Systems." Proceedings of the 2014 IEEE Symposium on Visual Languages and Human-Centric Computing. VLHCC '14. Washington, DC, USA: IEEE Computer Society, 2014. 151-154. Abstractvlhcc14.pdf

Spreadsheets are widely used not only to define mathematical expressions, but also to store large and complex data. To query such data is usually a difficult task to perform, usually for end user. In this work we embed the textual query language in the model-driven spreadsheet environment as a spreadsheet itself. The result is an expressive and powerful query environment that has knowledge of the business logic defined by the spreadsheet data (the spreadsheet model) to guide end users constructing correct queries.

Cunha, Jácome, João P. Fernandes, Jorge Mendes, and João Saraiva. "Embedding, Evolution, and Validation of Spreadsheet Models in Spreadsheet Systems." IEEE Transactions on Software Engineering. 41.3 (2014): 241-263. Abstracttse14.pdfWebsite

This paper proposes and validates a model-driven software engineering technique for spreadsheets. The technique that we envision builds on the embedding of spreadsheet models under a widely used spreadsheet system. This means that we enable the creation and evolution of spreadsheet models under a spreadsheet system. More precisely, we embed ClassSheets, a visual language with a syntax similar to the one offered by common spreadsheets, that was created with the aim of specifying spreadsheets. Our embedding allows models and their conforming instances to be developed under the same environment. In practice, this convenient environment enhances evolution steps at the model level while the corresponding instance is automatically co-evolved. Finally, we have designed and conducted an empirical study with human users in order to assess our technique in production environments. The results of this study are promising and suggest that productivity gains are realizable under our model-driven spreadsheet development setting.

Cunha, Jácome, João P. Fernandes, Jorge Mendes, and João Saraiva Embedding, Evolution, and Validation of Spreadsheet Models in Spreadsheet Systems. HASLab - High-Assurance Software Laboratory & Universidade do Minho, 2014. Abstracttr_embedding.pdf

This paper proposes and validates a model-driven software engineering technique for spreadsheets. The technique that we envision builds on the embedding of spreadsheet models under a widely used spreadsheet system, so that models and their conforming instances are developed under the same environment. In practice, this convenient environment enhances evolution steps at the model level while the corresponding instance is automatically co-evolved. Finally, we have designed and conducted an empirical study with human users in order to assess our technique in production environments. The results of this study are promising and suggest that productivity gains are realizable under our model-driven spreadsheet development setting.

Silva, Micael, Angelo Miguel Figueiredo, and Eurico J. Cabrita. "Epitope mapping of imidazolium cations in ionic liquid–protein interactions unveils the balance between hydrophobicity and electrostatics towards protein destabilisation." Phys. Chem. Chem. Phys. . in press (2014). Abstract

We investigated imidazolium-based ionic liquid (IL) interactions with human serum albumin (HSA) to discern the level of cation interactions towards protein stability. STD-NMR spectroscopy was used to observe the imidazolium IL protons involved in direct binding and to identify the interactions responsible for changes in Tm as accessed by differential scanning calorimetry (DSC). Cations influence protein stability less than anions but still significantly. It was found that longer alkyl side chains of imidazolium- based ILs (more hydrophobic) are associated with a higher destabilisation effect on HSA than short-alkyl groups (less hydrophobic). The reason for such destabilisation lies on the increased surface contact area of the cation with the protein, particularly on the hydrophobic contacts promoted by the terminus of the alkyl chain. The relevance of the hydrophobic contacts is clearly demonstrated by the introduction of a polar moiety in the alkyl chain: a methoxy or alcohol group. Such structural modification reduces the degree of hydrophobic contacts with HSA explaining the lesser extent of protein destabilisation when compared to longer alkyl side chain groups: above [C2mim]+. Competition STD-NMR experiments using [C2mim]+, [C4mim]+ and [C2OHmim]+ also validate the importance of the hydrophobic interactions. The combined effect of cation and anion interactions was explored using 35Cl NMR. Such experiments show that the nature of the cation has no influence on the anion–protein contacts, still the nature of the anion modulates the cation–protein interaction. Herein we propose that more destabilising anions are likely to be a result of a partial contribution from the cation as a direct consequence of the different levels of interaction (cation–anion pair and cation–protein).

Cunha, Jácome, João Paulo Fernandes, Jorge Mendes, Rui Pereira, and João Saraiva. "ES-SQL: Visually Querying Spreadsheets." Proceedings of the 2014 IEEE Symposium on Visual Languages and Human-Centric Computing. VLHCC '14. Washington, DC, USA: IEEE Computer Society, 2014. 203-204. Abstractvlhcc14-td.pdf

This paper presents ES-SQL, an embedded tool for visually constructing queries over spreadsheets. This tool provides an expressive query environment which has knowledge on the business logic of spreadsheets, and by this knowledge it assists the user in defining the intended queries.