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2014
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, aug. Nanotoxicology. 8:521–532., Number 5: Informa Healthcare Abstract

Antisense therapy is a powerful tool for post-transcriptional gene silencing suitable for down-regulating target genes associated to disease. Gold nanoparticles have been described as effective intracellular delivery vehicles for antisense oligonucleotides providing increased protection against nucleases and targeting capability via simple surface modification. We constructed an antisense gold-nanobeacon consisting of a stem-looped oligonucleotide double-labelled with 3′-Cy3 and 5′-Thiol-C6 and tested for the effective blocking of gene expression in colorectal cancer cells. Due to the beacon conformation, gene silencing was directly detected as fluorescence increases with hybridisation to target, which can be used to assess the level of silencing. Moreover, this system was extensively evaluated for the genotoxic, cytotoxic and proteomic effects of gold-nanobeacon exposure to cancer cells. The exposure was evaluated by two-dimensional protein electrophoresis followed by mass spectrometry to perform a proteomic profile and 3-(4,5-Dimethylthiazol-2- Yl)-2,5-Diphenyltetrazolium Bromide (MTT) assay, glutathione-S-transferase assay, micronucleus test and comet assay to assess the genotoxicity. This integrated toxicology evaluation showed that the proposed nanotheranostics strategy does not exhibit significant toxicity, which is extremely relevant when translating into in vivo systems.

Santos, TG, Miranda RM, De Carvalho CCCR.  2014.  A new NDT technique based on bacterial cells to detect micro surface defects, 2014. NDT and E International. 63:43-49. AbstractWebsite
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Dhadge, VL, Hussain A, Azevedo AM, Aires-Barros MR, Roque ACA.  2014.  Boronic acid-modified magnetic materials for antibody purification. J. R. Soc. Interface. 11(91):20130875. AbstractWebsite

Aminophenyl boronic acids can form reversible covalent ester interactions with cis-diol-containing molecules, serving as a selective tool for binding glycoproteins as antibody molecules that possess oligosaccharides in both the Fv and Fc regions. In this study, amino phenyl boronic acid (APBA) magnetic particles (MPs) were applied for the magnetic separation of antibody molecules. Iron oxide MPs were firstly coated with dextran to avoid non-specific binding and then with 3-glycidyloxypropyl trimethoxysilane to allow further covalent coupling of APBA (APBA_MP). When contacted with pure protein solutions of human IgG (hIgG) and bovine serum albumin (BSA), APBA_MP bound 170 ± 10 mg hIgG g−1 MP and eluted 160 ± 5 mg hIgG g−1 MP, while binding only 15 ± 5 mg BSA g−1 MP. The affinity constant for the interaction between hIgG and APBA_MP was estimated as 4.9 × 105 M−1 (Ka) with a theoretical maximum capacity of 492 mg hIgG adsorbed g−1 MP (Qmax), whereas control particles bound a negligible amount of hIgG and presented an estimated theoretical maximum capacity of 3.1 mg hIgG adsorbed g−1 MP (Qmax). APBA_MPs were also tested for antibody purification directly from CHO cell supernatants. The particles were able to bind 98% of IgG loaded and to recover 95% of pure IgG (purity greater than 98%) at extremely mild conditions.

Viciosa, MT, Alves NM, Oliveira T, Dionísio M, Mano JF.  2014.  Confinement Effects on the Dynamic Behavior of Poly(D,L-lactic acid) upon Incorporation in alpha-Cyclodextrin. the Journal of Physical Chemistry B. 118(24):6972–6981.Website
Johnston, EM, Dell'Acqua S, Ramos S, Pauleta SR, Moura I, Solomon EI.  2014.  Determination of the active form of the tetranuclear copper sulfur cluster in nitrous oxide reductase. J Am Chem Soc. 136:614–617.
Rueff, A-S, Chastanet A, Dominguez-Escobar J, Yao Z, Yates J, Prejean M-V, Delumeau O, P. Noirot, Wedlich-Soldner R, Filipe SR, Carballido-Lopez R.  2014.  An early cytoplasmic step of peptidoglycan synthesis is associated to MreB in Bacillus subtilis. Mol. Microbiol. 91:348-362.
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.

