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2016
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
João, CFC, Baptista AC, Ferreira IMM, Silva JC, Borges JP.  2016.  https://vtt.pure.elsevier.com/en/publications/transflexteg-large-area-transparent-thin-film-thermoelectric-devi. Fibrous and textile materials for composite applications. :261-299., Singapore: Springer Abstract

Cellulose and chitin are the two most abundant natural polysaccharides. Both have a semicrystalline microfibrillar structure from which nanofibres can be extracted. These nanofibres are rod-like microcrystals that can be used as nanoscale reinforcements in composites due to their outstanding mechanical properties. This chapter starts by reviewing the sources, extraction methods and properties of cellulose and chitin nanofibres. Then, their use in the fabrication of structural and functional nanocomposites and the applications that have been investigated are reviewed. Nanocomposites are materials with internal nano-sized structures. They benefit from the properties of the nanofillers: low density, nonabrasive, nontoxic, low cost, susceptibility to chemical modifications and biodegradability. Diverse manufacturing technologies have been used to produce films, fibres, foams, sponges, aerogels, etc. Given their natural origin and high stiffness, these polymers have attracted a lot of attention not only in the biomedical and tissue engineering fields but also in areas such as pharmaceutics, cosmetics, agriculture, biosensors and water treatment.

Thiel, C, Nijs W, Simões S, Schmidt J, van Zyl A, Schmid E.  2016.  The impact of the EU car CO2 regulation on the energy system and the role of electro-mobility to achieve transport decarbonisation. Energy Policy Journal. 96:153-166.
Soares, PIP, Laia C, Carvalho A, Pereira L, Coutinho J, Ferreira I, Novo C, Borges JP.  2016.  Iron oxide nanoparticles stabilized with a bilayer of oleic acid for magnetic hyperthermia and MRI applications. Applied Surface Science. 383:240-247. AbstractWebsite

Iron oxide nanoparticles (Fe3O4, IONPs) are promising candidates for several biomedical applications such as magnetic hyperthermia and as contrast agents for magnetic resonance imaging (MRI). However, their colloidal stability in physiological conditions hinders their application requiring the use of biocompatible surfactant agents. The present investigation focuses on obtaining highly stable IONPs, stabilized by the presence of an oleic acid bilayer. Critical aspects such as oleic acid concentration and pH were optimized to ensure maximum stability. NPs composed of an iron oxide core with an average diameter of 9 nm measured using transmission electron microscopy (TEM) form agglomerates with an hydrodynamic diameter of around 170 nm when dispersed in water in the presence of an oleic acid bilayer, remaining stable (zeta potential of −120 mV). Magnetic hyperthermia and the relaxivities measurements show high efficiency at neutral pH which enables their use for both magnetic hyperthermia and MRI.

Soares, PIP, Laia CAT, Carvalho A, Pereira LCJ, Coutinho JT, Ferreira IMM, Novo CMM, Borges JP.  2016.  Iron oxide nanoparticles stabilized with a bilayer of oleic acid for magnetic hyperthermia and MRI applications. Appl Surf Sci. 383:240-247. AbstractWebsite

Iron oxide nanoparticles (Fe3O4, IONPs) are promising candidates for several biomedical applications such as magnetic hyperthermia and as contrast agents for magnetic resonance imaging (MRI). However, their colloidal stability in physiological conditions hinders their application requiring the use of biocompatible surfactant agents. The present investigation focuses on obtaining highly stable IONPs, stabilized by the presence of an oleic acid bilayer. Critical aspects such as oleic acid concentration and pH were optimized to ensure maximum stability. NPs composed of an iron oxide core with an average diameter of 9 nm measured using transmission electron microscopy (TEM) form agglomerates with an hydrodynamic diameter of around 170 nm when dispersed in water in the presence of an oleic acid bilayer, remaining stable (zeta potential of −120 mV). Magnetic hyperthermia and the relaxivities measurements show high efficiency at neutral pH which enables their use for both magnetic hyperthermia and MRI.

