Records |
Author |
Rossbach, L.M.; Brede, D.A.; Nuyts, G.; Cagno, S.; Olsson, R.M.S.; Oughton, D.H.; Falkenberg, G.; Janssens, K.; Lind, O.C. |
Title |
Synchrotron XRF analysis identifies cerium accumulation colocalized with pharyngeal deformities in CeO₂ NP-exposed caenorhabditis elegans |
Type |
A1 Journal article |
Year |
2022 |
Publication |
Environmental science and technology |
Abbreviated Journal |
Environ Sci Technol |
Volume |
56 |
Issue |
8 |
Pages |
5081-5089 |
Keywords |
A1 Journal article; Antwerp X-ray Imaging and Spectroscopy (AXIS) |
Abstract |
A combination of synchrotron radiation-based elementalimaging, in vivo redox status analysis, histology, and toxic responses was usedto investigate the uptake, biodistribution, and adverse effects of Cenanoparticles (CeO2NP; 10 nm; 0.5-34.96 mg Ce L-1) or Ce(NO3)3(2.3-26 mg Ce L-1)inCaenorhabditis elegans. Elemental mapping of theexposed nematodes revealed Ce uptake in the alimentary canal prior todepuration. Retention of CeO2NPs was low compared to that of Ce(NO3)3in depurated individuals. X-rayfluorescence (XRF) mapping showed that Cetranslocation was confined to the pharyngeal valve and foregut. Ce(NO3)3exposure significantly decreased growth, fertility, and reproduction, causedslightly reduced fecundity. XRF mapping and histological analysis revealedsevere tissue deformities colocalized with retained Ce surrounding thepharyngeal valve. Both forms of Ce activated the sod-1 antioxidant defense,particularly in the pharynx, whereas no significant effects on the cellular redox balance were identified. The CeO2NP-induceddeformities did not appear to impair the pharyngeal function or feeding ability as growth effects were restricted to Ce(NO3)3exposure. The results demonstrate the utility of integrated submicron-resolution SR-based XRF elemental mapping of tissue-specificdistribution and adverse effect analysis to obtain robust toxicological evaluations of metal-containing contaminants. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000793137500039 |
Publication Date |
2022-04-04 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0013-936x; 1520-5851 |
ISBN ![sorted by ISBN field, descending order (down)](img/sort_desc.gif) |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
11.4 |
Times cited |
|
Open Access |
OpenAccess |
Notes |
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Approved |
Most recent IF: 11.4 |
Call Number |
UA @ admin @ c:irua:188662 |
Serial |
7216 |
Permanent link to this record |
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Author |
Byrnes, I.; Rossbach, L.M.; Jaroszewicz, J.; Grolimund, D.; Sanchez, D.F.; Gomez-Gonzalez, M.A.; Nuyts, G.; Reinoso-Maset, E.; Janssens, K.; Salbu, B.; Brede, D.A.; Lind, O.C. |
Title |
Synchrotron XRF and histological analyses identify damage to digestive tract of uranium NP-exposed Daphnia magna |
Type |
A1 Journal article |
Year |
2023 |
Publication |
Environmental science and technology |
Abbreviated Journal |
|
Volume |
57 |
Issue |
2 |
Pages |
1071-1079 |
Keywords |
A1 Journal article; Antwerp X-ray Imaging and Spectroscopy (AXIS) |
Abstract |
Micro-and nanoscopic X-ray techniques were used to investigate the relationship between uranium (U) tissue distributions and adverse effects to the digestive tract of aquatic model organism Daphnia magna following uranium nanoparticle (UNP) exposure. X-ray absorption computed tomography measure-ments of intact daphnids exposed to sublethal concentrations of UNPs or a U reference solution (URef) showed adverse morphological changes to the midgut and the hepatic ceca. Histological analyses of exposed organisms revealed a high proportion of abnormal and irregularly shaped intestinal epithelial cells. Disruption of the hepatic ceca and midgut epithelial tissues implied digestive functions and intestinal barriers were compro-mised. Synchrotron-based micro X-ray fluorescence (XRF) elemental mapping identified U co-localized with morphological changes, with substantial accumulation of U in the lumen as well as in the epithelial tissues. Utilizing high-resolution nano-XRF, 400-1000 nm sized U particulates could be identified throughout the midgut and within hepatic ceca cells, coinciding with tissue damages. The results highlight disruption of intestinal function as an important mode of action of acute U toxicity in D. magna and that midgut epithelial cells as well as the hepatic ceca are key target organs. |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000910915100001 |
Publication Date |
2023-01-04 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0013-936x; 1520-5851 |
