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2024
Rippel, R, Ferreira LM, Branco PS.  2024.  Progress on the Synthesis and Applications of Aminals: Scaffolds for Molecular Diversity, 2024 JUN 10. SYNTHESIS-STUTTGART. Abstract
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Pinheiro, L, Freitas M, Branco PS.  2024.  Phosphate-Containing Glycolipids: A Review on Synthesis and Bioactivity. ChemMedChem. 19( ):e202400315.
Candeias, M, Moniz AB.  2024.  Public policies for Industry 4.0: some lessons from the Portuguese case. International Journal of Automotive Technology and Management. 24(2):144-168. AbstractWebsite

In Portugal, digital transition was structured with national public policies since 2003. In 2017, initiatives for the adoption of Industry 4.0 concepts are implemented in Portugal. We analysed the diffusion and implementation of these technologies, in Portugal. Some questions were raised: has the interplay between public policies, state agencies and industrial relations players in the process been articulated, as in Germany? What have been the effects of these technologies on workers and organisations? Are the public initiatives in place enough or more is needed? Qualitative and quantitative approaches were used to collect evidence on the main features and constraints of a public policy for Industry 4.0, based on the case study of the automotive sector in Portugal. Findings suggest the need to balance regulatory policies on data related risks, and investment policies towards education, training and organisational innovation are needed to complement technology development and adoption support.

Ferreira, MR, Morgado L, Salgueiro CA.  2024.  Periplasmic electron transfer network in Geobacter sulfurreducens revealed by biomolecular interaction studies. Protein Science. 33:e5082., Number 7 AbstractWebsite

Abstract Multiheme cytochromes located in different compartments are crucial for extracellular electron transfer in the bacterium Geobacter sulfurreducens to drive important environmental processes and biotechnological applications. Recent studies have unveiled that for particular sets of electron terminal acceptors, discrete respiratory pathways selectively recruit specific cytochromes from both the inner and outer membranes. However, such specificity was not observed for the abundant periplasmic cytochromes, namely the triheme cytochrome family PpcA-E. In this work, the distinctive NMR spectroscopic signatures of these proteins in different redox states were explored to monitor pairwise interactions and electron transfer reactions between each pair of cytochromes. The results showed that the five proteins interact transiently and can exchange electrons between each other revealing intra-promiscuity within the members of this family. This discovery is discussed in the light of the establishment of an effective electron transfer network by this pool of cytochromes. This network is advantageous to the bacteria as it enables the maintenance of the functional working potential redox range within the cells.

2023
Coelho, {BJ }, Pinto {JV }, Martins J, Rovisco A, Barquinha P, Fortunato E, Baptista {PV}, Martins R, Igreja R.  2023.  Parylene C as a Multipurpose Material for Electronics and Microfluidics, may. Polymers. 15, Number 10: MDPI - Multidisciplinary Digital Publishing Institute Abstract

Poly(p-xylylene) derivatives, widely known as Parylenes, have been considerably adopted by the scientific community for several applications, ranging from simple passive coatings to active device components. Here, we explore the thermal, structural, and electrical properties of Parylene C, and further present a variety of electronic devices featuring this polymer: transistors, capacitors, and digital microfluidic (DMF) devices. We evaluate transistors produced with Parylene C as a dielectric, substrate, and encapsulation layer, either semitransparent or fully transparent. Such transistors exhibit steep transfer curves and subthreshold slopes of 0.26 V/dec, negligible gate leak currents, and fair mobilities. Furthermore, we characterize MIM (metal–insulator–metal) structures with Parylene C as a dielectric and demonstrate the functionality of the polymer deposited in single and double layers under temperature and AC signal stimuli, mimicking the DMF stimuli. Applying temperature generally leads to a decrease in the capacitance of the dielectric layer, whereas applying an AC signal leads to an increase in said capacitance for double-layered Parylene C only. By applying the two stimuli, the capacitance seems to suffer from a balanced influence of both the separated stimuli. Lastly, we demonstrate that DMF devices with double-layered Parylene C allow for faster droplet motion and enable long nucleic acid amplification reactions.

