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2019
Vilarigues, M, Coutinho I, Medici T, Alves LC, Gratuze B, Machado A.  2019.  From beams to glass: determining compositions to study provenance and production techniques. Physical Sciences Reviews. :1-24.
Pinto, CAM, Palomar T, Alves LC, da Silva SHM, Monteiro RC, Macedo MF, Vilarigues MG.  2019.  Fungal biodeterioration of stained-glass windows in monuments from Belém do Pará (Brazil). International Biodeterioration & Biodegradation. 138:106-113. AbstractWebsite

The most prominent historical buildings in Belém do Pará (Northern Brazil) have modernist stained-glass windows, which were commissioned from Europe since the end of the 19th century. Some of them present biodegradation; however, there is no information about the microbial activity on them. The present work is focused on the biodeterioration by fungi on some of these Modern stained-glass windows. The fungal communities were collected, isolated and then identified by means of molecular methods. Additionally, a laboratory-based biodeterioration experiment was carried out to assess the fungal activity on replica glass samples with three different chemical compositions. The replica samples were inoculated with a four-fungal species mixture and incubated under optimal growth conditions for 5 months. Optical microscopy, μ-PIXE, SEM-EDS and FTIR-ATR were performed to evaluate the biodeterioration of the soda-lime silicate glasses. This multidisciplinary approach showed that the inoculated spores (Aspergillus arenarioides, Fusarium oxysporum, Hortaea werneckii, and Trichoderma longibrachiatum) were able to form substantial mycelia in all replica glass samples. The main alterations observed were small crystals, hyphae fingerprints and a slight decrease on the glass surface smoothness. Despite the aforementioned damages, the soda-lime silicate glass compositions showed high resistance against the inoculated fungal species.

2018
Leisico, F, V. Vieira D, Figueiredo TA, Silva M, Cabrita EJ, Sobral RG, Ludovice AM, Trincão J, Romão MJ, de Lencastre H, Santos-Silva T.  2018.  First insights of peptidoglycan amidation in Gram-positive bacteria - the high-resolution crystal structure of Staphylococcus aureus glutamine amidotransferase GatD, 2018. Scientific Reports. 8(1):5313. AbstractWebsite

Gram-positive bacteria homeostasis and antibiotic resistance mechanisms are dependent on the intricate architecture of the cell wall, where amidated peptidoglycan plays an important role. The amidation reaction is carried out by the bi-enzymatic complex MurT-GatD, for which biochemical and structural information is very scarce. In this work, we report the first crystal structure of the glutamine amidotransferase member of this complex, GatD from Staphylococcus aureus, at 1.85 Å resolution. A glutamine molecule is found close to the active site funnel, hydrogen-bonded to the conserved R128. In vitro functional studies using 1H-NMR spectroscopy showed that S. aureus MurT-GatD complex has glutaminase activity even in the absence of lipid II, the MurT substrate. In addition, we produced R128A, C94A and H189A mutants, which were totally inactive for glutamine deamidation, revealing their essential role in substrate sequestration and catalytic reaction. GatD from S. aureus and other pathogenic bacteria share high identity to enzymes involved in cobalamin biosynthesis, which can be grouped in a new sub-family of glutamine amidotransferases. Given the ubiquitous presence of GatD, these results provide significant insights into the molecular basis of the so far undisclosed amidation mechanism, contributing to the development of alternative therapeutics to fight infections.

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.
Carvalho, LC, Queda F, Almeida CV, Filipe SR, Marques MMM.  2018.  From a natural polymer to relevant NAG-NAM precursors. Asian J Org Chem.. 7(12):2544-2551.
Echeverria, C, Fernandes SN, Godinho MH, Borges JB, Soares PIP.  2018.  Functional Stimuli-Responsive Gels: Hydrogels and Microgels. Gels. 4(2):54. AbstractWebsite

One strategy that has gained much attention in the last decades is the understanding and further mimicking of structures and behaviours found in nature, as inspiration to develop materials with additional functionalities. This review presents recent advances in stimuli-responsive gels with emphasis on functional hydrogels and microgels. The first part of the review highlights the high impact of stimuli-responsive hydrogels in materials science. From macro to micro scale, the review also collects the most recent studies on the preparation of hybrid polymeric microgels composed of a nanoparticle (able to respond to external stimuli), encapsulated or grown into a stimuli-responsive matrix (microgel). This combination gave rise to interesting multi-responsive functional microgels and paved a new path for the preparation of multi-stimuli “smart” systems. Finally, special attention is focused on a new generation of functional stimuli-responsive polymer hydrogels able to self-shape (shape-memory) and/or self-repair. This last functionality could be considered as the closing loop for smart polymeric gels.

