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2013
Mendes, Ana, Daniel Aelenei, L. Aguiar, C. Pereira, M. Neves, Silva P, Azevedo Susana, D. Mendes, L. Guimar, and J. Teixeira. "The Effects on Health of Indoor Air Quality and Thermal Comfort In Elderly Care Centers." 2nd International Conference on Occupational & Environmental Toxicology. 2013. Abstract
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Neagu, B., E. R. Neagu, R. Igreja, and C. Dias. "Electric Field Distribution Around the Deep Brain Stimulation Electrode Inferred from Dielectric Measurements." Advanced Materials Forum Vi, Pts 1 and 2. Eds. AMP Pinto, and AS Pouzada. Vol. 730-732. Materials Science Forum, 730-732. 2013. 26-31. Abstract
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Neagu, B., E. R. Neagu, R. Igreja, C. Dias, AMP Pinto, and AS Pouzada. "Electric Field Distribution Around the Deep Brain Stimulation Electrode Inferred from Dielectric Measurements." Advanced Materials Forum Vi, Pts 1 and 2. 730-732 (2013): 26-31. Abstract
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Aelenei, Daniel, Susana Azevedo, João Viegas, Ana Mendes, Ana Luisa Papoila, Manuela Cano, Pedro Martins, and Nuno Neuparth. "Environment and Health in Children Day Care Centres in Portugal - results from phase II on the ventilation characteristics of 16 schools." CLIMA 2013. 978-80-260-4001-9. 2013. Abstract
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Madeira, D., L. Narciso, H. N. Cabral, C. Vinagre, and M. S. Diniz. "Influence of temperature in thermal and oxidative stress responses in estuarine fish." Comparative Biochemistry and Physiology - A Molecular and Integrative Physiology. 166 (2013): 237-243. AbstractWebsite
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Mota, Pedro. "On a Continuous-Time Stock Price Model with Two Mean Reverting Regimes." Advances in Regression, Survival Analysis, Extreme Values, Markov Processes and Other Statistical Applications. Eds. João Lita da Silva, Frederico Caeiro, Isabel Natário, and Carlos A. Braumann. Berlin, Heidelberg: Springer Berlin Heidelberg, 2013. 297-305. Abstract

Motivated by the need to describe regime switching in stock prices, we introduce and study a stochastic process in continuous time with two regimes and one threshold driving the change in regimes. When the difference between the regimes is simply given by different sets of real-valued parameters for the drift and diffusion coefficients, we show that there are consistent estimators for the threshold as long as we know how to classify a given observation of the process as belonging to one of the two regimes.

Araújo, Andreia, Raquel Barros, Tiago Mateus, Diana Gaspar, Nuno Neves, António Vicente, Sergej A. Filonovich, Pedro Barquinha, Elvira Fortunato, Ana M. Ferraria, and others. "Role of a disperse carbon interlayer on the performances of tandem a-Si solar cells." Science and Technology of Advanced Materials. 14 (2013): 045009. Abstract
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Neu, Ursula, Stacy-Ann A. Allen, Barbel S. Blaum, Yan Liu, Martin Frank, Angelina S. Palma, Luisa J. Stroh, Ten Feizi, Thomas Peters, Walter J. Atwood, and Thilo Stehle. "A Structure-Guided Mutation in the Major Capsid Protein Retargets BK Polyomavirus." PLoS pathogens. 9 (2013): e1003688. Abstract
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Neu, Ursula, Zaigham Mahmood Khan, Benjamin Schuch, Angelina S. Palma, Yan Liu, Michael Pawlita, Ten Feizi, and Thilo Stehle. "Structures of B-Lymphotropic Polyomavirus VP1 in Complex with Oligosaccharide Ligands." PLoS pathogens. 9 (2013): e1003714. Abstract
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Santos, Alcemir, Felipe Nunes Gaia, Eduardo Figueiredo, Pedro Santos Neto, and João Araújo. "Test-based SPL extraction: an exploratory study." SAC. 2013. 1031-1036. Abstract
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Santos, R., J. Loureiro, A. Nogueira, E. Elangovan, JV Pinto, JP Veiga, T. Busani, E. Fortunato, R. Martins, and I. Ferreira. "Thermoelectric properties of V2O5 thin films deposited by thermal evaporation." Applied Surface Science. 282 (2013): 590-594. Abstract
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Santos, R., J. Loureiro, A. Nogueira, E. Elangovan, JV Pinto, JP Veiga, T. Busani, E. Fortunato, R. Martins, and I. Ferreira. "Thermoelectric properties of V< sub> 2 O< sub> 5 thin films deposited by thermal evaporation." Applied Surface Science (2013). Abstract
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Santos, R., J. Loureiro, A. Nogueira, E. Elangovan, JV Pinto, JP Veiga, T. Busani, E. Fortunato, R. Martins, and I. Ferreira. "Thermoelectric properties of V< sub> 2 O< sub> 5 thin films deposited by thermal evaporation." Applied Surface Science. 282 (2013): 590-594. Abstract
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Lanca, M. C., I. Cunha, J. P. Marques, E. R. Neagu, L. Gil, C. J. Dias, and J. N. Marat-Mendes. "Water Content Control To Improve Space Charge Storage in a Cork Derivative." Advanced Materials Forum Vi, Pts 1 and 2. Eds. AMP Pinto, and AS Pouzada. Vol. 730-732. Materials Science Forum, 730-732. 2013. 395-400. Abstract
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Lanca, M. C., I. Cunha, J. P. Marques, E. R. Neagu, L. Gil, C. J. Dias, J. N. Marat-Mendes, AMP Pinto, and AS Pouzada. "Water Content Control To Improve Space Charge Storage in a Cork Derivative." Advanced Materials Forum Vi, Pts 1 and 2. 730-732 (2013): 395-400. Abstract
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Nandy, Suman, Gonçalo Gonçalves, Joana Vaz Pinto, Tito Busani, Vitor Figueiredo, Lu\'ıs Pereira, Rodrigo Ferrão {Paiva Martins}, and Elvira Fortunato. "{Current transport mechanism at metal-semiconductor nanoscale interfaces based on ultrahigh density arrays of p-type NiO nano-pillars.}." Nanoscale. 5 (2013): 11699-709. AbstractWebsite

