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Author Nistor, L.; Van Tendeloo, G.; Amelinckx, S.; Shpanchenko, R.V.; van Landuyt, J.
Title Ordering and defects in BanTaxTiyO3n ternary oxides Type P1 Proceeding
Year 1994 Publication Electron Microscopy 1994, Vols 2a And 2b: Applications In Materials Sciences Abbreviated Journal
Volume Issue Pages 869-870
Keywords P1 Proceeding; Electron microscopy for materials research (EMAT)
Abstract
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos A1994BE09Y00422 Publication Date 0000-00-00
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN (up) 2-86883-226-1 ISBN Additional Links UA library record; WoS full record;
Impact Factor Times cited Open Access
Notes Approved no
Call Number UA @ lucian @ c:irua:104477 Serial 2504
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Author Vanschoenwinkel, J.; Vancauteren, M.; Van Passel, S.
Title How do western European farms behave and respond to climate change? A simultaneous irrigation-crop decision model Type A1 Journal article
Year 2022 Publication Climate change economics Abbreviated Journal
Volume 13 Issue 4 Pages 2250009-2250038
Keywords A1 Journal article; Economics; Engineering Management (ENM)
Abstract Most farm adaptations are reactive actions that run the risk of locking farm systems into suboptimal long-term trajectories. This is especially the case with regard to water management as water scarcity will be aggravated by climate change. This paper looks into farm irrigation choices in combination with crop choices because a proper crop choice has the potential to reduce water requirements. It proposes an extended Ricardian model to capture multiple adaptation decisions explicitly. The new simultaneous irrigation-crop farm decision model uses spatially detailed farm-level data of over 18,000 European farms on irrigation and seven different crop choices. The analysis shows that larger farmers and farmers in less water-scarce regions that use irrigation are more sensitive to temperature increases than rain-fed agriculture. This might be explained by the fact that these farmers do not experience the real cost of water scarcity because of which they take less efficient decisions.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000791485900001 Publication Date 2022-03-09
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN (up) 2010-0086 ISBN Additional Links UA library record; WoS full record
Impact Factor Times cited Open Access OpenAccess
Notes Approved Most recent IF: NA
Call Number UA @ admin @ c:irua:188680 Serial 7359
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Author Okamura, I.; Van Passel, S.; Fabri, C.; Senda, T.
Title A Ricardian analysis of climate change impacts on Japan's agriculture : accounting for solar radiation Type A1 Journal article
Year 2023 Publication Climate change economics Abbreviated Journal
Volume 14 Issue 4 Pages 2350022-2350025
Keywords A1 Journal article; Economics; Engineering Management (ENM)
Abstract This study evaluates the effects of climate change on the net revenue of farmers in Japan. We adopted the Ricardian model, which implicitly accounts for farmers’ full adaptation. The main findings of this study are as follows. First, the Ricardian regression shows that changes in temperature significantly impact farmers’ net revenue. In contrast, changes in precipitation have limited effects on farmers’ net revenue. The results of future predictions showed that the effects of climate change are positive across the country, with varying degrees between north and south. These results are more optimistic than those in the existing literature, which frequently reveal negative climate change impacts in southern Japan. However, it should be noted that this model assumes full adaptation and does not consider the transition costs of farmers, and understanding the actual adaptive measures is an important remaining issue.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 001075308800001 Publication Date 2023-08-06
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN (up) 2010-0086 ISBN Additional Links UA library record; WoS full record
Impact Factor Times cited Open Access
Notes Approved Most recent IF: NA
Call Number UA @ admin @ c:irua:199659 Serial 9223
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Author Zaryouh, H.; Verswyvel, H.; Bauwens, M.; Van Haesendonck, G.; Deben, C.; Lin, A.; De Waele, J.; Vermorken, J.B.; Koljenovic, S.; Bogaerts, A.; Lardon, F.; Smits, E.; Wouters, A.
