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2012
Sousa, Teresa. "Friendship Decompositions of Graphs: The general problem." Open Journal of Applied Sciences. Vol. 2. No. 4B (2012): 30-33. Abstractgeneral-friendship.pdfWebsite

A friendship graph is a graph consisting of cliques sharing a common vertex. In this paper we investigate the maximum number of elements in an optimal friendship decomposition of graphs of order n. We obtain upper and lower bounds for this number. These bounds relate this problem with the classical Ramsey numbers.

Cunha, Jácome, João Paulo Fernandes, and João Saraiva. "From Relational ClassSheets to UML+OCL." Proceedings of the Software Engineering Track at the 27th Annual ACM Symposium On Applied Computing (SAC 2012). ACM, 2012. 1151-1158. Abstractsac-se12.pdf

Spreadsheets are among the most popular programming languages in the world. Unfortunately, spreadsheet systems were not tailored from scratch with modern programming language features that guarantee, as much as possible, program correctness. As a consequence, spreadsheets are populated with unacceptable amounts of errors. In other programming language settings, model-based approaches have been proposed to increase productivity and program effectiveness. Within spreadsheets, this approach has also been followed, namely by ClassSheets. In this paper, we propose an extension to ClassSheets to allow the specification of spreadsheets that can be viewed as relational databases. Moreover, we present a transformation from ClassSheet models to UML class diagrams enriched with OCL constraints. This brings to the spreadsheet realm the entire paraphernalia of model validation techniques that are available for UML.

Mendes, Ana Sofia, Maria Amalia Botelho, Ana Luisa Papoila, João Viegas, Daniel Aelenei, Paixão, P. Paquete, Iolanda Caires, Susana Azevedo, Pedro Martins, J. Martins, C. Pedro, P. Neves, Nuno Neuparth, and João Teixeira. "Geria Project preliminary study on indoor air quality and health related quality of life in elderly care centers." CISE 2012, Conference. 2012. Abstract

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Hendrix, Eligius M. T., Leocadio G. Casado, and Paula Amaral. "Global Optimization Simplex Bisection Revisited Based on Considerations by Reiner Horst." Lecture Notes in Computer Science - ICSSA2012 . 7335 (2012): 159-173. AbstractWebsite

In this paper, the use of non-optimality spheres in a simplicial branch and bound (B&B) algorithm is investigated. In this context, some considerations regarding the use of bisection on the longest edge in relation with ideas of Reiner Horst are reminded. Three arguments highlight the merits of bisection of simplicial subsets in B&B schemes.

Guirgis, Bassem, Cláudia Sá e Cunha, Inês Gomes, Miguel Cavadas, Isabel Silva, Gonçalo Doria, Gregory Blatch, Pedro Baptista, Eulália Pereira, Hassan Azzazy, Maria Mota, Miguel Prudêncio, and Ricardo Franco. "Gold nanoparticle-based fluorescence immunoassay for malaria antigen detection." Analytical and Bioanalytical Chemistry. 402.3 (2012): 1019-1027.
Azzazy, Hassan M. E., M. H. Mansour Mai, M. Samir Tamer, and Ricardo Franco. "Gold nanoparticles in the clinical laboratory: principles of preparation and applications." Clinical Chemistry and Laboratory Medicine. 50.2 (2012): 193.
Krabbenhoft, K., A. V. Lyamin, J. Huang, and M. Vicente da Silva. "Granular contact dynamics using mathematical programming methods." Computers and Geotechnics. 43 (2012): 165-176. Abstract

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Krabbenhoft, K., J. Huang, M. Vicente da Silva, and A. V. Lyamin. "Granular contact dynamics with particle elasticity." Granular Matter. 14.5 (2012): 607-619. Abstract

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Sousa, Teresa. "The H-Decomposition Problem for Graphs." Applied Mathematics. 3.11 (2012): 1719-1722. AbstractH-decomp-problem.pdfWebsite

The concept of H-decompositions of graphs was first introduced by Erdös, Goodman and Pósa in 1966, who were motivated by the problem of representing graphs by set intersections. Given graphs G and H, an 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 graph isomorphic to H. Let Ф(n,H) be the smallest number Ф, such that, any graph of order n admits an H-decomposition with at most Ф parts. The exact computation of Ф(n,H) for an arbitrary H is still an open problem. Recently, a few papers have been published about this problem. In this survey we will bring together all the results about H-decompositions. We will also introduce two new related problems, namely Weighted H-Decompositions of graphs and Monochromatic H-Decompositions of graphs.

