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2012
Araújo, R., R. Castanhinha, O. Mateus, and R. Martins Late Jurassic theropod embryos from Porto das Barcas, Lourinhã formation, Portugal. Journal of Vertebrate Paleontology, Program and Abstracts, 2012, ISSN 1937-2809 ., 2012. Abstractaraujo_et_al_mateus_2012_dinosaur_eggs_portugal_svp_2012_abstract_book_meeting_abstracts.pdf.pdf

A clutch of several crushed eggs and embryos from the Late Jurassic (near the Kimmeridgian-Tithonian
boundary), Lourinhã Formation, Portugal contains a complete maxilla, erupted and scattered teeth,
and presacral vertebrae. The maxilla bears four teeth separated by individualized interdental plates,
the dorsal process of the maxilla is confluent with the maxillary body, the ventral rim of the antorbital
fossa is parallel to the tooth row, and the anterior border of the maxilla forms a right angle with the
ventral margin. The teeth are conical and recurved distally with carinae on mesial and distal sides. The
vertebrae are amphiplatyan, with a ventral pair of neurovascular foramina and heavily pitted articular
facets. These fossils allow unambiguous association of basal theropod osteology (Megalosauroidea) with
a new eggshell morphotype. Synchrotron micro-computed tomographic scanning (SRμCT), scanning
electron microscopy, and thin-sections under polarized and normal light revealed that the outer
ornamentation of the eggshell is composed of anastomosing ridges and islets, the pores communicate
near the outer region of the eggshells, and in radial section they are irregular canals that ramify towards
the surface. Micro-proto induced x-ray emission (micro-PIXE) analysis of the eggshell (excluding pores)
revealed the presence of Mg, Fe, Mn (0.33%, 0.27% and 0.18%, respectively) and several trace elements,
with a corresponding loss of Ca (39.4% detected but 40.0% expected for calcite), which suggests minimal
eggshell diagenesis. The eggshells do not luminesce, which could imply that no diagenetic alteration
took effect. However, the quenching effect of Fe2+ has to be taken into consideration. Conversely,
luminescence is observed in the pores since they are filled with sediment, composed of phyllosilicates,
as revealed by SRμCT, micro-PIXE and x-ray diffraction analyses.

Guimarães, D., M. L. Carvalho, M. Becker, A. von Bohlen, V. Geraldes, I. Rocha, and J. P. Santos. "Lead concentration in feces and urine of exposed rats by x-ray fluorescence and electrothermal atomic absorption spectrometry." X-Ray Spectrom.. 41 (2012): 80. Abstract

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"Learning introductory physics with computational modelling and interactive environments." Proceedings of the GIREP-EPEC 2011 Conference - Physics Alive. Jyvaskyla: University of Jyvaskyla, 2012. 208-213.
Guimarães, D., M. L. Carvalho, M. Becker, A. von Bohlen, V. Geraldes, I. Rocha, and J. P. Santos. "Lead concentration in feces and urine of exposed rats by x-ray fluorescence and electrothermal atomic absorption spectrometry." X-Ray Spectrometry. 41 (2012): 80. AbstractWebsite

Measurements made in feces and urine of Wistar rats exposed to lead acetate (n = 20) in drinking water since the fetal period were compared with those obtained from a control group (n = 20) in order to assess the age influence on Pb excretion. The measurements were made in different collections of rats aging between 1 and 11 months. To determine the Pb content of the samples, total reflection X-ray fluorescence (TXRF) and electrothermal atomic absorption spectrometry (ETAAS) were used for the urine samples and energy dispersive X-ray fluorescence (EDXRF) was used for the feces.The results show high concentrations of Pb being eliminated from the organism by urine and feces in contaminated rats. Values vary from (600`140)mgl1 to (5 460`115)mgl1 in urine and from (4 500`300)mgg1 to (11 400`3 300)mgg1 in dry feces. The control rats show, in general, low lead concentrations or below detection limits. The fecal/urinary ratio was studied. It was shown to be about three to four orders of magnitude and positively correlated with time. It was verified in feces and urine that excretion decreases with the animal age and that this decrease is made by different levels of excretion. The excretions of Pb in urine and in feces are positively correlated.A good agreement was found between the results obtained with TXRF and ETAAS for urine samples. This work also stresses the suitability of these techniques in the study of Pb intoxication.

