118 results on '"Costa, Mafalda"'
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2. Personal adornments in West-Central Africa—the case study of a talc bead from the Kongo Kingdom (Mbanza Kongo, Angola)
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Costa, Mafalda, Barrulas, Pedro, Lopes, Maria da Conceição, Barreira, João, de Jesus, Maria da Piedade, da Silva Domingos, Sónia, Vandenabeele, Peter, and Mirão, José
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- 2023
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3. Understanding the chemical and mineralogical composition of commercial henna and jagua tattoos and dyes—a multi-analytical approach
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Rubio, Laura, Costa, Mafalda, Barrulas, Pedro, Lores, Marta, Garcia-Jares, Carmen, and Barrocas-Dias, Cristina
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- 2022
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4. New approaches for the study of faience using beads from Southern Portugal
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Costa, Mafalda, Barrulas, Pedro, Arruda, Ana Margarida, Barbosa, Rui, Vandenabeele, Peter, and Mirão, José
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- 2022
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5. Blue shadows of Roman glass artefacts
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Medeghini, Laura, Botticelli, Michela, Cadena-Irizar, Ana C., Lepri, Barbara, Ferrandes, Antonio F., Costa, Mafalda, and Barrulas, Pedro
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- 2022
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6. Optimization of the Application of Commercial Hydrophobic Coatings for Natural Stone Protection and Preservation.
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Hashim, Hurraira, Dias, Luís, Martins, Sérgio, Pires, Vera, Costa, Mafalda, and Barrulas, Pedro
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STONE ,PROTECTIVE coatings ,SUBSTRATES (Materials science) ,SURFACE coatings ,SILANE - Abstract
Natural stone has been used worldwide in the construction of archaeological and historical heritage. However, its preservation continues to be threatened by weathering and degradation phenomena. Water is widely recognized as the most threatening external component that contributes to stone deterioration, increasing the need for the development of protective hydrophobic coatings to eliminate water penetration. This study intends to contribute to the better understanding of natural stone treatment strategies to prevent water penetration and subsequent stone alteration by studying the effect of coating and stone substrate temperatures, and the number of coating applications, on the effectiveness, compatibility, and durability of commercial hydrophobic coatings. The results obtained revealed that while more than one application increases coating hydrophobic effectiveness, it frequently leads to changes in the aesthetic appearance of natural stone, including whitening and darkening of the substrate's original hues. Improved hydrophobic effectiveness (maximum gain of ≈ 9%) is also achieved when applying the commercial coatings at 4 °C to natural stone substrates maintained at room temperature, conditions that are feasible to be used in real life. Additionally, the commercial coating composed of silane/siloxane with modified fluorinated additives was found to be the most effective and durable hydrophobic solution. [ABSTRACT FROM AUTHOR]
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- 2024
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7. Modern Muralists in the Spotlight: Technical and Material Characteristics of the 1946–1949 Mural Paintings by Almada Negreiros in Lisbon (Part1).
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Gil, Milene, Cardoso, Inês, Costa, Mafalda, and Frade, José C.
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MURAL art ,MICROSCOPY ,SCANNING electron microscopy ,FOURIER transforms - Abstract
This paper presents the first insight into how Almada Negreiros, a key artist of the first generation of modernism in Portugal, created his mural painting masterpiece in the maritime station of Rocha do Conde de Óbidos in Lisbon. This set of six monumental mural paintings dates from 1946 to 1949 and is considered Almada's artistic epitome. As part of the ALMADA project: Unveiling the mural painting art of Almada Negreiros, the murals are being analyzed from a technical and material perspective to understand his modus operandi and the material used. This is the first study of this nature carried out on site and in the laboratory using standard and more advanced imaging, non-invasive analysis, and microanalysis techniques. This article reports the results obtained with visual examination, technical photography in visible (Vis), visible raking (Vis-Rak), complemented by 2D and 3D optical microscopy (OM), scanning electron microscopy with energy-dispersive spectrometry (SEM-EDS), and Fourier transform infrared micro-spectroscopy (µ-FTIR) of the paint layers. The results show the similarities, differences, and technical difficulties that the painter may have had when working on the first, third, and presumably last mural to be painted. Vis-Rak light images were particularly useful in providing a clear idea of how the work progressed from top to bottom through large sections of plaster made with lime mortars. It also revealed an innovative pounced technique used by Almada Negreiros to transfer the drawings in full scale to the walls. Other technical characteristics highlighted by the analytical setup are the use of textured, opaque, and transparent paint layers. The structure of the paintings does not follow a rigid build-up from light to dark, showing that the artist freely adapted according to the motif represented. As far as the colour palette is concerned, Almada masterfully uses primary and complementary colours made with Fe-based pigments and with synthetic ultramarine blue, cadmium pigments, and emerald green. [ABSTRACT FROM AUTHOR]
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- 2024
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8. Determining the provenance of the European glass beads of Lumbu (Mbanza Kongo, Angola)
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Costa, Mafalda, Barrulas, Pedro, Dias, Luís, Lopes, Maria da Conceição, Barreira, João, Clist, Bernard, Karklins, Karlis, de Jesus, Maria da Piedade, da Silva Domingos, Sónia, Moens, Luc, Vandenabeele, Peter, and Mirão, José
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- 2020
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9. Biosynthesis of mycobacterial methylmannose polysaccharides requires a unique 1- O -methyltransferase specific for 3- O -methylated mannosides
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Ripoll-Rozada, Jorge, Costa, Mafalda, Manso, José A., Maranha, Ana, Miranda, Vanessa, Sequeira, André, Ventura, M. Rita, Macedo-Ribeiro, Sandra, Pereira, Pedro José Barbosa, and Empadinhas, Nuno
- Published
- 2019
10. Correction to: First insights into the archaeometric analysis of the Los Amores Mosaic in Cástulo (Linares, Spain): the Judgement of Paris
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Sánchez, Alberto, Tuñón, José, Montejo, Manuel, Amate, Pilar, Ceprián, Bautista, Rousaki, Anastasia, Costa, Mafalda, Saelens, Delphine, Lycke, Sylvia, and Vandenabeele, Peter
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- 2021
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11. First insights into the archaeometric analysis of the Los Amores Mosaic in Cástulo (Linares, Spain): the Judgement of Paris
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Sánchez, Alberto, Tuñón, José, Montejo, Manuel, Amate, Pilar, Ceprián, Bautista, Rousaki, Anastasia, Costa, Mafalda, Saelens, Delphine, Lycke, Sylvia, and Vandenabeele, Peter
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- 2021
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12. Chasing a ghost: notes on the present distribution and conservation of the sooty mangabey (Cercocebus atys) in Guinea-Bissau, West Africa
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Ferreira da Silva, Maria Joana, Paddock, Christina, Gerini, Federica, Borges, Filipa, Aleixo-Pais, Isa, Costa, Mafalda, Colmonero-Costeira, Ivo, Casanova, Catarina, Lecoq, Miguel, Silva, Cristina, Bruford, Michael W., Varanda, Jorge, and Minhós, Tânia
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- 2020
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13. An insight into the provenance of the Phoenician-Punic glass beads of the necropolis of Vinha das Caliças (Beja, Portugal)
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Costa, Mafalda, Barrulas, Pedro, Arruda, Ana Margarida, Dias, Luís, Barbosa, Rui, Vandenabeele, Peter, and Mirão, José
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- 2021
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14. Multi-analytical approach to the study of the European glass beads found in the tombs of Kulumbimbi (Mbanza Kongo, Angola)
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Costa, Mafalda, Barrulas, Pedro, Dias, Luís, da Conceição Lopes, Maria, Barreira, João, Clist, Bernard, Karklins, Karlis, da Piedade de Jesus, Maria, da Silva Domingos, Sónia, Vandenabeele, Peter, and Mirão, José
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- 2019
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15. "What do they mean?" a systematic review on the interpretation, usage and acceptability of "they".