Title De belofte van hoofdhalskankerorganoïden in kankeronderzoek : een blik op de toekomst Type A2 Journal article
Year 2023 Publication Onco-hemato : multidisciplinair tijdschrift voor oncologie Abbreviated Journal
Volume 17 Issue 7 Pages 54-58
Keywords A2 Journal article; Center for Oncological Research (CORE); Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT)
Abstract Hoofd-halskanker vormt een aanzienlijke uitdaging met bijna 900.000 nieuwe diagnoses per jaar, waarbij de jaarlijkse incidentie blijft stijgen. Vaak wordt de diagnose pas in een laat stadium gesteld, wat complexe behandelingen noodzakelijk maakt. Terugval van patiënten is helaas een veelvoorkomend probleem. De gemiddelde overlevingsduur is beperkt tot enkele maanden. Daarom is er een dringende behoefte om nieuwe, veelbelovende behandelingen te ontwikkelen voor patiënten met hoofd-halskanker. Voor het bereiken van deze vooruitgang spelen innovatieve studiemodellen een cruciale rol. Het ontwikkelen van deze nieuwe behandelingen start met laboratoriumonderzoek, waarbij traditionele tweedimensionale celculturen hun beperkingen hebben. Daarom verschuiven onderzoekers hun aandacht meer en meer naar geavanceerdere driedimensionale modellen, met hoofd-halskankerorganoïden als beloftevol nieuw model. Dit model behoudt immers zowel het genetische profiel als de morfologische kenmerken van de originele tumor van de hoofd-halskankerpatiënt. Hoofdhalskankerorganoïden bieden daarom de mogelijkheid om innovatieve behandelingen te testen en kunnen mogelijk zelfs de respons van een patiënt op bepaalde therapieën voorspellen. Hoewel tumororganoïden als ‘patiënt-in-het-lab’ veelbelovend zijn, zijn er uitdagingen te overwinnen, zoals de ontwikkelingstijd en de toepasbaarheid bij alle tumortypes, evenals het ontbreken van immuuncellen en andere micro-omgevingscomponenten. Er is daarom een grote behoefte aan gestandaardiseerde protocollen voor de ontwikkeling van organoïden en verkorting van de ontwikkelingstijd. Concluderend bieden driedimensionale hoofd-halskankerorganoïden een veelbelovend perspectief voor de toekomst van kankerbehandelingen. Ze hebben het potentieel om bij te dragen aan de ontwikkeling van gepersonaliseerde behandelingen en zo de overlevingskansen van kankerpatiënten te verbeteren. Het is echter belangrijk om hun voorspellend vermogen en toepassingsmogelijkheden verder te onderzoeken, voordat ze op grote schaal worden geïmplementeerd.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos Publication Date
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN (up) 2030-2738 ISBN Additional Links UA library record
Impact Factor Times cited Open Access
Notes Approved Most recent IF: NA
Call Number UA @ admin @ c:irua:202271 Serial 9004
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Author Gielis, J.
Title Er bestaan geen absurde, irrationele, onregelmatige of onderling niet-onmeetbare meetkundige getallen Type A2 Journal article
Year 2021 Publication Wiskunde en onderwijs Abbreviated Journal
Volume 47 Issue 188 Pages 23-33
Keywords A2 Journal article; Sustainable Energy, Air and Water Technology (DuEL)
Abstract
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos Publication Date
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN (up) 2032-0485 ISBN Additional Links UA library record
Impact Factor Times cited Open Access
Notes Approved Most recent IF: NA
Call Number UA @ admin @ c:irua:183083 Serial 7934
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Author Kocabas, T.; Cakir, D.; Gulseren, O.; Ay, F.; Perkgoz, N.K.; Sevik, C.