ISBN ![sorted by ISBN field, descending order (down)](img/sort_desc.gif) |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
11.4 |
Times cited |
|
Open Access |
OpenAccess |
Notes |
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Approved |
Most recent IF: 11.4; 2023 IF: 6.198 |
Call Number |
UA @ admin @ c:irua:193478 |
Serial |
7342 |
Permanent link to this record |
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Author |
Monico, L.; Cotte, M.; Vanmeert, F.; Amidani, L.; Janssens, K.; Nuyts, G.; Garrevoet, J.; Falkenberg, G.; Glatzel, P.; Romani, A.; Miliani, C. |
Title |
Damages induced by synchrotron radiation-based X-ray microanalysis in chrome yellow paints and related Cr-compounds : assessment, quantification, and mitigation strategies |
Type |
A1 Journal article |
Year |
2020 |
Publication |
Analytical Chemistry |
Abbreviated Journal |
Anal Chem |
Volume |
92 |
Issue |
20 |
Pages |
14164-14173 |
Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
Abstract |
Synchrotron radiation (SR)-based X-ray methods are powerful analytical tools for several purposes. They are widely used to probe the degradation mechanisms of inorganic artists' pigments in paintings, including chrome yellows (PbCr1-xSxO4; 0 <= x <= 0.8), a class of compounds often found in Van Gogh masterpieces. However, the high intensity and brightness of SR beams raise important issues regarding the potential damage inflicted on the analyzed samples. A thorough knowledge of the SR X-ray sensitivity of each class of pigment in the painting matrix is therefore required to find analytical strategies that seek to minimize the damage for preserving the integrity of the analyzed samples and to avoid data misinterpretation. Here, we employ a combination of Cr K-edge X-ray absorption near-edge structure spectroscopy, Cr-K-beta X-ray emission spectroscopy, and X-ray diffraction to monitor and quantify the effects of SR X-rays on the stability of chrome yellows and related Cr compounds and to define mitigation strategies. We found that the SR X-ray beam exposure induces changes in the oxidation state and local coordination environment of Cr ions and leads to a loss of the compound's crystalline structure. The extent of X-ray damage depends on some intrinsic properties of the samples (chemical composition of the pigment and the presence/absence and nature of the binder). It can be minimized by optimizing the overall fluence/dose released to the samples and by working in vacuum and under cryogenic conditions. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000584418100072 |
Publication Date |
2020-09-21 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0003-2700; 5206-882x |
ISBN ![sorted by ISBN field, descending order (down)](img/sort_desc.gif) |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
7.4 |
Times cited |
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Open Access |
|
Notes |
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Approved |
Most recent IF: 7.4; 2020 IF: 6.32 |
Call Number |
UA @ admin @ c:irua:174363 |
Serial |
7754 |
Permanent link to this record |
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Author |
Beltran, V.; Marchetti, A.; De Meyer, S.; Nuyts, G.; De Wael, K. |
Title |
Geranium lake pigments : the role of the synthesis on the structure and composition |
Type |
A1 Journal article |
Year |
2021 |
Publication |
Dyes And Pigments |
Abbreviated Journal |
Dyes Pigments |
Volume |
189 |
Issue |
|
Pages |
109260 |
Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
Abstract |
Eosin Y has an extraordinary capacity to form complexes with metallic elements, that have applications in many different fields, from photovoltaics and photocatalysis to historical artists? pigments. To unravel the complexes reactivity, it is essential to have a precise knowledge of their structure and composition, as well as how these can be affected by the synthesis protocol, an often underestimated factor. This manuscript presents a thorough investigation of the structure and composition of eosin Y complexes based on Al and Pb, by FTIR, XRPD and Raman spectroscopy, with a particular focus on the effect of the synthesis conditions. Results clearly show the change of the coordination mode in Pb complexes depending on the protocol, while the structure of Al complexes remains stable. In both cases, the formation of by-products was observed. Additionally, a detailed band assignment of the FTIR and Raman spectra of eosin Y and Pb and Al complexes is described, providing interesting details such as the interaction between the metallic ion and the xanthene moiety (chromophore). This is extremely important for the analysis of historical paintings where eosin Y is bonded to metallic ions, as well as for other materials in dye-sensitized solar cells, wastewater treatment or photocatalysis. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000634733200001 |
