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2014
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.

C, N, R. F, M.P.F. G, M. E, B.A. S, R.C.C. M, L. R, T. M.  2014.  Eu3+ luminescence in aluminophosphate glasses. Journal of Luminescence. 145:582-587. AbstractWebsite

With a 4f6 electronic configuration, europium ions in the trivalent charge state are known to be efficient activators in wide band gap matrices. Embedded in the aluminophosphate (Li2O–BaO–Al2O3–La2O3–P2O5) glasses the optically activated Eu3+ ions lead to intense room temperature orange/red luminescence with 16–23 Cd/m2 by using ultraviolet pumping. The as-prepared and heat treated europium doped glasses for temperatures below and above Tg were studied by room temperature Raman spectroscopy, absorption, photoluminescence excitation, temperature dependent and time dependent photoluminescence. When the samples are excited by 325 nm wavelength photons, an enhancement of the red luminescence intensity by ca. one order of magnitude was found to occur for temperatures between 14 K and 350 K, for all the doped glasses. On the other hand, by using resonant excitation on the 5L6 Eu3+ excited state (λexc~390 nm) the ion emission intensity was found to be nearly constant for temperatures up to 500 K. For higher temperatures a steeper decrease of the luminescence intensity occurs due to non-radiative competitive channels described by activation energies of ca. 235 meV and 450 meV by using 325 and 390 nm wavelength photons as excitation, respectively. The lifetime of the 5D0 level in these glasses is ca. 2.93 ms. A discussion of the thermal population and de-excitation mechanisms is performed.

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.
Roma-Rodrigues, C, Fernandes AR, Baptista PV.  2014.  Exosome in tumour microenvironment: overview of the crosstalk between normal and cancer cells. Biomed Res Int. 2014:179486.14romarodriguesbmri.pdf
Pina, AS, Batalha ÍL, Fernandes CSM, Aoki MA, Roque ACA.  2014.  Exploring the potential of magnetic antimicrobial agents for water disinfection. Water Research. 66:160–168. AbstractWebsite

Industrial and urban activities yield large amounts of contaminated groundwater, which present a major health issue worldwide. Infectious diseases are the most common health risk associated with drinking-water and wastewater remediation is a major concern of our modern society. The field of wastewater treatment is being revolutionized by new nano-scale water disinfection devices which outperform most currently available technologies. In particular, iron oxide magnetic nanoparticles (MNPs) have been widely used in environmental applications due to their unique physical–chemical properties. In this work, poly(ethylene) glycol (PEG)-coated MNPs have been functionalized with (RW)3, an antimicrobial peptide, to yield a novel magnetic-responsive support with antimicrobial activity against Escherichia coli K-12 DSM498 and Bacillus subtilis 168. The magnetic-responsive antimicrobial device showed to be able to successfully disinfect the surrounding solution. Using a rapid high-throughput screening platform, the minimal inhibitory concentration (MIC) was determined to be 500 μM for both strains with a visible bactericidal effect.

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
Conde, J, Larguinho M, Cordeiro A, Raposo LR, Costa PM, Santos S, Diniz MS, Fernandes AR, Baptista PV.  2014.  Gold-nanobeacons for gene therapy: evaluation of genotoxicity, cell toxicity and proteome profiling analysis. Nanotoxicology. 8(5):521-32.14condenantox.pdf14condenantoxsuppl.pdf
Barroso, T, Casimiro T, Ferraria A, Mattioli F, Aguiar-Ricardo A, Roque ACA.  2014.  Hybrid monoliths for magnetically-driven protein separations. Adv. Funct. Mater.. 24(28):4528–4541. AbstractWebsite

Monoliths represent powerful platforms for isolation of large molecules with high added value. This work presents a hybrid approach for antibody (Ab) capture and release. Using mostly natural polymers and clean processes, it is possible to create macroporous monoliths with well-defined porous networks, tuneable mechanical properties, and easy functionalization with a biomimetic ligand specific for Ab. Magnetic nanoparticles (MNPs) are embedded on the monolith network to confer a controlled magnetic response that facilitates and accelerates Ab recovery in the elution step. The hybrid monolithic systems prepared with agarose or chitosan/poly(vinyl alcohol) (PVA) blends exhibit promising binding capacities of Abs directly from cell-culture extracts (120 ± 10 mg Ab g−1 support) and controlled Ab magnetically-assisted elution yielding 95 ± 2% recovery. Moreover, a selective capture of mAbs directly from cell culture extracts is achieved yielding a final mAb preparation with 96% of purity.