Title A distinct correlation between the vibrational and thermal transport properties of group VA monolayer crystals Type A1 Journal article
Year 2018 Publication Nanoscale Abbreviated Journal
Volume 10 Issue 16 Pages 7803-7812
Keywords A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)
Abstract The investigation of thermal transport properties of novel two-dimensional materials is crucially important in order to assess their potential to be used in future technological applications, such as thermoelectric power generation. In this respect, the lattice thermal transport properties of the monolayer structures of group VA elements (P, As, Sb, Bi, PAs, PSb, PBi, AsSb, AsBi, SbBi, P3As1, P3Sb1, P1As3, and As3Sb1) with a black phosphorus like puckered structure were systematically investigated by first-principles calculations and an iterative solution of the phonon Boltzmann transport equation. Phosphorene was found to have the highest lattice thermal conductivity, , due to its low average atomic mass and strong interatomic bonding character. As a matter of course, anisotropic was obtained for all the considered materials, owing to anisotropy in frequency values and phonon group velocities calculated for these structures. However, the determined linear correlation between the anisotropy in the values of P, As, and Sb is significant. The results corresponding to the studied compound structures clearly point out that thermal (electronic) conductivity of pristine monolayers might be suppressed (improved) by alloying them with the same group elements. For instance, the room temperature of PBi along the armchair direction was predicted to be as low as 1.5 W m(-1) K-1, whereas that of P was predicted to be 21 W m(-1) K-1. In spite of the apparent differences in structural and vibrational properties, we peculiarly revealed an intriguing correlation between the values of all the considered materials as = c(1) + c(2)/m(2), in particular along the zigzag direction. Furthermore, our calculations on compound structures clearly showed that the thermoelectric potential of these materials can be improved by suppressing their thermal properties. The presence of ultra-low values and high electrical conductivity (especially along the armchair direction) makes this class of monolayers promising candidates for thermoelectric applications.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000431030000054 Publication Date 2018-03-22
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN (up) 2040-3364; 2040-3372 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor Times cited Open Access
Notes Approved no
Call Number UA @ admin @ c:irua:193785 Serial 7388
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Author Sarikurt, S.; Çakir, D.; Keceli, M.; Sevik, C.
Title The influence of surface functionalization on thermal transport and thermoelectric properties of MXene monolayers Type A1 Journal article
Year 2018 Publication Nanoscale Abbreviated Journal
Volume 10 Issue 18 Pages 8859-8868
Keywords A1 Journal article; Engineering sciences. Technology; Condensed Matter Theory (CMT)
Abstract The newest members of a two-dimensional material family, involving transition metal carbides and nitrides (called MXenes), have garnered increasing attention due to their tunable electronic and thermal properties depending on the chemical composition and functionalization. This flexibility can be exploited to fabricate efficient electrochemical energy storage (batteries) and energy conversion (thermoelectric) devices. In this study, we calculated the Seebeck coefficients and lattice thermal conductivity values of oxygen terminated M2CO2 (where M = Ti, Zr, Hf, Sc) monolayer MXene crystals in two different functionalization configurations (model-II (MD-II) and model-III (MD-III)), using density functional theory and Boltzmann transport theory. We estimated the thermoelectric figure-of-merit, zT, of these materials by two different approaches, as well. First of all, we found that the structural model (i.e. adsorption site of oxygen atom on the surface of MXene) has a paramount impact on the electronic and thermoelectric properties of MXene crystals, which can be exploited to engineer the thermoelectric properties of these materials. The lattice thermal conductivity kappa(l), Seebeck coefficient and zT values may vary by 40% depending on the structural model. The MD-III configuration always has the larger band gap, Seebeck coefficient and zT, and smaller kappa(l) as compared to the MD-II structure due to a larger band gap, highly flat valence band and reduced crystal symmetry in the former. The MD-III configuration of Ti2CO2 and Zr2CO2 has the lowest kappa(l) as compared to the same configuration of Hf2CO2 and Sc2CO2. Among all the considered structures, the MD-II configuration of Hf2CO2 has the highest kappa(l), and Ti2CO2 and Zr2CO2 in the MD-III configuration have the lowest kappa(l). For instance, while the band gap of the MD-II configuration of Ti2CO2 is 0.26 eV, it becomes 0.69 eV in MD-III. The zT(max) value may reach up to 1.1 depending on the structural model of MXene.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000432096400055 Publication Date 2018-04-06
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN (up) 2040-3364; 2040-3372 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor Times cited Open Access
Notes Approved no
Call Number UA @ admin @ c:irua:193788 Serial 8654
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Author Lindeboom, R.E.F.; Ilgrande, C.; Carvajal-Arroyo, J.M.; Coninx, I.; Van Hoey, O.; Roume, H.; Morozova, J.; Udert, K.M.; Sas, B.; Paille, C.; Lasseur, C.; Ilyin, V.; Clauwaert, P.; Leys, N.; Vlaeminck, S.E.
