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2011
Valtchev, Stanimir. "Medium concentration system HSUN: demonstration results and application of diverse silicon cells." 26th European Photovoltaic Solar Energy Conference and Exhibition (PVSEC). 2011. Abstract
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Alves, M., P. Chicau, H. Matias, J. Passarinho, C. Pinheiro, and C. P. Ricardo. "Metabolic analysis revealed altered amino acid profiles in Lupinus albus organs as a result of boron deficiency." Physiologia Plantarum. 142 (2011): 224-232. AbstractWebsite

We analysed the changes in the metabolites of Lupinus albus organs (leaf-blades, petioles, apexes, hypocotyls and roots) as a consequence of B deficiency. The deficiency did not affect malate concentration and induced only minor changes in the sugar content, suggesting that the carbohydrate metabolism is little affected by the deficiency. Contrarily, marked changes in the content of free amino acids were observed, with some specific variations associated with the different organs. These changes indicate that various aspects of metabolism implicated in the amino acid accumulation were affected by B deficiency. Most of the detected changes appear to have implications with some stress responses or signalling processes. Asparagine and proline that increase in many stresses also accumulated in petioles, apexes and hypocotyls. Accumulation of gamma-aminobutyric acid shunt amino acids, indicative of production of reactive oxygen species, occurs in the same three organs and also the roots. The increase in the branched-chain amino acids, observed in all organs, suggests the involvement of B with the cytoskeleton, whereas glycine decrease in leaf-blades and active growing organs (apexes and roots) could be associated with the proposed role of this amino acids in plant signalling in processes that might be associated with the decreased growth rates observed in B deficiency. Despite the admitted importance of free amino acids in plant metabolism, the available information on this matter is scarce. So our results bring new information concerning the effects of B deficiency in the metabolism of the several L. albus organs.

Alves, M., P. Chicau, H. Matias, J. Passarinho, C. Pinheiro, and C. P. Ricardo. "Metabolic analysis revealed altered amino acid profiles in Lupinus albus organs as a result of boron deficiency." Physiologia Plantarum. 142 (2011): 224-232. AbstractWebsite
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Águas, H., I. Bernacka-Wojcik, T. Busani, E. Fortunato, R. Martins, P. Lopes, P. Simões, M. Ferreira, and L. Hilliou. "Microplat project: development status." III Annual Meeting of the I3N–Institute of Nanostructures, Nanomodelling and Nanofabrication, 2011. 2011. 9. Abstract
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Araújo, João, Michael Kinyon, and Janusz Konieczny. "Minimal paths in the commuting graphs of semigroups." European J. Combin.. 32 (2011): 178-197. AbstractWebsite
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Silva, Tiago A. N., and M. A. R. Loja Minimization of Thermal Residual Stresses on Functionally Graded Sandwich Structures Using Differential Evolution. Eds. Marques V. A Madureira C. Reis. 2nd International Symposium on Computational Intelligence for Engineering Systems (ISCIES 2011)., 2011. Abstract
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Gil, P., A. Paulo, L. Palma, A. Santos, and Alberto Cardoso. "Model Based Predictive Control over Wireless Sensor and Actuator Networks." The 37th Annual Conference of the IEEE Industrial Electronics Society (IECON 2011). n/a 2011. Abstract
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Gomes, Maria Isabel, Ana Paula Barbosa-povoa, and Augusto Q. Novais. "Modelling a recovery network for WEEE: A case study in Portugal." Waste Management. 31 (2011): 1645-1660. AbstractWebsite

The European Union directive for electric and electronic waste, published in 2003, enforced all European countries to meet some targets concerning the recycling and recovery of these products. This directive was transposed to the Portuguese legislation in 2004. Following this, a group of EEE producers set up an organization (Amb3e) whose mission was to design and manage a nationwide recovery network for WEEE, which will be the subject matter of this work. A generic MILP model is proposed to represent this network, which is applied to its design and planning, where the best locations for collection and sorting centres are chosen simultaneously with the definition of a tactical network planning. Several analyses are performed to provide further insights regarding the selection of these alternative locations. The results gave support to the company strategic expansion plans for a high number of centres to be opened and to their location near the major WEEE sources.

Guerra, M., F. Parente, P. Indelicato, and J. P. Santos. "Modified binary encounter Bethe model for electron-impact ionization." International Journal of Mass Spectrometry. Accepted (2011). Abstract

Theoretical expressions for ionization cross sections by electron impact based on the binary encounter Bethe (BEB) model, valid from ionization threshold up to relativistic energies, are proposed.The new modified BEB (MBEB) and its relativistic counterpart (MRBEB) expressions are simpler than the BEB (nonrelativistic and relativistic) expressions because they require only one atomic parameter, namely the binding energy of the electrons to be ionized, and use only one scaling term for the ionization of all sub-shells.The new models are used to calculate the K-, L- and M-shell ionization cross sections by electron impact for several atoms with Z from 6 to 83.Comparisons with all, to the best of our knowledge, available experimental data show that this model is as good or better than other models, with less complexity.

