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2016
Aroso, IM, Silva JC, Mano F, Ferreira ASD, Dionísio M, Sá-Nogueira I, Barreiros S, Reis RL, Paiva A, Duarte ARC.  2016.  Dissolution enhancement of active pharmaceutical ingredients by therapeutic deep eutectic systems. European Journal of Pharmaceutics and Biopharmaceutics. 98:57-66.Website
Echeverria, C, Fernandes SN, Almeida PL, Godinho MH.  2016.  Effect of cellulose nanocrystals in a cellulosic liquid crystal behaviour under low shear (regime I): Structure and molecular dynamics. European Polymer Journal. 84:675-684. AbstractWebsite

In the field of cellulosic liquid crystals, attempts to establish the relationship between structure/properties have been developed. Above a critical concentration in an aqueous solution, hydroxypropylcellulose self-assembles in order to form cholesteric liquid crystal phases (LC-HPC). In this work we aim to understand how the incorporation of a low content of cellulose nanocrystals (CNC) within LC-HPC/H2O (50 wt%), could influence the behaviour of the system when subjected to low shear rates, where the cholesteric phase still persists. The analysis of the deuterium spectrum and the T2 (transversal relaxation) values confirm that the mobility of LC-HPC at low shear rates is restricted due to CNC, and consequently so is the flow of the cholesteric polydomains. These effects are more evident in the LC-HPC sample containing 2 wt% of CNC; besides needing more strain units to induce some degree of order, the achieved degree of order is recovered faster when compared to the reference sample.

Pedroso, HA, Silveira CM, Almeida RM, Almeida A, Besson S, Moura I, Moura JJG, Almeida MG.  2016.  Electron transfer and docking between cytochrome cd1 nitrite reductase and different redox partners - A comparative study. Biochim Biophys Acta. 1857:1412-142104.279.Website
Cruz, J, Figueiredo E, Corregidor V, Girginova PI, Alves LC, Cruz C, Silva RJC, Liritzis I.  2016.  First results on radiometric dating of metals by alpha spectrometry. microchemj124-608-2016.pdf
Mello, RLS, Almeida T.  2016.  Intersecções entre os campos da Arte e da Ciência. Mouseion: Revista do Museu e Arquivo Histórico de Salle. (ISSN: 1981-7207):39-51.Website
Granadeiro, CM, Ribeiro SO, Kaczmarek AM, Cunha-Silva L, Almeida PL, Gago S, Van Deun R, de Castro B, Balula SS.  2016.  A novel red emitting material based on polyoxometalate@ periodic mesoporous organosilica. Microporous and Mesoporous Materials. 234:248-256. AbstractWebsite

The first lanthanopolyoxometalate-supported bifunctional periodic mesoporous organosilica (BPMO) composite is here reported. The incorporation of decatunsgstoeuropate anions ([Eu(W5O18)2]9−) within the porous channels of an ethylene-bridged TMAPS-functionalized BPMO produced a luminescent material exhibiting a strong red emission under UV irradiation. Photoluminescence studies showed an efficient energy transfer process to the lanthanide emitting center in the material (antenna effect). A significant change in the coordination environment of Eu3+ ions was observed after its incorporation into the TMAPS-functionalized material. The possible reason for this is discussed within the paper.

Carepo, MS, Carreira C, Grazina R, Zakrzewska ME, Dolla A, Aubert C, Pauleta SR, Moura JJG, Moura I.  2016.  Orange protein from Desulfovibrio alaskensis G20: insights into the Mo-Cu cluster protein-assisted synthesis. J Biol Inorg Chem. 21:53-62.
Machado, C, Machado A, Alves LC, Vilarigues M.  2016.  The past and the present: Commercial grisailles from Debitus. Proceedings of the 5th International Conference Youth in Conservation of Cultural Heritage – YOCOCU. , Madrid
Ruivo, A, Andrade S, Ferro M, Rocha J, Laia C, Pina F.  2016.  Photoluminescent Nanocrystals in a Multicomponent Aluminoborosilicate Glass. Journal of Physical Chemistry C. 120:24925−24931.
Almeida, RM, Dell'Acqua S, Krippahl L, Moura JJG, Pauleta SR.  2016.  Predicting Protein-Protein Interactions Using BiGGER: Case Studies. Molecules. 21:1037.Website
Craveiro, R, Aroso I, Flammia V, Carvalho T, Viciosa MT, Dionísio M, Barreiros S, Reis RL, Duarte ARC, Paiva A.  2016.  Properties and thermal behavior of natural deep eutectic solvents. Journal of Molecular Liquids. 215:534-540.Website
Carvalho, R, Almeida R, Moura JJG, Lourenço N, Fonseca L, Cordas CM.  2016.  Sandwich-Type Enzymatic Fuel Cell Based on a New Electro-Conductive Material - Ion Jelly. Chemistry Select. 1:6546–6552.Website
João, C, Almeida R, Silva JC, Borges JP.  2016.  A simple sol-gel route to the construction of hydroxyapatite inverted colloidal crystals for bone tissue engineering. Materials Letters. 185:407-410. AbstractWebsite

