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2017
Tschopp, Emanuel, and Octávio Mateus. "Osteology of Galeamopus pabsti sp. nov. (Sauropoda: Diplodocidae), with implications for neurocentral closure timing, and the cervico-dorsal transition in diplodocids." PeerJ. 5 (2017): e3179. Abstracttschopp__mateus_2017_osteology_of_galeamopus_pabsti_sp.__nov._sauropoda__diplodocidae_.pdfWebsite

Diplodocids are among the best known sauropod dinosaurs. Numerous specimens of currently 15 accepted species belonging to ten genera have been reported from the Late Jurassic to Early Cretaceous of North and South America, Europe, and Africa. The highest diversity is known from the Upper Jurassic Morrison Formation of the western United States: a recent review recognized 12 valid, named species, and possibly three additional, yet unnamed ones. One of these is herein described in detail and referred to the genus \textit{Galeamopus}. The holotype specimen of \textit{Galeamopus pabsti} sp. nov., SMA 0011, is represented by material from all body parts but the tail, and was found at the Howe-Scott Quarry in the northern Bighorn Basin in Wyoming, USA. Autapomorphic features of the new species include a horizontal canal on the maxilla that connects the posterior margin of the preantorbital and the ventral margin of the antorbital fenestrae, a vertical midline groove marking the sagittal nuchal crest, the presence of a large foramen connecting the postzygapophyseal centrodiapophyseal fossa and the spinopostzygapophyseal fossa of mid- and posterior cervical vertebrae, a very robust humerus, a laterally placed, rugose tubercle on the concave proximal portion of the anterior surface of the humerus, a relatively stout radius, the absence of a distinct ambiens process on the pubis, and a distinctly concave posteroventral margin of the ascending process of the astragalus. In addition to the holotype specimen SMA 0011, the skull USNM 2673 can also be referred to \textit{Galeamopus pabsti}. Histology shows that the type specimen SMA 0011 is sexually mature, although neurocentral closure was not completed at the time of death. Because SMA 0011 has highly pneumatized cervical vertebrae, the development of the lamination appears a more important indicator for individual age than neurocentral fusion patterns. SMA 0011 is one of very few sauropod specimens that preserves the cervico-dorsal transition in both vertebrae and ribs. The association of ribs with their respective vertebrae shows that the transition between cervical and dorsal vertebrae is significantly different in \textit{Galeamopus pabsti} than in \textit{Diplodocus carnegii} or \textit{Apatosaurus louisae}, being represented by a considerable shortening of the centra from the last cervical to the first dorsal vertebra. Diplodocids show a surprisingly high diversity in the Morrison Formation. This can possibly be explained by a combination of geographical and temporal segregation, and niche partitioning.

Tschopp, Emanuel, Friedrich A. Tschopp, and Octávio Mateus. "Overlap Indices: Tools to quantify the amount of anatomical overlap among groups of incomplete terminal taxa in phylogenetic analyses." Acta Zoologica. 99.2 (2017): 169-176. Abstracttschopp_et_al-2017-acta_zoologica_overlap_indices_tools_to_quantify_the_amount.pdfWebsite

Phylogenetic analyses of morphological data are often characterized by missing data due to incomplete operational taxonomic units, as in fossils. This incomplete knowledge derives from various reasons, including—in the case of fossils—the numerous filters an organism has to pass through during taphonomy, fossilization, weathering and collecting. Whereas several methods have been proposed to address issues raised by the inclusion of incomplete terminal taxa, until recently no tool existed to easily quantify the amount of anatomical overlap within a particular clade. The Overlap Indices provide such values and might prove useful for comparative cladistics. We herein describe these new indices and their applications in detail and provide an example file for their calculation. A case study of diplodocid sauropod dinosaurs shows how the Overlap Indices will help to explore and quantify, which one of a number of conflicting tree topologies is supported by more anatomical traits, which skeletal regions are underrepresented in a particular phylogenetic matrix, and which taxon would improve character state score completeness.