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da Costa, Mafalda Batista, Tenenbaum, Harriet R., and Grandison, Alexandra
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NONBINARY people ,FEMINISM ,GENDER-neutral language ,PRONOUNS (Grammar) - Abstract
The rise of feminist and LGBTQIA+ movements paved the way for many equality reforms. These include language reforms, which facilitate inclusion of multiple groups in society. For example, the shift from the generic "he" to "he or she" and "they" allows for the inclusion of women, transgender, and non-binary individuals in many narratives. For this reason, many institutions worldwide encourage neutral language. It remains unclear how individuals interpret neutral language. One case of neutral language is the pronoun "they," which has been assigned multiple definitions from the 1970s to 2022. We examine how the pronoun "they" has been interpreted, used, and accepted over time. We discuss trends in the findings and make suggestions for future research directions, including the need for better methods to investigate pronouns and clarification on what the focus of neutral language should be. This timely commentary has implications for action on equality, diversity, and inclusion. [ABSTRACT FROM AUTHOR]
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- 2024
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16. An Archaeometric Analysis of Black-Appearing Iron Age Glass Beads from Vinha das Caliças 4 (Portugal).
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Lončarić, Valentina, Arruda, Ana Margarida, Barrulas, Pedro, and Costa, Mafalda
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GLASS beads ,BEADS ,IRON Age ,TRACE element analysis - Abstract
Phoenician colonisation of the Iberian Peninsula in the 1st millennium BCE introduced many novel and luxurious goods to the local populations of the Western Mediterranean. Among them, black-appearing glass beads are characteristic of indigenous female burials in Southern Portugal during the 6th century BCE. This study presents the results of the first comprehensive archaeometric investigation of black-appearing glass from Vinha das Caliças 4 (Portugal), and of black-appearing glass from the Iberian Peninsula in general. A multi-analytical approach employing Stereomicroscopic observation of manufacture and use traces, VP-SEM-EDS, μ-XRD, and LA-ICP-MS was used to cover a wide range of questions regarding technology and provenance. All analysed samples are natron glass. All samples of black and white beads are characterized by high Zr and low Sr values typically ascribed to the use of Egyptian sands. A comparison of the results of previous studies from the same site clearly demonstrates at least two geochemical provenances for Phoenician-traded glass beads, located in the Levantine region and Egypt, respectively. Furthermore, different colours of glass in individual polychrome beads exhibit similar trace element patterns, which might suggest these beads could have been produced close to glassmaking sites/regions. [ABSTRACT FROM AUTHOR]
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- 2024
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17. A novel gradated zirconia implant material embedding bioactive ceramics: Osteoblast behavior and physicochemical assessment
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Peñarrieta-Juanito, Gabriella, Cruz, Mariana, Costa, Mafalda, Miranda, Georgina, Marques, Joana, Magini, Ricardo, Mata, António, Souza, Júlio C.M., Caramês, João, and Silva, Filipe S.
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- 2018
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18. Comparison of the performance of two handheld XRF instruments in the study of Roman tesserae from Cástulo (Linares, Spain)
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Costa, Mafalda, Rousaki, Anastasia, Lycke, Sylvia, Saelens, Delphine, Tack, Pieter, Sánchez, Alberto, Tuñón, José, Ceprián, Bautista, Amate, Pilar, Montejo, Manuel, Mirão, José, and Vandenabeele, Peter
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- 2020
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19. Lithic economy and territory of Epipaleolithic hunter–gatherers in the Middle Tagus: The case of Pena d'Água (Portugal)
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Pereira, Telmo, Andrade, Catarina, Costa, Mafalda, Farias, Anne, Mirão, José, and Carvalho, António Faustino
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- 2016
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20. Chemical Composition of Hydrophobic Coating Solutions and Its Impact on Carbonate Stones Protection and Preservation.
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Armal, Forough, Dias, Luís, Mirão, José, Pires, Vera, Sitzia, Fabio, Martins, Sérgio, Costa, Mafalda, and Barrulas, Pedro
- Abstract
The decay diagnosis and conservation of stone-built heritage is becoming a worldwide concern, especially when stone decay causes chromatic changes in the original stone aesthetics, which directly impacts its sociocultural value. Among all the causes of stone decay, water action is identified as the major cause of stone decay and chromatic changes in stone building materials; hence, protective eco-friendly hydrophobic coatings are the efficient and fundamental options to prevent penetrating water into the stone. This paper aims to contribute to tackling water action on natural building stones by studying three different commercial hydrophobic coatings and finding out the correlation between the effectivity, compatibility, and durability of these coatings and the physical, chemical, and mineralogical features of four distinct types of limestone, one calcitic dolomite, four kinds of marble, and one granitoid. Nine different natural stones have been chosen due to their variations in physical, chemical, and mineralogical natures. A multi-analytical approach was adopted through digital microscopy and colourimetry assays to assess the compatibility of the hydrophobic coatings, accelerating ageing in climatic chambers to assess their durability, optical tensiometer analyses to evaluate the hydrophobic effectiveness, and h-XRF and XRPD for determining the chemical and mineralogical composition of stone samples. The results obtained demonstrate that the coating composed of silane/siloxane with modified fluorinated additives (FAKOLITH FK-3 Plus Nano) is the most effective, compatible, and durable coating among the selected hydrophobic coatings. These results can be considered the pioneering steps for developing eco-friendly and cost-effective coatings. [ABSTRACT FROM AUTHOR]
- Published
- 2023
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21. Unveiling the Effectiveness of Innovative Commercial Coatings Used for the Preservation of Natural Stone—A Contribution.
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Dias, Luís, Nunes, Ricardo, Costa, Mafalda, Caldeira, Ana Teresa, Mirão, José, and Barrulas, Pedro
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STONE ,SILOXANE derivatives ,SURFACE coatings ,DETERIORATION of materials ,SURFACE potential - Abstract
The preservation of natural stone heritage is still a major challenge for the scientific community. This topic assumes a greater importance since it impacts economic and socio-cultural values. Recent research has indicated that water action and microorganism activity are among the major contributors to the deterioration of this material. Despite the emergence of new protective solutions in the market, some constraints still need to be overcome. This study aims to contribute to unveiling the effectiveness of innovative commercial coatings on the preservation of natural stone frequently used in built heritage. Four different commercial coatings are assessed regarding their compatibility with the substrata and effectiveness against UV radiation, water action, and microbial development under accelerated ageing. The protective solutions are tested on five different Portuguese lithotypes, including carbonate and silicate-based stones. Colour change is measured to assess compatibility, while profilometric change of the stones' surface and antimicrobial potential are evaluated to determine their effectiveness. Our research demonstrates that the solution that exhibits the greatest compatibility and effectiveness potential is composed of modified silanes and siloxanes derivatives. [ABSTRACT FROM AUTHOR]
- Published
- 2023
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22. AN INSIGHT INTO THE GREEN DETERIORATED PAINT LAYERS OF THE MARITIME STATION OF ALCÂNTARA (LISBON): AN ARCHEOMETRIC STUDY.