The present work focuses on a qualitative analysis of localised I-V characteristics based on the nanostructure morphology of highly dense arrays of p-type NiO nano-pillars (NiO-NPs). Vertically aligned NiO-NPs have been grown on different substrates by using a glancing angle deposition (GLAD) technique. The preferred orientation of as grown NiO-NPs was controlled by the deposition pressure. The NiO-NPs displayed a polar surface with a microscopic dipole moment along the (111) plane (Tasker's type III). Consequently, the crystal plane dependent surface electron accumulation layer and the lattice disorder at the grain boundary interface showed a non-uniform current distribution throughout the sample surface, demonstrated by a conducting AFM technique (c-AFM). The variation in I-V for different points in a single current distribution grain (CD-grain) has been attributed to the variation of Schottky barrier height (SBH) at the metal-semiconductor (M-S) interface. Furthermore, we observed that the strain produced during the NiO-NPs growth can modulate the SBH. Inbound strain acts as an external field to influence the local electric field at the M-S interface causing a variation in SBH with the NPs orientation. This paper shows that vertical arrays of NiO-NPs are potential candidates for nanoscale devices because they have a great impact on the local current transport mechanism due to its nanostructure morphology.

Gawande, Manoj B., Anuj K. Rathi, Paula S. Branco, T. M. Potewar, Alexandre Velhinho, Isabel D. Nogueira, Alexander Tolstoguzov, Amjad C. A. Ghumman, and Orlando M. N. D. Teodoro. "{Nano-MgO-ZrO2 Mixed Metal oxides: Characterization by SIMS and application in the reduction of carbonyl compounds and in multicomponent reactions}." RSC Advances. 3 (2013): 3611-3617. Abstract

A nano-sized Magnesia–Zirconia (nano-MgO–ZrO2) catalyst was prepared by a simple ultradilution co-precipitation method and by using inexpensive precursors. The nano-MgO–ZrO2 was extensively characterized by SIMS together with other analytical techniques such as X-ray diffraction (XRD) and transmission electron microscopy (TEM). The nano-MgO–ZrO2 catalyst proved to be very efficient for the reduction of carbonyl compounds and multicomponent reactions under mild reaction conditions. The recyclability and reusability of the nano-MgO–ZrO2 catalyst has been tested.

Parthiban, Shanmugam, Elamurugu Elangovan, Pradipta K. Nayak, Alexandra Gonçalves, Daniela Nunes, Lu\'ıs Pereira, Pedro Barquinha, Tito Busani, Elvira Fortunato, and Rodrigo Martins. "{Performances of Microcrystalline Zinc Tin Oxide Thin-Film Transistors Processed by Spray Pyrolysis}." 9 (2013): 825-831. Abstract
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2012
Gomes, Gabriela M. M., Ricardo Aguas, Joao S. Lopes, Marta C. Nunes, Carlota Rebelo, Paula Rodrigues, and Claudio J. Struchiner. "How host heterogeneity governs tuberculosis reinfection?" PROCEEDINGS OF THE ROYAL SOCIETY B-BIOLOGICAL SCIENCES. 279 (2012): 2473-2478. Abstract

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Pereira, AS, C. G. Timoteo, M. Guilherme, F. Folgosa, S. G. Naik, A. G. Duarte, BH HUYNH, and P. Tavares. "Spectroscopic evidence for and characterization of a trinuclear ferroxidase center in bacterial ferritin from Desulfovibrio vulgaris Hildenborough." Journal of the American Chemical Society. 134 (2012): 10822-32. AbstractWebsite