Figueiredo, Ondina M., João Pedro Veiga, Teresa Pereira Silva, and José António Paulo Mirão. "Lead in jarosite: an X-ray absorption spectroscopy approach." 37th International Symposium on Environmental Analytical Chemistry, ISEAC-37. 2012. Abstract
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Lúcio, Válter, and Carlos Chastre. "Ligações rígidas em estruturas pré-fabricadas." Estruturas Pré-moldadas no Mundo - Aplicações e Comportamento Estrutural. Fundação da Faculdade de Ciências e Tecnologia da Universidade NOVA de Lisboa, 2012. 137-166. Abstract
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Alagador, D., M. Triviño, J. O. Cerdeira, R. Brás, M. Cabeza, and M. B. Araújo. "Linking like with like: Optimising connectivity between environmentally-similar habitats." Landscape Ecology. 27 (2012): 291-301. Abstract
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Carvalho, H., M. Maleki, and V. Cruz-Machado. "Links between supply chain disturbances and resilience strategies." International Journal of Agile Systems and Management. 5 (2012): 203-234. AbstractWebsite

The purpose of this paper is to establish links between supply chain disturbances and corresponding strategies of resilience to counter them. To this end, an inductive research approach is used, examining a sample of 38 cases. Secondary data from the cases is used to identify disturbances which affected the corresponding supply chains and the resilience strategies used by managers. The empirical evidences shows that the negative effects of supply chain disturbances can be categorised into a number of supply chain failure modes. In addition, a set of resilience strategies was identified that could be used to overcome those failure modes. A conceptual model, with links between supply chain disturbances, failures and resilience strategies, is proposed. The limitations of this research result from the use of secondary data sources. The findings are only valid for the selected case studies and, consequently, may not be applicable in other scenarios. Future research should focus on detailed case studies that investigate cross-functional applications across the organisation and the supply chain.

Geng, Yong, Pedro L. Almeida, João L. Figueirinhas, Eugene M. Terentjev, and Maria H. Godinho. "Liquid crystal beads constrained on thin cellulosic fibers: electric field induced microrotors and N–I transition." Soft Matter. 8.13 (2012): 3634-3640. Abstract
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Palma, L., F. Coito, and P. Gil. "Low Order Models for Human Controller - Mouse Interface." IEEE 16th International Conference on Intelligent Engineering Systems 2012, Lisbon, Portugal, June 13-15. n/a 2012. Abstract
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Abdollahvand, S., J. Goes, L. B. Oliveira, L. Gomes, and N. Paulino. "Low phase-noise temperature compensated self-biased ring oscillator." Circuits and Systems (ISCAS), 2012 IEEE International Symposium on. IEEE, 2012. 2489-2492. Abstract
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Figueiredo, M., J. Goes, L. B. Oliveira, and A. Steiger-Garção. "Low voltage low power fully differential self-biased 1.5-bit quantizer with built-in thresholds." International Journal of Circuit Theory and Applications (2012). Abstract
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Rocha, P. R. F., H. L. Gomes, L. K. J. Vandamme, Q. Chen, A. Kiazadeh, D. M. De Leeuw, and S. C. J. Meskers. "Low-frequency diffusion noise in resistive-switching memories based on metal-oxide polymer structure." IEEE Transactions on Electron Devices. 59 (2012): 2483-2487. Abstract
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Casaleiro, J., L. B. Oliveira, and I. M. Filanovsky. "Low-power and low-area CMOS quadrature RC oscillator with capacitive coupling." Circuits and Systems (ISCAS), 2012 IEEE International Symposium on. IEEE, 2012. 1488-1491. Abstract
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Inácio, David, João Pina, João Martins, Mário Ventim Neves, and Alfredo Álvarez. "Lumped Parameters Equivalent Circuit of a Superconducting Hysteresis Motor." EUCAS Conference 2011. Vol. 36. 2012. 975-979. Abstract

The potential advantage of using superconducting materials in electrical devices is well described in the literature. The electromagnetic properties of these materials make them unique for several applications, such as, e.g. electrical machines and drives, fault current applications, or superconducting magnetic energy storage. In the development of electromechanical conversion devices, superconducting materials are used foreseeing mainly a decrease in the device dimensions or a performance improvement for the same active volume. To guarantee a good application of this kind of materials it is important to describe and model the phenomena that characterize their operation under different regimes. In this paper, a study based in FEM simulations of a motor with bulk superconductor in the rotor is carried out, with the purpose of understand, quantify and qualify which phenomena are present in the different regimes of the motor, leading to obtaining an equivalent electrical circuit with lumped parameters.