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ACEVEDO-MEJIA, Andrea, COSTA, Mafalda, VANDENABEELE, Peter, DIAS, Luís, FRADE, José C., and GIL, Milene
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MICROSCOPY ,PALETTE (Color range) ,MURAL art ,X-ray fluorescence ,PAINTING techniques ,CALCIUM sulfate - Abstract
This study reports the first results of the analysis carried out in 2022 on deteriorated green paint layers from the mural paintings made by Almada Negreiros at the Maritime Station of Alcantara, in Lisbon (Portugal). These murals painted in 1945 are one of the most emblematic painting sets done by the modernist artist and exhibit a bright chromatic palette that displays different states of conservation, with the green paint layers particularly damaged, showing severe flaking and powdering in the lightest shades. To understand the decay phenomenon, in-situ and laboratory analyses were done in an attempt to identify the green chromophores, the painting technique, and the decay agents causing the visible degradation. The analytical setup comprised in-situ technical photography (Vis, Vis-Rak, and UVF), handheld optical microscopy (h-OM), handheld energy dispersive X-ray fluorescence (h-EDXRF), colorimetry, and spectrophotometry in the visible light range. Microsamples of selected paint layers from deteriorated and stable green areas were collected and further analysed in the laboratory by optical microscopy in visible and ultraviolet modes (OM-UV-Vis), variable pressure scanning electron microscopy coupled with energy dispersive spectrometry (VP-SEM-EDS), micro-X-ray diffraction (μ-XRD), micro-Fourier-transform infrared spectroscopy (μ-FT-IR) and micro-Raman spectroscopy. Results show the presence of both natural and industrial synthetic organic pigments, such as green earths and PG8, used alone or in mixtures with other chromophores (e.g., Fe-based yellow and red pigments, bone and carbon black, ultramarine blue, and the synthetic green PG1 and the yellow PY1). Concerning the decay phenomena, the main hypothesis for the powdering and flaking of the green paint layers is the activity of calcium sulphates (e.g., gypsum), which probably originated from both intrinsic and extrinsic sources and whose presence was found to be widespread in all the microsamples analyzed. [ABSTRACT FROM AUTHOR]
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- 2023
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23. Glucosylglycerate metabolism, bioversatility and mycobacterial survival
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Nunes-Costa, Daniela, Maranha, Ana, Costa, Mafalda, Alarico, Susana, and Empadinhas, Nuno
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- 2017
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24. Known Glass Compositions in Iron Age Europe—Current Synthesis and Emerging Questions.
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Lončarić, Valentina and Costa, Mafalda
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IRON Age , *GLASS , *RAW materials , *TWENTIETH century , *GLASS industry , *CHEMICAL plants - Abstract
Ancient glass has been extensively studied from a technological and raw material provenance perspective since the middle of the 20th century. With the rising applications of analytical techniques in the field of Heritage Studies, the last two decades saw an exponential increase in publications on ancient and historical glass technology from around the globe. Given the amount of works on glass chemical composition, it is surprising to note that the long-held production model for Iron Age glasses found in Europe has only recently been challenged by the publication of uncharacteristic glass compositions. Traditionally, LBA glass industries based on plant-ash fluxes/HMG (Egypt and the Levant) and mixed-alkali fluxes/LMHK (Italy) are thought to be supplanted by natron-fluxed/LMG production operating in Egypt and the Levant since around the 9th century BCE. Recently, however, arguments have been put forth for a more diversified network of glassmaking traditions, including small-scale autonomous European workshops. This article reviews the current state of research into Iron Age (1st millennium BCE) glasses in Europe by examining the available published data on glass compositions to critically assess some practical and theoretical issues stemming from this heterogenous field of research. Key questions are addressed, and future lanes of research are proposed. [ABSTRACT FROM AUTHOR]
- Published
- 2023
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25. Hard and Soft Tissue Cell Behavior on Polyetheretherketone, Zirconia, and Titanium Implant Materials.
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da Cruz, Mariana Brito, Marques, Joana Faria, Peñarrieta-Juanito, Gabriella M., Costa, Mafalda, Souza, Júlio C. M., Magini, Ricardo S., Miranda, Georgina, Silva, Filipe Samuel, Pereira da Mata, António Duarte Sola, and Caramês, João Manuel Mendez
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FIBROBLASTS ,POLYMER analysis ,GINGIVA ,ANALYSIS of heavy metals ,OSTEOBLASTS ,CELL proliferation ,ALKALINE phosphatase ,ANALYSIS of variance ,BONE growth ,CELL culture ,CONTROLLED release drugs ,MATERIALS testing ,MICROSCOPY ,SCANNING electron microscopy ,STATISTICS ,TITANIUM ,DATA analysis ,DATA analysis software ,CELL survival ,FLUORESCENT dyes ,PHYSIOLOGY - Abstract
Purpose: The aim of this study was to characterize and compare the behavior of human osteoblasts and human gingival fibroblasts in contact with polyetheretherketone (PEEK), zirconia, and titanium implant surface materials. Materials and Methods: PEEK, yttria-stabilized zirconia (YTZP), and titanium disks were produced under appropriate and similar conditions to achieve controlled surface features. Human osteoblasts and human gingival fibroblasts were cultured on disks for 14 days. Cell viability and proliferation were evaluated using a resazurin-based method. Morphology and cellular adhesion were observed using field emission gun-scanning electron microscopy (FEG-SEM). Alkaline phosphatase (ALP) activity and bone cell mineralization was evaluated on osteoblasts. Confocal laser scanning microscopy (CLSM) images of fluorescent-stained fibroblasts were obtained at 7 and 14 days of the culture. Results were presented as mean and standard deviation (SD). Group comparisons were tested using analysis of variance (ANOVA) (Tukey's post hoc) with appropriate statistical software, and significance was set at P < .05. Results: Cell viability and proliferation were higher in PEEK and YTZP groups compared with titanium on osteoblast cells (P < .05, all time points) and on fibroblasts (P < .05, 7 and 14 days). All groups showed an increase in ALP activity over time, which was not significant. Mineralization patterns demonstrated an increase in mineral content over time, which was more apparent in the YTZP group. Cell spreading was more evident on PEEK and YTZP specimens. Conclusion: The results suggest increased adhesion, viability, and proliferation of osteoblasts and gingival fibroblasts on zirconia and PEEK surfaces compared with titanium. These results are correlated with the increased wettability of these materials. [ABSTRACT FROM AUTHOR]
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- 2019
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26. Trace Element Geochemistry of Alluvial TiO 2 Polymorphs as a Proxy for Sn and W Deposits.
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Gaspar, Miguel, Grácio, Nuno, Salgueiro, Rute, and Costa, Mafalda
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GEOCHEMISTRY ,TRACE elements ,TITANIUM dioxide ,TIN ,BEDROCK ,HYDROTHERMAL alteration - Abstract
The Segura mining field, the easternmost segment of the Góis–Panasqueira–Segura tin–tungsten metallogenic belt (north–central Portugal), includes Sn-W quartz veins and Li-Sn aplite-pegmatites, which are believed to be genetically related to Variscan Granites. Sediment geochemistry indicates granite-related Ti-enrichments, locally disturbed by mineralization, suggesting magmatic and metamorphic/metasomatic titaniferous phases. Therefore, Segura alluvial samples and the geochemistry of their TiO
2 polymorphs (rutile, anatase, and brookite) were investigated, and their potential as exploration tools for Sn and W deposits was evaluated. The heavy-mineral assemblages proved to be good proxies for bedrock geology, and TiO2 polymorph abundances were found to be suitable indicators of magmatic and/or metasomatic hydrothermal processes. The trace element geochemistry of Segura's alluvial rutile, anatase, and brookite is highly variable, implying multiple sources and a diversity of mineral-forming processes. The main compositional differences between TiO2 polymorphs are related to intrinsic (structural) factors, and to the P-T-X extrinsic parameters of their forming environments. Anomalous enrichments, up to 9% Nb, 6% Sn and W, 3% Fe, 2% Ta, and 1% V in rutile, and up to 1.8% Fe, 1.7% Ta, 1.2% Nb, 1.1% W 0.5% Sn and V in anatase, were registered. Brookite usually has low trace element content (<0.5%), except for Fe (~1%). HFSE-rich and granitophile-rich rutile is most likely magmatic, forming in extremely differentiated melts, with Sn and W contents enabling the discrimination between Sn-dominant and W-dominant systems. Trace element geochemical distribution maps show pronounced negative Sn (rutile+anatase) and W (rutile) anomalies linked to hydrothermal cassiterite precipitation, as opposed to their hydrothermal alteration halos and to W-dominant cassiterite-free mineralized areas, where primary hydrothermal rutile shows enrichments similar to magmatic rutile. This contribution recognizes that trace element geochemistry of alluvial TiO2 polymorphs can be a robust, cost- and time-effective, exploration tool for Sn(W) and W(Sn) ore deposit systems. [ABSTRACT FROM AUTHOR]- Published
- 2022
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27. A panel of microsatellite markers for genetic studies of European polecats (Mustela putorius) and ferrets (Mustela furo)
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Costa, Mafalda, Fernandes, Carlos, Rodrigues, Mónica, Santos-Reis, Margarida, and Bruford, Michael W.