Publication Date |
2021-03-03 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
|
Edition |
|
ISSN |
0143-7208 |
ISBN ![sorted by ISBN field, descending order (down)](img/sort_desc.gif) |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.473 |
Times cited |
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Open Access |
OpenAccess |
Notes |
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Approved |
Most recent IF: 3.473 |
Call Number |
UA @ admin @ c:irua:177676 |
Serial |
8002 |
Permanent link to this record |
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Author |
Cagno, S.; Lind, O.C.; Popic, J.M.; Skipperud, L.; De Nolf, W.; Nuyts, G.; Vanmeert, F.; Jaroszewicz, J.; Janssens, K.; Salbu, B. |
Title |
Micro-analytical characterization of thorium-rich aggregates from Norwegian NORM sites (Fen Complex, Telemark) |
Type |
A1 Journal article |
Year |
2020 |
Publication |
Journal Of Environmental Radioactivity |
Abbreviated Journal |
J Environ Radioactiv |
Volume |
219 |
Issue |
|
Pages |
106273 |
Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
Abstract |
In this study we performed microscopic characterization of mineral particles that were collected in the thorium-rich Fen Complex in Norway and identified and isolated based on autoradiography in function of their radioactivity. For this we combined information obtained with X-ray absorption mu-CT, mu-XRF and mu-XRD, both in bi- and in three-dimensional (tomographic) mode. We demonstrate that radionuclides and metals are heterogeneously distributed both within soil samples and within individual Th-enriched aggregates, which are characterised as low-density mineral bulk particles with high density material inclusions, where Th as well as several metals are highly concentrated. For these sites, it is important to take into account how these inhomogeneous distributions could affect the overall environmental behaviour of Th and progeny upon weathering due to human or environmental factors. Moreover, the estimated size of the Th-containing inclusions as determined in this work represents information of importance for the characterization of radionuclides and toxic metals exposure, as well as for assessing the viability of mining for Th and rare-earth metals in the Fen Complex and the associated environmental impact. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000535130500005 |
Publication Date |
2020-04-27 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
|
ISSN |
0265-931x |
ISBN ![sorted by ISBN field, descending order (down)](img/sort_desc.gif) |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.3 |
Times cited |
|
Open Access |
|
Notes |
|
Approved |
Most recent IF: 2.3; 2020 IF: 2.31 |
Call Number |
UA @ admin @ c:irua:181195 |
Serial |
8229 |
Permanent link to this record |
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Author |
Castanheiro, A.; Wuyts, K.; Hofman, J.; Nuyts, G.; De Wael, K.; Samson, R. |
Title |
Morphological and elemental characterization of leaf-deposited particulate matter from different source types : a microscopic investigation |
Type |
A1 Journal article |
Year |
2021 |
Publication |
Environmental Science And Pollution Research |
Abbreviated Journal |
Environ Sci Pollut R |
Volume |
28 |
Issue |
20 |
Pages |
25716-25732 |
Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
Abstract |
Particulate matter (PM) deposition on urban green enables the collection of particulate pollution from a diversity of contexts, and insight into the physico-chemical profiles of PM is key for identifying main polluting sources. This study reports on the morphological and elemental characterization of PM2-10 deposited on ivy leaves from five different environments (forest, rural, roadside, train, industry) in the region of Antwerp, Belgium. Ca. 40,000 leaf-deposited particles were thoroughly investigated by particle-based analysis using scanning electron microscopy coupled with energy-dispersive X-ray spectroscopy (SEM/EDX) and their physico-chemical characteristics were explored for PM source apportionment purposes. The size distribution of all deposited particles was biased towards small-sized PM, with 32% of the particles smaller