2011
Craciunescu, C. M., R. M. Miranda, R. J. C. Silva, E. Assuncao, and F. M. Braz Fernandes. "Laser beam interaction with Ni-Mn-Ga ferromagnetic shape memory alloys." Optics and Lasers in Engineering. 49.11 (2011): 1289-1293. Abstract
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Timoteo, C. G., AS Pereira, C. E. Martins, S. G. Naik, A. G. Duarte, J. J. Moura, P. Tavares, BH HUYNH, and I. Moura. "Low-spin heme b(3) in the catalytic center of nitric oxide reductase from Pseudomonas nautica." Biochemistry. 50 (2011): 4251-62. AbstractWebsite

Respiratory nitric oxide reductase (NOR) was purified from membrane extract of Pseudomonas (Ps.) nautica cells to homogeneity as judged by polyacrylamide gel electrophoresis. The purified protein is a heterodimer with subunits of molecular masses of 54 and 18 kDa. The gene encoding both subunits was cloned and sequenced. The amino acid sequence shows strong homology with enzymes of the cNOR class. Iron/heme determinations show that one heme c is present in the small subunit (NORC) and that approximately two heme b and one non-heme iron are associated with the large subunit (NORB), in agreement with the available data for enzymes of the cNOR class. Mossbauer characterization of the as-purified, ascorbate-reduced, and dithionite-reduced enzyme confirms the presence of three heme groups (the catalytic heme b(3) and the electron transfer heme b and heme c) and one redox-active non-heme Fe (Fe(B)). Consistent with results obtained for other cNORs, heme c and heme b in Ps. nautica cNOR were found to be low-spin while Fe(B) was found to be high-spin. Unexpectedly, as opposed to the presumed high-spin state for heme b(3), the Mossbauer data demonstrate unambiguously that heme b(3) is, in fact, low-spin in both ferric and ferrous states, suggesting that heme b(3) is six-coordinated regardless of its oxidation state. EPR spectroscopic measurements of the as-purified enzyme show resonances at the g approximately 6 and g approximately 2-3 regions very similar to those reported previously for other cNORs. The signals at g = 3.60, 2.99, 2.26, and 1.43 are attributed to the two charge-transfer low-spin ferric heme c and heme b. Previously, resonances at the g approximately 6 region were assigned to a small quantity of uncoupled high-spin Fe(III) heme b(3). This assignment is now questionable because heme b(3) is low-spin. On the basis of our spectroscopic data, we argue that the g = 6.34 signal is likely arising from a spin-spin coupled binuclear center comprising the low-spin Fe(III) heme b(3) and the high-spin Fe(B)(III). Activity assays performed under various reducing conditions indicate that heme b(3) has to be reduced for the enzyme to be active. But, from an energetic point of view, the formation of a ferrous heme-NO as an initial reaction intermediate for NO reduction is disfavored because heme [FeNO](7) is a stable product. We suspect that the presence of a sixth ligand in the Fe(II)-heme b(3) may weaken its affinity for NO and thus promotes, in the first catalytic step, binding of NO at the Fe(B)(II) site. The function of heme b(3) would then be to orient the Fe(B)-bound NO molecules for the formation of the N-N bond and to provide reducing equivalents for NO reduction.

Carvalho, Helena, Susana Duarte, and Cruz V. Machado. "Lean, agile, resilient and green: divergencies and synergies." International Journal of Lean Six Sigma. 2 (2011): 151-179. AbstractWebsite

Purpose – This paper aims to explore the divergences and commitments between the lean, agile, resilient and green paradigms while investigating the effect of paradigms' practices within supply chain attributes.
Design/methodology/approach – A conceptual model with lean, agile, resilient and green practices and supply chain management attributes is proposed. Causal diagrams were used to represent the relationships between paradigm practices and supply chain attributes. The four diagrams were aggregated to build the conceptual model.
Findings – The conceptual model allows for the identification of synergies and divergences resulting from the paradigms practices implementation. The synergies between paradigms are related to “information frequency” and “integration level” increasing as well as reduction of “production lead time” and “transportation lead time”. However, other supply chain attributes such as “capacity surplus”, “inventory level” and “replenishment frequency” are affected in opposite directions by some paradigms creating divergences.
Research limitations/implications – The model relationships were established using an anecdotal approach derived from the literature review, reflecting only a partial view of supply chain dynamics. More research related to other supply chain attributes and/or paradigm practices, and validation of the proposed relationships is suggested.
Practical implications – The proposed model can be the basis for further research in lean, agile, resilient and green paradigms, contributing to a more sustainable and competitive lean supply chain with the necessary agility toward a quick response, resiliency to disruptions, and harmonization with the ecologic and environmental aspects. Originality/value – To the authors' knowledge this paper is the first to provide an understanding about the tradeoffs among lean, agile, resilient and green supply chain paradigms.

