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2011
Mateus, Octávio, Louis L. Jacobs, Anne S. Schulp, Michael J. Polcyn, Tatiana S. Tavares, André Buta Neto, Maria Lu{\'ı}sa Morais, and Miguel T. Antunes. "Angolatitan adamastor, a new sauropod dinosaur and the first record from Angola." Anais da Academia Brasileira de Ciências. 83 (2011): 221-233. AbstractWebsite
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Mateus, Octávio, Octávio Mateus, Louis L. Jacobs, Anne S. Schulp, Michael J. Polcyn, Tatiana S. Tavares, André Buta Neto, Maria Luísa Morais, and Miguel T. Antunes. "Angolatitan adamastor, a new sauropod dinosaur and the first record from Angola." Anais da Academia Brasileira de Ciências (2011). Abstract
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Araújo, João, Vítor H. Fernandes, Manuel M. Jesus, Victor Maltcev, and James D. Mitchell. "Automorphisms of partial endomorphism semigroups." Publ. Math. Debrecen. 79 (2011): 23-39. AbstractWebsite
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Martins, R., B. Brás, I. Ferreira, L. Pereira, P. Barquinha, N. Correia, R. Costa, T. Busani, A. Gonçalves, and A. Pimentel Away from silicon era: the paper electronics. SPIE OPTO. International Society for Optics and Photonics, 2011. Abstract
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Martins, R., B. Bras, I. Ferreira, L. Pereira, P. Barquinha, N. Correia, R. Costa, T. Busani, A. Goncalves, A. Pimentel, and E. Fortunato. "Away from silicon era: the paper electronics." Oxide-Based Materials and Devices Ii. Eds. F. H. Teherani, D. C. Look, and D. J. Rogers. Vol. 7940. Proceedings of SPIE, 7940. 2011. Abstract
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Martins, R., Brás Ferreira Pereira Barquinha Correia Costa Busani Gonçalves Pimentel Fortunato B. I. L. "Away from silicon era: The paper electronics." Proceedings of SPIE - The International Society for Optical Engineering. Vol. 7940. 2011. Abstract

Today there is a strong interest in the scientific and industrial community concerning the use of biopolymers for electronic applications, mainly driven by low-cost and disposable applications. Adding to this interest, we must recognize the importance of the wireless auto sustained and low energy consumption electronics dream. This dream can be fulfilled by cellulose paper, the lightest and the cheapest known substrate material, as well as the Earth's major biopolymer and of tremendous global economic importance. The recent developments of oxide thin film transistors and in particular the production of paper transistors at room temperature had contributed, as a first step, for the development of disposable, low cost and flexible electronic devices. To fulfil the wireless demand, it is necessary to prove the concept of self powered devices. In the case of paper electronics, this implies demonstrating the idea of self regenerated thin film paper batteries and its integration with other electronic components. Here we demonstrate this possibility by actuating the gate of paper transistors by paper batteries. We found that when a sheet of cellulose paper is covered in both faces with thin layers of opposite electrochemical potential materials, a voltage appears between both electrodes - paper battery, which is also self-regenerated. The value of the potential depends upon the materials used for anode and cathode. An open circuit voltage of 0.5V and a short-circuit current density of 1μA/cm2 were obtained in the simplest structure produced (Cu/paper/Al). For actuating the gate of the paper transistor, seven paper batteries were integrated in the same substrate in series, supplying a voltage of 3.4V. This allows proper ON/OFF control of the paper transistor. Apart from that transparent conductive oxides can be also used as cathode/anode materials allowing so the production of thin film batteries with transparent electrodes compatible with flexible, invisible, self powered and wireless electronics. © 2011 SPIE.

Feizi, Ten, Yan Liu, and Angelina S. Palma. "Bacterial, Fungal, and Algal Lectins: Combatants in Tug of War against HIV." Structure. 19 (2011): 1035-1037. Abstract
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Fernandes, Vítor H., and Teresa M. Quinteiro. "Bilateral semidirect product decompositions of transformation monoids." Semigroup Forum. 82 (2011): 271-287. Abstract
Summary: In this paper we consider the monoid $\mathcal {OR}_{n}$ of all full transformations on a chain with $n$ elements that preserve or reverse the orientation, as well as its submonoids $\mathcal {OD}_{n}$ of all order-preserving or order-reversing elements, $\mathcal {OP}_{n}$ of all orientation-preserving elements and $\mathcal {O}_{n}$ of all order-preserving elements. By making use of some well known presentations, we show that each of these four monoids is a quotient of a bilateral semidirect product of two of its remarkable submonoids.
Amaro, P., A. Surzhykov, F. Parente, P. Indelicato, and J. P. Santos. "Calculation of two-photon decay rates of hydrogen-like ions by using B-polynomials." Journal of Physics A: Mathematical and Theoretical. 44 (2011): 245302. AbstractWebsite
A new approach is laid out to investigate two-photon atomic transitions. It is based on the application of the finite-basis solutions constructed from the Bernstein polynomial (B-polynomial) sets. We show that such an approach provides a very promising route for the relativistic second-order (and even higher-order) calculations since it allows for analytical evaluation of the involved matrices elements. In order to illustrate possible applications of the method and to verify its accuracy, detailed calculations are performed for the 2 s 1/2 ‚Üí 1 s 1/2 transition in neutral hydrogen and hydrogen-like ions, which are compared with the theoretical predictions based on the well-established B-spline basis-set approach.
Amaro, P., A. Surzhykov, F. Parente, P. Indelicato, and J. P. Santos. "Calculation of two-photon decay rates of hydrogen-like ions by using B-polynomials." Journal of Physics A: Mathematical and Theoretical. 44 (2011): 245302. AbstractWebsite