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- 2012
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28. The chemistry behind the body art: unveiling the elemental profile and heavy metal content of natural tattoos and dyes by ICP-MS.
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Rubio, Laura, Barrulas, Pedro, Costa, Mafalda, Garcia-Jares, Carmen, Lores, Marta, and Barrocas Dias, Cristina
- Published
- 2022
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29. Osseointegration Assessment of Multi‐Material Ti6Al4V‐β TCP Implants: An Experimental Study in Rats.
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Costa, Mafalda M., Miranda, Alice, Bartolomeu, Flávio, Carvalho, Óscar, Matos, Sérgio, Silva, Filipe Samuel, and Miranda, Georgina
- Abstract
In the present study, mono‐ and multi‐material laser textured Ti6Al4V implants are manufactured and characterized in vivo to explore their applicability in orthopedic implants. Laser surface texturing is used for manufacturing grooved Ti6Al4V implants while a pressure‐assisted sintering technique is employed to impregnate beta‐tricalcium phosphate into grooves for an improved bioactivity. After implantation into Sprague Dawley rat's femur for 4 and 12 weeks, bone‐implant fixation and osseointegration are assessed, by performing push‐out tests and histological characterization. Histological characterization showed bone formation around all implants, characterized by immature bone at 4 weeks of implantation and a more mature bone after 12 weeks. The maximum push‐out forces are higher for the textured and multi‐material solution, when compared to non‐textured implants right after 4 weeks of implantation (p < 0.05). After 12 weeks, multi‐material implant displayed higher fracture energy when compared to non‐textured implants (p < 0.05). Results revealed that laser surface texturing and bioactive multi‐material solutions are highly effective to promote bone regeneration and enhance bone‐implant fixation for further application in orthopedic implants. [ABSTRACT FROM AUTHOR]
- Published
- 2022
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30. Mycobacterium hassiacum recovers from nitrogen starvation with up-regulation of a novel glucosylglycerate hydrolase and depletion of the accumulated glucosylglycerate
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Alarico, Susana, Costa, Mafalda, Sousa, Marta S., Maranha, Ana, Lourenço, Eva C., Faria, Tiago Q., Ventura, M. Rita, and Empadinhas, Nuno
- Published
- 2014
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31. Lithic arrowheads: Siliceous raw material sources and technology in Southern Portugal.
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Costa, Mafalda, Dias, Luís, Rocha, Leonor, Oliveira, Jorge, Barrulas, Pedro, and Mirão, José
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LASER ablation inductively coupled plasma mass spectrometry , *X-ray fluorescence , *RAW materials , *ARROWHEADS - Abstract
This analysis focused on one hundred and fifteen lithic arrowheads recovered from the Zambujeiro and Mitra 2 dolmens, funerary monuments in Évora, Portugal. These were analyzed by noninvasive and minimally invasive analytical techniques, including handheld X‐ray fluorescence (hXRF), variable pressure scanning electron microscope coupled with energy dispersive X‐ray spectrometry (VP‐SEM‐EDS), and laser ablation inductively coupled plasma mass spectrometry (LA‐ICP‐MS) to establish the sources of the raw materials used to manufacture these arrowheads and to compare and cluster different artefacts. The raw materials used in the manufacture of the arrowheads were found to be from different sources suggesting that long‐distance trade routes extending south, east and possibly west were in place in Southern Iberia during the Neolithic and Chalcolithic periods. Whether this difference is related to the availability of raw materials throughout time, different procurement strategies, or simply by choice, remains unknown. The trade routes associated with the Mitra 2 Dolmen also seem to have a greater range than those connected to the Zambujeiro Dolmen. [ABSTRACT FROM AUTHOR]
- Published
- 2022
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32. Millets and Cereal Meals from the Early Iron Age Underwater Settlement of "Gran Carro" (Bolsena Lake, Central Italy).
- Author
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Fundurulic, Ana, Valenti, Ilenia, Celant, Alessandra, Barbaro, Barbara, Costa, Mafalda, Manhita, Ana, Severi, Egidio, Barrocas Dias, Cristina, and Magri, Donatella
- Abstract
Archeobotanical materials recovered from pottery vessels originating from the underwater archeological site of "Gran Carro", located in Central Italy on the shore of Bolsena Lake, were analyzed to obtain new insight into the agricultural habits present in this Iron Age settlement. The archeobotanical study of cereal remains was combined with analytical data obtained from an amorphous organic residue using optical microscopy, SEM-EDS, ATR/FT-IR and Py-GC/MS. The cereal remains of emmer wheat (Triticum dicoccum), barley (Hordeum vulgare), broomcorn millet (Panicum miliaceum), and foxtail millet (Setaria italica) were identified as the preferred crops used for food and/or fodder at the site. The presence of charred millets, which have been directly dated by AMS, confirms consumption at the site and adds to the little-known background of millet use in central Italy. The find of millets in a perilacustrine pile-dwelling during a period when the water level of the Bolsena Lake was several meters lower than at present, attesting to a general dry period, suggests that the cultivation of millets, complementing more productive crops of wheat and barley, may have been favored by the availability of a large seasonally dry coastal plain, characterized by poor and sandy soils unsuitable for more demanding cereals. [ABSTRACT FROM AUTHOR]
- Published
- 2022
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33. Contribution of cereals and cows' milk consumption to the exposure to mycotoxins: a study with Portuguese children.
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Taborda, Bárbara, Santos, AP Marreilha, Costa, Mafalda T., Mendes, Maria Manuel, Lopes de Andrade, Vanda, and Mateus, Luisa
- Subjects
MYCOTOXINS ,FUSARIUM toxins ,MILK consumption ,PORTUGUESE people ,FOOD contamination ,FOOD consumption ,AFLATOXINS ,COWS - Abstract
The ubiquitous occurrence of mycotoxins in the environment results in unavoidable and repeated human exposure to mixtures of mycotoxins, the main exposure being through the consumption of contaminated foods, such as cereals and milk. Considering the frequency of contamination of these foods with mycotoxins, this study aimed to evaluate the risk of exposure to aflatoxins, ochratoxin A, deoxynivalenol and zearalenone in a Portuguese population under 17 years old through the consumption of these foods. To assess mycotoxin exposure, food contamination data was provided by the Official National Plan to Control Food and the food consumption information from the National Food, Nutrition, and Physical Activity Survey of the Portuguese General Population (2015–2016); risk assessment calculations were performed through the Monte Carlo probabilistic method. In view of the results obtained for aflatoxins, ochratoxin A, deoxynivalenol and zearalenone, and considering the legislation in force, the levels observed were below the maximum levels. However, there was a risk in deoxynivalenol exposure for children from 0 to 9 years old (average and high consumers), and for high consumers from 10 to 17 years old. Given the potential adverse effects of these mycotoxins, their co-existence in the same foods and being a priority issue defined by the European Food Safety Authority, tight control should be carried out, in addition to re-evaluation of the maximum levels of these mycotoxins. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
34. On the Two Working Palettes of Almada Negreiros at DN Building in Lisbon (1939–1940): First Analytical Approach and Insight on the Use of Cd Based Pigments.