Diogo, Aurelio, Grilo Antonio, and Cruz-Machado Virgilio. "Lean management appropriateness: key potential limiting factors." Industrial Engineering and Engineering Management Conferences. 2011. 779-783. Abstract
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Carvalho, Helena, Susana Duarte, and Cruz} {V. Machado. "Lean, agile, resilient and green: divergencies and synergies." International Journal Of Lean Six Sigma. 2 (2011): 151-179. Abstract

Purpose - This paper aims to explore the divergences and commitments between the lean, agile, resilient and green paradigms while investigating the effect of paradigms’ practices within supply chain attributes. Design/methodology/approach - A conceptual model with lean, agile, resilient and green practices and supply chain management attributes is proposed. Causal diagrams were used to represent the relationships between paradigm practices and supply chain attributes. The four diagrams were aggregated to build the conceptual model. Findings - The conceptual model allows for the identification of synergies and divergences resulting from the paradigms practices implementation. The synergies between paradigms are related to “information frequency” and “integration level” increasing as well as reduction of “production lead time” and “transportation lead time”. However, other supply chain attributes such as “capacity surplus”, “inventory level” and “replenishment frequency” are affected in opposite directions by some paradigms creating divergences. Research limitations/implications - The model relationships were established using an anecdotal approach derived from the literature review, reflecting only a partial view of supply chain dynamics. More research related to other supply chain attributes and/or paradigm practices, and validation of the proposed relationships is suggested. Practical implications - The proposed model can be the basis for further research in lean, agile, resilient and green paradigms, contributing to a more sustainable and competitive lean supply chain with the necessary agility toward a quick response, resiliency to disruptions, and harmonization with the ecologic and environmental aspects. Originality/value - To the authors’ knowledge this paper is the first to provide an understanding about the tradeoffs among lean, agile, resilient and green supply chain paradigms.

A, Velhinho, and Rocha LA. "Longitudinal centrifugal casting of metal-matrix functionally graded composites: an assessment of modelling issues." JOURNAL OF MATERIALS SCIENCE. 46 (2011): 3753-3765. Abstract
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Craciunescu, C. M., R. M. Miranda, R. J. C. Silva, E. Assunção, and F. M. Braz Fernandes. "Laser beam interaction with NiMnGa ferromagnetic shape memory alloys." Optics and Lasers in Engineering. 49.11 (2011): 1289-1293. AbstractWebsite
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Knorr, Matthias, José Júlio Alferes, and Pascal Hitzler. "Local closed world reasoning with description logics under the well-founded semantics." Artificial Intelligence. 175 (2011): 1528-1554. Abstractai11.pdf

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Duarte, Filipe J. S., Snezhana M. Bakalova, Eurico J. Cabrita, and Gil A. Santos. "Lewis Acid Catalyzed Reactions of Chiral Imidazolidinones and Oxazolidinones: Insights on the Role of the Catalyst." Journal of Organic Chemistry. 76.17 (2011): 6997-7004. Abstract

The mechanism proposed by Evans to justify the selectivity obtained in Lewis acid catalyzed Diels-Alder reactions of cyclopentadiene with acyloxazolidinones has been generalized and used in the rationalization of selectivities obtained in many other systems. However, we recently proposed an alternative mechanism, on the basis of open-chain mono- and bicomplexes, that avoids the need for chelates and explains the selectivity obtained by Evans. In this manuscript we apply our proposal to the catalyzed conjugated addition of amines to acylimidazolidinones, reported by Cardillo, and we clearly show that aluminum chelates are not involved in the reaction, as they induce no selectivity, while Cardillo observed high experimental selectivities. Our data equally show that bicomplexes with carbonyl parallel orientation, proposed by Cardillo to justify the experimental selectivity with nonchelating Lewis acids, indeed induce the opposite selectivity and have also to be dismissed. On the other hand, our mechanistic proposal allows for the full rationalization of the data obtained by Cardillo with aluminum, boron, or zinc Lewis acids and supports our previous proposal on DA cycloadditions of dienes to Evans chiral auxiliary derivatives.

Barros, M. T., K. T. Petrova, P. Correia-da-Silva, and T. M. Potewar. "Library of Mild and Economic Protocols for the Selective Derivatization of Sucrose under Microwave Irradiation." Green Chem. 13.7 (2011): 1897-1906. DOI: 10.1039/c1gc15228a.