Hydroxyapatite (HAp) scaffolds with uniform pore size and interconnected pore network were constructed based on the inverted colloidal crystal (ICC) geometry and a simple sol-gel formulation. Monodisperse polystyrene microspheres were self-assembled and annealed into a hexagonal close packed structure. HAp sol-gel was infiltrated in this template followed by thermal treatment for simultaneous HAp matrix sintering and polymeric colloidal crystal calcination. The resultant ICC scaffolds exhibit an ordered architecture that was able to offer a favorable environment for human osteoblasts adhesion and proliferation, an essential feature for bone ingrowth in tissue engineering applications.

Santos, L, Silveira CM, Elangovan E, Neto JP, Nunes D, Pereira L, Martins R, Viegas J, Moura JJG, Todorovic S, Almeida MG, Fortunato EM.  2016.  Synthesis of WO3 nanoparticles for biosensing applications. Sensors and Actuators B: Chemical. 223:186-194.
Jesus, T F, Grosso AR, Almeida-Val VMF, Coelho MM.  2016.  Transcriptome profiling of two Iberian freshwater fish exposed to thermal stress. Journal of Thermal Biology. 55:54–61.: Elsevier AbstractWebsite

The congeneric freshwater fish Squalius carolitertii and S. torgalensis inhabit different Iberian regions with distinct climates; Atlantic in the North and Mediterranean in the South, respectively. While northern regions present mild temperatures, fish in southern regions often experience harsh temperatures and droughts. Previous work with two hsp70 genes suggested that S. torgalensis is better adapted to harsher thermal conditions than S. carolitertii as a result of the different environmental conditions. We present a transcriptomic characterisation of these species' thermal stress responses. Through differential gene expression analysis of the recently available transcriptomes of these two endemic fish species, comprising 12 RNA-seq libraries from three tissues (skeletal muscle, liver and fins) of fish exposed to control (18 °C) and test (30 °C) conditions, we intend to lay the foundations for further studies on the effects of temperature given predicted climate changes. Results showed that S. carolitertii had more upregulated genes, many of which are involved in transcription regulation, whereas S. torgalensis had more downregulated genes, particularly those responsible for cell division and growth. However, both species displayed increased gene expression of many hsps genes, suggesting that they are able to deal with protein damage caused by heat, though with a greater response in S. torgalensis. Together, our results suggest that S. torgalensis may have an energy saving strategy during short periods of high temperatures, re-allocating resources from growth to stress response mechanisms. In contrast, S. carolitertii regulates its metabolism by increasing the expression of genes involved in transcription and promoting the stress response, probably to maintain homoeostasis. Additionally, we indicate a set of potential target genes for further studies that may be particularly suited to monitoring the responses of Cyprinidae to changing temperatures, particularly for species living in similar conditions in the Mediterranean Peninsulas.

Alves, MN, Fernandes AP, Salgueiro CA, Paquete CM.  2016.  Unraveling the electron transfer processes of a nanowire protein from Geobacter sulfurreducens. BBA - Bioenergetics. 1857(1):7-13. AbstractWebsite

The extracellular electron transfer metabolism of Geobacter sulfurreducens is sustained by several multiheme c-type cytochromes. One of these is the dodecaheme cytochrome GSU1996 that belongs to a new sub-class of c-type cytochromes. GSU1996 is composed by four similar triheme domains (A-D). The C-terminal half of the molecule encompasses the domains C and D, which are connected by a small linker and the N-terminal half of the protein contains two domains (A and B) that form one structural unit. It was proposed that this protein works as an electrically conductive device in Geobacter sulfurreducens, transferring electrons within the periplasm or to outer-membrane cytochromes. In this work, a novel strategy was applied to characterize in detail the thermodynamic and kinetic properties of the hexaheme fragment CD of GSU1996. This characterization revealed the electron transfer process of GSU1996 for the first time, showing that a heme at the edge of the C-terminal of the protein is thermodynamic and kinetically competent to receive electrons from physiological redox partners. This information contributes towards understanding how this new sub-class of cytochromes functions as nanowires, and also increases the current knowledge of the extracellular electron transfer mechanisms in Geobacter sulfurreducens.