- Author
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Gil, Milene, Costa, Mafalda, Cardoso, Ana, Valadas, Sara, Helvaci, Yigit, Bhattacharya, Sriradha, Moita, Patricia, and Candeias, Antonio
- Subjects
- *
PAINTING techniques , *SPECTROPHOTOMETRY , *BINDING mediums (Paint) , *MURAL art , *HISTORIOGRAPHY of art , *ART conservation & restoration - Abstract
This paper reports the first analytical approach carried out on two working palettes by Portuguese modernist master Almada Negreiros, found in 1991 behind old wood cabinets at the DN building in Lisbon. This is the only known occasion Almada left behind the color experiments done before starting to paint in the nearby walls and as such, it is a unique opportunity to analyze the materials and painting techniques that were originally used. The analytical setup comprised in loco technical photography in Vis, UVF and NIR; p-OM, spectrophotometry in Vis and h-EDXRF, complemented by OM-Vis, µ-FT-IR and VP-SEM-EDS of painting micro-samples and pigments in powder form. Preliminary results suggested the use of fresco painting technique and revealed some technical details, such as the use of a coarse lime sand finishing mortar mixed with natural vegetable fibers, and the extensive use of cadmium-based pigments that were not commonly used (or even recommended) in an alkaline environment. The Cd pigments were used alone or in mixtures with Fe based pigments in the warm hues and with cobalt and ultramarine blue pigments in some green paint layers. No clear evidence of organic materials that could have been used as binders was detected. [ABSTRACT FROM AUTHOR]
- Published
- 2021
- Full Text
- View/download PDF
35. Bioactive-Enhanced Polyetheretherketone Dental Implant Materials: Mechanical Characterization and Cellular Responses.
- Author
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da Cruz, Mariana Brito, Marques, Joana Faria, Peñarrieta-Juanito, Gabriella M., Costa, Mafalda, Souza, Júlio C. M., Magini, Ricardo S., Miranda, Georgina, Silva, Filipe Samuel, Caramês, João Manuel Mendez, and da Mata, António Duarte Sola Pereira
- Abstract
The aim of this study was to characterize the mechanical properties of a bioactive-modified polyetheretherketone (PEEK) manufacturing approach for dental implants and to compare the in vitro biological behavior with titanium alloy (Ti6Al4V) as the reference. PEEK, PEEK with 5% hydroxyapatite (HA), PEEK with 5% beta-tricalcium phosphate (βTCP), and Ti6Al4V discs were produced using hot pressing technology to create a functionally graded material (FGM). Surface roughness values (Ra, Rz), water contact angle, shear bond strength, and Vickers hardness tests were performed. Human osteoblasts and gingival fibroblasts bioactivity was evaluated by a resazurin-based method, alkaline phosphatase activity (ALP), and confocal laser scanning microscopy (CLSM) images of fluorescent-stained fibroblasts. Morphology and cellular adhesion were confirmed using field emission gun-scanning electron microscopy (FEG-SEM). Group comparisons were tested using analysis of variance (Tukey post hoc test), α =.05. All groups presented similar roughness values (P >.05). Ti6Al4V group was found to have the highest contact angle (P <.05). Shear bond strength and Vickers hardness of different PEEK materials were similar (P >.05); however, the mean values in the Ti6Al4V group were significantly higher when compared with those of the other groups (P <.05). Cell viability and proliferation of osteoblast and fibroblast cells were higher in the PEEK group (P <.05). PEEK-βTCP showed the highest significant ALP activity over time (P <.05 at 14 days of culture). An enhanced bone and soft-tissue cell behavior on pure PEEK was obtained to the gold standard (Ti6Al4V) with equivalent roughness. The results substantiate the potential role of chemical composition rather than physical properties of materials in biological responses. The addition of 5% HA or βTCP by FGM did not enhance PEEK mechanical properties or periodontal cell behavior. [ABSTRACT FROM AUTHOR]
- Published
- 2021
- Full Text
- View/download PDF
36. A comparative mobile Raman study for the on field analysis of the Mosaico de los Amores of the Cástulo Archaeological Site (Linares, Spain).
- Author
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Rousaki, Anastasia, Costa, Mafalda, Saelens, Delphine, Lycke, Sylvia, Sánchez, Alberto, Tuñón, José, Ceprián, Bautista, Amate, Pilar, Montejo, Manuel, Mirão, José, and Vandenabeele, Peter
- Subjects
- *
ARCHAEOLOGICAL excavations , *MEASURING instruments , *RAMAN lasers , *AUTOANALYZERS , *SPECTROMETERS - Abstract
An in situ archaeometrical campaign was organized in 2018 for the physicochemical analysis of the exceptional Mosaico de los Amores of the Cástulo archaeological site (Linares, Spain). Several mobile instruments were brought on the field to investigate the colourful tesserae of the mosaic. The main aim of the current research paper is the comparison of different mobile instruments and their applicability on measuring in open air environments. In this study, the comparison of four mobile Raman instruments, using different excitation lasers and technologies, is discussed. Three portable, the EZRaman‐I dual Raman analyser from TSI Inc. (USA), the i‐Raman® EX from BWTEK (USA), and the BWS445‐785S InnoRam™ Raman spectrometer from BWTEK (USA), and one handheld system, the Bravo Raman spectrometer from Bruker (Europe), are compared in terms of their characteristics, applicability, and performance when conducting non‐invasive and non‐destructive analysis. [ABSTRACT FROM AUTHOR]
- Published
- 2020
- Full Text
- View/download PDF
37. EXPLORATORY ANALYTICAL STUDY OF A 20TH CENTURY PORTUGUESE MURAL PAINTING BY JULIO RESENDE (1917-2011).
- Author
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KOVALEV, Ilia, COSTA, Mafalda, VALADAS, Sara, CARDOSO, Ana, CANDEIAS, António, and GIL, Milene
- Subjects
MURAL art ,ULTRAVIOLET spectrophotometry ,X-ray fluorescence ,ENERGY dispersive X-ray spectroscopy ,MICROSCOPY ,TWENTIETH century ,INFRARED spectroscopy - Abstract
This paper unveils for the first time the technical and material features of the mural painting entitled Pentecost's, executed by the Portuguese artist Julio Resende in 1955. The painting depicting twelve Apostles covers the altarpiece of a small church in the countryside of Évora (southern Portugal) and it was rediscovered in 2013 by art historians. The research was carried out with both non-invasive and micro-destructive techniques. In situ examination included technical photography in visible (Vis/Vis-RAK) and in infrared (NIR) light range, ultraviolet induced visible fluorescence (UVF), portable optical microscopy, visible spectrophotometry and handheld energy dispersive X-ray fluorescence spectroscopy (hXRF). Further analysis on paint layers micro-samples were undertaken by dark field optical microscopy (OM), scanning electron microscopy coupled with energy dispersive X-ray spectrometry (SEM-EDS) and micro-Fourier transform infrared spectroscopy (µ-FTIR). According to the acquired data, the mural was executed in a fresco technique (true and most likely lime fresco). Full size cartoons and handmade sketches were used for transferring the composition to the wall. No traces of organic binder were found with the analytical setup and the analysis of paint layers revealed the use of cobalt blue, a wide range of ochres, chromium green, green earth and barium white. The use of chrome orange and cadmium-based pigments are hypothesized. [ABSTRACT FROM AUTHOR]
- Published
- 2020
38. Infection of human keratinocytes by Streptococcus dysgalactiae subspecies dysgalactiae isolated from milk of the bovine udder
- Author
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Roma-Rodrigues, Catarina, Alves-Barroco, Cynthia, Raposo, Luís R., Costa, Mafalda N., Fortunato, Elvira, Baptista, Pedro Viana, Fernandes, Alexandra R., and Santos-Sanches, Ilda
