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2014
Silva, TF, Martins LM, Guedes da Silva MF, Kuznetsov ML, Fernandes AR, Silva A, Pan CJ, Lee JF, Hwang BJ, Pombeiro AJ.  2014.  Cobalt complexes with pyrazole ligands as catalyst precursors for the peroxidative oxidation of cyclohexane: X-ray absorption spectroscopy studies and biological applications. Chem Asian J. 9(4):1132-43.14silvacaj.pdf
Contreras, J, Martins R, Wojcik P, Filonovich S, Águas H, Gomes L, Fortunato E, Ferreira I.  2014.  Color sensing ability of an amorphous silicon position sensitive detector array system. Sensor Actuat. A-Phys.. 205:26-37. AbstractWebsite

The color sensing ability of a data acquisition prototype system integrating a 32 linear array of 1D amorphous silicon position sensitive detectors (PSD) was analyzed. Besides being used to reproduce a 3D profile of highly reflective surfaces, here we show that it can also differentiate primary red, green, blue (RGB) and derived colors. This was realized by using an incident beam with a RGB color combination and adequate integration times taking into account that a color surface mostly reflects its corresponding color. A mean colorimetric error of 25.7 was obtained. Overall, we show that color detection is possible via the use of this sensor array system, composed by a simpler amorphous silicon pin junction.

Simone, Zanarini, Garino, Nadia, Nair, JIJEESH RAVI, Francia, Carlotta, Wojcik PJ, Luis, Elvira, Rodrigo, Martins, Bodoardo, Silvia, Penazzi N.  2014.  Contrast Enhancement in Polymeric Electrochromic Devices Encompassing Room Temperature Ionic Liquids. International Journal of ELECTROCHEMICAL SCIENCE. 9:1650-1662.
Marcelo, F, Garcia-Martin F, Matsushita T, Sardinha J, Coelho H, Oude-Vrielink A, Koller C, André S, Cabrita EJ, Gabius H-J, Nishimura S-I, Jiménez-Barbero J, Cañada JF.  2014.  Delineating binding modes of Gal/GalNAc and structural elements of the molecular recognition of tumor-associated mucin glycopeptides by the human macrophage galactose-type lectin.. Chem. Eur. J.. 20:16147-16155. Abstract

The human macrophage galactose-type lectin (MGL) is a key physiological receptor for the carcinoma-associated Tn antigen (GalNAc-α-1-O-Ser/Thr) in mucins. NMR and modeling-based data on the molecular recognition features of synthetic Tn-bearing glycopeptides by MGL are presented. Cognate epitopes on the sugar and matching key amino acids involved in the interaction were identified by saturation transfer difference (STD) NMR spectroscopy. Only the amino acids close to the glycosylation site in the peptides are involved in lectin contact. Moreover, control experiments with non-glycosylated MUC1 peptides unequivocally showed that the sugar residue is essential for MGL binding, as is Ca(2+) . NMR data were complemented with molecular dynamics simulations and Corcema-ST to establish a 3D view on the molecular recognition process between Gal, GalNAc, and the Tn-presenting glycopeptides and MGL. Gal and GalNAc have a dual binding mode with opposite trend of the main interaction pattern and the differences in affinity can be explained by additional hydrogen bonds and CH-π contacts involving exclusively the NHAc moiety.

Madariaga, D, Martínez-Sáez N, Somovilla VJ, Coelho H, González JV, Castro-López J, Asensio JL, Jimenez-Barbero J, Busto JH, Avenoza A, Marcelo F, Hurtado-Guerrero R, Corzana F, Peregrina JM.  2014.  Detection of Tumor-Associated Glycopeptides by Lectins: the Peptide Context Modulates Carbohydrate Recognition. ACS Chem. Biol.. 10:747-56. Abstract