Dantas, JM, Morgado L, Catarino T, Kokhan O, Pokkuluri PR, Salgueiro CA.  2014.  Evidence for interaction between the triheme cytochrome PpcA from Geobacter sulfurreducens and anthrahydroquinone-2,6-disulfonate, an analog of the redox active components of humic substances. Biochim Biophys Acta. 1837(6):750-760. AbstractWebsite

The bacterium Geobacter sulfurreducens displays an extraordinary respiratory versatility underpinning the diversity of electron donors and acceptors that can be used to sustain anaerobic growth. Remarkably, G. sulfurreducens can also use as electron donors the reduced forms of some acceptors, such as the humic substance analog anthraquinone-2,6-disulfonate (AQDS), a feature that confers environmentally competitive advantages to the organism. Using UV-visible and stopped-flow kinetic measurements we demonstrate that there is electron exchange between the triheme cytochrome PpcA from Gs and AQDS. 2D-(1)H-(15)N HSQC NMR spectra were recorded for (15)N-enriched PpcA samples, in the absence and presence of AQDS. Chemical shift perturbation measurements, at increasing concentration of AQDS, were used to probe the interaction region and to measure the binding affinity of the PpcA-AQDS complex. The perturbations on the NMR signals corresponding to the PpcA backbone NH and heme substituents showed that the region around heme IV interacts with AQDS through the formation of a complex with a definite life time in the NMR time scale. The comparison of the NMR data obtained for PpcA in the presence and absence of AQDS showed that the interaction is reversible. Overall, this study provides for the first time a clear illustration of the formation of an electron transfer complex between AQDS and a G. sulfurreducens triheme cytochrome, shedding light on the electron transfer pathways underlying the microbial oxidation of humics.

Dhadge, VL, Morgado PI, Freitas F, Reis MA, Azevedo AM, Aires-Barros R, Roque ACA.  2014.  An extracellular polymer at the interface of magnetic bioseparations. Journal of the Royal Society Interface. 11(100):20140743. AbstractWebsite

FucoPol, a fucose-containing extracellular polysaccharide (EPS) produced by bacterium Enterobacter A47 using glycerol as the carbon source, was employed as a coating material for magnetic particles (MPs), which were subsequently functionalized with an artificial ligand for the capture of antibodies. The performance of the modified MPs (MP–EPS-22/8) for antibody purification was investigated using direct magnetic separation alone or combined with an aqueous two-phase system (ATPS) composed of polyethylene glycol (PEG) and dextran. In direct magnetic capturing, and using pure protein solutions of human immunoglobulin G (hIgG) and bovine serum albumin (BSA), MP–EPS-22/8 bound 120 mg hIgG g−1 MPs, whereas with BSA only 10 ± 2 mg BSA g−1 MPs was achieved. The hybrid process combining both the ATPS and magnetic capturing leads to a good performance for partitioning of hIgG in the desired phase as well as recovery by the magnetic separator. The MPs were able to bind 145 mg of hIgG g−1 of particles which is quite high when compared with direct magnetic separation. The theoretical maximum capacity was calculated to be 410 ± 15 mg hIgG adsorbed g−1 MPs with a binding affinity constant of 4.3 × 104 M−1. In multiple extraction steps, the MPs bound 92% of loaded hIgG with a final purity level of 98.5%. The MPs could easily be regenerated, recycled and re-used for five cycles with only minor loss of capacity. FucoPol coating allowed both electrostatic and hydrophobic interactions with the antibody contributing to enhance the specificity for the targeted products.

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.

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
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.
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
Dall`Agnol, L, Cordas C, Moura JJG.  2014.  Influence of respiratory substrate in carbon steel corrosion by a sulphate reducing prokaryote model organism. Bioelectrochemistry. 97:43-51.
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.