- Published
- 2016
- Full Text
- View/download PDF
39. The combined use of Raman and micro‐X‐ray diffraction analysis in the study of archaeological glass beads.
- Author
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Costa, Mafalda, Arruda, Ana Margarida, Dias, Luís, Barbosa, Rui, Mirão, José, and Vandenabeele, Peter
- Subjects
- *
GLASS beads , *X-ray diffraction , *COPPER ions , *CHROMOPHORES , *HEAT treatment - Abstract
This study proposes a new nondestructive methodology that combines micro‐Raman spectroscopy and micro‐X‐ray diffraction (μ‐XRD), complemented by variable pressure scanning electron microscopy coupled with energy dispersive X‐ray spectrometry, to determine the composition of glass artifacts and the manufacturing techniques employed in their production. The use of micro‐Raman spectroscopy revealed that most samples belong to the alkaline glass family. Chemical analysis also allowed the identification of the main colorants used in the manufacture of the glass beads in this study. Dark blue and turquoise glass were colored using cobalt ions and copper ions, respectively. Amber or light brown hues were produced using the iron–sulfur amber chromophore. Iron ions were also used to produce green, yellow, cream‐colored gray, and black hues. White glass was produced using calcium antimonate phases. These compounds, identified by micro‐Raman spectroscopy and μ‐XRD, were also used as opacifying agents. This study highlights the importance of using micro‐Raman spectroscopy in the study of ancient glass artifacts. In fact, micro‐Raman spectroscopy not only allows the determination of the glass family of heavily degraded samples but was also found to be the only technique capable of identifying evidences of the rearrangement of the silicate network following selective leaching. The combined use of micro‐Raman spectroscopy and μ‐XRD permitted the identification of the opacifying agents and heat treatment used in the manufacture of the opaque glass beads in this study. This study proposes a new nondestructive methodology that combines micro‐Raman spectroscopy and μ‐XRD to determine the composition and manufacturing techniques employed in the production of glass artifacts. Results show that micro‐Raman spectroscopy allows the determination of the glass family of heavily degraded samples and reveals evidences of the rearrangement of the silicate network following selective leaching. This methodology allowed the identification of the opacifiers and heat treatment used in the manufacture of the opaque glass beads in this study. [ABSTRACT FROM AUTHOR]
- Published
- 2019
- Full Text
- View/download PDF
40. A Micro-Analytical Study of the Scarabs of the Necropolis of Vinha das Caliças (Portugal).
- Author
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Costa, Mafalda, Arruda, Ana Margarida, Barbosa, Rui, Barrulas, Pedro, Vandenabeele, Peter, and Mirão, José
- Published
- 2019
- Full Text
- View/download PDF
41. Bioactivity of novel functionally structured titanium‐ceramic composites in contact with human osteoblasts.
- Author
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Peñarrieta‐Juanito, Gabriella M., Costa, Mafalda, Cruz, Mariana, Miranda, Georgina, Henriques, Bruno, Marques, Joana, Magini, Ricardo, Mata, Antonio, Caramês, João, Silva, Filipe, and Souza, Júlio C. M.
- Abstract
Abstract: The aim of this study was to analyze the osteogenic cell behavior on the surface of novel functionally graded titanium‐based composites containing bioactive ceramics. Titanium grade V discs (8 × 3 mm) embedding gradual content of hydroxyapatite (TiAlV‐HA) or beta‐tricalcium phosphate (TiAlV‐βTCP) were produced by hot‐pressing technique. Titanium‐ceramic composite discs and Ti grade V (control group) were placed in contact with human osteoblast culture assays. The morphology and adhesion of osteoblasts were inspected by field emission guns scanning electron microscopy (FEGSEM) while cell viability was assessed by fluorometric method. Alkaline phosphatase (ALP) activity and fluorescent microscopic analyses were used to evaluate mineralization on the test and control discs. FEGSEM images showed cells adhered to Ti6Al4V‐ceramic and Ti6Al4V surfaces over a period of 24 h, and therefore, an intense proliferation of osteoblasts and spreading cells was noticed for 7 days. Cell viability increased with time on all the surfaces although TiAlV‐βTCP revealed significant higher percentage of cell viability than that recorded for TiAlV‐HA (p < 0.01). TiAlV‐βTCP also showed the highest hydrophilic character. ALP levels increased on the Ti6Al4V‐ceramic surfaces when compared to the control group. Also, a qualitative analysis of mineralization evidenced an increase in mineral content on TiAlV‐HA or TiAlV‐βTCP groups. Novel functionally graded composites based on Ti grade V and hydroxyapatite or βTCP showed a higher bioactivity in presence of osteoblasts than that recorded on Ti grade V. Also, such functionally graded materials can prevent risks of failures by detachment of bioactive ceramic materials during implant placement. © 2018 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 106A: 1923–1931, 2018. [ABSTRACT FROM AUTHOR]
- Published
- 2018
- Full Text
- View/download PDF
42. Micro-Raman spectroscopy and complementary techniques (hXRF, VP-SEM-EDS, μ-FTIR and Py-GC/MS) applied to the study of beads from the Kongo Kingdom (Democratic Republic of the Congo).
- Author
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Coccato, Alessia, Costa, Mafalda, Rousaki, Anastasia, Clist, Bernard‐Olivier, Karklins, Karlis, Bostoen, Koen, Manhita, Ana, Cardoso, Ana, Barrocas Dias, Cristina, Candeias, António, Moens, Luc, Mirão, José, and Vandenabeele, Peter
- Subjects
- *
RAMAN spectroscopy , *FOURIER transform infrared spectroscopy , *GAS chromatography/Mass spectrometry (GC-MS) , *ARCHAEOLOGICAL excavations - Abstract
In the framework of the inter-disciplinary KongoKing project, a set of beads from archaeological excavations in the Democratic Republic of the Congo was analysed by means of a minimally invasive, multi-analytical approach based on micro-Raman spectroscopy. The full characterization of the materials, including glassy network, opacifiers and colorizers, was achieved thanks to the combination of data from handheld X-ray fluorescence, variable pressure scanning electron microscopy coupled with energy-dispersive X-ray spectrometry, micro-Fourier transform infrared spectroscopy and pyrolysis coupled to gas chromatography and mass spectrometry. The obtained chemical information was used to fill the existing gap in the chemical study of beads from Western Central Africa. The cobalt-rich blue beads were found to be of Central European origin, while the copper-rich turquoise beads were manufactured using distinct copper sources. Cadmium yellow and cadmium red are the colourants responsible for the bright colours of bead types 10 and 12, respectively. The type 12 beads were found to be composed of glass covered with a waxy layer tentatively identified as Japan wax. Prosser-moulded bead type 9 was coloured by means of a chrome-tin pigment, while a combination of Mn and Fe is responsible for the black colour of the type 47 beads. Cuprite is most likely responsible for the red hue of glass layers from type 14. The dark palm green exterior of the type 17 bead was produced by using a combination of Cu and Fe compounds; iron was the only chromophore detected in the Indian red decoration. Copyright © 2017 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]
