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2013
Coelho, Carlos A., and Filipe J. Marques. "The Multi-Sample Block-Scalar Sphericity Test: Exact and near-exact distributions for its likelihood ratio test statistic." Communications in Statistics-Theory and Methods. 42 (2013): 1153-1175. Abstract
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Marques, Filipe J., and Carlos A. Coelho. "The multisample block-diagonal equicorrelation and equivariance test." AIP Conference Proceedings. Vol. 1558. AIP, 2013. 793-796. Abstract
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Coelho, Carlos A., and Filipe J. Marques. "Near-exact distributions for the block equicorrelation and equivariance likelihood ratio test statistic." AIP Conference Proceedings. Vol. 1557. AIP, 2013. 429-433. Abstract
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Dell'acqua, S., S. R. Pauleta, I. Moura, and JJG Moura. "Nitrous oxide reductase." Encyclopedia of Metalloproteins. Eds. R. H. Kretsinger, V. N. Uversky, and E. A. Permyakov. Springer, 2013. Abstract
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Kasthurirangan, S., J. K. Saha, A. N. Agnihotri, S. Bhattacharyya, D. Misra, A. Kumar, P. K. Mukherjee, J. P. Santos, A. M. Costa, P. Indelicato, T. K. Mukherjee, and L. C. Tribedi. "Observation of 2p3 d (1Po)→ 1s3d (1De) Radiative Transition in He-like Si, S, and Cl Ions." Physical Review Letters. 111 (2013): 243201. AbstractWebsite
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Kasthurirangan, S., J. K. Saha, A. N. Agnihotri, S. Bhattacharyya, D. Misra, A. Kumar, P. K. Mukherjee, J. P. Santos, A. M. Costa, P. Indelicato, T. K. Mukherjee, and L. C. Tribedi. "Observation of 2p3 d (1Po)→ 1s3d (1De) Radiative Transition in He-like Si, S, and Cl Ions." Physical Review Letters. 111 (2013): 243201. AbstractWebsite
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Mota, Pedro. "On a Continuous-Time Stock Price Model with Two Mean Reverting Regimes." Advances in Regression, Survival Analysis, Extreme Values, Markov Processes and Other Statistical Applications. Eds. João Lita da Silva, Frederico Caeiro, Isabel Natário, and Carlos A. Braumann. Berlin, Heidelberg: Springer Berlin Heidelberg, 2013. 297-305. Abstract

Motivated by the need to describe regime switching in stock prices, we introduce and study a stochastic process in continuous time with two regimes and one threshold driving the change in regimes. When the difference between the regimes is simply given by different sets of real-valued parameters for the drift and diffusion coefficients, we show that there are consistent estimators for the threshold as long as we know how to classify a given observation of the process as belonging to one of the two regimes.

Elisa, M., B. A. Sava, I. C. Vasiliu, R. C. C. Monteiro, JP Veiga, L. Ghervase, I. Feraru, and R. Iordanescu. "Optical and structural characterization of samarium and europium-doped phosphate glasses." Journal of Non-Crystalline Solids. 369 (2013): 55-60. Abstract
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Elisa, M. a, B. A. a Sava, I. C. a Vasiliu, R. C. C. b Monteiro, J. P. B. Veiga, L. a Ghervase, I. a Feraru, and R. a Iordanescu. "Optical and structural characterization of samarium and europium-doped phosphate glasses." Journal of Non-Crystalline Solids. 369 (2013): 55-60. AbstractWebsite

The work deals with optical and structural properties of aluminophosphate glasses from Li2O-BaO-Al2O3-La 2O3-P2O5 system containing Sm 3 + and Eu3 + ions. X-ray fluorescence (XRF) has been used to establish the elemental composition of these materials. The influence of Sm3 + and Eu3 + ions on the optical properties of these glasses has been investigated in relation with their structural characteristics. The optical behavior of these materials has been studied by ultra-violet-visible (UV-Vis) spectroscopy, revealing absorption maxima specific to the doping ions. Structural information via vibration modes was provided by Fourier Transform Infrared (FTIR) absorption spectra evidenced as POP symmetrical and asymmetrical stretching vibration modes, POP bend, PO 2- symmetrical and asymmetrical stretching vibration modes, PO stretching vibration mode and POH water absorbance. Raman spectra acquired by 514.5 nm laser excitation disclosed peaks specific to metaphosphate network. Information about the elemental compositional homogeneity of Sm 3 + and Eu3 +-containing glasses as well as about the defects of the doped-glasses is revealed by scanning electron microscopy/energy dispersive spectrometry (SEM/EDS). Fluorescence spectroscopy measurements put in evidence important fluorescence peaks found at 596 nm and 643 nm for Sm 3 + ions in phosphate matrix and 611 nm and 700 nm in the case of Eu3 +-doped glass. © 2013 Elsevier B.V.