Tn antigen (α-O-GalNAc-Ser/Thr) is a convenient cancer biomarker that is recognized by antibodies and lectins. This work yields remarkable results for two plant lectins in terms of epitope recognition and reveals that these receptors show higher affinity for Tn antigen when it is incorporated in the Pro-Asp-Thr-Arg (PDTR) peptide region of mucin MUC1. In contrast, a significant affinity loss is observed when Tn antigen is located in the Ala-His-Gly-Val-Thr-Ser-Ala (AHGVTSA) or Ala-Pro-Gly-Ser-Thr-Ala-Pro (APGSTAP) fragments. Our data indicate that the charged residues, Arg and Asp, present in the PDTR sequence establish noteworthy fundamental interactions with the lectin surface as well as fix the conformation of the peptide backbone, favoring the presentation of the sugar moiety toward the lectin. These results may help to better understand glycopeptide-lectin interactions and may contribute to engineer new binding sites, allowing novel glycosensors for Tn antigen detection to be designed

Gouveia, JP, Dias L, Martins I, Seixas J.  2014.  Effects of renewables penetration on the security of Portuguese electricity supply. Applied Energy. 123:438–447. AbstractWebsite

The increase of renewables in power sector, together with the increase of their electricity share in final energy consumption, is changing our perception about energy security with diverse and contradictory statements. The Portuguese security of electricity supply is analyzed in this study by comparing selected indicators for 2. years before and after the high increase of onshore wind since 2005. Our goal is to find how the security of electricity supply was impacted by the penetration of renewables, taking a supply chain approach. Our analysis highlights that the penetration of renewables has decreased the energy dependence of the power sector by more than 20% between 2004 and 2011, while risks related to the concentration of natural gas suppliers and to the still-high share of fossil fuels suffering from price volatility are discussed. We observed a significant improvement in power interconnections with Spain, as well as an increase of the de-rated generation capacity margin, allowing proper management of renewable power intermittency if necessary, thereby improving power security. Although the share of intermittent renewables almost quadrupled in total installed capacity between those years, the indicators reveal an improvement in the quality of transport and distribution when delivering electricity to end-users. Although electricity prices increased, mainly due to taxes, the lack of energy efficiency is an aspect deserving improvement to alleviate the pressure on electricity security, mainly at high peak demands.

Pereira, Goncalves, Correia, Nuno, Pinto, Joana, Pereira, Martins, Fortunato E.  2014.  Electrochromic behavior of NiO thin films deposited by e-beam evaporation at room temperature. Solar Energy Materials and Solar Cells. 120:109-115.
Ferreira, JL, Gomes S, Henriques C, Borges JP, Silva JC.  2014.  Electrospinning polycaprolactone dissolved in glacial acetic acid: Fiber production, nonwoven characterization, and In Vitro evaluation. Journal of Applied Polymer Science. 131(22):41068. AbstractWebsite

The electrospinning of polycaprolactone (PCL) dissolved in glacial acetic acid and the characterization of the resultant nonwoven fiber mats is reported in this work. For comparison purposes, PCL fiber mats were also obtained by electrospinning the polymer dissolved in chloroform. Given the processing parameters chosen, results show that 14 and 17 wt % PCL solutions are not viscous enough and yield beaded fibers, 20 and 23 wt % solutions give rise to high quality fibers and 26 wt % solutions yield mostly irregular and fused fibers. The nonwoven mats are highly porous, retain the high tensile strain of PCL, and the fibers are semicrystalline. Cells adhere and proliferate equally well on all mats, irrespective of the solvent used in their production. In conclusion, mats obtained by electrospinning PCL dissolved in acetic acid are also a good option to consider when producing scaffolds for tissue engineering. Moreover, acetic acid is miscible with polar solvents, which may allow easier blending of PCL with hydrophilic polymers and therefore achieve the production of electrospun nanofibers with improved properties.