2017
Delgado-Lima, A, Borges JP, Ferreira I, Machado A.  2017.  Fluorescent and conductive cellulose acetate-based membranes with porphyrins. Materials today Communications. 11:26-37. AbstractWebsite

The unique properties of electrospun nanofibers combined with functional compounds allow the preparation of novelty materials that can be employed in a wide range of applications. Among a vast number of polymers, Cellulose Acetate (CA) it is considered easy to electrospun and it was employed as the polymeric matrix, where free and iridium-porphyrins were incorporated. Two different solvent systems were employed according to the porphyrin used, and the best dispersion level on both the electrospun solution and the membranes, was achieved with the iridium porphyrin. The nanofibers with this porphyrin also exhibited electrical properties, while the fluorescence was quenched by the presence of specific axial ligands.

Delgado-Lima, A, Borges JP, Ferreira IM, Machado AV.  2017.  Fluorescent and conductive cellulose acetate-based membranes with porphyrins. Materials Today Communications. 11:26-37. AbstractWebsite

The unique properties of electrospun nanofibers combined with functional compounds allow the preparation of novelty materials that can be employed in a wide range of applications. Among a vast number of polymers, Cellulose Acetate (CA) it is considered easy to electrospun and it was employed as the polymeric matrix, where free and iridium-porphyrins were incorporated. Two different solvent systems were employed according to the porphyrin used, and the best dispersion level on both the electrospun solution and the membranes, was achieved with the iridium porphyrin. The nanofibers with this porphyrin also exhibited electrical properties, while the fluorescence was quenched by the presence of specific axial ligands.

Dias, AMGC, Roque ACA.  2017.  The future of protein scaffolds as affinity reagents for purification. Biotechnology and Bioengineering. 114:481–491., Number 3 Abstract

Affinity purification is one of the most powerful separation techniques extensively employed both at laboratory and production scales. While antibodies still represent the gold standard affinity reagents, others derived from non-immunoglobulin scaffolds emerged as interesting alternatives in particular for affinity purification. The lower costs of production, fast ligand development and high robustness are appealing advantages of non-immunoglobulin scaffolds. These have successfully been used in the affinity purification of relevant targets as antibodies, human serum albumin, transferrin and other biomarkers, as reviewed in this work. Furthermore, a critical assessment on the strengths, weaknesses, opportunities and threats related with the implementation of non-immunoglobulin scaffolds as ligands in affinity purification are discussed. This article is protected by copyright. All rights reserved.

2016
Gouveia, JP, Seixas J.  2016.  Fuel Poverty and Fuel Obesity: what smart meters tell us, 26-29 June . International Society for Ecological Economics Conference. , Washington D.C., USA
Montagner, C, Jesus R, Correia N, Vilarigues M, Macedo R, Melo MJ.  2016.  Features combination for art authentication studies: brushstroke and materials analysis of Amadeo de Souza-Cardoso, 2016. Multimedia Tools and Applications. 75(7):4039-4063. AbstractWebsite
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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
2015
Veigas, B, Baptista {PMRV}, Fortunato E.  2015.  Field Effect Sensors for Nucleic Acid Detection: Recent Advances and Future Perspectives, may. Sensors. 15:10380–10398., Number 5: MDPI - Multidisciplinary Digital Publishing Institute Abstract

In the last decade the use of field-effect-based devices has become a basic structural element in a new generation of biosensors that allow label-free DNA analysis. In particular, ion sensitive field effect transistors (FET) are the basis for the development of radical new approaches for the specific detection and characterization of DNA due to FETs' greater signal-to-noise ratio, fast measurement capabilities, and possibility to be included in portable instrumentation. Reliable molecular characterization of DNA and/or RNA is vital for disease diagnostics and to follow up alterations in gene expression profiles. FET biosensors may become a relevant tool for molecular diagnostics and at point-of-care. The development of these devices and strategies should be carefully designed, as biomolecular recognition and detection events must occur within the Debye length. This limitation is sometimes considered to be fundamental for FET devices and considerable efforts have been made to develop better architectures. Herein we review the use of field effect sensors for nucleic acid detection strategiesfrom production and functionalization to integration in molecular diagnostics platforms, with special focus on those that have made their way into the diagnostics lab.

