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2014
Moura, I., C. Carreira, S. Pauleta, R. F. Nunes, J. J. Moura, S. Ramos, S. Dell'acqua, and O. Einsle. "INSIGHTS INTO THE CATALYTICCYCLE OF Pseudomonas nautica NITROUS OXIDE REDUCTASE." Journal of Biological Inorganic Chemistry. Vol. 19. J Biol Inorg Chem, 19. 2014. S104. Abstract
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Gaspar, D., S. N. Fernandes, G. dea Oliveira, J. G. Fernandes, P. Grey, R. V. Pontes, L. Pereira, R. Martins, M. H. Godinho, and E. Fortunato. "{Nanocrystalline cellulose applied simultaneously as the gate dielectric and the substrate in flexible field effect transistors.}." Nanotechnology. 25 (2014): 094008. AbstractWebsite

Cotton-based nanocrystalline cellulose (NCC), also known as nanopaper, one of the major sources of renewable materials, is a promising substrate and component for producing low cost fully recyclable flexible paper electronic devices and systems due to its properties (lightweight, stiffness, non-toxicity, transparency, low thermal expansion, gas impermeability and improved mechanical properties).Here, we have demonstrated for the first time a thin transparent nanopaper-based field effect transistor (FET) where NCC is simultaneously used as the substrate and as the gate dielectric layer in an 'interstrate' structure, since the device is built on both sides of the NCC films; while the active channel layer is based on oxide amorphous semiconductors, the gate electrode is based on a transparent conductive oxide.Such hybrid FETs present excellent operating characteristics such as high channel saturation mobility (>7 cm(2) V (-1) s(-1)), drain-source current on/off modulation ratio higher than 10(5), enhancement n-type operation and subthreshold gate voltage swing of 2.11 V/decade. The NCC film FET characteristics have been measured in air ambient conditions and present good stability, after two weeks of being processed, without any type of encapsulation or passivation layer. The results obtained are comparable to ones produced for conventional cellulose paper, marking this out as a promising approach for attaining high-performance disposable electronics such as paper displays, smart labels, smart packaging, RFID (radio-frequency identification) and point-of-care systems for self-analysis in bioscience applications, among others.

Miguel, Catarina, Joana V. Pinto, Mark Clarke, and Maria J. Melo. "{The alchemy of red mercury sulphide: The production of vermilion for medieval art}." Dyes and Pigments. 102 (2014): 210-217. AbstractWebsite

abstract Vermilion red, mercury sulphide (a-HgS), was one of the most important reds in art and its use as a pigment dates back to Antiquity. In medieval Europe, it could be mined as cinnabar, or produced as vermilion by heating mercury with sulphur. This work aims to study the production of synthetic vermilion as a medieval pigment and to confirm which was the source (mineral or artificial) of the reds used in Portuguese medieval illuminations. The production of synthetic vermilion was based on the process described in the Judaeo-Portuguese medieval treatise “The book on how to make colours”, using materials and technologies as close as possible to the medieval ones. The reaction mechanism was studied by following the heating process by X-ray diffraction, and it was possible to conclude that the transformation from black cubic b-HgS into red hexagonal a-HgS is a solid-state phase transition, occurring at 235 ?C. This result is contrary to what published in technical art literature, in which this process is described as a sublimation. Moreover, Scanning Electron Microscopy evidenced a sinterization effect on the artificial vermilion, not found in medieval original samples nor in paints prepared with mineral cinnabar from Almadén (Spain). Red mercury sulphide, natural and synthetic,was then prepared as a parchment-glue paint and compared to proteinaceous red paints from 12the13th century minia- tures produced in important medieval monasteries, previously fully characterized by a multi-analytical approach (m-Energy dispersive X-ray fluorescence, m-Fourier Transform Infrared Spectroscopy, Raman microscopy). A comparative Electron probe microanalysis of the red paints point to amineral provenance for medieval vermilion found in Portuguese illuminations

Lúcio, Válter, and Carlos Chastre. "Precast concrete wind tower structures. Historic development, current development and future potential." CPI - Concrete Plant International, 3 (2014): 110-115. Abstractcpi_03-2014_p144-149.pdfWebsite

The wind energy production is a growing industry and the energy produced is renewable and environmentally cleaner than most of the energy production systems. The supports of the wind energy generators may be built with precast concrete elements. The precast solutions for these structures are competitive in comparison to other structural systems. The evolution of the technology for wind energy production shows a clear need for larger wind turbines and longer blades and, consequently, taller towers. The experience also shows that precast concrete solutions increase their competitiveness as the tower height increases. Offshore wind farms have some advantages in relation to onshore ones, which explains recent investments in this area. Also in this case, the durability of concrete in the sea when compared to steel, gives advantages to precast concrete in relation to other structural solutions. This paper shows the evolution of the supports of the wind energy generators and the advantages of the use of precast concrete towers.