Gregório, V, Seixas J, Robinson D, Long G, Gouveia JP.  2014.  Energy Efficiency Challenges: The Linkage between the Past and the Future, for Low Carbon Historic Centres in Portugal. Urban Futures Squaring Circles: Proceedings, International Conference on Urban Futures Squaring Circles 2050. , Institute of Social Sciences of the University of Lisbon and Calouste Gulbenkian Foundation
Zubizarreta, C., Berasategui, E. G., Bayón, R., Escobar Galindo, R., Barros, R., Gaspar, Diana, Nunes, D., Calmeiro, T., Martins, Fortunato, Barriga J.  2014.  Evaluation of the optoelectronic properties and corrosion behavior of Al2O3-doped ZnO films prepared by dc pulsed magnetron sputtering. Journal of Physics D: Applied Physics. 47:13pp.
Dias, RJ, Vale TM, Lourenço JM.  2014.  Framework Support for the Efficient Implementation of Multi-Version Algorithms. Transactional Memory: Foundations, Algorithms, Tools, and Applications. (Rachid Guerraoui, Paolo Romano, Eds.).: Springer Abstractdias_vale_lourenco.pdf

Software Transactional Memory algorithms associate metadata with the memory locations accessed during a transaction’s lifetime. This metadata may be stored in an external table and accessed by way of a function that maps the address of each memory location with the table entry that keeps its metadata (this is the out-place or external scheme); or alternatively may be stored adjacent to the associated memory cell by wrapping them together (the in-place scheme). In transactional memory multi-version algorithms, several versions of the same memory location may exist. The efficient implementation of these algorithms requires a one-to-one correspondence between each memory location and its list of past versions, which is stored as metadata. In this chapter we address the matter of the efficient implementation of multi-version algorithms in Java by proposing and evaluating a novel in-place metadata scheme for the Deuce framework. This new scheme is based in Java Bytecode transformation techniques and its use requires no changes to the application code. Experimentation indicates that multi-versioning STM algorithms implemented using our new in-place scheme are in average 6× faster than when implemented with the out-place scheme.

de Almeida, MP, Pereira E, Baptista P, Gomes I, Figueiredo S, Soares L, Franco R.  2014.  Gold Nanoparticles as (bio)chemical Sensors. Comprehensive Analytical Chemistry; Gold Nanoparticles in Analytical Chemistry . (Valcárcel, M., López-Lorente, A.I., Eds.).:529–567., Amsterdam: Elsevier
Pereira, Gaspar, Diana, Guerin, D., Delattre, A., Fortunato, Martins R.  2014.  The influence of fibril composition and dimension on the performance of paper gated oxide transistors. Nanotechnology . 25:11pp.
Gouveia, JP, Bilo N, Gargiulo M, Giannakidis G, Gregório V, Duncan I, Nunes V, Robinson D, Seixas J, Valentim A.  2014.  InSMART - Integrative Smart City Planning - The case of Households in Évora. Urban Futures Squaring Circles: Proceedings, International Conference on Urban Futures Squaring Circles 2050,. , Calouste Gulbenkian Foundation: Institute of Social Sciences of the University of Lisbon and Calouste Gulbenkian Foundation Abstract

European policy has acknowledged the significance of local and regional communities for the
deployment of new low carbon technologies and their potential for sustainable energy production and use.
Several initiatives and programmes (e.g. Covenant of Mayors) have been set up to engage European cities in the
effort towards a low carbon future. At the same time, there is a critical need to improve comprehensive city
planning driven by an integrated approach and focused on cost benefit assessment towards sustainable energy
use. Hence, innovative tools and models to assess and perform in-depth analysis of the alternative measures
towards efficient energy use, will help pave the way to fully capture the potential of each city in the most
efficient (economically, socially and technically) way.
The InSMART concept brings together four European cities: Évora (Portugal), Cesena (Italy), Nottingham (UK)
and Trikala (Greece), and scientific organizations of these countries, to establish a methodology for enhancing
sustainable planning for city needs through an integrative and multidisciplinary planning approach, aiming to
developing detailed sustainable energy action plans. Such an approach will identify the optimum mix of short,
medium and long term projects and investments, addressing the efficiency of energy flows across various city
sectors with regards to economic, environmental and social criteria and will highlight priority actions.
Tools and models, like Geographic Information System, buildings models (CitySim and EnergyPlus) and
transport-based energy and carbon model, as well as a technological partial equilibrium energy model (TIMES),
are used to analyse, all the relevant sectors (buildings, industries, transports, waste and water management).
Furthermore, the cities buildings stocks are being characterized through an extensive 110-question survey
(around 410 door-to-door interviews) and will be modelled through a typology approach. Four hundred 20-
question surveys are also being carried out to evaluate transport and mobility patterns, supported on travel diaries and fulfilling different quotas for several variables (geographic location, days of the week, age and working
status) in order to assure representativeness of the data collected.
The main differences between rural and urban areas results from the building surveys and high-resolution
electricity consumption from smart meters for the Portuguese city of Évora are highlighted.