Title Nitrogen cycle microorganisms can be reactivated after Space exposure Type A1 Journal article
Year 2018 Publication Scientific reports Abbreviated Journal
Volume 8 Issue Pages 13783
Keywords A1 Journal article; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL)
Abstract Long-term human Space missions depend on regenerative life support systems (RLSS) to produce food, water and oxygen from waste and metabolic products. Microbial biotechnology is efficient for nitrogen conversion, with nitrate or nitrogen gas as desirable products. A prerequisite to bioreactor operation in Space is the feasibility to reactivate cells exposed to microgravity and radiation. In this study, microorganisms capable of essential nitrogen cycle conversions were sent on a 44-days FOTON-M4 flight to Low Earth Orbit (LEO) and exposed to 10(-3)-10(-4) g (gravitational constant) and 687 +/- 170 mu Gy (Gray) d(-1) (20 +/- 4 degrees C), about the double of the radiation prevailing in the International Space Station (ISS). After return to Earth, axenic cultures, defined and reactor communities of ureolytic bacteria, ammonia oxidizing archaea and bacteria, nitrite oxidizing bacteria, denitrifiers and anammox bacteria could all be reactivated. Space exposure generally yielded similar or even higher nitrogen conversion rates as terrestrial preservation at a similar temperature, while terrestrial storage at 4 degrees C mostly resulted in the highest rates. Refrigerated Space exposure is proposed as a strategy to maximize the reactivation potential. For the first time, the combined potential of ureolysis, nitritation, nitratation, denitrification (nitrate reducing activity) and anammox is demonstrated as key enabler for resource recovery in human Space exploration.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000444501200063 Publication Date 2018-09-07
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN (up) 2045-2322 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor Times cited Open Access
Notes Approved no
Call Number UA @ admin @ c:irua:153641 Serial 8309
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Author Peng, L.; Sun, J.; Liu, Y.; Dai, X.; Ni, B.-J.
Title Nitrous oxide production in a granule-based partial nitritation reactor : a model-based evaluation Type A1 Journal article
Year 2017 Publication Scientific reports Abbreviated Journal
Volume 7 Issue Pages 45609
Keywords A1 Journal article; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL)
Abstract Sustainable wastewater treatment has been attracting increasing attentions over the past decades. However, the production of nitrous oxide (N2O), a potent GHG, from the energy-efficient granule-based autotrophic nitrogen removal is largely unknown. This study applied a previously established N2O model, which incorporated two N2O production pathways by ammonia-oxidizing bacteria (AOB) (AOB denitrification and the hydroxylamine (NH2OH) oxidation). The two-pathway model was used to describe N2O production from a granule-based partial nitritation (PN) reactor and provide insights into the N2O distribution inside granules. The model was evaluated by comparing simulation results with N2O monitoring profiles as well as isotopic measurement data from the PN reactor. The model demonstrated its good predictive ability against N2O dynamics and provided useful information about the shift of N2O production pathways inside granules for the first time. The simulation results indicated that the increase of oxygen concentration and granule size would significantly enhance N2O production. The results further revealed a linear relationship between N2O production and ammonia oxidation rate (AOR) (R-2 = 0.99) under the conditions of varying oxygen levels and granule diameters, suggesting that bulk oxygen and granule size may exert an indirect effect on N2O production by causing a change in AOR.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000398238200001 Publication Date 2017-04-03
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN (up) 2045-2322 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor Times cited Open Access
Notes Approved no
Call Number UA @ admin @ c:irua:142397 Serial 8311
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Author Grunert, O.; Robles-Aguilar, A.A.; Hernandez-Sanabria, E.; Schrey, S.D.; Reheul, D.; Van Labeke, M.-C.; Vlaeminck, S.E.; Vanderkerckhove, T.G.L.; Mysara, M.; Monsieurs, P.; Temperton, V.M.; Boon, N.; Jablonowski, N.D.
