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2018
Lenis-Rojas, OA, Robalo MP, Tomaz AI, Carvalho A, Fernandes AR, Marques F, Folgueira M, Yanez J, Vazquez-Garcia D, Lopez Torres M, Fernandez A, Fernandez JJ.  2018.  Ru(II)( p-cymene) Compounds as Effective and Selective Anticancer Candidates with No Toxicity in Vivo, 2018. Inorg Chem. 57(21):13150-13166. AbstractWebsite

Ruthenium(II) complexes are currently considered a viable alternative to the widely used platinum complexes as efficient anticancer agents. We herein present the synthesis and characterization of half-sandwich ruthenium compounds with the general formula [Ru( p-cymene)(L-N,N)Cl][CF3SO3] (L = 3,6-di-2-pyridyl-1,2,4,5-tetrazine (1) 6,7-dimethyl-2,3-bis(pyridin-2-yl)quinoxaline (2)), which have been synthesized by substitution reactions from the precursor dimer [Ru( p-cymene)(Cl)(mu-Cl)]2 and were characterized by elemental analysis, mass spectrometry, (1)H NMR, UV-vis, and IR spectroscopy, conductivity measurements, and cyclic voltammetry. The molecular structure for complex 2 was determined by single-crystal X-ray diffraction. The cytotoxic activity of these compounds was evaluated against human tumor cells, namely ovarian carcinoma A2780 and breast MCF7 and MDAMB231 adenocarcinoma cells, and against normal primary fibroblasts. Whereas the cytotoxic activity of 1 is moderate, IC50 values found for 2 are among the lowest previously reported for Ru( p-cymene) complexes. Both compounds present no cytotoxic effect in normal human primary fibroblasts when they are used at the IC50 concentration in A2780 and MCF7 cancer cells. Their antiproliferative capacity is associated with a combined mechanism of apoptosis and autophagy. A strong interaction with DNA was observed for both with a binding constant value of the same magnitude as that of the classical intercalator [Ru(phen)2(dppz)](2+). Both complexes bind to human serum albumin with moderate to strong affinity, with conditional binding constants (log Kb) of 4.88 for complex 2 and 5.18 for complex 1 in 2% DMSO/10 mM Hepes pH7.0 medium. The acute toxicity was evaluated in zebrafish embryo model using the fish embryo acute toxicity test (FET). Remarkably, our results show that compounds 1 and 2 are not toxic/lethal even at extremely high concentrations. The novel compounds reported herein are highly relevant antitumor metallodrug candidates, given their in vitro cytotoxicity toward cancer cells and the lack of in vivo toxicity.

Dias, D, Bernardo M, Lapa N, Pinto F, Matos I, Fonseca I.  2018.  Activated carbons from the Co-pyrolysis of rice wastes for Cr(III) removal. Chemical Engineering Transactions. 65:601-606.
Lopes, R, Magalhães P, Gouveia JP, Aelenei D, Lima C, Martins J.  2018.  A case study on the impact of nearly Zero-Energy Buildings on distribution transformer aging. Energy. 157:669-678.
Giannakidis, G, Gargiulo M, De Miglio R, Chiodi A, Seixas J, Simoes SG, Dias L, Gouveia J.  2018.  Challenges faced when addressing the role of cities towards a below 2-degree world. Limiting Global Warming to Well Below 2°C: Energy System Modelling and Policy Development. (Giannakidis G., K. Karlsson, M. Labriet, B. Ó Gallachóir, Eds.).: Lecture Notes in Energy 64. Springer International publishing. Doi: 10.1007/978-3-319-74424-7
Surra, E, Bernardo M, Lapa N, Esteves IAAC, Fonseca I, Mota JP.  2018.  Enhanced Biogas Production through Anaerobic co-Digestion of OFMSW with Maize Cob Waste Pre-Treated with Hydrogen Peroxide. Chemical Engineering Transactions. 65:121-126.
Sousa, DM, Cerqueira L, Marques A, Gaspar G, Lima JC, Ferreira I.  2018.  Facile Microwave-assisted Synthesis Manganese Doped Zinc Sulfide Nanoparticles. Scientific Reports. 8:15992.
Reckien, D, Heidrich O, Church J, Pietrapertos F, De Gregorio-Hurtado S, D'Alonzo V, Foley A, Simoes SG, Lorencová EK, Orruk H, Orrum K, Wejs A, Flacke J, Olazabal M, Geneletti D, Feliu E, Vasilier S, Nador C, Krook-Riekkola A, Matosović M, A. Fokaides P, I. Ioannou B, Flamos A, Spyridaki N.  2018.  How are cities planning to respond to climate change? Assessment of local climate plans from 885 cities in the EU-28 Journal of Cleaner Production. doi: 10.1016/j.jclepro.2018.03.220. 191:207-219.
Simoes, S, Dias L, Gouveia JP, Seixas J, De Miglio R, A. C, M. G, Long G, Giannakidis G.  2018.  INSMART – Insights on integrated modelling of EU cities energy system transition. Energy Strategy Reviews. 20:150–155.
Gouveia, JP, Seixas J, Long G.  2018.  Mining households' energy data to disclose fuel poverty: Lessons for Southern Europe. Journal of Cleaner Production. 178:534-550. AbstractWebsite