Rahangdale, H. V., M. Guerra, P. K. Das, S. De, J. P. Santos, D. Mitra, and S. Saha. "Determination of subshell-resolved <span class="aps-inline-formula"><math><mi>L</mi></math></span>-shell-ionization cross sections of gold induced by 15–40-keV electrons." Physical Review A. 89 (2014): 052708. AbstractWebsite
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Amaro, P., C. I. Szabo, S. Schlesser, A. Gumberidze, E. G. Kessler, A. Henins, E. O. Le Bigot, M. Trassinelli, J. M. Isac, P. Travers, M. Guerra, J. P. Santos, and P. Indelicato. "A vacuum double-crystal spectrometer for reference-free X-ray spectroscopy of highly charged ions." Radiation Physics and Chemistry. 98 (2014): 132-149. AbstractWebsite

Radiation Physics and Chemistry, 98 + (2014) 132-149. doi:10.1016/j.radphyschem.2014.01.015

Carepo, M. S., S. R. Pauleta, A. G. Wedd, J. J. Moura, and I. Moura. "Mo-Cu metal cluster formation and binding in an orange protein isolated from Desulfovibrio gigas." J Biol Inorg Chem. 19 (2014): 605-14. AbstractWebsite

The orange protein (ORP) isolated from the sulfate-reducing bacterium Desulfovibrio gigas (11.8 kDa) contains a mixed-metal sulfide cluster of the type [S2MoS2CuS2MoS2](3-) noncovalently bound to the polypeptide chain. The D. gigas ORP was heterologously produced in Escherichia coli in the apo form. Different strategies were used to reconstitute the metal cluster into apo-ORP and obtain insights into the metal cluster synthesis: (1) incorporation of a synthesized inorganic analogue of the native metal cluster and (2) the in situ synthesis of the metal cluster on the addition to apo-ORP of copper chloride and tetrathiomolybdate or tetrathiotungstate. This latter procedure was successful, and the visible spectrum of the Mo-Cu reconstituted ORP is identical to the one reported for the native protein with absorption maxima at 340 and 480 nm. The (1)H-(15)N heteronuclear single quantum coherence spectra of the reconstituted ORP obtained by strategy 2, in contrast to strategy 1, exhibited large changes, which required sequential assignment in order to identify, by chemical shift differences, the residues affected by the incorporation of the cluster, which is stabilized inside the protein by both electrostatic and hydrophobic interactions.

Altstadt, S. G., et al. "{$^{13,14}$B(n, $\gamma$) via Coulomb Dissociation for Nucleosynthesis towards the r-Process}." Nuclear Data Sheets. 120 (2014): 197-200. AbstractWebsite
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Cunha, Jácome, João Paulo Fernandes, Jorge Mendes, Rui Pereira, and João Saraiva. "Design and Implementation of Queries for Model-Driven Spreadsheets." Central European Functional Programming School - 5th Summer School, CEFP 2013, Revised Selected Papers. Eds. Viktória Zsók, and et al. Lecture Notes in Computer Science. Heidelberg: Springer, 2014. Abstractdsl13_query.pdf

This paper presents a domain-specific querying language for model-driven spreadsheets. We briefly show the design of the language and present in detail its implementation, from the denormalization of data and translation of our user-friendly query language to a more efficient query, to the execution of the query using Google. To validate our work, we executed an empirical study, comparing QuerySheet with an alternative spreadsheet querying tool, which produced positive results.

Cunha, Jácome, João Paulo Fernandes, and João Saraiva. "Spreadsheet Engineering." Central European Functional Programming School - 5th Summer School, CEFP 2013, Revised Selected Papers. Eds. Viktória Zsók, and et al. Lecture Notes in Computer Science. Springer, Heidelberg 2014. Abstractdsl13_notes.pdf

These tutorial notes present a methodology for spreadsheet engineering. First, we present data mining and database techniques to reason about spreadsheet data. These techniques are used to compute relationships between spreadsheet elements (cells/columns/rows). These relations are then used to infer a model defining the business logic of the spreadsheet. Such a model of a spreadsheet data is a visual domain specific language that we embed in a well-known spreadsheet system. The embedded model is the building block to define techniques for model-driven spreadsheet development, where advanced techniques are used to guarantee the model-instance synchronization. In this model-driven environment, any user data update as to follow the the model-instance conformance relation, thus, guiding spreadsheet users to introduce correct data. Data refinement techniques are used to synchronize models and instances after users update/evolve the model. These notes briefly describe our model-driven spreadsheet environment, the MDSheet environment, that implements the presented methodology. To evaluate both proposed techniques and the MDSheet tool, we have conducted, in laboratory sessions, an empirical study with the summer school participants. The results of this study are presented in these notes.