than 2.5 mu m (PM2.5) and median diameters of 2.80-3.09 mu m. The source type influenced both the particles' size and morphology (aspect ratio and shape), with roadside particles being overall the smallest in size and the most spherical. While forest and rural elemental profiles were associated with natural PM, the industry particles revealed the highest anthropogenic metal input. PM2-10 profiles for roadside and train sites were rather comparable and only distinguishable when evaluating the fine (2-2.5 mu m) and coarse (2.5-10 mu m) PM fractions separately, which enabled the identification of a larger contribution of combustion-derived particles (small, circular, Fe-enriched) at the roadside compared to the train. Random forest prediction model classified the source type correctly for 61-85% of the leaf-deposited PM. The still modest classification accuracy denotes the influence of regional background PM and demands for additional fingerprinting techniques to facilitate source apportionment. Nonetheless, the obtained results demonstrate the utility of leaf particle-based analysis to fingerprint and pinpoint source-specific PM, particularly when considering both the composition and size of leaf-deposited particles. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000609067300006 |
Publication Date |
2021-01-20 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
|
ISSN |
0944-1344; 1614-7499 |
ISBN ![sorted by ISBN field, descending order (down)](img/sort_desc.gif) |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.741 |
Times cited |
|
Open Access |
OpenAccess |
Notes |
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Approved |
Most recent IF: 2.741 |
Call Number |
UA @ admin @ c:irua:176082 |
Serial |
8282 |
Permanent link to this record |
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Author |
Álvarez-Martín, A.; De Winter, S.; Nuyts, G.; Hermans, J.; Janssens, K.; van der Snickt, G. |
Title |
Multi-modal approach for the characterization of resin carriers in Daylight Fluorescent Pigments |
Type |
A1 Journal article |
Year |
2020 |
Publication |
Microchemical Journal |
Abbreviated Journal |
Microchem J |
Volume |
159 |
Issue |
|
Pages |
105340 |
Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Antwerp Cultural Heritage Sciences (ARCHES) |
Abstract |
Almost seventy years after artists such as Frank Stella (1936), Andy Warhol (1928-1987), James Rosenquist (1933-2017), Herb Aach (1923-1985) and Richard Bowman (1918-2001) started to incorporate Daylight Fluorescent Pigments (DFPs) in their artworks, the extent of the conservation problems that are associated with these pigments has increased progressively. Since their first appearance on the market, their composition has constantly been improved in terms of permanency. However, conservation practices on the artworks that are used in, are complicated by the fact that the composition of DFPs is proprietary and the information provided by the manufactures is limited. To be able to propose adequate conservation strategies for artworks containing DFPs, a thorough understanding of the DFPs composition must be acquired. In contrast with previous research that concentrated on identification of the coloring dye, this paper focuses on the characterization of the resin, used as the carrier for the dye. The proposed approach, involving ATR-FTIR, SPME-GC-MS and XRF analysis, provided additional insights on the organic and inorganic components of the resin. Using this approach, we investigated historical DFPs and new formulations, as well as different series from the main manufacturing companies (DayGlo, Swada, Radiant Color and Kremer) in order to obtain a full characterization of DFPs used by the artists along the years. First, the initial PCA-assisted ATR-FTIR spectroscopy allowed for an efficient classification of the main monomers in the resin polymer. Next, a further distinction was made by mass spectrometry and XRF which were optimized to allow a more specific classification of the resin and for detection of additives. In this paper we show the potential of SPME-GC-MS, never applied for the characterization of artistic materials, at present undervalued for heritage science purposes. We anticipate that this information will be highly relevant in the future stability studies and for defining (preventive) conservation strategies of fluorescent artworks. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000598761400009 |
Publication Date |
2020-07-30 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0026-265x; 0026-265x |
