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2009
Godinho, M. H., João P. Canejo, LFV Pinto, J. P. Borges, and Paulo Ivo Cortez Teixeira. "How to mimic the shapes of plant tendrils on the nano and microscale: spirals and helices of electrospun liquid crystalline cellulose derivatives." Soft Matter. 5.14 (2009): 2772-2776. Abstract
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Elangovan, E., Martins Fortunato R. E. "Indium molybdenum oxide thin films: A comparative study by two different RF sputtering systems." Physica Status Solidi (A) Applications and Materials Science. 206 (2009): 2123-2127. AbstractWebsite

Indium molybdenum oxide thin films were deposited using different radio-frequency sputtering units on glass substrates at room temperature from an In 2O 3 (95 wt.%): Mo (5 wt.%) target. The film thickness ranges between 160 and 275 nm. The chamber volume of Unit-1 was ̃2.4 times larger than that of Unit-2. Apart from the chamber volume, a significant difference between the two units was the sputtering pressure. The films were characterized by their structural, morphological, optical, and electrical properties. A strong reflection from (222) plane was obtained for the ̃275 nm thick films deposited in Unit-1. The films deposited with <275 nm thickness and those deposited in Unit-2 are close to amorphous with a small crystalline fraction. The surface of the films deposited in Unit-1 is comprised of randomly arranged crystallites, which is restructured with the increasing film thickness to become a well defined "rice field" like structure (275 nm thick). The films deposited in Unit-2 are comprised of many holes on the surface that is presumably due to back sputtering. The average visible transmittance calculated in the wavelength between 400 and 800 nm ranges from 70 to 82%. The optical band gap is found to vary between 3.80 and 3.86 eV. The lowest bulk resistivity of the films deposited in Unit-1 was increased from ̃4.06×10 -3 to 4.07×10 -1ωcm when deposited in Unit-2. The carrier concentration was decreased from 1.31×10 20 to 1.03×10 18 cm -3 but the Hall mobility increased from 11.7 to 15.0 cm2 V -1 s -1. © 2009 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

"International Conference on the Geological Collections and Museums: mission and management." Eds. J. Brandao, P. Callapez, O. Mateus, and P. Castro. 2009. Abstract
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Wang, J.a, Martins Barradas Alves Monteiro Peres Elamurugu Fortunato R. a N. P. "Intrinsic P type ZNO films deposited by RF magnetron sputtering." Journal of Nanoscience and Nanotechnology. 9 (2009): 813-816. AbstractWebsite

ZnO films were deposited on c-plane sapphire substrates in Ar atmosphere by ii magnetron sputtering and were post-annealed at 400°C in green gas (95% N2 + 5% H2). The properties of the as-grown and annealed films have been characterized by X-ray diffraction (XRD), Rutherford backscattering (RBS), elastic recoil detection analysis (ERDA), Hall measurement and photoluminescence spectra. XRD studies confirmed the variation in strain and an improvement in crystallinity. From RBS and ERDA analysis, the presence of H atoms on the surface of the as-grown ZnO films was evidenced. Annealing in green gas increased the amount of H in the film. Compared with the as-grown films, the ultra exciting intensity obviously decreases in the annealed films and new optical active centres in the blue/violet ( 3.0 eV) and red ( 1.9) regions are emerged in the PL spectrum. The positive sign of Hall coefficient confirmed the low (-type conductivity in the as grown films, which was improved after annealing. However, the (-type conductivity was not stable, especially for the annealed sample it changes from ( type to n type after 9 days. Copyright © 2009 American Scientific Publishers All rights reserved.

Rivas, M. G., C. S. Mota, S. R. Pauleta, M. S. P. Carepo, F. Folgosa, S. L. A. Andrade, G. Fauque, AS Pereira, P. Tavares, JJ Calvete, I. Moura, and JJG Moura. "Isolation and characterization of a new Cu-Fe protein from Desulfovibrio aminophilus DSM12254." Journal of Inorganic Biochemistry. 103 (2009): 1314-1322. AbstractWebsite

The isolation and characterization of a new metalloprotein containing Cu and Fe atoms is reported. The as-isolated Cu-Fe protein shows an UV-visible spectrum with absorption bands at 320 nm, 409 nm and 615 nm. Molecular mass of the native protein along with denaturating electrophoresis and mass spectrometry data show that this protein is a multimer consisting of 14 +/- 1 subunits of 15254.3 +/- 7.6 Da. Mossbauer spectroscopy data of the as-isolated Cu-Fe protein is consistent with the presence of [2Fe-2S](2+) centers. Data interpretation of the dithionite reduced protein suggest that the metallic cluster could be constituted by two ferromagnetically coupled [2Fe-2S](+) spin delocalized pairs. The biochemical properties of the Cu-Fe protein are similar to the recently reported molybdenum resistance associated protein from Desulfovibrio, D. alaskensis. Further-more, a BLAST search from the DNA deduced amino acid sequence shows that the Cu-Fe protein has homology with proteins annotated as zinc resistance associated proteins from Desulfovibrio, D. alaskensis, D. vulgaris Hildenborough, D. piger ATCC 29098. These facts suggest a possible role of the Cu-Fe protein in metal tolerance. (C) 2009 Published by Elsevier Inc.