- Published
- 2017
- Full Text
- View/download PDF
43. Prospects and challenges for the conservation of farm animal genomic resources, 2015-2025.
- Author
-
Bruford, Michael W., Ginja, Catarina, Hoffmann, Irene, Joost, Stéphane, Orozco-terWengel, Pablo, Alberto, Florian J., Amaral, Andreia J., Barbato, Mario, Biscarini, Filippo, Colli, Licia, Costa, Mafalda, Curik, Ino, Duruz, Solange, aković, Maja Ferenč, Fischer, Daniel, Fitak, Robert, Groeneveld, Linn F., Hall, Stephen J. G., Hanotte, Olivier, and Hassan, Faiz-ul
- Subjects
DOMESTIC animal genetics ,GERMPLASM conservation - Abstract
Livestock conservation practice is changing rapidly in light of policy developments, climate change and diversifying market demands. The last decade has seen a step change in technology and analytical approaches available to define, manage and conserve Farm Animal Genomic Resources (FAnGR). However, these rapid changes pose challenges for FAnGR conservation in terms of technological continuity, analytical capacity and integrative methodologies needed to fully exploit new, multidimensional data. The final conference of the ESF Genomic Resources program aimed to address these interdisciplinary problems in an attempt to contribute to the agenda for research and policy development directions during the coming decade. By 2020, according to the Convention on Biodiversity's Aichi Target 13, signatories should ensure that the genetic diversity of farmed and domesticated animals and of wild relatives is maintained, and strategies have been developed and implemented for minimizing genetic erosion and safeguarding their genetic diversity. However, the real extent of genetic erosion is very difficult to measure using current data. Therefore, this challenging target demands better coverage, understanding and utilization of genomic and environmental data, the development of optimized ways to integrate these data with social and other sciences and policy analysis to enable more flexible, evidence-based models to underpin FAnGR conservation. At the conference, we attempted to identify the most important problems for effective livestock genomic resource conservation during the next decade. Twenty priority questions were identified that could be broadly categorized into challenges related to methodology, analytical approaches, data management and conservation. It should be acknowledged here that while the focus of our meeting was predominantly around genetics, genomics and animal science, many of the practical challenges facing conservation of genomic resources are societal in origin and are predicated on the value (e.g., socio-economic and cultural) of these resources to farmers, rural communities and society as a whole. The overall conclusion is that despite the fact that the livestock sector has been relatively well-organized in the application of genetic methodologies to date, there is still a large gap between the current state-of-the-art in the use of tools to characterize genomic resources and its application to many non-commercial and local breeds, hampering the consistent utilization of genetic and genomic data as indicators of genetic erosion and diversity. The livestock genomic sector therefore needs to make a concerted effort in the coming decade to enable to the democratization of the powerful tools that are now at its disposal, and to ensure that they are applied in the context of breed conservation as well as development. [ABSTRACT FROM AUTHOR]
- Published
- 2015
- Full Text
- View/download PDF
44. Single nucleotide polymorphism detection using gold nanoprobes and bio-microfluidic platform with embedded microlenses.
- Author
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Bernacka‐Wojcik, Iwona, Águas, Hugo, Carlos, Fabio Ferreira, Lopes, Paulo, Wojcik, Pawel Jerzy, Costa, Mafalda Nascimento, Veigas, Bruno, Igreja, Rui, Fortunato, Elvira, Baptista, Pedro Viana, and Martins, Rodrigo
- Abstract
ABSTRACT The use of microfluidics platforms combined with the optimal optical properties of gold nanoparticles has found plenty of application in molecular biosensing. This paper describes a bio-microfluidic 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/µL below the limit of detection of the conventionally used microplate reader (i.e., 15 ng/µL) with 10 times lower solution volume (i.e., 3 µL). A set of optimization of our previously reported bio-microfluidic platform (Bernacka-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 nanoparticles, 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' colorimetric changes and also the LEDs transmission spectra when illuminating through various solutions. Furthermore, by coupling an optical microscope to a digital camera with a long exposure time (30 s), 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). Biotechnol. Bioeng. 2015;112: 1210-1219. © 2015 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]
- Published
- 2015
- Full Text
- View/download PDF
45. Strategies used by nurses and tracheostomized users in communication: systematic review.
- Author
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Patrão Duarte, Ana Rita Verissimo, Silva Patacas de Castro, Cidália Maria da Cruz, Mártires Nobre, Inês dos, Santos Cordeiro, Joana Mafalda dos, and da Costa, Mafalda Luís Pereira
- Subjects
MEDICAL personnel ,NURSES as patients ,NURSES ,LIPREADING ,NURSE-patient relationships ,HOSPITAL closures ,SPEECH therapists - Abstract
Communication is a basic human need necessary to establish a relationship of trust between patients and multidisciplinary team, especially with nursing team. With this, it is necessary to find strategies that allows not only the tracheostomized patients but also nurses to communicate in an effective way [1]. This is a systematic review that aims to give an answer to our investigation question: "Which strategies are used by nurses and tracheostomized patients in communication?" To understand which strategies are used by nurses and tracheostomized patients in communication. Our research was based on electronic data such as B-On, SciELO, RCAAP and EBSCOhost. According to our descriptors: communication, strategies, nursing and tracheostomy, we included articles published between 2011 and 2019, in Portuguese or English. Seven articles were included in this systematic review. From the analysis of the data emerged three fundamental themes regarding the strategies used by nurses and tracheostomized patients in communication, that are: (1) Communication strategies used; (2) Communication facilitators; (3) Difficulty in communication and social interaction. Regarding the first theme, we consider that the alternative communication strategies used by tracheostomized individuals involve gestures or writing, lip reading, illustrative cards, the speech valve and tracheostomy occlusion [2]. According to the second theme, we found that the user must be encouraged to speak clearly and slowly, taking into account key words or phrases (that may give clues) and to blink differently for yes or no [3]. Regarding the last theme, the difficulties shown by the tracheostomy user go through the inability to change the volume and tone of voice, thereby affecting social interaction with others [4]. The knowledge of health professionals regarding the stress factor of these users leads to a lack of expressiveness due to the inability to communicate. The communication of these two actors is considered a key element, helping to reassure the user [5]. For all these strategies, the positioning of the user and the receptor of the message is a primary factor [2]. The need for strategies to overcome the difficulties experienced by tracheostomized users provides a consistent basis for promotion quality nursing care [1,2]. The studies analysed indicate that currently, despite the existence of several communication techniques between the user and the other health professionals, (namely nurses), there is still some difficulty in teaching them. This difficulty has implications for the continuity of health care and affects not only users, but also their family and all professionals with whom they are in contact during hospitalisation. This review is important because it contributes to the improvement of nursing care and the compliance of the user. [ABSTRACT FROM AUTHOR]
- Published
- 2021
- Full Text
- View/download PDF
46. SELECTIVE GROWTH OF 1D NANOSTRUCTURED OXIDE MATERIALS USING PDMS STAMP.
- Author
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DANCIU, Anca-Ionela, MUSAT, Viorica, BUSANI, Tito, GONÇALVES, Alexandra, PINTO, Joana V., COSTA, Mafalda, BERNACKA-WOJCIK, Iwona, MARTINS, Rodrigo, and FORTUNATO, Elvira
- Abstract
The approach for selective growth of 1D nanostructured oxide materials using poly (dimethylsiloxane) (PDMS) stamp consists of using microcontact printing, as such the soft lithography technique, for transferring the pattern of ZnO film on a substrate, followed by the hydrothermal growth of 1D nanowires on patterned areas. The nanowires have been grown in aqueous solutions of zinc nitrate at temperature at 95°C. The wettability of the glass and of the Si/SiO
2 substrates was investigated by contact angle measurements. The morphology of the nanostructures obtained was characterized by optical microscopy and scanning electron micoscopy. [ABSTRACT FROM AUTHOR]- Published
