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2011
Araújo, J., J. D. Mitchell, and Csaba Schneider. "Groups that together with any transformation generate regular semigroups for idempotent generated semigroups." J. Algebra. 343 (2011): 93-106. AbstractWebsite
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Pereira, Ricardo, J. Coutinho, A. Carvalho, L. Pereira, L. Rino, VJB Torres, Lu{\'ıs de Almeida, Sergej Filonovich, T. Busani, H. Águas, and others. "Hybridsolar project: hybrid Si-Nanoparticle/polymer layers for solar cell applications." III Annual Meeting of the I3N–Institute of Nanostructures, Nanomodelling and Nanofabrication, 2011. 2011. 10. Abstract
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Araújo, João, and Michael Kinyon. "Independent axiom systems for nearlattices." Czechoslovak Math. J.. 61(136) (2011): 975-992. AbstractWebsite
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Azevedo, S. G., H. Carvalho, and V. Cruz-Machado. "The influence of green practices on supply chain performance: A case study approach." Transportation Research Part E: Logistics and Transportation Review. 47 (2011): 850-871. AbstractWebsite

The main objective of this exploratory paper is to investigate the relationships between green practices of supply chain management and supply chain performance. This relationship is investigated in the context of the automotive industry. Five research propositions are suggested and tested with empirical data derived from five case studies taken from the Portuguese automotive supply chain. The data analysis identifies the most important green practices considered by managers, as well as the performance measures that are most appropriate and most widely used as means to evaluate the influence of green practices on supply chain performance. A conceptual model was derived from the data analysis and it can be used to assess the influence of green practices on supply chain performance. This model provides evidence as to which green practices have positive effects on quality, customer satisfaction and efficiency. It also identifies the practices which have negative effects on supply chain performance.

A., Pedrosa, LANÇA M.C., Borges J.P., NEAGU E.R., DIAS C.J., Marat-Mendes, and J.N. "Influence of Polarization on the Bioactivity of Nanopowders of Hydroxyapatite." 14th International Symposium on Electrets. International Symposium on Electrets. 2011. Abstract
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Pinheiro, Carla, Carla Antonio, Maria Fernanda Ortuno, Petre I. Dobrev, Wolfram Hartung, Jane Thomas-Oates, Candido Pinto Ricardo, Radomira Vankova, Manuela M. Chaves, and Julie C. Wilson. "Initial water deficit effects on Lupinus albus photosynthetic performance, carbon metabolism, and hormonal balance: metabolic reorganization prior to early stress responses." Journal of Experimental Botany. 62 (2011): 4965-4974. AbstractWebsite

The early (2-4 d) effects of slowly imposed soil water deficit on Lupinus albus photosynthetic performance, carbon metabolism, and hormonal balance in different organs (leaf blade, stem stele, stem cortex, and root) were evaluated on 23-d-old plants (growth chamber assay). Our work shows that several metabolic adjustments occurred prior to alteration of the plant water status, implying that water deficit is perceived before the change in plant water status. The slow, progressive decline in soil water content started to be visible 3 d after withholding water (3 DAW). The earliest plant changes were associated with organ-specific metabolic responses (particularly in the leaves) and with leaf conductance and only later with plant water status and photosynthetic rate (4 DAW) or photosynthetic capacity (according to the Farquhar model; 6 DAW). Principal component analysis (PCA) of the physiological parameters, the carbohydrate and the hormone levels and their relative values, as well as leaf water-soluble metabolites full scan data (LC-MS/MS), showed separation of the different sampling dates. At 6 DAW classically described stress responses are observed, with plant water status, ABA level, and root hormonal balance contributing to the separation of these samples. Discrimination of earlier stress stages (3 and 4 DAW) is only achieved when the relative levels of indole-3-acetic acid (IAA), cytokinins (Cks), and carbon metabolism (glucose, sucrose, raffinose, and starch levels) are taken into account. Our working hypothesis is that, in addition to single responses (e.g. ABA increase), the combined alterations in hormone and carbohydrate levels play an important role in the stress response mechanism. Response to more advanced stress appears to be associated with a combination of cumulative changes, occurring in several plant organs. The carbohydrate and hormonal balance in the leaf (IAA to bioactive-Cks; soluble sugars to IAA and starch to IAA; relative abundances of the different soluble sugars) flag the initial responses to the slight decrease in soil water availability (10-15% decrease). Further alterations in sucrose to ABA and in raffinose to ABA relative values (in all organs) indicate that soil water availability continues to decrease. Such alterations when associated with changes in the root hormone balance indicate that the stress response is initiated. It is concluded that metabolic balance (e.g. IAA/bioactive Cks, carbohydrates/IAA, sucrose/ABA, raffinose/ABA, ABA/IAA) is relevant in triggering adjustment mechanisms.

Pinheiro, Carla, Carla Antonio, Maria Fernanda Ortuno, Petre I. Dobrev, Wolfram Hartung, Jane Thomas-Oates, Candido Pinto Ricardo, Radomira Vankova, Manuela M. Chaves, and Julie C. Wilson. "Initial water deficit effects on Lupinus albus photosynthetic performance, carbon metabolism, and hormonal balance: metabolic reorganization prior to early stress responses." Journal of Experimental Botany. 62 (2011): 4965-4974. AbstractWebsite
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Antunes, R., F. Coito, and H. Duarte-Ramos. "A Linear Approach towards Modeling Human Behavior." Technological Innovation for Sustainability (2011): 305-314. 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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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.