Garcia-Alvarez, Begona, Roberto Melero, Fernando M. V. Dias, Jose A. M. Prates, Carlos M. G. A. Fontes, Steven P. Smith, Maria Joao Romao, Ana Luisa Carvalho, and Oscar Llorca. "Molecular Architecture and Structural Transitions of a Clostridium thermocellum Mini-Cellulosome." Journal of Molecular Biology. 407 (2011): 571-580. Abstract
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Nunes, G. N. N. V., Alberto Cardoso, A. Santos, and P. Gil. "Multi-agent Topologies over WSANs in the Context of Fault Tolerant Supervision." DoCEIS 2011 - 2nd Edition of the Doctoral Conference on Computing, Electrical and Industrial Systems. n/a 2011. Abstract
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Marques, Filipe J., and Carlos A. Coelho. "The Multi-sample Block-matrix Sphericity Test." AIP Conference Proceedings. Vol. 1389. AIP, 2011. 1479-1482. Abstract
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Figueiredo, Ondina M., Teresa Pereira Silva, and João Pedro Veiga. "Nanophases in the mineral world: the unique case of ferrihydrite." III Annual Meeting I3N. 2011. Abstract
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Fortunato, E., Barquinha Martins P. R. "New developments on oxide electronics." Proceedings of the International Display Workshops. Vol. 3. 2011. 1681-1684. Abstract

In this article we review the recent progress in n- and p-type oxide based thin film transistors (TFT), with special emphasis to solution-processed and p-type, and we will summarize the major milestones already achieved with this emerging and very promising technology.

Santos, J. P., M. Guerra, and F. Parente. "New expression for the K-shell ionization." Journal of Physics: Conference Series. Accepted (2011).
Mateus, O., J. Milàn, M. Romano, and M. A. Whyte. "New finds of stegosaur tracks from the Upper Jurassic Lourinhã formation, Portugal." Acta Palaeontologica Polonica. 56 (2011): 651-658. Abstract
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Filanovsky, I. M., M. Reja, and L. B. Oliveira. "New non-gyrator type active inductors with applications." Circuits and Systems (MWSCAS), 2011 IEEE 54th International Midwest Symposium on. IEEE, 2011. 1-4. Abstract
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Folgosa, F., C. M. Cordas, J. A. Santos, AS Pereira, JJG Moura, P. Tavares, and I. Moura. "New spectroscopic and electrochemical insights on a class I superoxide reductase: evidence for an intramolecular electron-transfer pathway." Biochemical Journal. 438 (2011): 485-494. AbstractWebsite

SORs (superoxide reductases) are enzymes involved in bacterial resistance to reactive oxygen species, catalysing the reduction of superoxide anions to hydrogen peroxide. So far three structural classes have been identified. Class I enzymes have two ironcentre-containing domains. Most studies have focused on the catalytic iron site (centre II), yet the role of centre I is poorly understood. The possible roles of this iron site were approached by an integrated study using both classical and fast kinetic measurements, as well as direct electrochemistry. A new heterometallic form of the protein with a zinc-substituted centre I, maintaining the iron active-site centre II, was obtained, resulting in a stable derivative useful for comparison with the native all-iron from. Second-order rate constants for the electron transfer between reduced rubredoxin and the different SOR forms were determined to be 2.8 x 10(7) M(-1) . s(-1) and 1.3 x 10(6) M(-1) . s(-1) for SOR(Fe(IIII)-Fe(II)) and for SOR(Fe(IIII)-Fe(III)) forms respectively, and 3.2 x 10(6) M(-1) s(-1) for the SOR(Zn(II)-Fe(III)) form. The results obtained seem to indicate that centre I transfers electrons from the putative physiological donor rubredoxin to the catalytic active iron site (intramolecular process). In addition, electrochemical results show that conformational changes are associated with the redox state of centre I, which may enable a faster catalytic response towards superoxide anion. The apparent rate constants calculated for the SOR-mediated electron transfer also support this observation.

Kiazadeh, A., H. L. Gomes, A. M. R. Da Costa, J. A. Moreira, D. M. De Leeuw, and S. C. J. Meskers. "Non-volatile memory device using a polymer modified nanocrystal." Materials Science and Engineering B: Solid-State Materials for Advanced Technology. 176 (2011): 1552-1555. Abstract
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Pina, João, Mário Ventim Neves, Alfredo Álvarez, and Amadeu Leão Rodrigues. "Numerical Design Methodology for an All Superconducting Linear Synchronous Motor." Technological Innovation for Sustainability. Vol. 349. IFIP Advances in Information and Communication Technology, 349. 2011. 553-562. Abstract

One potential advantage of the application of superconducting materials in electrical machines is the possibility to build lighter and compact devices by removing iron. These machines find applications, e.g., in systems where cryogenics is already available, or in naturally cryogenic environments. The design of motors with high temperature superconductors (HTS) presents issues unconsidered in classical machines, besides considerations on cryogenics, such as HTS brittleness or mechanical restrictions. Moreover, HTS' electromagnetic properties also degrade due to flux density components, which arise if there is no iron to guide magnetic flux. Several aspects must thus be considered in the design stage, as applications may turn less attractive or even unfeasible. In this paper these issues are detailed, and a numerical methodology for the design of an all superconducting (without iron or conventional conductors) linear synchronous motor is presented.

Coelho, Carlos A., and Filipe J. Marques. "On the Exact, Asymptotic and Near-exact Distributions for the Likelihood Ratio Statistics to Test Equality of Several Exponential Distributions." AIP Conference Proceedings. Vol. 1389. AIP, 2011. 1471-1474. Abstract
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Chen, Q., B. F. Bory, A. Kiazadeh, P. R. F. Rocha, H. L. Gomes, F. Verbakel, D. M. De Leeuw, and S. C. J. Meskers. "Opto-electronic characterization of electron traps upon forming polymer oxide memory diodes." Applied Physics Letters. 99 (2011). Abstract
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Domingues, T., J. R. Fernandes, and L. B. Oliveira. "Oscillator noise budget for ADC systems." Mixed Design of Integrated Circuits and Systems (MIXDES), 2011 Proceedings of the 18th International Conference. IEEE, 2011. 358-361. Abstract
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