Elisa, M., B. A. Sava, I. C. Vasiliu, R. C. C. Monteiro, JP Veiga, L. Ghervase, I. Feraru, and R. Iordanescu. "Optical and structural characterization of samarium and europium-doped phosphate glasses." Journal of Non-Crystalline Solids. 369 (2013): 55-60. Abstract
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Mannion, PD, P. Upchurch, RN Barnes, and O. Mateus. "Osteology of the Late Jurassic Portuguese sauropod dinosaur Lusotitan atalaiensis (Macronaria) and the evolutionary history of basal titanosauriforms." Zoological Journal of the Linnean Society. 168 (2013): 98-206. Abstract
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Martins, R.a, Pereira Fortunato L. b E. c. "Paper electronics: A challenge for the future." Digest of Technical Papers - SID International Symposium. Vol. 44. 2013. 365-367. Abstract

In this paper we report results concerning the use of paper as substrate and as an electronic component for the next generation of sustainable low cost electronic systems, where different examples of applications are given. © 2013 Society for Information Display.

Sava, B. A. a, M. a Elisa, L. b Boroica, and R. C. C. c Monteiro. "Preparation method and thermal properties of samarium and europium-doped alumino-phosphate glasses." Materials Science and Engineering B: Solid-State Materials for Advanced Technology. 178 (2013): 1429-1435. AbstractWebsite

The present work investigates alumino-phosphate glasses from Li 2O-BaO-Al2O3-La2O3-P 2O5 system containing Sm3+ and Eu3+ ions, prepared by two different ways: a wet raw materials mixing route followed by evaporation and melt-quenching, and by remelting of shards. The linear thermal expansion coefficient measured by dilatometry is identical for both rare-earth-doped phosphate glasses. Comparatively to undoped phosphate glass the linear thermal expansion coefficient increases with 2 × 10-7 K-1 when dopants are added. The characteristic temperatures very slowly decrease but can be considered constant with atomic weight, atomic number and f electrons number of the doping ions in the case of Tg (vitreous transition temperature) and Tsr (high annealing temperature) but slowly increase in the case of Tir (low annealing temperature-strain point) and very slowly increase, being practically constant in the case of TD (dilatometric softening temperature). Comparatively to undoped phosphate glass the characteristic temperatures of Sm and Eu-doped glasses present lower values. The higher values of electrical conductance for both doped glasses, comparatively to usual soda-lime-silicate glass, indicate a slightly reduced stability against water. The viscosity measurements, showed a quasi-linear variation with temperature the mean square deviation (R 2) being ranged between 0.872% and 0.996%. The viscosity of doped glasses comparatively to the undoped one is lower at the same temperature. Thermogravimetric analysis did not show notable mass change for any of doped samples. DSC curves for both rare-earth-doped phosphate glasses, as bulk and powdered samples, showed Tg values in the range 435-450 C. Bulk samples exhibited a very weak exothermic peak at about 685 C, while powdered samples showed two weak exothermic peaks at about 555 C and 685 C due to devitrification of the glasses. Using designed melting and annealing programs, the doped glasses were improved regarding bubbles and cords content and strain elimination. © 2013 Elsevier B.V. All rights reserved.

Maneira, António, and João Correia de Freitas. "Projetos de v{\'ıdeos interativos no ensino superior: multimédia semântico e a aprendizagem." III Colóquio Luso-Brasileiro de Educação a Distância e Elearning. http://lead.uab.pt/OCS/index.php/CLB/club/paper/view/173, 2013. Abstract
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Maiti, Biplab K., Teresa Avilés, Marta S. P. Carepo, Isabel Moura, Sofia R. Pauleta, and José J. G. Moura. "Rearrangement of Mo-Cu-S Cluster Reflects the Structural ­Instability of Orange Protein Cofactor." Zeitschrift für anorganische und allgemeine Chemie. 639 (2013): 1361-1364. AbstractWebsite
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Martins, R.F.P.a, Ahnood Correia Pereira Barros Barquinha Costa Ferreira Nathan Fortunato A. b N. a. "Recyclable, flexible, low-power oxide electronics." Advanced Functional Materials. 23 (2013): 2153-2161. AbstractWebsite