Title Tomato plants rather than fertilizers drive microbial community structure in horticultural growing media Type A1 Journal article
Year 2019 Publication Scientific reports Abbreviated Journal
Volume 9 Issue Pages 9561
Keywords A1 Journal article; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL)
Abstract Synthetic fertilizer production is associated with a high environmental footprint, as compounds typically dissolve rapidly leaching emissions to the atmosphere or surface waters. We tested two recovered nutrients with slower release patterns, as promising alternatives for synthetic fertilizers: struvite and a commercially available organic fertilizer. Using these fertilizers as nitrogen source, we conducted a rhizotron experiment to test their effect on plant performance and nutrient recovery in juvenile tomato plants. Plant performance was significantly improved when organic fertilizer was provided, promoting higher shoot biomass. Since the microbial community influences plant nitrogen availability, we characterized the root-associated microbial community structure and functionality. Analyses revealed distinct root microbial community structure when different fertilizers were supplied. However, plant presence significantly increased the similarity of the microbial community over time, regardless of fertilization. Additionally, the presence of the plant significantly reduced the potential ammonia oxidation rates, implying a possible role of the rhizosheath microbiome or nitrification inhibition by the plant. Our results indicate that nitrifying community members are impacted by the type of fertilizer used, while tomato plants influenced the potential ammonia-oxidizing activity of nitrogen-related rhizospheric microbial communities. These novel insights on interactions between recovered fertilizers, plant and associated microbes can contribute to develop sustainable crop production systems.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000473418000003 Publication Date 2019-07-02
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN (up) 2045-2322 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor Times cited Open Access
Notes Approved no
Call Number UA @ admin @ c:irua:160582 Serial 8674
Permanent link to this record
 

 
Author Slavkovic, S.; Shoara, A.A.; Churcher, Z.R.; Daems, E.; De Wael, K.; Sobott, F.; Johnson, P.E.
Title DNA binding by the antimalarial compound artemisinin Type A1 Journal article
Year 2022 Publication Scientific reports Abbreviated Journal
Volume 12 Issue 1 Pages 133
Keywords A1 Journal article; Pharmacology. Therapy; Engineering sciences. Technology; Antwerp Electrochemical and Analytical Sciences Lab (A-Sense Lab)
Abstract Artemisinin (ART) is a vital medicinal compound that is used alone or as part of a combination therapy against malaria. ART is thought to function by attaching to heme covalently and alkylating a range of proteins. Using a combination of biophysical methods, we demonstrate that ART is bound by three-way junction and duplex containing DNA molecules. Binding of ART by DNA is first shown for the cocaine-binding DNA aptamer and extensively studied using this DNA molecule. Isothermal titration calorimetry methods show that the binding of ART is both entropically and enthalpically driven at physiological NaCl concentration. Native mass spectrometry methods confirm DNA binding and show that a non-covalent complex is formed. Nuclear magnetic resonance spectroscopy shows that ART binds at the three-way junction of the cocaine-binding aptamer, and that binding results in the folding of the structure-switching variant of this aptamer. This structure-switching ability was exploited using the photochrome aptamer switch assay to demonstrate that ART can be detected using this biosensing assay. This study is the first to demonstrate the DNA binding ability of ART and should lay the foundation for further work to study implications of DNA binding for the antimalarial activity of ART.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000740510500120 Publication Date 2022-01-07
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN (up) 2045-2322 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor Times cited Open Access OpenAccess
Notes Approved no
Call Number UA @ admin @ c:irua:184507 Serial 8851
Permanent link to this record
 

 
Author Shi, P.-J.; Xu, Q.; Sandhu, H.S.; Gielis, J.; Ding, Y.-L.; Li, H.-R.; Dong, X.-B.
Title Comparison of dwarf bamboos (Indocalamus sp.) leaf parameters to determine relationship between spatial density of plants and total leaf area per plant Type A1 Journal article
Year 2015 Publication Ecology and evolution Abbreviated Journal
Volume 5 Issue 20 Pages 4578-4589
Keywords A1 Journal article; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL)
Abstract The relationship between spatial density and size of plants is an important topic in plant ecology. The self-thinning rule suggests a −3/2 power between average biomass and density or a −1/2 power between stand yield and density. However, the self-thinning rule based on total leaf area per plant and density of plants has been neglected presumably because of the lack of a method that can accurately estimate the total leaf area per plant. We aimed to find the relationship between spatial density of plants and total leaf area per plant. We also attempted to provide a novel model for accurately describing the leaf shape of bamboos. We proposed a simplified Gielis equation with only two parameters to describe the leaf shape of bamboos one model parameter represented the overall ratio of leaf width to leaf length. Using this method, we compared some leaf parameters (leaf shape, number of leaves per plant, ratio of total leaf weight to aboveground weight per plant, and total leaf area per plant) of four bamboo species of genus Indocalamus Nakai (I. pedalis (Keng) P.C. Keng, I. pumilus Q.H. Dai and C.F. Keng, I. barbatus McClure, and I. victorialis P.C. Keng). We also explored the possible correlation between spatial density and total leaf area per plant using log-linear regression. We found that the simplified Gielis equation fit the leaf shape of four bamboo species very well. Although all these four species belonged to the same genus, there were still significant differences in leaf shape. Significant differences also existed in leaf area per plant, ratio of leaf weight to aboveground weight per plant, and leaf length. In addition, we found that the total leaf area per plant decreased with increased spatial density. Therefore, we directly demonstrated the self-thinning rule to improve light interception.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000363731500008 Publication Date 2015-09-30
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN (up) 2045-7758 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor Times cited Open Access
Notes Approved no
Call Number UA @ admin @ c:irua:128662 Serial 7691
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Author Lin, S.; Zhang, L.; Reddy, G.V.P.; Hui, C.; Gielis, J.; Ding, Y.; Shi, P.