Santos-Silva, T., F. Ferroni, A. Thapper, J. Marangon, P. J. González, A. C. Rizzi, I. Moura, JJG Moura, MJ Romão, and CD Brondino. "Kinetic, structural, and EPR studies reveal that aldehyde oxidoreductase from Desulfovibrio gigas does not need a sulfido ligand for catalysis and give evidence for a direct Mo-C interaction in a biological system." Journal of the American Chemical Society. 131 (2009): 7990-7998. Abstract
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Liu, Yan, Angelina S. Palma, Wengang Chai, Claudia Muhle-Goll, Yukishige Ito, and Ten Feizi. "The Latest on Malectin - A Lectin of the Endoplasmic Reticulum." Glycobiology. 19 (2009): 1301-1302. Abstract
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Godinho, M. H., D. Filip, I. Costa, A. - L. Carvalho, J. L. Figueirinhas, and E. M. Terentjev. "Liquid crystalline cellulose derivative elastomer films under uniaxial strain." Cellulose. 16 (2009): 199-205. Abstract
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Godinho, M. H., D. Filip, I. Costa, A. - L. Carvalho, J. L. Figueirinhas, and E. M. Terentjev. "Liquid crystalline cellulose derivative elastomer films under uniaxial strain." Cellulose. 16.2 (2009): 199-205. Abstract
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Ferreira, J., I. Bastos, L. Oliveira, JP Oliveira, T. Michalak, P. Pankiewicz, B. Nowacki, P. Makosa, and A. Rybarczyk. "LNA, oscillator and mixer co-design for compact RF-CMOS ISM receivers." Mixed Design of Integrated Circuits & Systems, 2009. MIXDES'09. MIXDES-16th International Conference. IEEE, 2009. 291-295. Abstract
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Oliveira, JP, L. B. Oliveira, J. Ferreira, I. Bastos, T. Michalak, P. Pankiewicz, B. Nowacki, P. Makosa, and A. Rybarczyk. "LNA, Oscillator and Mixer Co-Design Strategy Approach for RF-CMOS." Electronics and Telecommunications Quartely (2009). Abstract
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Silva, V., J. Fernandes, L. B. Oliveira, M. Véstias, and H. Neto. "Magnetic RAM Reconfigurable Array." (2009). Abstract
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Xavier, J., M. Oliveira, J. Morais, and J. Pinto. "Measurement of the shear properties of clear wood by the Arcan test." Holzforschung. 63 (2009): 217-225. Abstract
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Rivas, M. G., M. S. P. Carepo, C. S. Mota, M. Korbas, M. C. Durand, A. T. Lopes, CD Brondino, AS Pereira, GN George, A. Dolla, JJG Moura, and I. Moura. "Molybdenum Induces the Expression of a Protein Containing a New Heterometallic Mo-Fe Cluster in Desulfovibrio alaskensis." Biochemistry. 48 (2009): 873-882. AbstractWebsite

The characterization of a novel Mo-Fe protein (MorP) associated with a system that responds to Mo in Desulfovibrio alaskensis is reported. Biochemical characterization shows that MorP is a periplasmic homomultimer of high molecular weight (260 +/- 13 kDa) consisting of 16-18 monomers of 15321.1 +/- 0.5 Da. The UV/visible absorption spectrum of the as-isolated protein shows absorption peaks around 280, 320, and 570 nm with extinction coefficients of 18700, 12800, and 5000 M(-1) cm(-1), respectively. Metal content, EXAFS data and DFT calculations support the presence of a Mo-2S-[2Fe-2S]-2S-Mo cluster never reported before. Analysis of the available genomes from Desulfovibrio species shows that the MorP encoding gene is located downstream of a sensor and a regulator gene. This type of gene arrangement, called two component system, is used by the cell to regulate diverse physiological processes in response to changes in environmemtal conditions. Increase of both gene expression and protein production was observed when cells were cultured in the presence of 45 mu M molybdenum. Involvement of this system in Mo tolerance of sulfate reducing bacteria is proposed.