Santos, T, Carvalho J, Corvo MC, Cabrita EJ, Queiroz JA, Cruz C.  2016.  L-tryptophan and dipeptide derivatives for supercoiled plasmid DNA purification. International Journal of Biological Macromolecules. 87:385-396.: Elsevier AbstractWebsite

The present study focus on the preparation of chromatography supports for affinity-based chromatography of supercoiled plasmid purification. Three l-tryptophan based supports are prepared through immobilization on epoxy-activated Sepharose and characterized by HR-MAS NMR. The SPR is employed for a fast screening of l-tryptophan derivatives, as potential ligands for the biorecognition of supercoiled isoform, as well as, to establish the suitable experimental conditions for the chromatography. The results reveal that the overall affinity is high (KD = 10−9 and 10−8 M) and the conditions tested show that the use of HEPES 100 mM enables the separation and purification of supercoiled at T = 10 °C. The STD-NMR is performed to accomplish the epitope mapping of the 5′-mononucleotides bound to l-tryptophan derivatives supports. The data shows that the interactions between the three supports and the 5′-mononucleotides are mainly hydrophobic and π–π stacking. The chromatography experiments are performed with l-tryptophan support and plasmids pVAX-LacZ and pPH600. The supercoiled isoform separation is achieved at T = 10 °C by decreasing the concentration of (NH4)2SO4 from 2.7 to 0 M in HEPES for pVAX-LacZ and 2.65 M to 0 M in HEPES for pPH600.

Overall, l-tryptophan derivatives can be a promising strategy to purify supercoiled for pharmaceutical applications.

Simoes, SG, Gregório V, Seixas J.  2016.  Mapping fuel poverty in Portugal. Energy Procedia. 106:155–165.
Batista, AG, Najdi S, Godinho DM, Serrano F, Ortigueira MD, Rato RT.  2016.  A Multichannel Time-Frequency and Multi-Wavelet Toolbox for Uterine Electromyography Processing and Visualisation. Computers in Biology and Medicine.. 76.1:178-191.
Salgueiro, CA, Dantas JM.  2016.  Multiheme Cytochromes. Multiheme Cytochromes. :1–39., Berlin, Heidelberg: Springer Berlin Heidelberg Abstract

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João, C, Baptista AC, Ferreira I, Silva JC, Borges JP.  2016.  Natural Nanofibres for Composite Applications. Fibrous and Textile Materials for Composite Applications. (Sohel Rana, Raul Fangueiro, Eds.).:261-299., Singapore: Springer Singapore Abstract

Cellulose and chitin are the two most abundant natural polysaccharides. Both have a semicrystalline microfibrillar structure from which nanofibres can be extracted. These nanofibres are rod-like microcrystals that can be used as nanoscale reinforcements in composites due to their outstanding mechanical properties. This chapter starts by reviewing the sources, extraction methods and properties of cellulose and chitin nanofibres. Then, their use in the fabrication of structural and functional nanocomposites and the applications that have been investigated are reviewed. Nanocomposites are materials with internal nano-sized structures. They benefit from the properties of the nanofillers: low density, nonabrasive, nontoxic, low cost, susceptibility to chemical modifications and biodegradability. Diverse manufacturing technologies have been used to produce films, fibres, foams, sponges, aerogels, etc. Given their natural origin and high stiffness, these polymers have attracted a lot of attention not only in the biomedical and tissue engineering fields but also in areas such as pharmaceutics, cosmetics, agriculture, biosensors and water treatment.

Fundo, JF, Galvis-Sanchez A, Madureira AR, Carvalho A, Feio G, Silva CLM, Quintas MAC.  2016.  NMR water transverse relaxation time approach to understand storage stability of fresh-cut ‘Rocha’pear. LWT-Food Science and Technology. 74:280-285. AbstractWebsite

Fresh-cut fruit is an important segment in fruit market due to the increasing demand for healthy/convenient foods. However, processing promotes a decrease in fruits stability with faster physiological and microbiological deteriorations. Food stability is strongly attributed to its molecular dynamics and “water availability”. Understanding changes in water location/mobility is of utmost importance, since water dynamics profoundly influences physic-chemical and microbiological quality of foods. Nuclear magnetic resonance spectroscopy (NMR) is a methodology used to study the food constituents' molecular dynamics.