Title A geometrical model for testing bilateral symmetry of bamboo leaf with a simplified Gielis equation Type A1 Journal article
Year 2016 Publication Ecology and evolution Abbreviated Journal
Volume 6 Issue 19 Pages 6798-6806
Keywords A1 Journal article; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL)
Abstract The size and shape of plant leaves change with growth, and an accurate description of leaf shape is crucial for describing plant morphogenesis and development. Bilateral symmetry, which has been widely observed but poorly examined, occurs in both dicot and monocot leaves, including all nominated bamboo species (approximately 1,300 species), of which at least 500 are found in China. Although there are apparent differences in leaf size among bamboo species due to genetic and environmental profiles, bamboo leaves have bilateral symmetry with parallel venation and appear similar across species. Here, we investigate whether the shape of bamboo leaves can be accurately described by a simplified Gielis equation, which consists of only two parameters (leaf length and shape) and produces a perfect bilateral shape. To test the applicability of this equation and the occurrence of bilateral symmetry, we first measured the leaf length of 42 bamboo species, examining >500 leaves per species. We then scanned 30 leaves per species that had approximately the same length as the median leaf length for that species. The leaf-shape data from scanned profiles were fitted to the simplified Gielis equation. Results confirmed that the equation fits the leaf-shape data extremely well, with the coefficients of determination being 0.995 on average. We further demonstrated the bilateral symmetry of bamboo leaves, with a clearly defined leaf-shape parameter of all 42 bamboo species investigated ranging from 0.02 to 0.1. This results in a simple and reliable tool for precise determination of bamboo species, with applications in forestry, ecology, and taxonomy.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000385626100003 Publication Date 2016-09-02
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN (up) 2045-7758 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor Times cited Open Access
Notes Approved no
Call Number UA @ admin @ c:irua:144547 Serial 7998
Permanent link to this record
 

 
Author Satyawali, Y.; Van Roy, S.; Roevens, A.; Meynen, V.; Mullens, S.; Jochems, P.; Doyen, W.; Cauwenberghs, L.; Dejonghe, W.
Title Characterization and analysis of the adsorption immobilization mechanism of \beta-galactosidase on metal oxide powders Type A1 Journal article
Year 2013 Publication RSC advances Abbreviated Journal
Volume 3 Issue 46 Pages 24054-24062
Keywords A1 Journal article; Laboratory of adsorption and catalysis (LADCA); Sustainable Energy, Air and Water Technology (DuEL)
Abstract Immobilization of the enzymes plays a vital role in enhancing their applicability in a wide range of applications, thus ensuring the use of sustainable enzymatic processes over the conventional chemical processes on an industrial scale. This study provides the background information for the selection and screening of inorganic metal oxide (MO) powders for their use as fillers in mixed matrix membranes for enzyme immobilization as the future aim. A total of 13 MOs, ranging in size from 0.01 μm to <5 μm, were tested for their performance as a support for enzyme (β-galactosidase) immobilization via adsorption. Alumina appeared to be the best performing MO with the amount and activity of the immobilized enzyme being 64 mg g−1 and up to 288 U g−1, respectively. The amount of immobilized enzyme on alumina (α-Al2O3 C and γ-Al2O3) was >3 times higher than ZrO2 (used as a reference MO in this study). Upon heat treatment at 900 °C, up to 15%, 52% and 42% decline was observed in the amount of immobilized enzyme in case of alumina metal oxides (MOs), ZrO2 and TiO2, respectively. The results suggested that both isoelectric point and surface area of the MO influence the immobilization. The most important observation in this study was that the bonding of the enzyme to the MO surface seems to be mediated by the bonding/interaction of the buffer to the enzyme.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000326745100030 Publication Date 2013-10-11
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN (up) 2046-2069 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor Times cited Open Access
Notes Approved no
Call Number UA @ admin @ c:irua:111300 Serial 7607
Permanent link to this record
 

 
Author Misseeuw, L.; Krajewska, A.; Pasternak, I.; Ciuk, T.; Strupinski, W.; Reekmans, G.; Adriaensens, P.; Geldof, D.; Geldof, D.; Van Vlierberghe, S.; Thienpont, H.; Dubruelf, P.; Vermeulen, N.