Sharipova, AA, Aidarova SB, Bekturganova NE, Tleuova A, Schenderlein M, Lygina O, Lyubchik S, Miller R.  2016.  Triclosan as model system for the adsorption on recycled adsorbent materials. Colloids and Surfaces A: Physicochemical and Engineering Aspects. 505:193-196. AbstractWebsite

The adsorption of triclosan as model system was studied to qualify activated carbon sorbents recycled from gas masks (civilian gas mask GP5). The triclosan equilibrium concentration was measured spectrophotometrically, the morphology of the activated carbon characterized by scanning electron microscopy, and the amount of the adsorbed triclosan on the activated carbon quantified by a mass balance method. Experimental isotherms were fitted by Langmuir, Freundlich and Sips adsorption models. It was obtained that the contact time is a crucial sorption parameter that provides information on the optimum adsorption efficiency. It was shown that the maximum efficiency of GP5 (88%) is obtained after 10days of adsorption at a maximal concentration of triclosan and carbon loading 1mg/l. No significant adsorption efficiency differences were measured after 5 and 10days of adsorption. The non-linear Sips isotherm, a combined Freundlich–Langmuir model, provides suitable fitting results. The observed remarkable adsorption capacity of activated carbon (GP5) towards triclosan adsorption (∼85mg/g) makes it a viable solution for wastewater treatment.

2015
Sena, FV, Batista AP, Catarino T, Brito JA, Archer M, Viertler M, Madl T, Cabrita EJ, Pereira MM.  2015.  Type-II NADH:quinone oxidoreductase from Staphylococcus aureus has two distinct binding sites and is rate limited by quinone reduction, {OCT}. Molecular Microbiology. 98:272-288., Number {2} Abstract

A prerequisite for any rational drug design strategy is understanding the mode of protein-ligand interaction. This motivated us to explore protein-substrate interaction in Type-II NADH:quinone oxidoreductase (NDH-2) from Staphylococcus aureus, a worldwide problem in clinical medicine due to its multiple drug resistant forms. NDHs-2 are involved in respiratory chains and recognized as suitable targets for novel antimicrobial therapies, as these are the only enzymes with NADH:quinone oxidoreductase activity expressed in many pathogenic organisms. We obtained crystal and solution structures of NDH-2 from S. aureus, showing that it is a dimer in solution. We report fast kinetic analyses of the protein and detected a charge-transfer complex formed between NAD(+) and the reduced flavin, which is dissociated by the quinone. We observed that the quinone reduction is the rate limiting step and also the only half-reaction affected by the presence of HQNO, an inhibitor. We analyzed protein-substrate interactions by fluorescence and STD-NMR spectroscopies, which indicate that NADH and the quinone bind to different sites. In summary, our combined results show the presence of distinct binding sites for the two substrates, identified quinone reduction as the rate limiting step and indicate the establishment of a NAD(+)-protein complex, which is released by the quinone.

Coelho, H, Matsushita T, Artigas G, Hinou H, Javier Canada F, Lo-Man R, Leclerc C, Cabrita EJ, Jimenez-Barbero J, Nishimura S-I, Garcia-Martin F, Marcelo F.  2015.  The Quest for Anticancer Vaccines: Deciphering the Fine-Epitope Specificity of Cancer-Related Monoclonal Antibodies by Combining Microarray Screening and Saturation Transfer Difference NMR, {OCT 7}. Journal of the American Chemical Society. 137:12438-12441., Number {39} Abstract

The identification of MUC1 tumor-associated Tn antigen (alpha GalpNAc1-O-Ser/Thr) has boosted the development of anticancer vaccines. Combining microarrays and saturation transfer difference NMR, we have characterized the fine-epitope mapping of a MUC1 chemical library (naked and Tn-glycosylated) toward two families of cancer-related monoclonal antibodies (anti-MUC1 and anti-Tn mAbs). Anti-MUC1 mAbs clone VU-3C6 and VU-11E2 recognize naked MUC1-derived peptides and bind GalNAc in a peptide-sequence-dependent manner. In contrast, anti-Tn mAbs clone 8D4 and 14D6 mostly recognize the GalNAc and do not bind naked MUC1-derived peptides. These anti-Tn mAbs show a clear preference for glycopeptides containing the Tn-Ser antigen rather than the Tn-Thr analogue, stressing the role of the underlying amino acid (serine or threonine) in the binding process. The reported strategy can be employed, in general, to unveil the key minimal structural features that modulate antigen-antibody recognition, with particular relevance for the development of Tn-MUC1-based anticancer vaccines.