Safari, L., P. Amaro, J. P. Santos, and F. Fratini. "Angular and polarization analysis for two-photon decay of <span class="aps-inline-formula"><math xmlns="http://www.w3.org/1998/Math/MathML"><mrow><mn>2</mn><mi>s</mi></mrow></math>&." Physical Review A. 90 (2014): 014502. AbstractWebsite

The amplitude of two-photon transitions between hyperfine states in hydrogenlike ions is derived based on the relativistic Dirac equation and second-order perturbation theory. We study angular and linear polarization properties of the photon pair emitted in the decay of $2s$ states, where spin-flip and non-spin-flip transitions are highlighted. We pay particular attention to hydrogenlike uranium, since it is an ideal candidate for investigating relativistic and high-multipole effects, such as spin-flip transitions. Two types of emission patterns are identified: (i) non-spin-flip transitions are found to be characterized by an angular distribution of the type $W($\theta${})$\sim${}1+{cos}^{2}$\theta${}$ while the polarizations of the emitted photons are parallel; and (ii) spin-flip transitions have somewhat smaller decay rates and are found to be characterized by an angular distribution of the type $W($\theta${})$\sim${}1$-${}1/3{cos}^{2}$\theta${}$ while the polarizations of the emitted photons are orthogonal, where $$\theta${}$ is the angle between photons directions. Deviations due to nondipole and relativistic contributions are evaluated for both types of transitions. This work is the first step toward exploring the effect of the nucleus over the angular and polarization properties of the photon pairs emitted by two-photon transitions.

Safari, L., P. Amaro, J. P. Santos, and F. Fratini. "Angular and polarization analysis for two-photon decay of <span class="aps-inline-formula"><math xmlns="http://www.w3.org/1998/Math/MathML"><mrow><mn>2</mn><mi>s</mi></mrow></math>&." Physical Review A. 90 (2014): 014502. AbstractWebsite

The amplitude of two-photon transitions between hyperfine states in hydrogenlike ions is derived based on the relativistic Dirac equation and second-order perturbation theory. We study angular and linear polarization properties of the photon pair emitted in the decay of $2s$ states, where spin-flip and non-spin-flip transitions are highlighted. We pay particular attention to hydrogenlike uranium, since it is an ideal candidate for investigating relativistic and high-multipole effects, such as spin-flip transitions. Two types of emission patterns are identified: (i) non-spin-flip transitions are found to be characterized by an angular distribution of the type $W($\theta${})$\sim${}1+{cos}^{2}$\theta${}$ while the polarizations of the emitted photons are parallel; and (ii) spin-flip transitions have somewhat smaller decay rates and are found to be characterized by an angular distribution of the type $W($\theta${})$\sim${}1$-${}1/3{cos}^{2}$\theta${}$ while the polarizations of the emitted photons are orthogonal, where $$\theta${}$ is the angle between photons directions. Deviations due to nondipole and relativistic contributions are evaluated for both types of transitions. This work is the first step toward exploring the effect of the nucleus over the angular and polarization properties of the photon pairs emitted by two-photon transitions.

Fratini, F., L. Safari, A. G. Hayrapetyan, K. Jankala, P. Amaro, and J. P. Santos. "Quantized form factor shift in the presence of free electron laser radiation." EPL (Europhysics Letters). 107 (2014): 13002. AbstractWebsite

In electron scattering, the target form factors contribute significantly to the diffraction pattern and carry information on the target electromagnetic charge distribution. Here we show that the presence of electromagnetic radiation, as intense as currently available in free electron lasers, shifts the dependence of the target form factors by a quantity that depends on the number of photons absorbed or emitted by the electron as well as on the parameters of the electromagnetic radiation. As example, we show the impact of intense ultraviolet and soft X-ray radiation on elastic electron scattering by the Ne-like argon ion and by the xenon atom. We find that the shift brought by the radiation to the form factor is of the order of some percent. Our results may open up a new avenue to explore matter with the assistance of laser.

Fratini, F., L. Safari, A. G. Hayrapetyan, K. Jankala, P. Amaro, and J. P. Santos. "Quantized form factor shift in the presence of free electron laser radiation." EPL (Europhysics Letters). 107 (2014): 13002. AbstractWebsite

In electron scattering, the target form factors contribute significantly to the diffraction pattern and carry information on the target electromagnetic charge distribution. Here we show that the presence of electromagnetic radiation, as intense as currently available in free electron lasers, shifts the dependence of the target form factors by a quantity that depends on the number of photons absorbed or emitted by the electron as well as on the parameters of the electromagnetic radiation. As example, we show the impact of intense ultraviolet and soft X-ray radiation on elastic electron scattering by the Ne-like argon ion and by the xenon atom. We find that the shift brought by the radiation to the form factor is of the order of some percent. Our results may open up a new avenue to explore matter with the assistance of laser.