Title Optical-quality controllable wet-chemical doping of graphene through a uniform, transparent and low-roughness F4-TCNQ/MEK layer Type A1 Journal article
Year 2016 Publication RSC advances Abbreviated Journal
Volume Issue 106 Pages 104491-104501
Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Abstract Controllable chemical doping of graphene has already proven very useful for electronic applications, but when turning to optical and photonic applications, the additional requirement of having both a high transparency and a low surface roughness has, to our knowledge, not yet been fulfilled by any chemical dopant system reported so far. In this work, a new method that meets for the first time this opticalquality requirement while also providing efficient, controllable doping is presented. The method relies on F4-TCNQ dissolved in methyl ethyl ketone (MEK) yielding a uniform deposition after spin coating because of an extraordinary charge transfer interaction between the F4-TCNQ and MEK molecules. The formed F4-TCNQ/MEK layer exhibits a very high surface quality and optical transparency over the visible-infrared wavelength range between 550 and 1900 nm. By varying the dopant concentration of F4-TCNQ from 2.5 to 40 mg ml1 MEK, the doping effect can be controlled between Dn ¼ +5.73 1012 cm2 and +1.09 1013 cm2 for initially strongly p-type hydrogen-intercalated graphene grown on 6Hsilicon- carbide substrates, and between Dn ¼ +5.56 1012 cm2 and +1.04 1013 cm2 for initially weakly p-type graphene transferred on silicon samples. This is the first time that truly optical-quality chemical doping of graphene is demonstrated, and the obtained doping values exceed those reported before for F4-TCNQ-based graphene doping by as much as 50%.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000388111900075 Publication Date 2016-10-27
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN (up) 2046-2069 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor Times cited Open Access
Notes Approved no
Call Number UA @ admin @ c:irua:136405 Serial 8335
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Author van Loon, A.; Noble, P.; Krekeler, A.; van der Snickt, G.; Janssens, K.; Abe, Y.; Nakai, I.; Dik, J.
Title Artificial orpiment, a new pigment in Rembrandt's palette Type A1 Journal article
Year 2017 Publication Heritage science Abbreviated Journal
Volume 5 Issue Pages 26
Keywords A1 Journal article; Art; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Abstract This paper reports on how the application of macro X-ray fluorescence (MA-XRF) imaging, in combination with the re-examination of existing paint cross-sections, has led to the discovery of a new pigment in Rembrandt's palette: artificial orpiment. In the NWO Science4Arts 'ReVisRembrandt' project, novel chemical imaging techniques are being developed and applied to the study of Rembrandt's late paintings in order to help resolve outstanding questions and to gain a better understanding of his late enigmatic painting technique. One of the selected case studies is the Portrait of a Couple as Isaac and Rebecca, known as 'The Jewish Bride', dated c. 1665 and on view in the Rijksmuseum. During the re-installation of the Rijksmuseum in 2013, the picture was scanned using the Bruker M6 Jetstream MAXRF scanner. The resulting elemental distribution maps made it possible to distinguish many features in the painting, such as bone black remains of the original hat (P, Ca maps), and the now discolored smalt-rich background (Co, Ni, As, K maps). The arsenic (As) map also revealed areas of high-intensity in Isaac's sleeve and Rebecca's dress where it could be established that it was not related with the pigment smalt that also contains arsenic. This pointed to the presence of a yellow or orange arsenic-containing pigment, such as realgar or orpiment that is not associated with the artist's palette. Subsequent examination of existing paint cross-sections from these locations taken by Karin Groen in the 1990s identified isolated, almost perfectly round particles of arsenic sulfide. The round shape corresponds with published findings on a purified form of artificial orpiment glass obtained by dry processing, a sublimation reaction. In bright field, the particles characteristically exhibit a dark cross in the middle caused by internal light reflections. The results of additional non-invasive techniques (portable XRD and portable Raman) are discussed, as well as the implications of this finding and how it fits with Rembrandt's late experimental painting technique.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000404916400001 Publication Date 2017-06-02