The aim of this study is to use NMR to evaluate changes in water mobility that occurred in fresh-cut pear tissues during storage, by measuring the transverse relaxation time (T2) parameter.

Results showed the existence of three water classes in the cells after processing, with T2 values of 10 ms, 187 ms and 3s for cellular wall, cytoplasm and vacuole, respectively. Also, the obtained results demonstrated that T2 was affected by processing and storage. Moreover, a relationship between T2, microstructure and the quality parameters was established. T2, maximum value increased with pear hardness as well as water activity. On the contrary, a decrease in total colour difference (TCD) was found with T2.

Results demonstrate the usefulness of the application of NMR relaxometry in food studies.

Yang, Y, Wikieł AJ, Dall'agnol LT, Eloy P, Genet MJ, Moura JJG, Sand W, Dupont-Gillain CC, Rouxhet PG.  2016.  Proteins dominate in the surface layers formed on materials exposed to extracellular polymeric substances from bacterial cultures. Biofouling. 32:95-108.
Krings, B-J, Rodriguez H, Schleisiek A.  2016.  Scientific knowledge and the transgression of boundaries. , Wiesbaden: Springer VS Abstract

The aim of this book is to understand and critically appraise science-based transgression dynamics in their whole complexity. It includes contributions from experts with different disciplinary backgrounds, such as philosophy, history and sociology. Thus, it is in itself an example of boundary transgession. Scientific disciplines and their objects have tended to be seen as permanent and distinct. However, science is better conceived as an activity that constantly surpasses, erases and rebuilds all kinds of boundaries, either disciplinary, socio-ethical or ecological. This transgressive capacity, a characteristic trait of science and its applications, defines us as "knowledge societies." However, scientific and technological developments are also sources of serious environmental and social concerns.

Silva, M, Silva Z, Marques G, Ferro T, Gonçalves M, Monteiro M, van Vliet SJ, Mohr E, Lino AC, Fernandes AR, Lima FA, van Kooyk Y, Matos T, Tadokoro CE, Videira PA.  2016.  Sialic acid removal from dendritic cells improves antigen cross-presentation and boosts anti-tumor immune responses. Oncotarget . AbstractWebsite

Dendritic cells (DCs) hold promise for anti-cancer immunotherapy. However, clinically, their efficiency is limited and novel strategies to improve DC-mediated anti-tumor responses are needed. Human DCs display high content of sialic acids, which inhibits their maturation and co-stimulation capacity. Here, we aimed to understand whether exogenous desialylation of DCs improves their anti-tumor immunity. Compared to fully sialylated DCs, desialylated human DCs loaded with tumor-antigens showed enhanced ability to induce autologous T cells to proliferate, to secrete Th1 cytokines, and to specifically induce tumor cell apoptosis. Desialylated DCs showed an increased expression of MHC-I and -II, co-stimulatory molecules and an augmented secretion of IL-12. Desialylated HLA-A*02:01 DCs pulsed with gp100 peptides displayed enhanced peptide presentation through MHC-I, resulting in higher activation ofgp100280–288 specific CD8+ cytotoxic T cells. Desialylated murine DCs also exhibited increased MHC and co-stimulatory molecules and higher antigen cross-presentation via MHC-I. These DCs showed higher ability to activate antigen-specific CD4+ and CD8+ T cells, and to specifically induce tumor cell apoptosis. Collectively, our data demonstrates that desialylation improves DCs’ ability to elicit T cell-mediated anti-tumor activity, due to increased MHC-I expression and higher antigen presentation via MHC-I. Sialidase treatment of DCs may represent a technology to improve the efficacy of antigen loaded-DC-based vaccines for anti-cancer immunotherapy.