Araújo, N.  2015.  A reindustrialização de Portugal num contexto de crise e hegemonia industrial dos países emergentes, WPS03/2015. :20., Monte de Caparica: IET Working Papers Series Abstract

This working paper aimed to understand the importance and the role of Industry for the Portuguese' economic recovery, integrated in a context of progressive deindustrialisation over the last few years, and simultaneously an impressive growth and domain over some production sectors by emergent countries, associated with the 2008 crisis. We intended to analyse this problematic in both national and European levels, bringing into context the national industry, identifying the causes for the progressive abandon of the industry and its consequences. To identify the main stakeholders and their role on the reindustrialization process. To identify policies and instruments contributing to the promotion of this reindustrialisation and main conclusions.

Andrade, MS, Silva VS, Lourenco AM, Lobo AM, Rzepa HS.  2015.  Chiroptical Properties of Streptorubin B: The Synergy Between Theory and Experiment, OCT. CHIRALITY. 27:745-751., Number 10 Abstract
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Bernacka-Wojcik, I, Águas H, Carlos {FF}, Lopes P, Wojcik {PJ}, Costa {MN}, Veigas B, Igreja R, Fortunato E, Baptista P, Martins R.  2015.  Single Nucleotide Polymorphism Detection Using Gold Nanoprobes and Bio-Microfluidic Platform With Embedded Microlenses, jun. Biotechnology and Bioengineering. 112:1210–1219., Number 6: Wiley-Blackwell Abstract

The use of microfluidics platforms combined with the optimal optical properties of gold nanopartides has found plenty of application in molecular biosensing. This paper describes a biotnicrofluidic platform coupled to a non-cross-linking colorimetric gold nanoprobe assay to detect a single nucleotide polymorphism associated with increased risk of obesity fat-mass and obesity-associated (FTO) rs9939609 (Carlos et al., 2014). The system enabled significant discrimination between positive and negative assays using a target DNA concentration of 5 ng/mu l below the limit of detection of the conventionally used microplate reader (i.e., 15 ng/mu l) with 10 times lower solution volume (i.e., 3 mu l.). A set of optimization of our previously reported bio-microfluidic platform (Bemacka-Wojcik et al., 2013) resulted in a 160% improvement of colorimetric analysis results. Incorporation of planar microlenses increased 6 times signal-to-loss ratio reaching the output optical fiber improving by 34% the colorimetric analysis of gold nanopartides, while the implementation of an optoelectronic acquisition system yielded increased accuracy and reduced noise. The microfluidic chip was also integrated with a miniature fiber spectrometer to analyze the assays' cobrimetric changes and also the LEDs transmission spectra when illuminating through various solutions. Furthermore, by coupling an optical micmscope to a digital camera with a long exposure time (30s), we could visualise the different scatter intensities of gold nanoparticles within channels following salt addition. These intensities correlate well to the expected difference in aggregation between FTO positive (none to small aggregates) and negative samples (large aggregates). (C) 2015 Wiley Periodicals, Inc.

Bernacka-Wojcik, I, Aguas H, Carlos FF, Lopes P, Wojcik PJ, Costa MN, Veigas B, Igreja R, Fortunato E, Baptista PV, Martins R.  2015.  {Single Nucleotide Polymorphism Detection Using Gold Nanoprobes and Bio-Microfluidic Platform With Embedded Micro lenses}, jun. BIOTECHNOLOGY AND BIOENGINEERING. 112:1210–1219., Number 6 Abstract
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Aguas, H, Mateus T, Vicente A, Gaspar D, Mendes MJ, Schmidt WA, Pereira L, Fortunato E, Martins R.  2015.  {Thin Film Silicon Photovoltaic Cells on Paper for Flexible Indoor Applications}, jun. ADVANCED FUNCTIONAL MATERIALS. 25:3592–3598., Number 23 Abstract
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Pavan, M, Rühle S, Ginsburg A, Keller DA, Barad H-N, Sberna PM, Nunes D, Martins R, Anderson AY, Zaban A, Fortunato E.  2015.  {TiO2/Cu2O all-oxide heterojunction solar cells produced by spray pyrolysis}, jan. Solar Energy Materials and Solar Cells. 132:549–556. AbstractWebsite

Here we present for the first time a TiO2/Cu2O all-oxide heterojunction solar cell entirely produced by spray pyrolysis onto fluorine doped tin oxide (FTO) covered glass substrates, using silver as a back contact. A combinatorial approach was chosen to investigate the impact of the TiO2 window layer and the Cu2O light absorber thicknesses. We observe an open circuit voltage up to 350mV and a short circuit current density which is strongly dependent of the Cu2O thickness, reaching a maximum of {\~{}}0.4mA/cm2. Optical investigation reveals that a thickness of 300nm spray pyrolysis deposited Cu2O is sufficient to absorb most photons with an energy above the symmetry allowed optical transition of 2.5eV, indicating that the low current densities are caused by strong recombination in the absorber that consists of small Cu2O grains.

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