Brás, AR, Fonseca IM, Dionísio M, Schonhals A, Affouard F, Correia NT.  2014.  Influence of Nanoscale Confinement on the Molecular Mobility of Ibuprofen. The Journal of Physical Chemistry C. 118(25):13857–13868.Website
Jorne, F, Henriques FMA, Baltazar LG.  2014.  Injection capacity of hydraulic lime grouts in different porous media. Materials and Structures (Accepted with ongoing revision).
Luis, DV, Silva J, Tomaz AI, de Almeida RF, Larguinho M, Baptista PV, Martins LM, Silva TF, Borralho PM, Rodrigues CM, Rodrigues AS, Pombeiro AJ, Fernandes AR.  2014.  Insights into the mechanisms underlying the antiproliferative potential of a Co(II) coordination compound bearing 1,10-phenanthroline-5,6-dione: DNA and protein interaction studies. J Biol Inorg Chem. 19(6):787-803.14luisjbic.pdf
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.

Figueiredo, S, Cabral R, Luis D, Fernandes AR, Baptista PV.  2014.  Integration of Gold nanoparticles and liposomes for combined anti-cancer drug delivery. Nanomedicine. (Alexander Seifalian, Achala de Mel, Deepak M. Kalaskar, Eds.)., Manchester: One Central Press (OCP)conjugation_of_gold_nanoparticles_and_liposomes_for_combined_vehicles_of_drug_delivery_in_cancer.pdf
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.
Kadar, E, Batalha ÍL, Fisher A, Roque ACA.  2014.  The interaction of polymer-coated magnetic nanoparticles with seawater. Science of The Total Environment. 487:771-777. AbstractWebsite

Laboratory studies were conducted to evaluate the interaction between bare and polymer-coated magnetic nanoparticles (MNPs) with various environmentally relevant carrying solutions including natural oceanic seawater with and without addition of algal exopolymeric substances (EPS). The MNPs were coated with three different stabilising agents, namely gum Arabic (GA-MNP), dextran (D-MNP) and carboxymethyl-dextran (CMD-MNP). The colloidal stability of the suspensions was evaluated over 48 h and we demonstrated that: (i) hydrodynamic diameters increased over time regardless of carrying solution for all MNPs except the GA-coated ones; however, the relative changes were carrying solution- and coat-dependent; (ii) polydispersity indexes of the freshly suspended MNPs are below 0.5 for all coated MNPs, unlike the much higher values obtained for the uncoated MNPs; (iii) freshly prepared MNP suspensions (both coated and uncoated) in Milli-Q (MQ) water show high colloidal stability as indicated by zeta-potential values below -30 mV, which however decrease in absolute value within 48 h for all MNPs regardless of carrying solution; (iv) EPS seems to "stabilise" the GA-coated and the CMD-coated MNPs, but not the uncoated or the D-coated MNPs, which form larger aggregates within 48 h; (v) despite this aggregation, iron (Fe)-leaching from MNPs is sustained over 48h, but remained within the range of 3-9% of the total iron-content of the initially added MNPs regardless of suspension media and capping agent. The environmental implications of our findings and biotechnological applicability of MNPs are discussed.

Carvalho, T, Augusto V, Rocha A, Lourenco NMT, Correia NT, Barreiros S, Vidinha P, Cabrita EJ, Dionisio M.  2014.  Ion Jelly Conductive Properties Using Dicyanamide-Based Ionic Liquids. Journal of Physical Chemistry B. 118(31):9445-9459. Abstract

The thermal behavior and transport properties of several ion jellys (IJs), a composite that results from the combination of gelatin with an ionic liquid (IL), were investigated by dielectric relaxation spectroscopy (DRS), differential scanning calorimetry (DSC), and pulsed field gradient nuclear magnetic resonance spectroscopy (PFG NMR). Four different ILs containing the dicyanamide anion were used: 1-butyl-3-methylimidazolium dicyanamide (BMIMDCA), 1-ethyl-3-methylimidazolium dicyanamide (EMIMDCA), 1-butyl-1-methylpyrrolidinium dicyanamide (BMPyrDCA), and 1-butylpyridinium dicyanamide (BPyDCA); the bulk ILs were also investigated for comparison. A glass transition was detected by DSC for all materials, ILs and IJs, allowing them to be classified as glass formers. Additionally, an increase in the glass transition temperature upon dehydration was observed with a greater extent for IJs, attributed to a greater hindrance imposed by the gelatin matrix after water removal, rendering the IL less mobile. While crystallization is observed for some ILs with negligible water content, it was never detected for any IJ upon thermal cycling, which persist always as fully amorphous materials. From DRS measurements, conductivity and diffusion coefficients for both cations (D+) and anions (D–) were extracted. D+ values obtained by DRS reveal excellent agreement with those obtained from PFG NMR direct measurements, obeying the same VFTH equation over a large temperature range (ΔT ≈ 150 K) within which D+ varies around 10 decades. At temperatures close to room temperature, the IJs exhibit D values comparable to the most hydrated (9%) ILs. The IJ derived from EMIMDCA possesses the highest conductivity and diffusion coefficient, respectively, 10–2 S·cm–1 and 10–10 m2·s–1. For BMPyrDCA the relaxational behavior was analyzed through the complex permittivity and modulus formalism allowing the assignment of the detected secondary relaxation to a Johari–Goldstein process. Besides the relevant information on the more fundamental nature providing physicochemical details on ILs behavior, new doorways are opened for practical applications by using IJ as a strategy to produce novel and stable electrolytes for different electrochemical devices.