Fuel poverty is a recognized and increasing problem in several European countries. A growing body of literature covers this topic, but dedicated analysis for Portugal are scarce despite the high perception of this condition. This paper contributes to fill this knowledge gap focusing on a European southern city while bringing new datasets and analysis to the assessment of this topic; consumer groups identification and to policy discussion. Daily electricity smart meters' registries were combined with socio-economic data, collected from door-to-door surveys, to understand the extent and the determinants of energy consumption for two contrasting consumer groups (herein called fuel poverty and fuel obesity groups). The analysis is based on the amount and annual profile of electricity consumption and was complemented with building energy simulations for relevant building typologies in those groups, to identify heating and cooling thermal performance gaps. The existence of these gaps allowed confirming and/or discarding the initial hypothesis of the poverty or obesity conditions. Results disclose socio-economic variables, as income, and consumers' behavior as key determinants of electricity consumption. It was identified a severe lack of thermal comfort levels inside households of both groups, either in cooling (98% for fuel poverty and 87% for fuel obesity) and heating seasons (98% for fuel poverty and 94% for fuel obesity). Major conclusion refers that electricity consumption cannot be used alone to segment consumer groups. This assessment may serve to support energy policy measures and instruments targeted to different consumers' groups. For example, distinct campaigns and differentiated incentives may apply to achieve energy efficiency and reduction while keep or improve indoor comfort levels.

Lopez, A, Bacelar R, Pires I, G.Santos T, PedroSousa J, Quintino L.  2018.  Non-destructive testing application of radiography and ultrasound for wire and arc additive manufacturing. Additive Manufacturing. 21:298-306. AbstractWebsite

The present work addressed the challenges of identifying applicable Non-Destructive Testing (NDT) techniques suitable for inspection and materials characterization techniques for Wire and Arc Additive Manufacturing (WAAM) parts. With the view of transferring WAAM to the industry and qualifying the manufacturing process for applications such as structural components, the quality of the produced parts needs to be assured. Thus, the main objective of this paper is to review the main NDT techniques and assess the capability of detecting WAAM defects, for inspection either in a monitoring, in-process or post-process scenario. Radiography and ultrasonic testing were experimentally tested on reference specimens in order to compare the techniques capabilities. Metallographic, hardness and electrical conductivity analysis were also applied to the same specimens for material characterization. Experimental outcomes prove that typical WAAM defects can be detected by the referred techniques. The electrical conductivity measurement may complement or substitute some destructive methods used in AM processing.

Seixas, J, Simoes SG, Fortes P, Gouveia J.  2018.  The pivotal role of electricity in the deep decarbonization of energy system: cost-effective options for Portugal. Limiting Global Warming to Well Below 2°C: Energy System Modelling and Policy Development. (Giannakidis G., K. Karlsson, M. Labriet, B. Ó Gallachóir, Eds.).: Springer, Lecture Notes in Energy 64. Springer International publishing, Doi: 10.1007/978-3-319-74424-7
Castro, NSS, Laia CAT, Maiti BK, Cerqueira N, Moura I, Carepo MSP.  2018.  Small phospho-donors phosphorylate MorR without inducing protein conformational changes. Biophys Chem. 240:25-33.
Braz, L, Grenha A, Corvo MC, Lourenço JP, Ferreira D, Sarmento B, da Costa ARM.  2018.  Synthesis and characterization of Locust Bean Gum derivatives and their application in the production of nanoparticles. Carbohydrate Polymers. 181:974–985.: Elsevier AbstractWebsite

The development of LBG-based nanoparticles intending an application in oral immunization is presented. Nanoparticle production occurred by mild polyelectrolyte complexation, requiring the chemical modification of LBG. Three LBG derivatives were synthesized, namely a positively charged ammonium derivative (LBGA) and negatively charged sulfate (LBGS) and carboxylate (LBGC) derivatives. These were characterized by Fourier-transform infrared spectroscopy, elemental analysis, nuclear magnetic resonance spectroscopy, gel permeation chromatography, and x-ray diffraction. As a pharmaceutical application was aimed, a toxicological analysis of the derivatives was performed by both MTT test and LDH release assay.