ISBN ![sorted by ISBN field, descending order (down)](img/sort_desc.gif) |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
4.8 |
Times cited |
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Open Access |
|
Notes |
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Approved |
Most recent IF: 4.8; 2020 IF: 3.034 |
Call Number |
UA @ admin @ c:irua:175083 |
Serial |
8286 |
Permanent link to this record |
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Author |
Beltran, V.; Marchetti, A.; Nuyts, G.; Leeuwestein, M.; Sandt, C.; Borondics, F.; De Wael, K. |
Title |
Nanoscale analysis of historical paintings by means of O‐PTIR spectroscopy : the identification of the organic particles in L’Arlésienne (portrait of Madame Ginoux) by Van Gogh |
Type |
A1 Journal article |
Year |
2021 |
Publication |
Angewandte Chemie-International Edition |
Abbreviated Journal |
Angew Chem Int Edit |
Volume |
60 |
Issue |
42 |
Pages |
22753-22760 |
Keywords |
A1 Journal article; Art; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
Abstract |
Optical-photothermal infrared (O-PTIR) spectroscopy is a recently developed technique that provides spectra comparable to traditional transmission FTIR spectroscopy with nanometric spatial resolution. Hence, O-PTIR is a promising candidate for the analysis of historical paintings, as well as other cultural heritage objects, but its potential has not yet been evaluated. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000694015700001 |
Publication Date |
2021-06-24 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
|
ISSN |
1433-7851; 0570-0833 |
ISBN ![sorted by ISBN field, descending order (down)](img/sort_desc.gif) |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
11.994 |
Times cited |
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Open Access |
OpenAccess |
Notes |
|
Approved |
Most recent IF: 11.994 |
Call Number |
UA @ admin @ c:irua:179989 |
Serial |
8291 |
Permanent link to this record |
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Author |
Al-Emam, E.; Beltran, V.; De Meyer, S.; Nuyts, G.; Wetemans, V.; De Wael, K.; Caen, J.; Janssens, K. |
Title |
Removal of a past varnish treatment from a 19th-century Belgian wall painting by means of a solvent-loaded double network hydrogel |
Type |
A1 Journal article |
Year |
2021 |
Publication |
Polymers |
Abbreviated Journal |
Polymers-Basel |
Volume |
13 |
Issue |
16 |
Pages |
2651-20 |
Keywords |
A1 Journal article; Art; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Antwerp Cultural Heritage Sciences (ARCHES); Antwerp Electrochemical and Analytical Sciences Lab (A-Sense Lab); Antwerp X-ray Imaging and Spectroscopy (AXIS) |
Abstract |
Polymeric materials have been used by painting conservator-restorers as consolidants and/or varnishes for wall paintings. The application of these materials is carried out when confronting loose paint layers or as a protective coating. However, these materials deteriorate and cause physiochemical alterations to the treated surface. In the past, the monumental neo-gothic wall painting 'The Last Judgment' in the chapel of Sint-Jan Berchmanscollege in Antwerp, Belgium was treated with a synthetic polymeric material. This varnish deteriorated significantly and turned brown, obscuring the paint layers. Given also that the varnish was applied to some parts of the wall painting and did not cover the entire surface, it was necessary to remove it in order to restore the original appearance of the wall painting. Previous attempts carried out by conservator-restorers made use of traditional cleaning methods, which led to damage of the fragile paint layers. Therefore, gel cleaning was proposed as a less invasive and more controllable method for gently softening and removing the varnish. The work started by identifying the paint stratigraphy and the deteriorated varnish via optical microscopy (OM), scanning electron microscopy coupled with energy-dispersive X-ray spectroscopy (SEM-EDX), X-ray diffraction (XRD), and Fourier-transform infrared (FTIR) spectroscopy. A polyvinyl alcohol-borax/agarose (PVA-B/AG) hydrogel loaded with a number of solvents/solvent mixtures was employed in a series of tests to select the most suitable hydrogel composite. By means of the hydrogel composite loaded with 10% propylene carbonate, it was possible to safely remove the brown varnish layer. The results were verified by visual examinations (under visible light 'VIS' and ultraviolet light 'UV') as well as OM and FTIR spectroscopy. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000690248000001 |
Publication Date |