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.
Ma, Z, Zhang B, da Silva FGMC, Mendo AS, Silva J, Baptista PV, Fernandes AR, Pombeiro AJL.  2016.  Synthesis, Characterization, Thermal Properties and Antiproliferative Potential of Copper(II) 4′-phenyl-terpyridine Compounds. Dalton Transations. (12) AbstractWebsite

Reactions between 4′-phenyl-terpyridine (L) and several Cu(II) salts (p-toluenesulfonate, benzoate and o-, m- or p-hydroxybenzoate) led to the formation of [Cu(p-SO3C6H4CH3)L(H2O)2](p-SO3C6H4CH3) (1), [Cu(OCOPh)2L] (2), [Cu(o-OCOC6H4OH)2L] (3), [Cu(m-OCOC6H4OH)2L]·MeOH (4·MeOH) and [Cu(p-OCOC6H4OH)2L]·2H2O (5·2H2O), which were characterized by elemental and TG-DTA analyses, ESI-MS, IR spectroscopy and single crystal X-ray diffraction, as well as by conductivimetry. In all structures the Cu atoms present N3O3 octahedral coordination geometries, which, in 2–5, are highly distorted as a result of the chelating-bidentate mode of one of the carboxylate ligands. Intermolecular π⋯π stacking interactions could also be found in 2–5 (in the 3.569–3.651 Å range and involving solely the pyridyl rings). Medium–strong hydrogen bond interactions lead to infinite 1D chains (in 1 and 4) and to an infinite 2D network (in 5). Compounds 1 and 4 show high in vitro cytotoxicity towards HCT116 colorectal carcinoma and HepG2 hepatocellular carcinoma cell lines. The antiproliferative potential of compound 1 is due to an increase of the apoptotic process that was confirmed by Hoechst staining, flow cytometry and RT-qPCR. All compounds able to non-covalently intercalate the DNA helix and induce in vitro pDNA double-strand breaks in the absence of H2O2. Concerning compound 1, the hydroxyl radical and singlet oxygen do not appear to be involved in the pDNA cleavage process and the fact that this cleavage also occurs in the absence of molecular oxygen points to a hydrolytic mechanism of cleavage.

Muñoz-ruiz, M, Ribot JC, Grosso AR, Gonçalves-sousa N, Pamplona A, Pennington DJ, Regueiro JR, Fernández-malavé E, Silva-santos B.  2016.  TCR signal strength controls thymic differentiation of discrete proinflammatory γδT cell subsets. Nature immunology. , Number April AbstractWebsite

The mouse thymus produces discrete γδ T cell subsets that make either interferon-γ (IFN-γ) or interleukin 17 (IL-17), but the role of the T cell antigen receptor (TCR) in this developmental process remains controversial. Here we show that Cd3g(+/-) Cd3d(+/-) (CD3 double-haploinsufficient (CD3DH)) mice have reduced TCR expression and signaling strength on γδ T cells. CD3DH mice had normal numbers and phenotypes of αβ thymocyte subsets, but impaired differentiation of fetal Vγ6(+) (but not Vγ4(+)) IL-17-producing γδ T cells and a marked depletion of IFN-γ-producing CD122(+) NK1.1(+) γδ T cells throughout ontogeny. Adult CD3DH mice showed reduced peripheral IFN-γ(+) γδ T cells and were resistant to experimental cerebral malaria. Thus, TCR signal strength within specific thymic developmental windows is a major determinant of the generation of proinflammatory γδ T cell subsets and their impact on pathophysiology.

Soares, PIP, Machado D, Laia C, Pereira L, Coutinho J, Ferreira I, Novo C, Borges JP.  2016.  Thermal and magnetic properties of chitosan-iron oxide nanoparticles. Carbohydrate polymers. 149:382-390. AbstractWebsite

Chitosan is a biopolymer widely used for biomedical applications such as drug delivery systems, wound healing, and tissue engineering. Chitosan can be used as coating for other types of materials such as iron oxide nanoparticles, improving its biocompatibility while extending its range of applications.
In this work iron oxide nanoparticles (Fe3O4 NPs) produced by chemical precipitation and thermal decomposition and coated with chitosan with different molecular weights were studied. Basic characterization on bare and chitosan-Fe3O4 NPs was performed demonstrating that chitosan does not affect the crystallinity, chemical composition, and superparamagnetic properties of the Fe3O4 NPs, and also the incorporation of Fe3O4 NPs into chitosan nanoparticles increases the later hydrodynamic diameter without compromising its physical and chemical properties. The nano-composite was tested for magnetic hyperthermia by applying an alternating current magnetic field to the samples demonstrating that the heating ability of the Fe3O4 NPs was not significantly affected by chitosan.