Amaral, P. "O admirável Mundo Novo do Big Data." Gazeta de Matemática. 182 (2017). Abstract
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Mateus, O., PM Callapez, and E. Puértolas-Pascual. "The oldest Crocodylia? a new eusuchian from the Late Cretaceous (Cenomanian) of Portugal." Journal of Vertebrate Paleontology, Program and Abstracts. Vol. 2017. 2017. 160. Abstract
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Mateus, O., {P. M. } Callapez, and E. Puértolas-Pascual. "The oldest Crocodylia? a new eusuchian from the Late Cretaceous (Cenomanian) of Portugal." 2017. 160. Abstract
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Correia, T., L. Barcelos, T. Nunes, D. Riff, and O. Mateus. "On a titanosaur scapula from the Marília Formation (Upper Cretaceous, Bauru Group) in Campina Verde Town." 2017. 77. Abstract
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Correia, T., L. Barcelos, T. Nunes, D. Riff, and O. Mateus. "On a titanosaur scapula from the Mar{\'ılia Formation (Upper Cretaceous, Bauru Group) in Campina Verde Town." XXV Congresso Brasileiro de Paleontologia Boletim de Resumos. 2017. 77. Abstract
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Einpaul, J., R. L. Vollum, and A. P. Ramos. "On the distribution of shear forces in non-axisymmetric slab-column connections." High Tech Concrete: Where Technology and Engineering Meet - Proceedings of the 2017 fib Symposium. 2017. 841-848. Abstract
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Tschopp, E., F. A. Tschopp, and O. Mateus. "The Overlap Index, a tool to quantify the amount of anatomical overlap among groups of incomplete terminal taxa in phylogenetic analyses." Journal of Vertebrate Paleontology, Program and Abstracts. 2017 (2017): 205-206. Abstract
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2016
Doutor, Paulo, Paula Rodrigues, Maria Ceu do Soares, and Fabio A. C. C. Chalub. "Optimal vaccination strategies and rational behaviour in seasonal epidemics." JOURNAL OF MATHEMATICAL BIOLOGY. 73 (2016): 1437-1465. Abstract

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Carepo, M. S., C. Carreira, R. Grazina, M. E. Zakrzewska, A. Dolla, C. Aubert, S. R. Pauleta, J. J. Moura, and I. Moura. "Orange protein from Desulfovibrio alaskensis G20: insights into the Mo-Cu cluster protein-assisted synthesis." J Biol Inorg Chem. 21 (2016): 53-62. AbstractWebsite

A novel metalloprotein containing a unique [S2MoS2CuS2MoS2](3-) cluster, designated as Orange Protein (ORP), was isolated for the first time from Desulfovibrio gigas, a sulphate reducer. The orp operon is conserved in almost all sequenced Desulfovibrio genomes and in other anaerobic bacteria, however, so far D. gigas ORP had been the only ORP characterized in the literature. In this work, the purification of another ORP isolated form Desulfovibrio alaskensis G20 is reported. The native protein is monomeric (12443.8 +/- 0.1 Da by ESI-MS) and contains also a MoCu cluster with characteristic absorption bands at 337 and 480 nm, assigned to S-Mo charge transfer bands. Desulfovibrio alaskensis G20 recombinant protein was obtained in the apo-form from E. coli. Cluster reconstitution studies and UV-visible titrations with tetrathiomolybdate of the apo-ORP incubated with Cu ions indicate that the cluster is incorporated in a protein metal-assisted synthetic mode and the protein favors the 2Mo:1Cu stoichiometry. In Desulfovibrio alaskensis G20, the orp genes are encoded by a polycistronic unit composed of six genes whereas in Desulfovibrio vulgaris Hildenborough the same genes are organized into two divergent operons, although the composition in genes is similar. The gene expression of ORP (Dde_3198) increased 6.6 +/- 0.5 times when molybdate was added to the growth medium but was not affected by Cu(II) addition, suggesting an involvement in molybdenum metabolism directly or indirectly in these anaerobic bacteria.

Lopes, S., and H. Rocha O jogo como promotor da comunicação e aprendizagem matemática [Games to promote communication and mathematical learning]. XXVII SIEM. Porto, Portugal: APM, 2016. Abstract

Games are commonly appointed as a methodological tool capable of promoting students’ effective learning. In this context, this study intends to analyze the impact of mathematical discussions developed while
playing a polynomial game. Namely it intends to analyze the impact on the consolidation of mathematical concepts previously worked in the classroom and on the communications skills. Two case studies where developed involving 10th grade students. Data gathering was based on direct observation and an inquiry. The main conclusions suggest that the game encouraged the discussion about the mathematical contents and therefore promoted the development of the mathematical discourse. Besides that, it allowed a deeper apprehension of mathematical concepts, and the overcome of some difficulties.

Coelho, E., and H. Rocha O raciocínio dedutivo de alunos do 10.º ano de escolaridade [The deductive reasoning of students in the 10th grade]. XXVII SIEM. Porto, Portugal: APM, 2016. Abstract

Deductive reasoning, being central in mathematics, is also usually a source of difficulties for students, more used to the empirical approaches. In this study we focus on mathematical proof and we try to give attention to how this kind of reasoning is envisaged by the students, to the options they assume when asked to develop a deductive reasoning and to the factors affecting the implementation of this kind of reasoning. The study follows a qualitative and interpretative methodological approach, including the completion of two case studies of students of the 10th grade. Data were collected in work sessions and through interviews. The main findings point to a devaluation of mathematical proof and a strong preference for empirical approaches. Yet students show ability to develop different approaches. The preference for the mathematical subject and the attention given in class to the deduction work, appears to be relevant factors when considering the students' ability to develop a deductive reasoning when involved on a mathematical proof.