2021-08-10 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
2073-4360 |
ISBN ![sorted by ISBN field, descending order (down)](img/sort_desc.gif) |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.364 |
Times cited |
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Open Access |
OpenAccess |
Notes |
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Approved |
Most recent IF: 3.364 |
Call Number |
UA @ admin @ c:irua:181567 |
Serial |
8470 |
Permanent link to this record |
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Author |
Schalm, O.; Nuyts, G.; Janssens, K. |
Title |
Some critical observations about the degradation of glass : the formation of lamellae explained |
Type |
A1 Journal article |
Year |
2021 |
Publication |
Journal Of Non-Crystalline Solids |
Abbreviated Journal |
J Non-Cryst Solids |
Volume |
569 |
Issue |
|
Pages |
120984 |
Keywords |
A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation) |
Abstract |
This study demonstrates that the mechanism responsible for the transformation of glass into a degradation layer is pH-dependent. In acid conditions, the transformed glass is homogeneous and brittle. In mild alkaline conditions, transformed glass is heterogeneous due to the presence of lamellae composed of silica nanoparticles and the occurrence of Ca-rich inclusions. The fundamental difference between acid and alkaline conditions cannot be explained by the currently accepted degradation mechanism based on ion exchange. To explain this critical observation, we propose a refined degradation mechanism based on existing knowledge that involves several inwardly moving reaction fronts. The fronts responsible for the transformation of the silicate network into amorphous silica are also responsible for the morphology of the transformed glass. We have identified the feedback mechanism that explains the formation of lamellae in alkaline conditions. |
Address |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000674487200009 |
Publication Date |
2021-06-20 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
|
ISSN |
0022-3093 |
ISBN ![sorted by ISBN field, descending order (down)](img/sort_desc.gif) |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
2.124 |
Times cited |
|
Open Access |
OpenAccess |
Notes |
|
Approved |
Most recent IF: 2.124 |
Call Number |
UA @ admin @ c:irua:179835 |
Serial |
8551 |
Permanent link to this record |
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Author |
Byrnes, I.; Rossbach, L.M.; Brede, D.A.; Grolimund, D.; Sanchez, D.F.; Nuyts, G.; Cuba, V.; Reinoso-Maset, E.; Salbu, B.; Janssens, K.; Oughton, D.; Scheibener, S.; Teien, H.-C.; Lind, O.C. |
Title |
Synchrotron-based X-ray fluorescence imaging elucidates uranium toxicokinetics in Daphnia magna |
Type |
A1 Journal article |
Year |
2023 |
Publication |
ACS nano |
Abbreviated Journal |
|
Volume |
17 |
Issue |
6 |
Pages |
5296-5305 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Antwerp X-ray Imaging and Spectroscopy (AXIS) |
Abstract |
A combination of synchrotron-based elemental anal-ysis and acute toxicity tests was used to investigate the biodistribution and adverse effects in Daphnia magna exposed to uranium nanoparticle (UNP, 3-5 nm) suspensions or to uranium reference (Uref) solutions. Speciation analysis revealed similar size distributions between exposures, and toxicity tests showed com-parable acute effects (UNP LC50: 402 mu g L-1 [336-484], Uref LC50: 268 mu g L-1 [229-315]). However, the uranium body burden was 3 -to 5-fold greater in UNP-exposed daphnids, and analysis of survival as a function of body burden revealed a similar to 5-fold higher specific toxicity from the Uref exposure. High-resolution X-ray fluorescence elemental maps of intact, whole daphnids from sublethal, acute exposures of both treatments revealed high uranium accumulation onto the gills (epipodites) as well as within the hepatic ceca and the intestinal lumen. Uranium uptake into the hemolymph circulatory system was inferred from signals observed in organs such as the heart and the maxillary gland. The substantial uptake in the maxillary gland and the associated nephridium suggests that these organs play a role in uranium removal from the hemolymph and subsequent excretion. Uranium was also observed associated with the embryos and the remnants of the chorion, suggesting uptake in the offspring. The identification of target organs and tissues is of major importance to the understanding of uranium and UNP toxicity and exposure characterization that should ultimately contribute to reducing uncertainties in related environmental impact and risk assessments. |