Maiti, B. K., T. Aviles, I. Moura, S. R. Pauleta, and JJG Moura. "Synthesis and characterization of [S2MoS2Cu(n-SPhF)](2-) (n = o, m, P) clusters: Potential F-19-NMR structural probes for Orange Protein." Inorg Chem Commun. 45 (2014): 97-100. AbstractWebsite

Three fluorinated Mo-Cu-thiolate isomers,[Ph4Ph[S2MoS2Cu(n-SPhF)], [n-SPhF = 2-fluorothiophenol (la)], 3-fluorothiophenol (lb), and 4-fluorothiophenol (1c)] were synthesized and spectroscopically characterized. The F-19-NMR signal of the fluorine atom in the.benzene has different chemical shift for each isomer, which is highly influenced by the local environment that can be manipulated by different solvents and solutes. The fluorine-19 chemical shift is an advantageous NMR structural probe in alternative to H-1-NMR [B.K. Maiti, T. Aviles, M. Matzapetakis, I. Moura, S.R. Pauleta, JJ.G. Moura, Eur. J. Inorg. Chem. (2012) 4159.], that can be used to provide local information on the pocket of the metal cluster in the Orange Protein (ORP). (C) 2014 Elsevier B.V. All rights reserved.

Saponaro, A. C., M. Matzapetakis, B. Santoro, S. R. Pauleta, and A. Moroni. "The Auxiliary Subunit TRIP8B Inhibits the Binding of CAMP to HCN2 Channels Through an Allosteric Mechanism." Biophysical Journal. Vol. 106. Biophys J, 106. 2014. 758a. Abstract
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Johnston, E. M., S. Dell'acqua, S. Ramos, S. R. Pauleta, I. Moura, and E. I. Solomon. "Determination of the active form of the tetranuclear copper sulfur cluster in nitrous oxide reductase." J Am Chem Soc. 136 (2014): 614-7. AbstractWebsite

N2OR has been found to have two structural forms of its tetranuclear copper active site, the 4CuS Cu(Z)* form and the 4Cu2S Cu(Z) form. EPR, resonance Raman, and MCD spectroscopies have been used to determine the redox states of these sites under different reductant conditions, showing that the Cu(Z)* site accesses the 1-hole and fully reduced redox states, while the Cu(Z) site accesses the 2-hole and 1-hole redox states. Single-turnover reactions of N2OR for Cu(Z) and Cu(Z)* poised in these redox states and steady-state turnover assays with different proportions of Cu(Z) and Cu(Z)* show that only fully reduced Cu(Z)* is catalytically competent in rapid turnover with N2O.

Espadinha-Cruz, Pedro, António Gonçalves-Coelho, António Mourão, and António Grilo. "Business Interoperability: Dyadic supply chain process decomposition using Axiomatic Design." 2014. 93-100. Abstract
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JP, Borges, Canejo JP, Fernandes SN, Brogueira P, and GODINHO MH. "Cellulose‐Based Liquid Crystalline Composite Systems." Nanocellulose Polymer Nanocomposites: Fundamentals and Applications. Ed. Vijay Kumar Thakur. Scrivener Publishing - Wiley. Scrivener Publishing - Wiley, 2014. 215-235. Abstract
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Azevedo, S. G., S., Carvalho, H., H., Cruz-Machado, and V. "A cross case analysis of RFID deployment Fast Fashion Supply Chain." Advances in Intelligent Systems and Computing. 2014. 45-57. Abstract
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Joaquim, Castro-Fonseca, and Grilo António. "A DEA Application for Hotels Facebook Posting." 2014. Abstract
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K., Chantarachalee, Carvalho, H., H., Cruz-Machado, and V. "Designing lean supply chains a case study." Advances in Intelligent Systems and Computing. 2014. 45-57. Abstract
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Aneesh, Zutshi, Grilo António, and Jardim-Gonçalves Ricardo. "A Dynamic Agent-Based Modeling Framework for Digital Business Models: Applications to Facebook and a Popular Portuguese Online Classifieds Website." Advances in Intelligent Systems and Computing. 2014. 105-117. Abstract
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Aneesh, Zutshi, Grilo Antonio, and Jardim-Gonçalves Ricardo. "DYNAMOD—An Agent Based Modeling Framework: Applications to Online Social Networks." Advances in Intelligent Systems and Computing. 2014. 349-361. Abstract
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