Several nanoparticle formulations were produced using LBGA or chitosan (CS) as positively charged polymers, and LBGC or LBGS as negatively charged counterparts, producing nanoparticles with adequate properties regarding an application in oral immunization.

Semeano, ATS, Maffei DF, Palma S, Li RWC, Franco BDGM, Roque ACA, Gruber J.  2018.  Tilapia fish microbial spoilage monitored by a single optical gas sensor. Food Control. 89:72-76. AbstractPDFWebsite

As consumption of fish and fish-based foods increases, non-destructive monitoring of fish freshness also becomes more prominent. Fish products are very perishable and prone to microbiological growth, not always easily detected by organoleptic evaluation. The analysis of the headspace of fish specimens through gas sensing is an interesting approach to monitor fish freshness. Here we report a gas sensing method for monitoring Tilapia fish spoilage based on the application of a single gas sensitive gel material coupled to an optical electronic nose. The optical signals of the sensor and the extent of bacterial growth were followed over time, and results indicated good correlation between the two determinations, which suggests the potential application of this simple and low cost system for Tilapia fish freshness monitoring.

Monteiro, P.  2018.  Uma análise comparativa de ferramentas de análise estática para deteção de erros de memória. FCT–NOVA. (António Ravara, João Lourenço, Eds.)., Lisboamon18.pdf
Maiti, BK, Maia L, Moro AJ, Lima JC, Cordas C, Moura I, Moura JJG.  2018.  Unusual reduction mechanism of copper in cysteine-rich environment. Inorg Chem. 57:8078-8088.Website
Cruz, J, Silva H, Lopes J, Rocha J, Jesus AP.  2018.  Very high fluence nitrogen implantations in metals studied by Rutherford Backscattering Spectrometry. :169-173.: Surface and Coatings Technology, 355surfcoattechnology-355-2018.pdf
dos Santos, LM, Ligabue R, Dumas A, Le Roux C, Micoud P, Meunier J-F, Martin F, Corvo M, Almeida P, Einloft S.  2018.  Waterborne polyurethane/Fe3O4-synthetic talc composites: synthesis, characterization, and magnetic properties. Polymer Bulletin. :1–16.: Springer Berlin Heidelberg AbstractWebsite

Nano-Fe3O4-synthetic talc gel was used as filler in the synthesis of waterborne polyurethane/Fe3O4-synthetic talc nanocomposites. This filler presents numerous edges (Si–O and Mg–O) and OH groups easily forming hydrogen bonds and polar interaction with water conferring hydrophilic character, consequently improving filler dispersion within a water-based matrix. Yet, the use of waterborne polyurethane (WPU) as matrix must be highlighted due to its environmentally friendly characteristics and low toxicity compared to solvent-based product. Fe3O4-synthetic talc-nanofillers were well dispersed into the polyurethane matrix even at high filler content as supported by XRD and TEM analyses. NMR indicates the interaction of filler OH groups with the matrix. For all nanocomposites, one can see a typical ferromagnetic behavior below Curie temperature (about 120 K) and a superparamagnetic behavior above this temperature. The use of Fe3O4-synthetic talc for obtaining magnetic nanocomposites resulted in improved materials with superior mechanical properties compared to solvent-based nanocomposites.

Dias, D, Lapa N, Bernardo M, Ribeiro W, Matos I, Fonseca I, Pinto F.  2018.  Cr(III) removal from synthetic and industrial wastewaters by using co-gasification chars of rice waste streams. Bioresource Technology. 266:139-150. AbstractWebsite

Blends of rice waste streams were submitted to co-gasification assays. The resulting chars (G1C and G2C) were characterized and used in Cr(III) removal assays from a synthetic solution. A Commercial Activated Carbon (CAC) was used for comparison purposes. The chars were non-porous materials mainly composed by ashes (68.3–92.6% w/w). The influences of adsorbent loading (solid/liquid ratio – S/L) and initial pH in Cr(III) removal were tested. G2C at a S/L of 5 mg L−1 and an initial pH of 4.50 presented an uptake capacity significantly higher than CAC (7.29 and 2.59 mg g−1, respectively). G2C was used in Cr(III) removal assays from an industrial wastewater with Cr(III) concentrations of 50, 100 and 200 mg L−1. Cr(III) removal by precipitation (uptake capacity ranging from 11.1 to 14.9 mg g−1) was more effective in G2C, while adsorption (uptake capacity of 16.1 mg g−1) was the main removal mechanism in CAC.