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Corporate Author |
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Place of Publication |
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Language |
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Wos |
000960129800001 |
Publication Date |
2023-03-15 |
Series Editor |
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Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1936-0851 |
ISBN ![sorted by ISBN field, descending order (down)](img/sort_desc.gif) |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
17.1 |
Times cited |
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Open Access |
OpenAccess |
Notes |
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Approved |
Most recent IF: 17.1; 2023 IF: 13.942 |
Call Number |
UA @ admin @ c:irua:196061 |
Serial |
8631 |
Permanent link to this record |
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Author |
Marchetti, A.; Beltran, V.; Storme, P.; Nuyts, G.; Van Der Meeren, L.; Skirtach, A.; Otten, E.; Debulpaep, M.; Watteeuw, L.; De Wael, K. |
Title |
All that glitters is not gold : unraveling the material secrets behind the preservation of historical brass |
Type |
A1 Journal article |
Year |
2023 |
Publication |
Journal of cultural heritage |
Abbreviated Journal |
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Volume |
63 |
Issue |
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Pages |
179-186 |
Keywords |
A1 Journal article; Engineering sciences. Technology; Art; History; Antwerp Cultural Heritage Sciences (ARCHES); Antwerp Electrochemical and Analytical Sciences Lab (A-Sense Lab) |
Abstract |
Brass is a relatively stable alloy but it tends to tarnish over time due to the interaction with the atmosphere. Thus, it is rare to observe centuries-old brass objects untouched by the passing of time. For this reason, the pristine appearance of hundreds of brass sequins in the Enclosed Gardens of Mechelen (reliquary altarpieces produced between 1530 and 1550) is remarkable. In this study, the chemical and metallographic characterization of such unexpectedly well-preserved objects is presented. The results revealed the reason for their stability to be a combination of high-quality materials (i.e. medium Zn content, low impurities) and optimal surface properties (i.e. high homogeneity, low roughness), indicating the high level of expertise of the craftsmen who produced them. Novel fundamental insights on the historical manufacturing method of metallic sequins were also obtained. |
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Wos |
001058894000001 |
Publication Date |
2023-08-14 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1296-2074 |
ISBN ![sorted by ISBN field, descending order (down)](img/sort_desc.gif) |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
Impact Factor |
3.1 |
Times cited |
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Open Access |
Not_Open_Access: Available from 15.08.2024 |
Notes |
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Approved |
Most recent IF: 3.1; 2023 IF: 1.838 |
Call Number |
UA @ admin @ c:irua:198113 |
Serial |
8830 |
Permanent link to this record |
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Author |
Menegaldo, B.; Aleccia, D.; Nuyts, G.; Amato, A.; Orsega, E.F.; Moro, G.; Balliana, E.; De Wael, K.; Moretto, L.M.; Beltran, V. |
Title |
Stories of the life of Saint George : materials and techniques from a Barbelli mural painting |
Type |
A1 Journal article |
Year |
2023 |
Publication |
Studies in conservation |
Abbreviated Journal |
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Volume |
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Issue |
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Pages |
1-14 |
Keywords |
A1 Journal article; Art; History; Antwerp Electrochemical and Analytical Sciences Lab (A-Sense Lab) |
Abstract |
Gian Giacomo Inchiocchio (1604-1656), better known as Barbelli, was one of the main exponents of Lombard painting of the seventeenth century. A large body of work is attributed to him, encompassing a wide range of drawings, murals, and oil paintings. However, despite his broad production, there are still many open questions regarding his painting techniques and materials. In this paper, a multi-analytical study of the cycle Stories of the life of Saint George that originally decorated the presbytery of the parish church of Casaletto Vaprio (Cremona, Italy) was performed, combining non-invasive techniques with the characterisation of selected micro samples. Results show that Barbelli used a very limited number of inorganic pigments, often mixing them together to create different colours and shades. Remains of caseinate and degradation products (i.e. weddellite and whewellite) related to the strappo intervention were also highlighted. The study helped to decipher the materials and technique of this painting, providing data that can be used as a reference to study his extensive production. |