A new approach is laid out to investigate two-photon atomic transitions. It is based on the application of the finite-basis solutions constructed from the Bernstein polynomial (B-polynomial) sets. We show that such an approach provides a very promising route for the relativistic second-order (and even higher-order) calculations since it allows for analytical evaluation of the involved matrices elements. In order to illustrate possible applications of the method and to verify its accuracy, detailed calculations are performed for the 2 s 1/2 ‚Üí 1 s 1/2 transition in neutral hydrogen and hydrogen-like ions, which are compared with the theoretical predictions based on the well-established B-spline basis-set approach.

Pinto, LFV, S. Kundu, P. Brogueira, C. Cruz, S. N. Fernandes, A. Aluculesei, and M. H. Godinho. "Cellulose-based liquid crystalline photoresponsive films with tunable surface wettability." Langmuir. 27.10 (2011): 6330-6337. Abstract
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Nolan, M.G.a, Hamilton Obrien Bruno Pereira Fortunato Martins Povey Pemble J. A. a S. "The characterisation of aerosol assisted CVD conducting, photocatalytic indium doped zinc oxide films." Journal of Photochemistry and Photobiology A: Chemistry. 219 (2011): 10-15. AbstractWebsite

Indium doped, and undoped, zinc oxide films were deposited using aerosol assisted chemical vapour deposition (AACVD) at atmospheric pressure on glass substrates. Electrical measurements (I-V) showed a reduction in resistivity following the addition of indium, and XRD analysis revealed an associated switch to c-axis preferred crystal orientation. The ability of the films to oxidise organic material on their surface was analysed using stearic acid as the model contaminant under ultra-violet (UV, 365 nm) irradiation. The In-doped films displayed a greater rate of organic decomposition, which we attribute to the formation of a platelet surface structure having a larger surface area than the undoped films, on which the UV generated electrons and holes may react to form active photocatalytic species. In addition we suggest that the switch to c-axis crystal orientation may reduce the electron-hole pair recombination rate at the grain boundaries, due to an improvement in crystallinity and related reduction in carrier scattering losses, leading to an increase in photocatalytic organic decomposition rate. © 2011 Elsevier B.V. All rights reserved.

Santin, E., M. Figueiredo, J. Goes, and L. Oliveira. "CMOS Fully Differential Feedforward-Regulated Folded Cascode Amplifier." Technological Innovation for Sustainability (2011): 565-572. Abstract
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Martins, Rodrigo, Arokia Nathan, Raquel Barros, LuÍs Pereira, Pedro Barquinha, Nuno Correia, Ricardo Costa, Arman Ahnood, Isabel Ferreira, and Elvira Fortunato. "Complementary metal oxide semiconductor technology with and on paper." Advanced Materials. 23.39 (2011): 4491-4496. Abstract
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Martins, R.a, Nathan Barros Pereira Barquinha Correia Costa Ahnood Ferreira Fortunato A. b R. a. "Complementary metal oxide semiconductor technology with and on paper." Advanced Materials. 23 (2011): 4491-4496. AbstractWebsite

A complementary metal oxide semiconductor (CMOS) device is described. The device is based on n-(In-Ga-Zn-O) and p-type (SnO x) active oxide semiconductors and uses a transparent conductive oxide (In-Zn-O) as gate electrode that sits on a flexible, recyclable paper substrate that is simultaneously the substrate and the dielectric. Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Santos-Silva, T., A. Mukhopadhyay, J. D. Seixas, G. J. L. Bernardes, C. C. Romão, and MJ Romão. "CORM-3 reactivity toward proteins: The crystal structure of a Ru(II) dicarbonyl-lysozyme complex." Journal of the American Chemical Society. 133 (2011): 1192-1195. Abstract
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Dias, MI, Ondina M. Figueiredo, Antónia M. Matos, A. Pais, Maria Isabel Prudêncio, Teresa Pereira Silva, Christopher Ian Burbidge, A. L. Rodrigues, and João Pedro Veiga. "Datação, autenticidade, materiais e pigmentos. Estudos laboratoriais sobre faiança portuguesa e porcelana chinesa produzida para o mercado português, séculos XVI a XVIII." IX Congresso Ibérico de Arqueometria (CIA). 2011. Abstract
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Carvalho, Carlos, Guilherme Lavareda, and Nuno Paulino. "A DC-DC Step-Up mu-Power Converter for Energy Harvesting Applications, Using Maximum Power Point Tracking, Based on Fractional Open Circuit Voltage." TECHNOLOGICAL INNOVATION FOR SUSTAINABILITY. Ed. LM CamarinhaMatos. Vol. 349. IFIP Advances in Information and Communication Technology, 349. Soc Collaborat Networks; IFIP WG 5.5 COVE CoOperation Infrastructure Virtual Enterprises & Elect Business; IEEE Ind Elect Soc; U2; Uninova, 2011. 510-517. Abstract