Rafique, A, Carmo J, Marques A, Ferreira I, Baptista A.  2023.  PEDOT:PSS Electrospray Functionalization of Carbon Yarns for Integration in Flexible Fibre-Shaped Supercapacitors, 3-6 April. XXI Congresso da Sociedade Portuguesa de Materiais and XII International Symposium on Materials. , Guimarães
2022
Gago, D, Corvo MC, Chagas R, Ferreira LM, Coelhoso I.  2022.  Protein Adsorption Performance of a Novel Functionalized Cellulose-Based Polymer, DEC. POLYMERS. 14, Number 23 Abstract

Dicarboxymethyl cellulose (DCMC) was synthesized and tested for protein adsorption. The prepared polymer was characterized by inductively coupled plasma atomic emission spectrometry (ICP-AES), attenuated total reflection Fourier-transform infrared spectroscopy (ATR-FTIR) and solid state nuclear magnetic resonance (ssNMR) to confirm the functionalization of cellulose. This work shows that protein adsorption onto DCMC is charge dependent. The polymer adsorbs positively charged proteins, cytochrome C and lysozyme, with adsorption capacities of 851 and 571 mg g(-1), respectively. In both experiments, the adsorption process follows the Langmuir adsorption isotherm. The adsorption kinetics by DCMC is well described by the pseudo second-order model, and adsorption equilibrium was reached within 90 min. Moreover, DCMC was successfully reused for five consecutive adsorption-desorption cycles, without compromising the removal efficiency (98-99%).

Haque, S, Alexandre M, Baretzky C, Rossi D, Rossi FD, Vicente AT, Brunetti F, Águas H, Ferreira RAS, Fortunato E, Maur MAD, Wurfel U, Martins R, Mendes MJ.  2022.  Photonic-Structured Perovskite Solar Cells: Detailed Optoelectronic Analysis. ACS Photonics. 9(7):2408–2421.
2021
Sine, A, Pimentel M, Nunes S.  2021.  Punching Shear Tests on RC Flat Slabs Strengthened with an UHPFRC Layer, 2021. fib Symposium 2021. , Lisbonsine-fib2021_169_punching.pdf
Mouquinho, A, Sanchez-Sobrado O, Haque S, Centeno P, Alexandre MF, Ribeiro G, Boane JLN, Mateus T, Menda UD, Águas H, Fortunato E, Martins R, Mendes MJ.  2021.  Photonic Strategies for Photovoltaics: New Advances Beyond Optics. Modern Environmental Science and Engineering. 7(7):642-652.
Matos, MJB, Trovão F, Gonçalves J, Rothbauer U, Freire MG, Barbosa AMJB, Pina AS, Roque ACA.  2021.  A purification platform for antibodies and derived fragments using a de novo designed affinity adsorbent. Separation and Purification Technology. 265
Polino, M, Rho HS, Pina MP, Mallada R, Carvalho AL, Romão MJ, Coelhoso I, Gardeniers JGE, Crespo JG, Portugal CAM.  2021.  Protein Crystallization in a Microfluidic Contactor with Nafion®117 Membranes. Membranes. 11, Number 8 AbstractWebsite

Protein crystallization still remains mostly an empirical science, as the production of crystals with the required quality for X-ray analysis is dependent on the intensive screening of the best protein crystallization and crystal’s derivatization conditions. Herein, this demanding step was addressed by the development of a high-throughput and low-budget microfluidic platform consisting of an ion exchange membrane (117 Nafion® membrane) sandwiched between a channel layer (stripping phase compartment) and a wells layer (feed phase compartment) forming 75 independent micro-contactors. This microfluidic device allows for a simultaneous and independent screening of multiple protein crystallization and crystal derivatization conditions, using Hen Egg White Lysozyme (HEWL) as the model protein and Hg2+ as the derivatizing agent. This microdevice offers well-regulated crystallization and subsequent crystal derivatization processes based on the controlled transport of water and ions provided by the 117 Nafion® membrane. Diffusion coefficients of water and the derivatizing agent (Hg2+) were evaluated, showing the positive influence of the protein drop volume on the number of crystals and crystal size. This microfluidic system allowed for crystals with good structural stability and high X-ray diffraction quality and, thus, it is regarded as an efficient tool that may contribute to the enhancement of the proteins’ crystals structural resolution.