Biscaia, Hugo, Noel Franco, Ricardo Nunes, and Carlos Chastre. "Old suspended timber floors flexurally-strengthened with different structural materials." Key Engineering Materials. 713 (2016): 78-81. Abstract

The design of timber beams has strict limits when it comes to the Serviceability Limit States (SLS) either in short-term or in long-term deflections. In order to face this aspect efficiently, the increase of the cross section of the beams might be considered as a solution. However, the prohibitive increase of the costs associated to this solution or the change of the initial architecturedesign of the building, opens the opportunity to find new and more efficient solutions. In that way, the use of additional reinforcements to the timber beams may be seen as a promising solution because either new or old structures would keep always their original aesthetical aspect with no significant self-weight increase and improving their behaviour to short and long-term actions.Therefore, the current study is dedicated to the analysis of composite timber beams where Fiber Reinforcement Polymers (FRP), steel or stainless steel are used to improve the stiffness, strength and deflection behaviour of old suspended timber floors. An experimental program was conducted where old suspended timber floors reinforced with CFRP strips were subjected to 4-point bending tests. A simplify nonlinear numerical model was developed to simulate the bending behaviour of the specimens and several other cases with other reinforcement configurations and different structural materials were assumed. The numerical analysis herein presented also takes into account both Ultimate and Serviceability Limit States of the reinforced specimens.

Karlovich, Alexei Yu., Yuri I. Karlovich, and Amarino B. Lebre. "On a weighted singular integral operator with shifts and slowly oscillating data." Complex Analysis and Operator Theory. 10.6 (2016): 1101-1131. AbstractWebsite

Let \(\alpha,\beta\) be orientation-preserving diffeomorphism (shifts) of \(\mathbb{R}_+=(0,\infty)\) onto itself with the only fixed points \(0\) and \(\infty\) and \(U_\alpha,U_\beta\) be the isometric shift operators on \(L^p(\mathbb{R}_+)\) given by \(U_\alpha f=(\alpha')^{1/p}(f\circ\alpha)\), \(U_\beta f=(\beta')^{1/p}(f\circ\beta)\), and \(P_2^\pm=(I\pm S_2)/2\) where \[ (S_2 f)(t):=\frac{1}{\pi i}\int\limits_0^\infty \left(\frac{t}{\tau}\right)^{1/2-1/p}\frac{f(\tau)}{\tau-t}\,d\tau, \quad t\in\mathbb{R}_+, \]
is the weighted Cauchy singular integral operator. We prove that if \(\alpha',\beta'\) and \(c,d\) are continuous on \(\mathbb{R}_+\) and slowly oscillating at \(0\) and \(\ infty\), and \[ \limsup_{t\to s}|c(t)|<1,\quad \limsup_{t\to s}|d(t)|<1, \quad s\in\{0,\infty\}, \] then the operator \((I-cU_\alpha)P_2^++(I-dU_\beta)P_2^-\) is Fredholm on \(L^p(\mathbb{R}_+)\) and its index is equal to zero. Moreover, its regularizers are described.

Fernandes, Vítor H., Preeyanuch Honyam, Teresa M. Quinteiro, and Boorapa Singha. "On semigroups of orientation-preserving transformations with restricted range." Communications in Algebra (DOI:10.1080/00927872.2014.975345). 44.1 (2016): 253-264. Abstractauthorsfinalversion.pdfWebsite

Let $X_n$ be a chain with n elements ($n\in\N$) and let $\OP_n$ be the monoid of all orientation-preserving transformations of $X_n$. In this paper, for any nonempty subset $Y$ of $X_n$, we consider the subsemigroup $\OP_n(Y)$ of $\OP_n$ of all transformations with range contained in $Y$: we describe the largest regular subsemigroup of $\OP_n(Y)$, which actually coincides with its subset of all regular elements, and Green's relations on $\OP_n(Y)$. Also, we determine when two semigroups of the type $\OP_n(Y)$ are isomorphic and calculate their ranks. Moreover, a parallel study is presented for the correspondent subsemigroups of the monoid $\OR_n$ of all either orientation-preserving or orientation-reversing transformations of $X_n$.