A DC-DC step-up micro power converter for solar energy harvesting applications is presented. The circuit is based on a switched-capacitor voltage tripler architecture with MOSFET capacitors, which results in an, area approximately eight times smaller than using MiM capacitors for the 0.131 mu m CMOS technology. In order to compensate for the loss of efficiency, due to the larger parasitic capacitances, a charge reutilization scheme is employed. The circuit is self-clocked, using a phase controller designed specifically to work with an amorphous silicon solar cell, in order to obtain the maximum available power from the cell. This will be done by tracking its maximum power point (MPPT) using the fractional open circuit voltage method. Electrical simulations of the circuit, together with an equivalent electrical model of an amorphous silicon solar cell, show that the circuit can deliver a power of 1132 mu W to the load, corresponding to a maximum efficiency of 66.81%.

Filanovsky, I. M., and L. B. Oliveira. "Design of a MOS RLC-oscillator with specified total harmonic distortion." Circuits and Systems (MWSCAS), 2011 IEEE 54th International Midwest Symposium on. IEEE, 2011. 1-4. Abstract
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Palma, L., F. Coito, P. Gil, and R. N. d Silva. "Design of Adaptive PCA Controllers for SISO Systems." 18th IFAC World Congress. n/a 2011. Abstract
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Louren{\c c}o, João, Diogo Sousa, Bruno C. Teixeira, and Ricardo Dias. "Detecting concurrency anomalies in transactional memory programs." Comput. Sci. Inf. Syst.. 8 (2011). Abstract
Software transactional memory is a promising programming model that adapts many concepts borrowed from the databases world to control concurrent accesses to main memory (RAM). This paper discusses how to support revertible operations, such as memory allocation and release, within software libraries that will be used in software memory transactional contexts. The proposal is based in the extension of the transaction life cycle state diagram with new states associated to the execution of user-defined handlers. The proposed approach is evaluated in terms of functionality and performance by way of a use case study and performance tests. Results demonstrate that the proposal and its current implementation are flexible, generic and efficient
Spagnolo, A., G. Marchi, F. Peduto, AJL Phillips, and G. Surico. "Detection of Botryosphaeriaceae species within grapevine woody tissues by nested PCR, with particular emphasis on the Neofusicoccum parvum/N. ribis complex." European Journal of Plant Pathology. 129 (2011): 485-500. Abstract
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Martins, R. M. S., F. Beckmann, R. Castanhinha, O. Mateus, and P. K. Pranzas. "Dinosaur and crocodile fossils from the mesozoic of Portugal: Neutron tomography and synchrotron-radiation based micro-computed tomography." Materials Research Society Symposium Proceedings. 1319 (2011): 319-332. Abstract
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Neagu, E. R., C. J. Dias, M. C. Lanca, R. Igreja, P. Inacio, J. N. Marat-Mendes, and Ieee Discrimination between Space Charge and Dipolar Contributions in Ferroelectric Polymers., 2011. Abstract

The final thermally stimulated discharge current method allows a better selection of the experimental conditions for sample polarization. By decreasing the ratio between the charging time and the discharging time, the apparent peak is of the same order of magnitude as the genuine peaks and there is only a partial overlap between then. Two peaks have been identified for polyamide 11, one associated with the glass transition around 60 degrees C and the second associated with the Curie transition around 96 degrees C.

R., Neagu E., C. Dias, Lança M. Carmo, Igreja R., Inacio P., and Marat-Mendes J. N. "Discrimination between Space Charge and Dipolar Contributions in Ferroelectric Polymers." 14th International Symposium on Electrets. International Symposium on Electrets. 2011. Abstract

The final thermally stimulated discharge current method allows a better selection of the experimental conditions for sample polarization. By decreasing the ratio between the charging time and the discharging time, the apparent peak is of the same order of magnitude as the genuine peaks and there is only a partial overlap between then. Two peaks have been identified for polyamide 11, one associated with the glass transition around 60 °C and the second associated with the Curie transition around 96 °C.