The ability to process and dimensionally scale field-effect transistors with and on paper and to integrate them as a core component for low-power-consumption analog and digital circuits is demonstrated. Low-temperature-processed p- and n-channel integrated oxide thin-film transistors in the complementary metal oxide semiconductor (CMOS) inverter architecture are seamlessly layered on mechanically flexible, low-cost, recyclable paper substrates. The possibility of building these circuits using low-temperature processes opens the door to new applications ranging from smart labels and sensors on clothing and packaging to electronic displays printed on paper pages for use in newspapers, magazines, books, signs, and advertising billboards. Because the CMOS circuits reported constitute fundamental building blocks for analog and digital electronics, this development creates the potential to have flexible form factor computers seamlessly layered onto paper. The holistic approach of merging low-power circuitry with a recyclable substrate is an important step towards greener electronics. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Szabo, Csilla I., Pedro Amaro, Mauro Guerra, Sophie Schlesser, Alexander Gumberidze, Jose Paulo Santos, and Paul Indelicato. "Reference free, high-precision measurements of transition energies in few electron argon ions." AIP APPLICATION OF ACCELERATORS IN RESEARCH AND INDUSTRY: Twenty-Second International Conference. 1525 (2013): 68-72. AbstractWebsite

The use of a vacuum double crystal spectrometer, coupled to an electron-cyclotron resonance ion source (ECRIS), allows to measure low-energy x-ray transitions energies in highly-charged ions with accuracies of the order of a few parts per million. We have used this installation to measure the 1s2p 1 P1 - 1s2 1 S0 diagram line and the 1s2s 3 S1 - 1s2 1 S0 forbidden M1 transition energies in helium-like argon, the 1s2s2p 2 P j 1s2 2s 2 S1/2 transitions in lithium-like argon and the 1s2s2 2p 1 P1 - 1s2 2s2 1 S0 transition in beryllium-like argon. These transition measurements have accuracies between 2 and 4 ppm depending on the line intensity. Thanks to the excellent agreement between the simulations and the measurements, we were also able to measure the transition width of all the allowed transitions. The results are compared to recent QED and relativistic many-body calculations.

Szabo, Csilla I., Pedro Amaro, Mauro Guerra, Sophie Schlesser, Alexander Gumberidze, Jose Paulo Santos, and Paul Indelicato. "Reference free, high-precision measurements of transition energies in few electron argon ions." AIP Conf. Proc.. 1525 (2013): 68-72. AbstractWebsite

The use of a vacuum double crystal spectrometer, coupled to an electron-cyclotron resonance ion source (ECRIS), allows to measure low-energy x-ray transitions energies in highly-charged ions with accuracies of the order of a few parts per million. We have used this installation to measure the 1s2p 1 P1 - 1s2 1 S0 diagram line and the 1s2s 3 S1 - 1s2 1 S0 forbidden M1 transition energies in helium-like argon, the 1s2s2p 2 P j 1s2 2s 2 S1/2 transitions in lithium-like argon and the 1s2s2 2p 1 P1 - 1s2 2s2 1 S0 transition in beryllium-like argon. These transition measurements have accuracies between 2 and 4 ppm depending on the line intensity. Thanks to the excellent agreement between the simulations and the measurements, we were also able to measure the transition width of all the allowed transitions. The results are compared to recent QED and relativistic many-body calculations.

Aguiar, F. C., J. O. Cerdeira, M. J. Martins, and M. T. Ferreira. "Riparian forests of Southwest Europe: Are functional trait and species composition assemblages constrained by environment?" Journal of Vegetation Science. 24 (2013): 628-638. Abstract
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Araújo, Andreia, Raquel Barros, Tiago Mateus, Diana Gaspar, Nuno Neves, António Vicente, Sergej A. Filonovich, Pedro Barquinha, Elvira Fortunato, Ana M. Ferraria, and others. "Role of a disperse carbon interlayer on the performances of tandem a-Si solar cells." Science and Technology of Advanced Materials. 14 (2013): 045009. Abstract
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Ercin, G. H., P. P. Camanho, J. Xavier, G. Catalanotti, S. Mahdi, and P. Linde. "Size effects on the tensile and compressive failure of notched composite laminates." Composite Structures. 96 (2013): 736-744. Abstract
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Viegas, Aldino, Joao Sardinha, Filipe Freire, Daniel F. Duarte, Ana L. Carvalho, Carlos M. G. A. Fontes, Maria J. Romao, Anjos L. Macedo, and Eurico J. Cabrita. "Solution structure, dynamics and binding studies of a family 11 carbohydrate-binding module from Clostridium thermocellum (CtCBM11)." The Biochemical journal. 451 (2013): 289-300.Website
Santos, R., J. Loureiro, A. Nogueira, E. Elangovan, JV Pinto, JP Veiga, T. Busani, E. Fortunato, R. Martins, and I. Ferreira. "Thermoelectric properties of V2O5 thin films deposited by thermal evaporation." Applied Surface Science. 282 (2013): 590-594. Abstract
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