Aelenei, Laura, Roberto Lollini, Helder Gon, Daniel Aelenei, Masa Noguchi, Michael Donn, and Fran Garde. "Passive cooling approaches in net-zero energy solar buildings: lessons learned from demonstration buildings." CISBAT 2011 - CleanTec for Sustainable Buildings. 978-2-8399-0906-8. 2011. Abstract
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Antão, Armando N., T. Santana, M. Vicente da Silva, and N. M. C. Guerra. "Passive earth-pressure coefficients by upper-bound numerical limit analysis." Canadian Geotechnical Journal. 48 (2011): 767-780. Abstract

A three-dimensional (3D) numerical implementation of the limit analysis upper-bound theorem is used to determine passive horizontal earth-pressure coefficients. An extension technique allowing determination of the 3D passive earth pressures for any width-to-height ratios greater than 7 is presented. The horizontal passive earth-pressure coefficients are presented and compared with solutions published previously. Results of the ratio between the 3D and two-dimensional horizontal passive earth-pressure coefficients are shown and found to be almost independent of the soil-to-wall friction ratio. A simple equation is proposed for calculating this passive earth-pressure ratio.

Alagador, D., M. J. Martins, J. O. Cerdeira, M. Cabeza, and M. B. Araújo. "A probability-based approach to match species with reserves when data are at different resolutions." Biological Conservation. 144 (2011): 811-820. Abstract
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Silva, A., D. Cavalheiro, S. Abdollahvand, L. B. Oliveira, M. Figueiredo, and J. Goes. "A self-biased ring oscillator with quadrature outputs operating at 600 MHz in a 130 nm CMOS technology." Mixed Design of Integrated Circuits and Systems (MIXDES), 2011 Proceedings of the 18th International Conference. IEEE, 2011. 221-224. Abstract
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Queirós, Alexandra, Pedro Conde, Vera Cunha, Paula Ambrósio, Filipe J. Marques, and Fátima Serrano. "Sexuality in the third trimester of pregnancy." Revista Portuguesa de Cl{\'ınica Geral. 27 (2011): 434-443. Abstract
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Águas, Hugo, Sanjay K. Ram, Andreia Araújo, Diana Gaspar, António Vicente, Sergej A. Filonovich, Elvira Fortunato, Rodrigo Martins, and Isabel Ferreira. "Silicon thin film solar cells on commercial tiles." Energy & Environmental Science. 4.11 (2011): 4620-4632. Abstract
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Águas, H., Ram Araújo Gaspar Vicente Filonovich Fortunato Martins Ferreira S. K. A. "Silicon thin film solar cells on commercial tiles." Energy and Environmental Science. 4 (2011): 4620-4632. AbstractWebsite

Nanostructured silicon single junction thin film solar cells were deposited on commercial red clay roof tiles with engobe surfaces and earthenware wall tiles with glazed surfaces, with a test area of 24 mm 2. We studied the influence of the type of substrate tile, back contact, buffer layer and SiO x passivation layer on the optoelectronic performance of the solar cells. Despite the fact that typical micrometre-sized defects on the surfaces of the tiles and the porous nature of the ceramic substrates make deposition of homogeneous thin films on them quite challenging, we have been able to achieve a cell efficiency of 5% and a quantum efficiency of 80% on non-fully optimized cells on commercial tiles. The method is industrially employable utilizing pre-existing plasma-enhanced chemical vapour deposition technologies. The cost-effectiveness and industrial feasibility of the technique are discussed. Our study shows that photovoltaic tiles can combine energy generation with architectural aesthetics leading to significant implications for advancement in building integrated photovoltaics. © 2011 The Royal Society of Chemistry.

Águas, Hugo, Sanjay K. Ram, Andreia Araújo, Diana Gaspar, António Vicente, Sergej A. Filonovich, Elvira Fortunato, Rodrigo Martins, and Isabel Ferreira. "Silicon thin film solar cells on commercial tiles." Energy & Environmental Science. 4 (2011): 4620-4632. Abstract
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Barbosa, Paulo E. S., João Paulo Barros, Franklin Ramalho, Lu{\'ı}s Gomes, Jorge Figueiredo, Filipe Moutinho, Anikó Costa, and André Aranha. "SysVeritas: {A} Framework for Verifying {IOPT} Nets and Execution Semantics within Embedded Systems Design." Technological Innovation for Sustainability - Second {IFIP} {WG} 5.5/SOCOLNET Doctoral Conference on Computing, Electrical and Industrial Systems, DoCEIS 2011, Costa de Caparica, Portugal, February 21-23, 2011. Proceedings. 2011. 256-265. Abstract
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Tillak, JB, I. Bernacka-Wojcik, D. Barata, PAS Jorge, H. Águas, and AG Oliva. "Towards single cell spectroscopy and refractometry in microfluidic chip platforms." International Conference on Applications of Optics and Photonics. International Society for Optics and Photonics, 2011. 800112. Abstract
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