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Wos |
001080139100001 |
Publication Date |
2023-10-04 |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
0039-3630; 2047-0584 |
ISBN ![sorted by ISBN field, descending order (down)](img/sort_desc.gif) |
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Additional Links |
UA library record; WoS full record |
Impact Factor |
0.8 |
Times cited |
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Open Access |
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Notes |
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Approved |
Most recent IF: 0.8; 2023 IF: 0.578 |
Call Number |
UA @ admin @ c:irua:200302 |
Serial |
9098 |
Permanent link to this record |
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Author |
Smets, B.; Boschker, H.T.S.; Wetherington, M.T.; Lelong, G.; Hidalgo-Martinez, S.; Polerecky, L.; Nuyts, G.; De Wael, K.; Meysman, F.J.R. |
Title |
Multi-wavelength Raman microscopy of nickel-based electron transport in cable bacteria |
Type |
A1 Journal article |
Year |
2024 |
Publication |
Frontiers in microbiology |
Abbreviated Journal |
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Volume |
15 |
Issue |
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Pages |
1208033-16 |
Keywords |
A1 Journal article |
Abstract |
Cable bacteria embed a network of conductive protein fibers in their cell envelope that efficiently guides electron transport over distances spanning up to several centimeters. This form of long-distance electron transport is unique in biology and is mediated by a metalloprotein with a sulfur-coordinated nickel (Ni) cofactor. However, the molecular structure of this cofactor remains presently unknown. Here, we applied multi-wavelength Raman microscopy to identify cell compounds linked to the unique cable bacterium physiology, combined with stable isotope labeling, and orientation-dependent and ultralow-frequency Raman microscopy to gain insight into the structure and organization of this novel Ni-cofactor. Raman spectra of native cable bacterium filaments reveal vibrational modes originating from cytochromes, polyphosphate granules, proteins, as well as the Ni-cofactor. After selective extraction of the conductive fiber network from the cell envelope, the Raman spectrum becomes simpler, and primarily retains vibrational modes associated with the Ni-cofactor. These Ni-cofactor modes exhibit intense Raman scattering as well as a strong orientation-dependent response. The signal intensity is particularly elevated when the polarization of incident laser light is parallel to the direction of the conductive fibers. This orientation dependence allows to selectively identify the modes that are associated with the Ni-cofactor. We identified 13 such modes, some of which display strong Raman signals across the entire range of applied wavelengths (405–1,064 nm). Assignment of vibrational modes, supported by stable isotope labeling, suggest that the structure of the Ni-cofactor shares a resemblance with that of nickel bis(1,2-dithiolene) complexes. Overall, our results indicate that cable bacteria have evolved a unique cofactor structure that does not resemble any of the known Ni-cofactors in biology. |
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Wos |
001189511900001 |
Publication Date |
2024-03-08 |
Series Editor |
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Edition |
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ISSN |
1664-302x |
ISBN ![sorted by ISBN field, descending order (down)](img/sort_desc.gif) |
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Additional Links |
UA library record; WoS full record |
Impact Factor |
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Times cited |
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Open Access |
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Notes |
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Approved |
Most recent IF: NA |
Call Number |
UA @ admin @ c:irua:205115 |
Serial |
9214 |
Permanent link to this record |