Gouveia, JP, Seixas J, Bilo N, Valentim A, Nunes V, Giannakidis G, Robinson D, Irons D, Gargiulo M.  2014.  Integrative Smart City Planning - Buildings and Mobility in Évora. 4th IAEE European Energy Conference - Sustainable Energy Policy and Strategies for Europe. , LUISS University, Rome, Italy.
Arcau, J, Andermark V, Aguiló E, Gandioso A, Moro A, Cetina M, Lima JC, Rissanen K, Ottb I, Rodríguez L.  2014.  Luminescent alkynyl-gold(I) coumarin derivatives and their biological activity. Dalton Transactions. 43:4426-4436. Abstract

Luminescent alkynyl-gold(I) coumarin derivatives and their biological activity

The synthesis and characterization of three propynyloxycoumarins are reported in this work together with the formation of three different series of gold(I) organometallic complexes. Neutral complexes are constituted by water soluble phosphines (PTA and DAPTA) which confer water solubility to them. The X-ray crystal structure of 7-(prop-2-in-1-yloxy)-1-benzopyran-2-one and its corresponding dialkynyl complex is also shown and the formation of rectangular dimers for the gold derivative in the solid state can be observed. A detailed analysis of the absorption and emission spectra of both ligands and complexes allows us to attribute the luminescent behaviour to the coumarin organic ligand. Moreover, the presence of the gold(I) metal atom seems to be responsible for an increase of coumarin phosphorescence emission. The biological activity of the complexes showed that the anionic complexes triggered strong cytotoxic effects in two different cell lines whereas the neutral gold alkynyl complexes led to lower effects against tumor cell growth. Thioredoxin reductase (TrxR) inhibition was very strong in the case of the neutral complexes (IC50 values below 0.1 μM) but moderate for the anionic complexes (IC50 values above 0.8 μM).

Gaspar, Diana, Fernandes, de Oliveira, Pedro Guedes, Fernandes, Grey, P., Pontes, R. V., Pereira, Martins, Godinho, M. H., Fortunato E.  2014.  Nanocrystalline cellulose applied simultaneously as the gate dielectric and the substrate in flexible field effect transistors. Nanotechnology. 25(9)
Catalao, MJ, Figueiredo J, Henriques MX, Gomes JP, Filipe SR.  2014.  Optimization of fluorescent tools for cell biology studies in Gram-positive bacteria. PLoS One. 9:e113796.
Dourado, CG, Duarte MA, Grosso AR, Bastos-Silveira C, Marrero P, Oliveira P, Paulo OS, Dias D.  2014.  Phylogenetic origin of the endemic pigeons from Madeira (Columba trocaz) and Azores Islands (Columba palumbus azorica). Journal of Ornithology. 155:71–82., Number 1 Abstract

This study addresses for the first time the issue of pigeon (genus Columba) phylogeny within the archipelagos of Madeira ( Columba trocaz) and Azores ( C. palumbus azorica), located in the singular biogeographic area of Macaronesia. The phylogeny of these endemic pigeons was inferred based on mitochondrial (cytochrome b and cytochrome c oxidase I) and nuclear ($\beta$-fibrinogen intron 7) genetic markers through multiple approaches. Despite the non-monophyletic pattern for the insular endemic species recovered in the phylogenies, topology tests presented somewhat different results. C. trocaz, the Madeiran endemic species, clustered strongly with the Canarian endemic C. bollii, and these two are thus more closely related to each other than C. bollii to C. junoniae, the other endemic species of Canary Islands, which seems to have diverged independently. Moreover, C. trocaz was found to be phylogenetically closer to C. bollii than to C. palumbus from mainland Europe and Azores Islands. No genetic differentiation was found between the continental C. p. palumbus and the endemic C. p. azorica, which suggests a relatively recent colonisation event of the Azores Islands. (English) [ABSTRACT FROM AUTHOR]