Sanguino P, Monteiro T, Marques F, Dias CJ, Igreja R, Franco R.  2014.  INTERDIGITATED CAPACITIVE IMMUNOSENSORS WITH PVDF IMMOBILIZATION LAYERS. IEEE SENSORS JOURNAL. 14(4):1260-1265.
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
Dhadge, VL, Rosa S, Azevedo A, Aires-Barros R, Roque ACA.  2014.  Magnetic Aqueous Two Phase Fishing: An Hybrid Process Technology for Antibody Purification. J. Chromatogr. A. 1339:59-64. AbstractWebsite

The potential to combine aqueous two-phase extraction (ATPE) with magnetic separation was here investigated with the aim of developing a selective non-chromatographic method for the purification of antibodies from cell culture supernatants. Aqueous two-phase systems (ATPS) composed of polyethylene glycol (PEG) and dextran were supplemented with several surface modified magnetic particles (MPs) at distinct salt concentrations. The partition of pure human IgG in the upper and lower phases as well as the amount adsorbed at the MPs surface was investigated, indicating that MPs coated with dextran and gum Arabic established the lowest amount of non-specific interactions. The binding capacity of gum arabic coated particles modified with aminophenyl boronic acid (GA-APBA-MP) was were found to be excellent in combination with the ATPS system, yielding high yields of antibody recovery (92%) and purity (98%) from cell culture supernatants. The presence of MPs in the ATPS was found to speed up phase separation (from 40 to 25 min), to consume a lower amount of MPs (half of the amount needed in magnetic fishing) and to increase the yield and purity of a mAb purified from a cell culture supernatant, when compared with ATPE or magnetic fishing processes alone.

Loureiro, J, Santos JR, Nogueira A, Wyczisk F, Divay L, Reparaz S, Alzina F, Torres CMS, Cuffe J, Montemor F, Martins R, Ferreira I.  2014.  Nanostructured p-type Cr/V2O5 thin films with boosted thermoelectric properties. J. Mater. Chem. A. 2(18):6456-6462. AbstractWebsite

The urgent need for non-toxic and abundant thermoelectric materials has become a significant motivation to improve the figures of merit of metal oxides in order to remove the barrier towards their widespread use for thermoelectric applications. Here we show the influence of a Cr layer in boosting the thermoelectric properties of vanadium pentoxide (V2O5) thin films, deposited by thermal evaporation and annealed at 500 °C. The Cr to V2O5 thickness ratio controls the morphological and thermoelectric properties of the thin films produced. The optimized Seebeck coefficient and power factor values at room temperature are +50 μV K−1 and 7.9 × 10−4 W m−1 K−2, respectively. The nanograin structure of the films is responsible for an improvement in the electrical conductivity up to 3 × 105 (Ω m)−1 with a typical thermal conductivity of 1.5 W m−1 K−1. These results combine to yield promising p-type thermoeletric CrV2O5 thin films with a ZT of 0.16 at room temperature.

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]

Sousa, D, Lourenço JM, Ferreira C, Dias RJ.  2014.  Preventing Atomicity Violations with Contracts. , Number UNL-2014: Faculdade de Ciências e Tecnologia, Universidade Nova de Lisboa Abstract2014-sousa.pdf

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Dantas, JM, Morgado L, Marques AC, Salgueiro CA.  2014.  Probing the effect of ionic strength on the functional robustness of the triheme cytochrome PpcA from Geobacter sulfurreducens: a contribution for optimizing biofuel cell's power density. J Phys Chem B. 118(43):12416-12425. AbstractWebsite

The increase of conductivity of electrolytes favors the current production in microbial fuel cells (MFCs). Adaptation of cell cultures to higher ionic strength is a promising strategy to increase electricity production. The bacterium Geobacter sulfurreducens is considered a leading candidate for MFCs. Therefore, it is important to evaluate the impact of the ionic strength on the functional properties of key periplasmic proteins that warrants electron transfer to cell exterior. The effect of the ionic strength on the functional properties of triheme cytochrome PpcA, the most abundant periplasmic cytochrome in G. sulfurreducens, was investigated by NMR and potentiometric methods. The redox properties of heme IV are the most affected ones. Chemical shift perturbation measurements on the backbone NMR signals, at increasing ionic strength, also showed that the region close to heme IV is the most affected due to the large number of positively charged residues, which confer a highly positive electrostatic surface around this heme. The shielding of these positive charges at high ionic strength explain the observed decrease in the reduction potential of heme IV and shows that PpcA was designed to maintain its functional mechanistic features even at high ionic strength.

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
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.
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