Fernandes, TM, Morgado L, Turner DL, Salgueiro CA.  2021.  Protein Engineering of Electron Transfer Components from Electroactive Geobacter Bacteria. Antioxidants. 10, Number 6 AbstractWebsite

Electrogenic microorganisms possess unique redox biological features, being capable of transferring electrons to the cell exterior and converting highly toxic compounds into nonhazardous forms. These microorganisms have led to the development of Microbial Electrochemical Technologies (METs), which include applications in the fields of bioremediation and bioenergy production. The optimization of these technologies involves efforts from several different disciplines, ranging from microbiology to materials science. Geobacter bacteria have served as a model for understanding the mechanisms underlying the phenomenon of extracellular electron transfer, which is highly dependent on a multitude of multiheme cytochromes (MCs). MCs are, therefore, logical targets for rational protein engineering to improve the extracellular electron transfer rates of these bacteria. However, the presence of several heme groups complicates the detailed redox characterization of MCs. In this Review, the main characteristics of electroactive Geobacter bacteria, their potential to develop microbial electrochemical technologies and the main features of MCs are initially highlighted. This is followed by a detailed description of the current methodologies that assist the characterization of the functional redox networks in MCs. Finally, it is discussed how this information can be explored to design optimal Geobacter-mutated strains with improved capabilities in METs.

2020
Ribeiro, SO, Almeida PL, Pires J, de Castro B, Balula SS.  2020.  Polyoxometalate@Periodic mesoporous organosilicas as active materials for oxidative desulfurization of diesels, {AUG 1}. Microporous and Mesoporous Materials. 302:110193. AbstractWebsite

Novel material catalysts based in the active zinc-substituted polyoxotungstate ({[}PW11Zn(H2O)(39)](5-), abbreviated as PW11Zn) were efficiently used in the oxidative desulfurization of real and model diesels. These active catalytic center was strategically immobilized in a less hydrophilic periodic mesoporous organosilicas (PMOs), containing ethane-bridge (PMOE) and benzene-bridge (PMOB) walls, functionalized with (3-aminopropyl)triethoxysilane (aptes). The efficiency of the novel catalytic composites (PW11Zn@aptesPMOE and PM11Zn@aptesPMOB) was studied under oxidative desulfurization system (CODS) without the presence of an extraction solvent and also using a biphasic (diesel/extraction solvent) oxidative desulfurization system (ECODS). Both composites presented higher desulfurization efficiency under the solvent-free system, reaching ultra-low levels of sulfur compounds after only 1 h and using low ratio of H2O2/S = 4. The catalysts could be recycled without loss of activity for ten consecutive cycles. However, after the first desulfurization cycle complete desulfurization was achieved within only 30 min using PW11Zn@aptesPMOE composite. Also, the structure of PW it Zn@aptesPMOE demonstrated to be more stable than PW11Zn@aptesPMOB, probably due to the occurrence of some PW11Zn leaching from the PMOB surface, probably caused by the lower interaction of PW11Zn with the benzene-bridge PMOB wall. The most robust catalyst PW11Zn@aptesPMOE was used to desulfurize a real diesel achieving 75.9% of desulfurization after 2 h. The catalyst was further recycled with success to treat real diesel.

Martins, C, Rodrigo {AP }, Madeira C, D'Ambrosio M, Goncalves C, Parola {AJ }, Grosso {AR }, Baptista {PV }, Fernandes {AR }, Costa {PM }.  2020.  Porphyrin Pigments in Polychaeta: Explorations on the Evolution of Haem Metabolism in Marine Eumetazoans, jan. 18 Abstract
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Trindade, AC, Carreto M, Helgesen G, Knudsen KD, Puchtler F, Breu J, Fernandes S, Godinho MH, Fossum JO.  2020.  Photonic composite materials from cellulose nanorods and clay nanolayers, 2020. 229(17):2741-2755. AbstractWebsite

Cellulose nano crystals (CNCs) are promising materials for energy efficient buildings related to the control of reflectivity and heat absorption/reflection of light. In this sense it is important to improve CNCs films fire retardant properties, which can be achieved by adding clays. Cellulose nanocrystals (CNCs) and nanolayers obtained from Sodium Fluorohectorite (NaFh) synthetic clay are both known to form liquid crystalline phases in aqueous suspensions. CNCs form cholesteric phases, which structure is preserved after water evaporation, while dry NaFh nanolayers aligned films collapse. In this initial work, it is shown that CNCs are compatible with NaFh clay. We demonstrate that the liquid crystalline phase of CNCs in water is not destroyed by the presence of NaFh nanolayers. The NaFh nanolayers act as planar anchoring surfaces to the cellulose nanorods and, after evaporation of the water coloured films are obtained. The precursor solutions and the photonic films were investigated by Describe several techniques.