Teixeira, SS, Graça MPF, Dionísio M, Ilcikova M, Mosnacek J, Spitalsky Z, Krupa I, Costa LC.  2014.  Self-standing elastomeric composites based on lithium ferrites and their dielectric behavior. Journal of Applied Physics. 116:224102(1-8).Website
Fernandes, DM, Granadeiro CM, de M. PSP, Grazina R, Moura JJG, Silva P, Almeida Paz FA, Cunha-Silva L, Balula SS, Freire C.  2014.  SiW11Fe@MIL-101(Cr) composite: A novel and versatile electrocatalyst. ChemElectroChem. 1:1293-1300.
Pina, AS, Guilherme M, Pereira AS, Fernandes CSM, Branco RJF, Lowe CR, Roque ACA.  2014.  A tailor made affinity pair “tag-receptor” for the purification of fusion proteins. ChemBioChem. 15(10):1423-35. AbstractWebsite

A novel affinity “tag–receptor” pair was developed as a generic platform for the purification of fusion proteins. The hexapeptide RKRKRK was selected as the affinity tag and fused to green fluorescent protein (GFP). The DNA fragments were designed, cloned in Pet-21c expression vector and expressed in E. coli host as soluble protein. A solid-phase combinatorial library based on the Ugi reaction was synthesized: 64 affinity ligands displaying complementary functionalities towards the designed tag. The library was screened by affinity chromatography in a 96-well format for binding to the RKRKRK-tagged GFP protein. Lead ligand A7C1 was selected for the purification of RKRKRK fusion proteins. The affinity pair RKRKRK-tagged GFP with A7C1 emerged as a promising solution (Ka of 2.45×105 M−1). The specificity of the ligand towards the tag was observed experimentally and theoretically through automated docking and molecular dynamics simulations.

Gavara, R, Gago S, Jordao N, Pina F.  2014.  4 '-Carboxy-7-hydroxyflavylium. A Multistate System Involving Twelve Species Reversibly lnterconverted by pH and Light Stimuli. Journal of Physical Chemistry A. 118:4723-4731., Number 26 AbstractWebsite
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F. S. Silva, T, M. D. R. S. Martins L, Guedes da Silva FMC, Kuznetsov ML, Fernandes AR, Silva A, Pan C-J, Lee J-F, Hwang B-J, J. L. Pombeiro A.  2014.  Cobalt Complexes with Pyrazole Ligands as Catalyst Precursors for the Peroxidative Oxidation of Cyclohexane: X-ray Absorption Spectroscopy Studies and Biological Applications. Chemistry – An Asian Journal. 9:1132–1143., Number 4: WILEY-VCH Verlag AbstractWebsite
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{Peixoto de Almeida}, M, Pereira E, Baptista P, Gomes I, Figueiredo S, Soares L, Franco R.  2014.  Gold Nanoparticles as (Bio)Chemical Sensors. Comprehensive Analytical Chemistry. 66:529–567.: Elsevier Abstract

This chapter focuses on several sensing strategies and major recent advances in the use of gold nanoparticles in (bio)sensing of chemical and biological analytes. A brief introduction is presented on relevant properties of gold nanoparticles for sensing, the main types of (bio)chemical sensors, and the main detection techniques, followed by subsections according to sensing methodologies. These include colorimetric sensing and the biobarcode assay, fluorometric-based methods, electric and electrochemical sensing, and, last, more recent and advanced methodologies such as surface plasmon resonance and Raman-based sensors. In closing, relevance is given to advanced methods, featuring extremely high sensitivity and selectivity, down to single-molecule detection. Anisotropic gold nanoparticles have a special role in future developments.

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