Silva, M., H. Machado, and AJL Phillips. "Mycosphaerella species occurring on Eucalyptus globulus in Portugal." European Journal of Plant Pathology. 125 (2009): 425-433. Abstract
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Martins, R., Leandro Raniero, Luis Pereira, Daniel Costa†, Hugo Aguas, Sonia Pereira, Leonardo Silva, A. Gonçalves, I. Ferreira, and E. Fortunato. "Nanostructured silicon and its application to solar cells, position sensors and thin film transistors." Philosophical Magazine. 89.28-30 (2009): 2699-2721. Abstract
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c Martins, R.a, Raniero Pereira Costa Aguas Pereira Silva Goncalves Ferreira Fortunato L. b L. a. "Nanostructured silicon and its application to solar cells, position sensors and thin film transistors." Philosophical Magazine. 89 (2009): 2699-2721. AbstractWebsite

This paper reports the performance of small area solar cells, 128 linear integrated position sensitive detector arrays and thin film transistors based on nanostructured silicon thin films produced by plasma-enhanced chemical vapour deposition technique, close to the onset of dusty plasma conditions, within the transition region from amorphous to microcrystalline. The small area solar cells, produced in a modified single chamber reactor, exhibited very good electrical characteristics with a conversion efficiency exceeding 9%. The 128 integrated position sensitive detector arrays, based on a similar pin structure, allow real-time 3D object imaging with a resolution higher than 90 l p/mm. The thin film transistors produced exhibited field effect mobility of 2.47 cm 2/V/s, threshold voltage of 2 V, on/off ratio larger than 10 7 and sub-threshold slopes of 0.32 V/decade, which are amongst the best results reported for this type of device. © 2009 Taylor & Francis.

Martins, R., Leandro Raniero, Luis Pereira, Daniel Costa, Hugo Aguas, Sonia Pereira, Leonardo Silva, A. Gonçalves, I. Ferreira, and E. Fortunato. "Nanostructured silicon and its application to solar cells, position sensors and thin film transistors." Philosophical Magazine. 89 (2009): 2699-2721. Abstract
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Surzhykov, A., J. P. Santos, P. Amaro, and P. Indelicato. "Negative-continuum effects on the two-photon decay rates of hydrogenlike ions." Physical Review A (Atomic, Molecular, and Optical Physics). 80 (2009): 052511. AbstractWebsite
Two-photon decay of hydrogenlike ions is studied within the framework of second-order perturbation theory, based on the relativistic Dirac's equation. Special attention is paid to the effects arising from the summation over the negative-energy (intermediate virtual) states that occur in such a framework. In order to investigate the role of these states, detailed calculations have been carried out for the 2s1/2–>1s1/2 and 2p1/2–>1s1/2 transitions in neutral hydrogen H as well as for hydrogenlike xenon Xe53+ and uranium U91+ ions. We found that for a correct evaluation of the total and energy-differential decay rates, summation over the negative-energy part of Dirac's spectrum should be properly taken into account both for high-Z and low-Z atomic systems.
Surzhykov, A., J. P. Santos, P. Amaro, and P. Indelicato. "Negative-continuum effects on the two-photon decay rates of hydrogenlike ions." Physical Review A. 80 (2009): 052511. AbstractWebsite

Two-photon decay of hydrogenlike ions is studied within the framework of second-order perturbation theory, based on the relativistic Dirac's equation. Special attention is paid to the effects arising from the summation over the negative-energy (intermediate virtual) states that occur in such a framework. In order to investigate the role of these states, detailed calculations have been carried out for the 2s1/2-->1s1/2 and 2p1/2-->1s1/2 transitions in neutral hydrogen H as well as for hydrogenlike xenon Xe53+ and uranium U91+ ions. We found that for a correct evaluation of the total and energy-differential decay rates, summation over the negative-energy part of Dirac's spectrum should be properly taken into account both for high-Z and low-Z atomic systems.

Sergeeva, V., A. Alves, and AJL Phillips. "Neofusicoccum luteum associated with leaf necrosis and fruit rot of olives in New South Wales, Australia." Phytopathologia Mediterranea. 48 (2009): 294-298. Abstract
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Mateus, O., SCR Maidment, and NA Christiansen. "A new long-necked {'}sauropod-mimic{'} stegosaur and the evolution of the plated dinosaurs." Proceedings of the Royal Society B: Biological Sciences. 276 (2009): 1815-1821. Abstract
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Sousa, P., Stanimir Valtchev, Mário Neves, and A. Rodrigues. "A New Open-Loop Control Method for Stepping Motor Driving." 2nd International Conference on Power Engineering, Energy and Electrical Drives (POWERENG'2009). 2009. 605-610.
Sousa, P., S. Valtchev, M. V. Neves, and A. L. Rodrigues. "A new open-loop control method for stepping motor driving." POWERENG 2009 - 2nd International Conference on Power Engineering, Energy and Electrical Drives Proceedings (2009): 605-610. Abstract
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Polcyn, M., L. Jacobs, O. Mateus, and A. Schulp. "New specimens of Angolasaurus bocagei and comments on the early radiations of plioplatecarpine mosasaurs. Journal of Vertebrate Paleontology." Journal of Vertebrate Paleontology. 29 (2009): 165. Abstract
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