Chagas, R, Silva PES, Fernandes SN, Žumer S, Godinho MH.  2020.  Playing the blues, the greens and the reds with cellulose-based structural colours, 2020. Faraday Discussions. 223:247-260.: The Royal Society of Chemistry AbstractWebsite

Structural vivid colours can arise from the interference of light reflected from structures exhibiting periodicity on scales in the range of visible wavelengths. This effect is observed with light reflected from cell-walls of some plants and exoskeletons of certain insects. Sometimes the colour sequence observed for these structures consists of nearly circular concentric rings that vary in colour from Red, Orange, Yellow, Green, Cyan to Blue, from the periphery to the centre, similarly to the colour scheme sequence observed for the rainbow (ROYGB). The sequence of colours has been found for solid films obtained from droplets of aqueous cellulose nanocrystals (CNCs) suspensions and attributed to a “coffee ring” effect. In this work, coloured lyotropic solutions and solid films obtained from a cellulose derivative in the presence of trifluoroacetic acid (TFA), which acts as a “reactive solvent”, are revisited. The systems were investigated with spectroscopy, using circularly and linearly polarised light, coupled with a polarised optical microscope (POM) and scanning electron microscopy (SEM). The lyotropic cholesteric liquid crystalline solutions were confined in capillaries to simplify 1D molecular diffusion along the capillary where an unexpected sequence of the structural colours was observed. The development and reappearance of the sequence of vivid colours seem consistent with the reaction–diffusion of the “reactive solvent” in the presence of the cellulosic chains. The strong TFA acts as an auto-catalyst for the chemical reaction between TFA and the hydroxyl groups, existing along the cellulosic chain, and diffuses to the top and bottom along the capillaries, carrying dissolved cellulosic chains. Uncovering the precise mechanism of colour sequence and evolution over time in cellulosic lyotropic solutions has important implications for future optical/sensors applications and for the understanding of the development of cellulose-based structures in nature.

Pacheco, V, Araújo N, Rocha L.  2020.  PRODUTECH SIF Project: its mobilized effect and main results and its contribution to accelerating digital transformation in the industry, 2-4 Oct. 2020. 8th International Conference on Virtual and Networked Organizations Emergent Technologies and Tools - ViNOrg'20. , Guimarães, Portugal: Universidade do Minho
Olalla, S-S, Mendes MJ, Mateus T, Costa J, Nunes D, Águas H, Fortunato E, Martins R.  2020.  Photonic-structured TCO front contacts yielding optical and electrically enhanced thin-film solar cells. Solar Energy. 196(15):92-98.
Honnet, C, Perner-Wilson H, Teyssier M, Fruchard B, Steimle J, Baptista AC, Strohmeier P.  2020.  PolySense: Augmenting Textiles with Electrical Functionality using In-Situ Polymerization. Proceedings of the 2020 CHI Conference on Human Factors in Computing Systems.
Strohmeier, P, Honnet C, Pernet-Wilson H, Teyssier M, Fruchard B, Baptista AC, Steimle J.  2020.  PolySense: How to Make Electrically Functional Textiles. CHI Conference on Human Factors in Computing Systems .
Sousa, EHS, Diógenes ICN, Lopes LGF, Moura JJG.  2020.  Potential therapeutic approaches for a sleeping pathogen: tuberculosis a case for bioinorganic chemistry. J Biol Inorg Chem. 25:685.
Gavinho, SR, Soares MC, Borges JB, Silva JC, Nogueira ISá, Graça MP.  2020.  Preparation and Characterization of Zinc and Magnesium Doped Bioglasses. Nanoscience and Nanotechnology in Security and Protection against CBRN Threats. :465-475. AbstractWebsite

Peri-implantitis is an infectious disease that affects about one of five patients who receive a dental implant within 5 years after the surgery. To minimize this reaction the development of new biomaterials with antibacterial action is needed that can be used as a coating material in orthodontic implants. In addition, these biomaterials can be doped with several ions, which add specific properties that may act at the cellular level, such as increasing the angiogenesis efficiency. In this work, 45S5 Bioglass® has been used as the base material because it presents higher bioactivity compared to other biomaterials. To add antibacterial function and increase positive effects on bone metabolism, zinc and magnesium ions were introduced in the glass network. The main objective was the synthesis of the 45S5 glass by melt-quenching and study the biological performance as function of the zinc and magnesium concentrations. The structural and biological properties of the prepared samples are discussed.

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