Gago, S, Basilio N, Moro AJ, Pina F.  2015.  Flavylium based dual photochromism: addressing cis-trans isomerization and ring opening-closure by different light inputs, 2015. Chemical Communications. 51(34):7349-7351. AbstractWebsite
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Cardoso, BD, Vicente AI, Ward JBJ, Sebastiao PJ, Chavez FV, Barroso S, Carvalho A, Keely SJ, Martinho PN, Calhorda MJ.  2015.  Fe(III) salEen derived Schiff base complexes as potential contrast agents. Inorganica Chimica Acta. 432:258-266. AbstractWebsite

Three iron(III) complexes with ligands derived from N-ethyl-N-(2-aminoethyl) salicylaldiminate (H, 1; 5-Br, 2; 3-OMe, 3 substituents at the phenyl group) were prepared and the X-ray crystal structures of 1 and 2 are reported. NMR studies of solutions of these complexes in DMSO allowed for investigation of their magnetic behaviour and paramagnetic relaxation contribution. The relaxivities measured ranged from 0.35 to 0.80 mM(-1) s(-1) for proton Larmor frequencies from 0.01 to 300 MHz, in agreement with those known for other iron(III) based contrast agents. Biological studies on colonic epithelial T-84 cell monolayers showed that the compounds exert toxic effects only at concentrations higher than 100 mu M while coincidently reducing colonic epithelial secretory function. These two features make these complexes good candidates for further development in order to be used as MRI contrast agents. (C) 2015 Elsevier B.V. All rights reserved.

Gago, S, Basilio N, Moro AJ, Pina F.  2015.  Flavylium based dual photochromism: addressing cis-trans isomerization and ring opening-closure by different light inputs. Chemical Communications. 51:7349-7351., Number 34 AbstractWebsite
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Fundo, JF, Amaro AL, Madureira AR, Carvalho A, Feio G, Silva CLM, Quintas MAC.  2015.  Fresh-cut melon quality during storage: An NMR study of water transverse relaxation time. Journal of Food Engineering. 167:71-76. AbstractWebsite

Molecular mobility is a fundamental parameter which reflects the dynamic properties of food components and contributes to food degradation reactions comprehension. Fresh-cut fruits have become an important food market segment. However, processing of fruits promotes faster its physiological deterioration, biochemical changes and microbial degradation. The purpose of this work was to use NMR methodology as a tool to evaluate fresh-cut fruit quality, during storage at refrigerated conditions. The fresh-cut melon transverse relaxation time (T-2) was measured for a period of 7 days of storage at 5 degrees C. The relationship between the obtained values, microstructure and quality parameters was investigated. In general, results show the existence of one class of water fluidity in the system, the one present in cells after processing. T-2, a measure of this fluidity, is affected by the processing and storage time. Also, it is possible to find a close relationships between T-2 and quality parameters of total colour difference (TCD), firmness and a(w). As T-2 increases TCD also increases, while firmness and aw decrease. These results highlight the usefulness of NMR methodology application in food science. (C) 2015 Elsevier Ltd. All rights reserved.

2014
Santos, TG, Miranda RM, Vilaça P.  2014.  Friction Stir Welding assisted by electrical Joule effect, 2014. Journal of Materials Processing Technology. 214(10):2127-2133.: Elsevier Ltd AbstractWebsite
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Santos, TG, Miranda RM, Vilaça P.  2014.  Friction stir welding assisted by electrical joule effect to overcome lack of penetration in aluminium alloys, 2014. 17th Conference of the European Scientific Association on Material Forming, ESAFORM 2014. 611-612:763-772., Espoo: Trans Tech Publications Ltd AbstractWebsite
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Rodrigues, A, Gutierrez-Patricio S, Miller AZ, Saiz-Jimenez C, Wiley R, Nunes D, Vilarigues M, Macedo MF.  2014.  Fungal biodeterioration of stained-glass windows, 2014. International Biodeterioration and Biodegradation. 90:152-160. AbstractWebsite
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Ruivo, A, Andrade S, Rocha J, Laia C, Pina F.  2014.  Formation of Photoluminescent Lead Bromide Nanoparticles on Aluminoborosilicate Glass. Journal of Physical Chemistry C. (118):12436–12442.
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.

Sequeira, SO, Cabrita EJ, Macedo MF.  2014.  Fungal Biodeterioration of Paper: How are Paper and Book Conservators Dealing with it? An International Survey Restaurator. International Journal for the Preservation of Library and Archival Material. 35(2):181–199. Abstract

Paper biodeterioration by fungi has always been a concern in archives, libraries and museums. Several guidelines have been published regarding the prevention of fungal development in paper collections and recovery of affected objects, but what is actually being implemented from the literature by worldwide paper and book conservators? How common is this type of biodeterioration? What needs to be further studied? In order to access this information we conducted an online international questionnaire with participants from 20 different countries. The results show that fungal biodeterioration is highly common in paper collections. All of the respondents already had to deal with paper deteriorated by fungi, and although the vast majority uses active measures to prevent fungal development, most of them have already experienced active fungal infestations. The mainly used preventive measures are the ones concerned with the control of the environmental conditions in storage and display rooms. Drying the affected paper objects and applying 70% ethanol are the most preferred options to stop active fungal growth. The study of non-toxic and safer antifungals is considered here as the most relevant research topic in the area of paper biodeterioration by fungi, meaning that the options currently available are not totally satisfactory.