Ferritins are ubiquitous and can be found in practically all organisms that utilize Fe. They are composed of 24 subunits forming a hollow sphere with an inner cavity of ~80 A in diameter. The main function of ferritin is to oxidize the cytotoxic Fe(2+) ions and store the oxidized Fe in the inner cavity. It has been established that the initial step of rapid oxidation of Fe(2+) (ferroxidation) by H-type ferritins, found in vertebrates, occurs at a diiron binding center, termed the ferroxidase center. In bacterial ferritins, however, X-ray crystallographic evidence and amino acid sequence analysis revealed a trinuclear Fe binding center comprising a binuclear Fe binding center (sites A and B), homologous to the ferroxidase center of H-type ferritin, and an adjacent mononuclear Fe binding site (site C). In an effort to obtain further evidence supporting the presence of a trinuclear Fe binding center in bacterial ferritins and to gain information on the states of the iron bound to the trinuclear center, bacterial ferritin from Desulfovibrio vulgaris (DvFtn) and its E130A variant was loaded with substoichiometric amounts of Fe(2+), and the products were characterized by Mossbauer and EPR spectroscopy. Four distinct Fe species were identified: a paramagnetic diferrous species, a diamagnetic diferrous species, a mixed valence Fe(2+)Fe(3+) species, and a mononuclear Fe(2+) species. The latter three species were detected in the wild-type DvFtn, while the paramagnetic diferrous species was detected in the E130A variant. These observations can be rationally explained by the presence of a trinuclear Fe binding center, and the four Fe species can be properly assigned to the three Fe binding sites. Further, our spectroscopic data suggest that (1) the fully occupied trinuclear center supports an all ferrous state, (2) sites B and C are bridged by a mu-OH group forming a diiron subcenter within the trinuclear center, and (3) this subcenter can afford both a mixed valence Fe(2+)Fe(3+) state and a diferrous state. Mechanistic insights provided by these new findings are discussed and a minimal mechanistic scheme involving O-O bond cleavage is proposed.

Parreira, P., E. Torres, C. Nunes, Nunes C. de Carvalho, G. Lavareda, A. Amaral, and M. J. Brites. "Dye-sensitized 1D anatase TiO2 nanorods for tunable efficient photodetection in the visible range." SENSORS AND ACTUATORS B-CHEMICAL. 161 (2012): 901-907. Abstract

TiO2 films with enhanced photosensitivity were deposited on alkali free glass substrates without intentional substrate heating by pulsed DC magnetron reactive sputtering with an average thickness of about 2 mu m. Three dyes, commercial N719 and two new organic dyes were impregnated in order to control the optical spectral selectivity of such films. The type of dye used proved to dramatically influence the device's response to radiation pulses. The practical breakthrough is the use of different dyes according to the region of the electromagnetic spectrum one wants to detect. Devices with photocurrent 6 orders of magnitude higher than the dark current (from similar to 2 x 10(-12) to 2 x 10(-6) A for a 100 V bias) were fabricated with a spectral response within the visible range of the electromagnetic spectrum. In addition, this approach is likely to allow for the fabrication of hybrid photodetectors on cheap heat sensible flexible polymeric substrates. (C) 2011 Elsevier B.V. All rights reserved.

Parreira, P., E. Torres, C. Nunes, C. Nunes de Carvalho, G. Lavareda, A. Amaral, and M. J. Brites. "Dye-sensitized 1D anatase TiO2 nanorods for tunable efficient photodetection in the visible range." SENSORS AND ACTUATORS B-CHEMICAL. 161 (2012): 901-907. Abstract

TiO2 films with enhanced photosensitivity were deposited on alkali free glass substrates without intentional substrate heating by pulsed DC magnetron reactive sputtering with an average thickness of about 2 mu m. Three dyes, commercial N719 and two new organic dyes were impregnated in order to control the optical spectral selectivity of such films. The type of dye used proved to dramatically influence the device's response to radiation pulses. The practical breakthrough is the use of different dyes according to the region of the electromagnetic spectrum one wants to detect. Devices with photocurrent 6 orders of magnitude higher than the dark current (from similar to 2 x 10(-12) to 2 x 10(-6) A for a 100 V bias) were fabricated with a spectral response within the visible range of the electromagnetic spectrum. In addition, this approach is likely to allow for the fabrication of hybrid photodetectors on cheap heat sensible flexible polymeric substrates. (C) 2011 Elsevier B.V. All rights reserved.

AFR, Pimenta, Baptista AC, Carvalho T, Brogueira P, Lourenco NMT, Afonso CAM, Barreiros S, Vidinha P, and Borges JP. "Electrospinning of Ion Jelly fibers." MATERIALS LETTERS. 83 (2012): 161-164. Abstract
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MB, Gawande, Rathi AK, Branco PS, Nogueira ID, Velhinho A, Shrikhande JJ, Indulkar UU, Jayaram RV, Ghumman CAA, Bundaleski N, and Teodoro OMND. "Regio- and Chemoselective Reduction of Nitroarenes and Carbonyl Compounds over Recyclable Magnetic Ferrite-Nickel Nanoparticles (Fe3O4-Ni) by Using Glycerol as a Hydrogen Source." CHEMISTRY-A EUROPEAN JOURNAL. 18 (2012): 12628-12632. Abstract
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Inês, Cunha, Marques João Paulo, Gil Luís, Neagu E. R., Dias C. J., Marat-Mendes J. N., and Lança M. C. "Water Content Control to Improve Space Charge Storage in a Cork Derivative." Materials Science Forum. 2012. 395-400. Abstract
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