- 2012
47. Characterization of Triacylglycerols in Madeira Laurel Oil by HPLC-Atmospheric Pressure Chemical Ionization-MS.
- Author
-
Castilho, Paula C., Do Céu Costa, Maria, Rodrigues, Ana, Costa Branco, Pedro, and Costa, Mafalda
- Subjects
LAUREL ,FATS & oils ,ATMOSPHERIC pressure ,MASS spectrometry ,LIPIDS - Abstract
Madeira laurel oil was fractionated by liquid extraction combined with TLC, and TAGs were analyzed by HPLC coupled with atmospheric pressure chemical ionization-MS (APCI-MS). Eluted molecular species compositions of the eluted TAG in the complex natural mixture were determined by GC identification of FAME and by LC-atmospheric pressure chemical ionization (APCI)-MS analysis of the lipid. The APCI-MS spectra of most TAG exhibited [M + H]
+ and [M - RCOO]+ ions, which defined the M.W. and the molecular association of fatty acyl residues, respectively. Despite the relatively high degree of saturation, with a saturated/unsaturated ratio of 0.70, no totally saturated TAG nor mixed asymmetric TAG with two saturated FA (SSM or SSU, where S is saturated, M is monounsaturated, and U is unsaturated) were found. This type of molecular structure provides a possible explanation for the relatively low m.p. (12-15°C) and also the high oxidative resistance observed. [ABSTRACT FROM AUTHOR]- Published
- 2004
- Full Text
- View/download PDF
48. Analysis of green pigments: The case of Almada Negreiros maritime station murals in Lisbon (Portugal)
- Author
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Valadas, Sara, Vandenabeele, Peter, Gil, Milene, Frade, José C., Vermeersch, Eva, Lycke, Sylvia, Dias, Luís, Candeias, António, and Costa, Mafalda
- Subjects
- *
PIGMENT analysis , *PIGMENTS , *TITANIUM dioxide , *X-ray fluorescence , *PAINTING techniques , *RAMAN spectroscopy - Abstract
In 1949, Almada Negreiros painted at the maritime station of Rocha do Conde de Óbidos, in Lisbon, six monumental mural paintings, which are considered as his highest artistic achievement. On these paintings, he resorted to a bright colourful palette, which needs to be studied to support conservation and preservation of these artworks for future generations. Among the pigments under study within project ALMADA, the identification of the green samples is the most challenging, as Almada Negreiros seems to have explored different hues by using simultaneously inorganic (e.g., emerald green, Scheele's green and viridian) as well as organo‐synthetic pigments that were rather unusual when employing a traditional mural painting technique (e.g., PG7 and PG8). Moreover, he seems to have admixed white (e.g., titanium white) or blue pigments (e.g., ultramarine) to modify the hues. The different colourants found, as well as the use of mixtures of pigments, hints that Almada Negreiros was keen on experimenting and applying relatively novel painting materials. Raman spectroscopy, given its ability to identify inorganic as well as organic components, is a key analytical tool to discriminate between all these compounds. The findings were also supported by complimentary analytical techniques, including colourimetry, handheld X‐ray fluorescence spectroscopy (h‐XRF) and micro‐Fourier‐transform infrared spectroscopy (μ‐FT‐IR). Identification of the green pigments by Raman spectroscopy is, however, not always straightforward, and it is demonstrated how changes in relative band intensities and band broadening can point to mixtures, where the Raman spectral features of some compounds can easily be overseen in the spectrum. [ABSTRACT FROM AUTHOR]
- Published
- 2024
- Full Text
- View/download PDF
49. Estimating public health and economic benefits along 10 years of Fluzone® High Dose in the United States.
- Author
-
Net, Pierre, Colrat, Florian, Nascimento Costa, Mafalda, Bianic, Florence, Thommes, Edward, and Alvarez, Fabián P.
- Subjects
- *
PUBLIC health , *VACCINE effectiveness , *COST control , *INFLUENZA vaccines , *INFLUENZA - Abstract
The objective of this study was to estimate the public health and economic benefits (from a Medicare perspective) of Fluzone High-Dose® in the US elderly population, since its introduction in 2010. A budget impact model was developed using a decision tree framework and applied over 9 influenza seasons (2010/11 to 2018/19). The decision tree model was designed to capture influenza cases, hospitalizations possibly related to influenza or laboratory confirmed influenza, and influenza-related deaths. The analysis included influenza vaccines recommended by ACIP since 2010: SD TIV (trivalent), SD QIV (quadrivalent), HD TIV, aTIV (adjuvanted), ccQIV (cell-cultured). Two strategies were compared to evaluate the impact of HD TIV: a 'with HD TIV' strategy representative of the US vaccine landscape, and a 'without HD TIV' where the absence of HD TIV was modelled. Clinical and economic inputs were based on public US data from the CDC and national databases, while data on vaccine effectiveness were extracted from published literature and clinical trials. The impact of HD TIV was further explored in five scenario analyses and deterministic sensitivity analyses (DSA). Over 10 years, it is estimated that HD TIV resulted in an averted 1,333,479 influenza cases, 769,476 medical visits, 40,004 ED presentations, 520,342 cardiorespiratory hospitalizations and 73,689 deaths and generated an absolute $4.6 billion in savings, translating into a return on investment of 214.4%. Hospitalizations costs represented 98.4% and 98.3% of the management costs in the 'with HD TIV' strategy and 'without HD TIV' strategy respectively. Hospitalizations and HD TIV relative vaccine efficacy vs SD TIV as a major cost driver were further confirmed in scenario analysis and DSA. HD TIV remained cost saving under all the scenarios. The model showed that HD TIV higher efficacy translated into increased averted health and economic outcomes. HD TIV represented a cost saving intervention from a payer perspective since its introduction. [ABSTRACT FROM AUTHOR]
- Published
- 2021
- Full Text
- View/download PDF
50. Human osteoblast and fibroblast behavior on modified zirconia implant surfaces.
- Author
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Cruz, Mariana, Marques, Joana, Peñarrieta‐Juanito, Gabriella, Silva, Filipe, Mata, António, Costa, Mafalda, Miranda, Georgina, Souza, Júlio, Magini, Ricardo, Mario Meloni, Silvio, and Caramês, João
- Subjects
OSTEOBLASTS ,DENTAL implants ,FIBROBLASTS - Abstract
Background: Zirconia dental implants have been proposed as an option for oral rehabilitation. Hydroxyapatite and calcium phosphate based coatings have been described to improve the bioactivity of zirconia, however, there is a need for alternate solutions since these coatings may delaminate. Aim/Hypothesis: The aim of this study was to compare the in vitro response of human fetal osteoblasts and human gingival fibroblasts in contact with Zirconia based implant surfaces‐ Zirconia (control), Zirconia containing hydroxyapatite (ZrHA) or beta tricalcium phosphate (ZrTCP). Material and Methods: Zirconia discs (control, 5% HA or 5% TCP) were produced by a novel pressing‐sintering technique under appropriate and similar conditions to achieve controlled surfaces. Human osteoblasts and gingival fibroblasts were cultured for 15 days by previously described methods. Morphology and cellular adhesion were observed using scanning electron microscopy (SEM) after 1 and 7 days. Cell viability and proliferation were evaluated at pre‐defined time‐points (1, 3, 7 and 14 days) using a commercial resazurin‐based method. Alkaline phosphatase (ALP) activity of human osteoblasts was evaluated at 7 and 14 days. All results were presented as mean fluorescence intensity (AU) ± standard deviation (SD). Group comparisons were tested using Anova (Tukey's post‐hoc) using appropriate statistical software and significance was set _I_P_i_ < 0.05. Results: SEM presented a good cell spreading in all groups on osteoblasts and fibroblasts. Cell viability and proliferation increased over time for all groups on the two types of cells, with osteoblasts viability being significantly higher on ZrHA group (211.32 ± 39.04 AUs) comparing to Zr (90.82 ± 29.95 AUs) and Zr‐TCP (125.51 ± 36.92 AUs) at 14 days of culture. However, when assessing fibroblast viability, the Zr group (249.98 ± 60.40 AUs, 595.98 ± 69.40 AUs) presented significantly higher values when compared to the remaining groups at 7 and 14 day culture, respectively. ALP results on osteoblasts suggested a higher activity in ZrHA group compared to the others at 7 and 14 days (_I_P_i_ < 0.05). Conclusions and Clinical Implications: All groups presented increasing cell viability and proliferation over time. Human osteoblasts presented higher viability, proliferation and differentiation on ZrHA surfaces when compared to Zr and Zr‐TCP. However, human gingival fibroblasts revealed an enhanced behavior on pure Zr surface compared to other groups. These results suggest different behaviors of representative cell models of bone and gingival connective tissue. Further in vitro studies are needed. [ABSTRACT FROM AUTHOR]
- Published
- 2018
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