Carvalho, T, Augusto V, Rocha A, Lourenço NMT, Correia NT, Barreiros S, Vidinha P, Cabrita EJ, Dionísio M.  2014.  Ion jelly conductive properties using dicyanamide-based ionic liquids. The Journal of Physical Chemistry B. 118(31):9445-9459.Website
Veigas, Bruno, Branquinho, R., Pinto, Joana, Wojcik, Pawel Jerzy, Martins, Fortunato, Baptista PV.  2014.  Ion sensing (EIS) real-time quantitative monitorization of isothermal DNA amplification. Biosensors and Bioelectronics. 52:50-55.
Costa, Veigas, Bruno, Jacob, Jorge M., Santos, GMC, Santos, GMC, Baptista, Ana Catarina, Martins, Inacio, Joao, Fortunato E.  2014.  A low cost, safe, disposable, rapid and self-sustainable paper-based platform for diagnostic testing: lab-on-paper. Nanotechnology. 25(9):12pp..
Bird, LJ, Saraiva IH, Park S, Calçada EO, Salgueiro CA, Nitschke W, Louro RO, Newman DK.  2014.  Nonredundant roles for cytochrome c2 and two high-potential iron-sulfur proteins in the photoferrotroph Rhodopseudomonas palustris TIE-1. J Bacteriol. 196(4):850-858. AbstractWebsite

The purple bacterium Rhodopseudomonas palustris TIE-1 expresses multiple small high-potential redox proteins during photoautotrophic growth, including two high-potential iron-sulfur proteins (HiPIPs) (PioC and Rpal_4085) and a cytochrome c2. We evaluated the role of these proteins in TIE-1 through genetic, physiological, and biochemical analyses. Deleting the gene encoding cytochrome c2 resulted in a loss of photosynthetic ability by TIE-1, indicating that this protein cannot be replaced by either HiPIP in cyclic electron flow. PioC was previously implicated in photoferrotrophy, an unusual form of photosynthesis in which reducing power is provided through ferrous iron oxidation. Using cyclic voltammetry (CV), electron paramagnetic resonance (EPR) spectroscopy, and flash-induced spectrometry, we show that PioC has a midpoint potential of 450 mV, contains all the typical features of a HiPIP, and can reduce the reaction centers of membrane suspensions in a light-dependent manner at a much lower rate than cytochrome c2. These data support the hypothesis that PioC linearly transfers electrons from iron, while cytochrome c2 is required for cyclic electron flow. Rpal_4085, despite having spectroscopic characteristics and a reduction potential similar to those of PioC, is unable to reduce the reaction center. Rpal_4085 is upregulated by the divalent metals Fe(II), Ni(II), and Co(II), suggesting that it might play a role in sensing or oxidizing metals in the periplasm. Taken together, our results suggest that these three small electron transfer proteins perform different functions in the cell.

Jordao, N, Cabrita L, Pina F, Branco LC.  2014.  Novel Bipyridinium Ionic Liquids as Liquid Electrochromic Devices. CHEMISTRY-A EUROPEAN JOURNAL. 20(4):3982-3988.
Maiti, BK, Maia LB, Pal K, Pakira B, Aviles T, Moura I, Pauleta SR, Nuñez JL, Rizzi AC, Brondino CD, Sarkar S, Moura JJG.  2014.  One Electron Reduced Square Planar Bis(benzene-1,2-dithiolato) Copper Dianionic Complex and Redox Switch by O2/HO-. Inorg Chem. 53:12799-12808.
Martins, P, Marques M, Coito L, Pombeiro AJ, Baptista PV, Fernandes AR.  2014.  Organometallic compounds in cancer therapy: past lessons and future directions. Anticancer Agents Med Chem. 14(9):1199-212.14martinsaamc.pdf
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]

Kardarian K, Busani T, Osório I, Domingos H, Igreja R, Franco R, Cortez J.  2014.  SINTERING OF NANOSCALE SILVER COATED TEXTILES, A NEW APPROACH TO ATTAIN CONDUCTIVE FABRICS FOR ELECTROMAGNETIC SHIELDING. Materials Chemistry and Physics. 147:815-822.