Soares, PIP, Machado D, Laia C, Pereira LCJ, Coutinho JT, Ferreira IMM, Novo CMM, Borges JP.  2016.  Thermal and magnetic properties of chitosan-iron oxide nanoparticles. Carbohydr Polym. 149:382-390. AbstractWebsite

Chitosan is a biopolymer widely used for biomedical applications such as drug delivery systems, wound healing, and tissue engineering. Chitosan can be used as coating for other types of materials such as iron oxide nanoparticles, improving its biocompatibility while extending its range of applications.

In this work iron oxide nanoparticles (Fe3O4 NPs) produced by chemical precipitation and thermal decomposition and coated with chitosan with different molecular weights were studied. Basic characterization on bare and chitosan-Fe3O4 NPs was performed demonstrating that chitosan does not affect the crystallinity, chemical composition, and superparamagnetic properties of the Fe3O4 NPs, and also the incorporation of Fe3O4 NPs into chitosan nanoparticles increases the later hydrodynamic diameter without compromising its physical and chemical properties. The nano-composite was tested for magnetic hyperthermia by applying an alternating current magnetic field to the samples demonstrating that the heating ability of the Fe3O4 NPs was not significantly affected by chitosan.

Soares, PIP, Sousa AI, Ferreira I, Novo C, Borges JB.  2016.  Towards the development of multifunctional chitosan-based iron oxide nanoparticles: Optimization and modelling of doxorubicin release. Carbohydrate Polymers. 153:212-221. AbstractWebsite

In the present work composite nanoparticles with a magnetic core and a chitosan-based shell were produced as drug delivery systems for doxorubicin (DOX). The results show that composite nanoparticles with a hydrodynamic diameter within the nanometric range are able to encapsulate more DOX than polymeric nanoparticles alone corresponding also to a higher drug release. Moreover the synthesis method of the iron oxide nanoparticles influences the total amount of DOX released and a high content of iron oxide nanoparticles inhibits DOX release. The modelling of the experimental results revealed a release mechanism dominated by Fickian diffusion.

Soares, PIP, Sousa AI, Ferreira IMM, Novo CMM, Borges JP.  2016.  Towards the development of multifunctional chitosan-based iron oxide nanoparticles: Optimization and modelling of doxorubicin release. Carbohydr Polym. 153:212-221. AbstractWebsite

In the present work composite nanoparticles with a magnetic core and a chitosan-based shell were produced as drug delivery systems for doxorubicin (DOX). The results show that composite nanoparticles with a hydrodynamic diameter within the nanometric range are able to encapsulate more DOX than polymeric nanoparticles alone corresponding also to a higher drug release. Moreover the synthesis method of the iron oxide nanoparticles influences the total amount of DOX released and a high content of iron oxide nanoparticles inhibits DOX release. The modelling of the experimental results revealed a release mechanism dominated by Fickian diffusion.

Gouveia, JP, Seixas J.  2016.  Unraveling electricity consumption profiles in households through clusters: Combining smart meters and door-to-door surveys. Energy and Buildings. 116:666–676. AbstractWebsite

Improvements of energy efficiency and reduction of Electricity Consumption (EC) could be pushed by increased knowledge on consumption profiles. This paper contributes to a comprehensive understanding of the EC profiles in a Southwest European city through the combination of high-resolution data from smart meters (daily electricity consumption) with door-to-door 110-question surveys for a sample of 265 households in the city of Évora, in Portugal. This analysis allowed to define ten power consumption clusters using Ward's method hierarchical clustering, corresponding to four distinct types of annual consumption profiles: U shape (sharp and soft), W shape and Flat. U shape pattern is the most common one, covering 77% of the sampled households.
The results show that three major groups of determinants characterize the electricity consumption segmentation: physical characteristics of a dwelling, especially year of construction and floor area; HVAC equipment and fireplaces ownership and use; and occupants’ profiles (mainly number and monthly income).
The combination of the daily EC data with qualitative door-to-door survey-based data proved to be a powerful data nutshell to distinguish groups of power consumers, allowing to derive insights to support DSOs, ESCOs, and retailers to design measures and instruments targeted to effective energy reduction (e.g. peak shaving, energy efficiency).

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.