Varandas, J. N., R. Silva, M. A. G. Silva, N. Lopes, and P. Hölscher. "The Impact of Rail Corrugation on the Degradation of Ballast." Proceedings of the First International Conference on Railway Technology: Research, Development and Maintenance. Ed. J. Pombo. Las Palmas de Gran Canaria, Spain: Civil-Comp Press, 2012. 543-546. Abstract

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"Improving science and mathematics education with computational modelling in interactive engagement environments." AIP Conference Proceedings, vol. 1479: Numerical Analysis and Applied Mathematics ICNAAM 2012 - International Conference of Numerical Analysis and Applied Mathematics. American Institute of Physics, 2012. 1806-1809.
Estêvão M. E., Carvalho L. C., Freitas Gomes Viegas Manso Fernandes Cabrita Erhardt Marques Ma M. A. A. J. "Indole based cyclooxygenase inhibitors: synthesis, biological evaluation, docking and NMR screening." Eur. J. Med. Chem.. 54.- (2012): 823-833.
Estevão, Mónica S., Luísa C. R. Carvalho, Marisa Freitas, Ana Gomes, Aldino Viegas, João Manso, Stefan Erhadrt, Eurico J. Cabrita, and Maria Manuel B. Marques. "Indole based cyclooxygenase inhibitors: synthesis, biological evaluation, docking and NMR screening." European Journal of Medicinal Chemistry. 54 (2012): 823-833. Abstract

The close structural similarity between the two cyclooxygenase (COXs) isoforms and the absence of selective inhibitors without side effects continues to stimulate the development of novel approaches towards selective anti-inflammatory drugs. In the present study a small library of new indolic compounds involving two different substitutions patterns at the indole scaffold was synthesized. In order to establish a relation between the spatial distribution of known functional groups related with inhibitory activity, two substitution patterns were explored: one with substituents at N-1, C-3, C-5 positions and another at C-2, C-3 and C5 positions. Accordingly, indole positions C-5, C-3 and N-1 were substituted with: sulfonamide or methylsulfone at C-5, p-halo-benzyl group at C-3, and an alkyl chain with a trifluoromethyl group at N-1. Alternatively, a p-halo-benzyl group was introduced at C-2, leaving the indolic nitrogen free. Inhibitory studies were performed and the activity results obtained against both COXs isoforms were rationalized based on docking and NMR studies. Docking studies show that dialkyation at C-2 and C-3 favors a binding with an orientation similar to that of the known selective inhibitor SC-558. From the tested compounds, this substitution pattern is correlated with the highest inhibitory activity and selectivity: 70% COX-2 inhibition at 50 M, and low COX-1 inhibition (18±9%). Additionally, Saturation Transfer Difference NMR experiments reveal different interaction patterns with both COXs isoforms that may be related with different orientations of the sulfonamide group in the binding pocket. Despite the moderated inhibitory activities found, this study represents an innovative approach towards COXs inhibitory activity rationalization and to the design of anti-inflammatory drugs.

Cano, Manuela, Susana Nogueira, Ana Luisa Papoila, F. Aguiar, Pedro Martins, J. Marques, Iolanda Caires, J. Martins, C. Pedro, P. Paixão, J. Rosado-Pinto, Paula Leiria-Pinto, Daniel Aelenei, Ana Mendes, João Teixeira, M. C. Proença, and Nuno Neuparth. "Indoor Air Quality in Portuguese Children Day Care Centers ? ENVIRH Project." The Second International Conference on Building Energy and Environment (COBEE). 978-0-9816881-9-0; 0-9816881-9-5. 2012. Abstract

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Azevedo, S. G., H. Carvalho, S. Duarte, and V. Cruz-Machado. "Influence of Green and Lean Upstream Supply Chain Management Practices on Business Sustainability." Engineering Management, IEEE Transactions on. 59 (2012): 1-13. AbstractWebsite

Green and lean paradigms have been adopted by companies in order to manage their relationships with suppliers in a supply chain management context, but nearly always separately and with little understanding of their influence on company performance. This paper proposes a theoretical framework for the analysis of the influence of green and lean upstream supply chain management practices on the sustainable development of businesses. To attend this objective, a set of performance measures covering economic (operational cost, environmental cost, and inventory cost), environmental (business wastage, green image, and CO2 emission), and social (corruption risk, supplier screening and local supplier) perspectives is proposed. An explanatory case study was conducted at a Portuguese automaker to test qualitatively the validity of the proposed theoretical framework. From the case study, a model is suggested, which encompasses the relationships between green and lean upstream supply chain practices and sustainable business development.

Vieira, Manuel V. C. "Interior-point methods based on kernel functions for symmetric optimization." Optimization Methods and Software. 27.3 (2012): 513-537. Abstract

We present a generalization to symmetric optimization of interior-point methods for linear optimization based on kernel functions. Symmetric optimization covers the three most common conic optimization problems: linear, second-order cone and semi-definite optimization problems. Namely, we adapt the interior-point algorithm described in Peng et al. [Self-regularity: A New Paradigm for Primal–Dual Interior-point Algorithms. Princeton University Press, Princeton, NJ, 2002.] for linear optimization to symmetric optimization. The analysis is performed through Euclidean Jordan algebraic tools and a complexity bound is derived.