Brás, C. P., A. N. Iusem, and J. J. Júdice. "On the Quadratic Eigenvalue Complementarity Problem." Journal of Global Optimization, DOI: 10.1007/s10898-014-0260-5.. 66 (2016): 153-171.
Karlovich, Alexei Yu., Yuri I. Karlovich, and Amarino B. Lebre. "One-sided invertibility criteria for binomial functional operators with shift and slowly oscillating data." Mediterranean Journal of Mathematics. 13.6 (2016): 4413-4435.Website
Guerra, N. M. C., Santos C. Josefino, and Nunes A. Antão Overall stability of anchored retaining structures: revisiting Broms' method. Proceedings of the Edinburgh and Pune Workshops of TC207 of ISSMGE. Edimburgo, Escócia, 2016.
Correia, Ana, João Goes, and Pedro Barquinha Oxide TFTs on Flexible Substrates for Designing and Fabricating Analog-to-Digital Converters. 7th IFIP WG 5.5/SOCOLNET Doctoral Conference on Computing, Electrical and Industrial Systems, DoCEIS 2016. Lisbon, Portugal: IFIP WG 5.5/SOCOLNET, 2016.
Panigrahi, S., Calmeiro Martins Nunes Fortunato T. R. D. "Observation of Space Charge Dynamics Inside an All Oxide Based Solar Cell." ACS Nano. 10 (2016): 6139-6146. AbstractWebsite

The charge transfer dynamics at interfaces are fundamental to know the mechanism of photovoltaic processes. The internal potential in solar cell devices depends on the basic processes of photovoltaic effect such as charge carrier generation, separation, transport, recombination, etc. Here we report the direct observation of the surface potential depth profile over the cross-section of the ZnO nanorods/Cu2O based solar cell for two different layer thicknesses at different wavelengths of light using Kelvin probe force microscopy. The topography and phase images across the cross-section of the solar cell are also observed, where the interfaces are well-defined on the nanoscale. The potential profiling results demonstrate that under white light illumination, the photoinduced electrons in Cu2O inject into ZnO due to the interfacial electric field, which results in the large difference in surface potential between two active layers. However, under a single wavelength illumination, the charge carrier generation, separation, and transport processes between two active layers are limited, which affect the surface potential images and corresponding potential depth profile. Because of changes in the active layer thicknesses, small variations have been observed in the charge carrier transport mechanism inside the device. These results provide the clear idea about the charge carrier distribution inside the solar cell in different conditions and show the perfect illumination condition for large carrier transport in a high performance solar cell. © 2016 American Chemical Society.

Biscaia, Hugo, Noel Franco, Ricardo Nunes, and Carlos Chastre. "Old suspended timber floors flexurally-strengthened with different structural materials." 15th International Conference on Fracture and Damage Mechanics. Ed. Andrés Sáez Ferri Aliabadi M. H. Jesús Toribio, Vladislav Mantič. Alicante, Spain 2016. Abstract

The design of timber beams has strict limits when it comes to the Serviceability Limit States (SLS) either in short-term or in long-term deflections. In order to face this aspect efficiently, the increase of the cross section of the beams might be considered as a solution. However, the prohibitive increase of the costs associated to this solution or the change of the initial architecturedesign of the building, opens the opportunity to find new and more efficient solutions. In that way, the use of additional reinforcements to the timber beams may be seen as a promising solution because either new or old structures would keep always their original aesthetical aspect with no significant self-weight increase and improving their behaviour to short and long-term actions.Therefore, the current study is dedicated to the analysis of composite timber beams where Fiber Reinforcement Polymers (FRP), steel or stainless steel are used to improve the stiffness, strength and deflection behaviour of old suspended timber floors. An experimental program was conducted where old suspended timber floors reinforced with CFRP strips were subjected to 4-point bending tests. A simplify nonlinear numerical model was developed to simulate the bending behaviour of the specimens and several other cases with other reinforcement configurations and different structural materials were assumed. The numerical analysis herein presented also takes into account both Ultimate and Serviceability Limit States of the reinforced specimens.

Salmerón, J. M. G., P. Amaral, L. G. Casado, E. M. T. Hendrix, and J. Żilinskas. "On Regular Simplex Refinement in Copositivity Detection." XIII global optimization workshop GOW2016 4-8 September 2016. 2016. 163-166. Abstract
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Esquível, Manuel L., Pedro P. Mota, and João Tiago Mexia. "On some statistical models with a random number of observations." Journal of Statistical Theory and Practice. 10 (2016): 805-823. AbstractWebsite

We extend some classical statistical inference to the case of a random number of observations with a stabilized distribution: namely, in the normal model, inference for the mean with known and unknown variance and inference for the variance. We describe some useful models for the number of observations obtained by truncation or translation of usual models given by integer-valued random variables: Poisson, binomial, geometric, and negative binomial. We present an efficient random search algorithm for the computation of the quantiles of the relevant statistics, we describe an interval estimation procedure for the extended model, and we propose a parametric bootstrap simulation study to validate the proposed procedure.