Surra, E, Bernardo M, Lapa N, Esteves I, Fonseca I, Mota JP.  2018.  Maize cob waste pre-treatments to enhance biogas production through co-anaerobic digestion with OFMSW. Waste Management. 72:193-205. AbstractWebsite

In the present work, the enhancement of biogas and methane yields through anaerobic co-digestion of the pre-hydrolised Organic Fraction of Municipal Solid Wastes (hOFMSW) and Maize Cob Wastes (MCW) in a lab-scale thermophilic anaerobic reactor was tested. In order to increase its biodegradability, MCW were submitted to an initial pre-treatment screening phase as follows: (i) microwave (MW) irradiation catalysed by NaOH, (ii) MW catalysed by glycerol in water and alkaline water solutions, (iii) MW catalysed by H2O2 with pH of 9.8 and (iv) chemical pre-treatment at room temperature catalysed by H2O2 with 4 h reaction time. The pre-treatments cataysed by H2O2 were performed with 2% MCW (wMCW/v alkaline water) at ratios of 0.125, 0.25, 0.5 and 1.0 (wH2O2/wMCW). The pre-treatment that presented the most favourable balance between sugars, lignin, cellulose and hemicellulose solubilisations, as well as low production of phenolic compound and furfural (inhibitors), was the chemical pre-treatment catalysed by H2O2, at room temperature, with a ratio of 0.5 wH2O2/wMCW (Pre1). This Pre1 was then optimised testing reaction times of 1, 2 and 3 days at a different pH (11.5) and MCW percentage (10% w/v). The optimised pre-treatment that presented the best results, considering the same criteria defined above, was the one carried out during 3 days, at pH 9.8 and 10% MCW w/v (Pre2). The anaerobic reactor was initially fed with the hOFMSW obtained from the hydrolysis tank of an industrial AD plant. The hOFMSW was than co-digested with MCW submitted to the pre-treatment Pre1. In another assay, hOFMSW was co-digested with MCW submitted pre-treatment Pre 2. The co-digestion of hOFMSW + Pre1 increased the biogas yield by 38.9% and methane yield by 29.7%, when compared to the results obtained with hOFMSW alone. The co-digestion of hOFMSW + Pre2 increased biogas yield by 46.0% and CH4 yield by 36.3%. In both cases, the methane content obtained in the biogas streams was above 66% v/v. These results show that pre-treatment with H2O2, at room temperature, is a promising low cost way to valorize MCW through co-digestion with hOFMSW.

Fernandes, SN, Lopes LF, Godinho MH.  2018.  Recent Advances in the Manipulation of Circularly Polarised Light with Cellulose Nanocrystal Films. Current Opinion in Solid State and Materials Science. Abstract
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Larsen, SR, Hansteen M, Pacakova B, Theodor K, Arnold T, Rennie AR, Helgesen G, Knudsen KD, Bordallo HN, Fossum JO, Cavalcanti LP.  2018.  Sample Cell for Studying Liquid Interfaces with an {\emph{in Situ}} Electric Field Using {{X}}-Ray Reflectivity and Application to Clay Particles at Oil–{}Oil Interfaces. Journal of Synchrotron Radiation. 25:915-917., Number 3 Abstract
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2017
Mendes, R, Pedrosa P, Lima {JC }, Fernandes {AR}, Baptista {PV}.  2017.  Photothermal enhancement of chemotherapy in breast cancer by visible irradiation of Gold Nanoparticles, sep. Scientific Reports. 7, Number 1: Nature Publishing Group Abstract

Photothermal Therapy (PTT) impact in cancer therapy has been increasing due to the enhanced photothermal capabilities of a new generation of nanoscale photothermal agents. Among these nanoscale agents, gold nanoshells and nanorods have demonstrated optimal properties for translation of near infra-red radiation into heat at the site of interest. However, smaller spherical gold nanoparticles (AuNPs) are easier to produce, less toxic and show improved photoconversion capability that may profit from the irradiation in the visible via standard surgical green lasers. Here we show the efficient light-to-heat conversion of spherical 14 nm AuNPs irradiated in the visible region (at the surface plasmons resonance peak) and its application to selectively obliterate cancer cells. Using breast cancer as model, we show a synergistic interaction between heat (photoconversion at 530 nm) and cytotoxic action by doxorubicin with clear advantages to those of the individual therapy approaches.

Chagas, R, Lourenco AM, Monteiro S, Ferreira RB, Ferreira LM.  2017.  Is caffeic acid, as the major metabolite present in Moscatel wine protein haze hydrolysate, involved in protein haze formation?, AUG FOOD RESEARCH INTERNATIONAL. 98:103-109., Number SI: Ctr Reference Educ & Res Viticulture & Oenol; Univ Appl Sci & Arts Western Switzerland; Canadian Inst Food Sci & Technol Abstract
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