Lapa, N., R. Barbosa, and B. Mendes. "Intrinsic properties of new materials for civil engineering works based on the reuse of MSWI bottom ashes: chemical and ecotoxicological assessment." Urban Mining: A global cycle approach to resource recovery from solid waste. Eds. R. Cossu, V. Salieri, and V. Bisinella. Padova: CISA Publisher, 2012. 298-307.
Brás, C. P., W. W. Hager, and J. J. Júdice. "An investigation of feasible descent algorithms for estimating the condition number of a matrix." TOP - Journal of the Spanish Society of Statistics and Operations Research. 20 (2012): 791-809. AbstractWebsite

Techniques for estimating the condition number of a nonsingular matrix are developed. It is shown that Hager's 1-norm condition number estimator is equivalent to the conditional gradient algorithm applied to the problem of maximizing the 1-norm of a matrix-vector product over the unit sphere in the 1-norm. By changing the constraint in this optimization problem from the unit sphere to the unit simplex, a new formulation is obtained which is the basis for both conditional gradient and projected gradient algorithms. In the test problems, the spectral projected gradient algorithm yields condition number estimates at least as good as those obtained by the previous approach. Moreover, in some cases, the spectral gradient projection algorithm, with a careful choice of the parameters, yields improved condition number estimates.

Zajega, F., Mancas M., Ben Mandhkour R., Leroy J., Riche N., Rocca F., Rybarczyk Y., and Dutoit T. "KinAct: the attentive social game demonstration." 11th Asian Conference on Computer Vision. Daejeon, Korea 2012. copy.pdf
Araújo, R., R. Castanhinha, O. Mateus, and R. Martins Late Jurassic theropod embryos from Porto das Barcas, Lourinhã formation, Portugal. Journal of Vertebrate Paleontology, Program and Abstracts, 2012, ISSN 1937-2809 ., 2012. Abstractaraujo_et_al_mateus_2012_dinosaur_eggs_portugal_svp_2012_abstract_book_meeting_abstracts.pdf.pdf

A clutch of several crushed eggs and embryos from the Late Jurassic (near the Kimmeridgian-Tithonian
boundary), Lourinhã Formation, Portugal contains a complete maxilla, erupted and scattered teeth,
and presacral vertebrae. The maxilla bears four teeth separated by individualized interdental plates,
the dorsal process of the maxilla is confluent with the maxillary body, the ventral rim of the antorbital
fossa is parallel to the tooth row, and the anterior border of the maxilla forms a right angle with the
ventral margin. The teeth are conical and recurved distally with carinae on mesial and distal sides. The
vertebrae are amphiplatyan, with a ventral pair of neurovascular foramina and heavily pitted articular
facets. These fossils allow unambiguous association of basal theropod osteology (Megalosauroidea) with
a new eggshell morphotype. Synchrotron micro-computed tomographic scanning (SRμCT), scanning
electron microscopy, and thin-sections under polarized and normal light revealed that the outer
ornamentation of the eggshell is composed of anastomosing ridges and islets, the pores communicate
near the outer region of the eggshells, and in radial section they are irregular canals that ramify towards
the surface. Micro-proto induced x-ray emission (micro-PIXE) analysis of the eggshell (excluding pores)
revealed the presence of Mg, Fe, Mn (0.33%, 0.27% and 0.18%, respectively) and several trace elements,
with a corresponding loss of Ca (39.4% detected but 40.0% expected for calcite), which suggests minimal
eggshell diagenesis. The eggshells do not luminesce, which could imply that no diagenetic alteration
took effect. However, the quenching effect of Fe2+ has to be taken into consideration. Conversely,
luminescence is observed in the pores since they are filled with sediment, composed of phyllosilicates,
as revealed by SRμCT, micro-PIXE and x-ray diffraction analyses.

Guimarães, D., M. L. Carvalho, M. Becker, A. von Bohlen, V. Geraldes, I. Rocha, and J. P. Santos. "Lead concentration in feces and urine of exposed rats by x-ray fluorescence and electrothermal atomic absorption spectrometry." X-Ray Spectrom.. 41 (2012): 80. Abstract

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"Learning introductory physics with computational modelling and interactive environments." Proceedings of the GIREP-EPEC 2011 Conference - Physics Alive. Jyvaskyla: University of Jyvaskyla, 2012. 208-213.
Carvalho, H., J. G. Tavares, and V. Cruz-Machado. "A Mapping Framework for Supply Chain Resilience Assessment." International Journal of Logistics Systems and Management. 12 (2012): 354-373. AbstractWebsite

Supply chains (SCs) may experience instability induced by disturbances such as extreme climate conditions or accidents. These events can cause severe negative effects on SCs, jeopardising the on-time delivery of products and services to customers. This paper proposes a mapping framework to improve SC resilience to such events, avoiding possible failure modes. The proposed mapping framework allows identification of the current SC operation and possible transition states, together with points of vulnerability. An illustrative example of the framework applied to a real-life wine SC is presented.

Rebelo, M., T. Diogo, and S. McKee. "A Mathematical Treatment of the Fluorescence Capillary-Fill Device." SIAM, J. Applied Mathematics. 72.4 (2012): 1081-1112.