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN (up) 2050-7445 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor Times cited 6 Open Access
Notes ; This research is part of the Science4Arts Program, funded by the Netherlands Organization for Scientific Research (NWO) (Grant No. SFA-11-12). GVdS is supported by the Baillet Latour Fund. The authors would like to thank Lisette Vos, Rijksmuseum Amsterdam, for assisting with the MA-XRF scanning; Arisa Izumi and Airi Hirayama, students of the Tokyo University of Science, and Frederik Vanmeert, University of Antwerp, for assisting with the pXRD and pRaman measurements. We are also grateful to Rob Erdmann, Rijksmuseum Amsterdam, who made the curtain viewer to facilitate comparison of the visible image with the elemental distribution maps of the painting. ; Approved Most recent IF: NA
Call Number UA @ admin @ c:irua:144864 Serial 5479
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Author Simoen, J.; De Meyer, S.; Vanmeert, F.; De Keyser, N.; Avranovich, E.; van der Snickt, G.; Van Loon, A.; Keune, K.; Janssens, K.
Title Combined Micro- and Macro scale X-ray powder diffraction mapping of degraded Orpiment paint in a 17th century still life painting by Martinus Nellius Type A1 Journal article
Year 2019 Publication Heritage science Abbreviated Journal
Volume 7 Issue 1 Pages 83
Keywords A1 Journal article; Art; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Antwerp Cultural Heritage Sciences (ARCHES)
Abstract The spontaneous chemical alteration of artists' pigment materials may be caused by several degradation processes. Some of these are well known while others are still in need of more detailed investigation and documentation. These changes often become apparent as color modifications, either caused by a change in the oxidation state in the original material or the formation of degradation products or salts, via simple or more complex, multistep reactions. Arsenic-based pigments such as orpiment (As2S3) or realgar (alpha-As4S4) are prone to such alterations and are often described as easily oxidizing upon exposure to light. Macroscopic X-ray powder diffraction (MA-XRPD) imaging on a sub area of a still life painting by the 17th century Dutch painter Martinus Nellius was employed in combination with microscopic (mu-) XRPD imaging of a paint cross section taken in the area imaged by MA-XRPD. In this way, the in situ formation of secondary metal arsenate and sulfate species and their migration through the paint layer stack they originate from could be visualized. In the areas originally painted with orpiment, it could be shown that several secondary minerals such as schultenite (PbHAsO4), mimetite (Pb-5(AsO4)(3)Cl), palmierite (K2Pb(SO4)(2)) and syngenite (K2Ca(SO4)(2)center dot H2O) have formed. Closer inspection of the cross-sectioned paint layer stack with mu-XRPD illustrates that the arsenate minerals schultenite and mimetite have precipitated at the interface between the orpiment layer and the layer below that is rich in lead white, i.e. close to the depth of formation of the arsenate ions. The sulfate palmierite has mostly precipitated at the surface and upper layers of the painting.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000490592700001 Publication Date 2019-10-16
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN (up) 2050-7445 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor Times cited 2 Open Access
Notes ; The authors acknowledge financial support from the NWO (The Hague) Science4Arts 'ReVisRembrandt' project (AvL, JD), the GOA Project Solarpaint (University of Antwerp Research Council) (SdM) and the METOX project (Belgian Federal Science Policy) (FvM). Special thanks go to the support received from FWO, Brussels via projects G056619 N and G054719 N (GvdS, KJ) and from NWO, The Hague via project NICAS/3D2P (KK, NdK). Parts of the MA-XRPD scanner could be purchased thanks to InterReg Project Smart*Light. ; Approved Most recent IF: NA
Call Number UA @ admin @ c:irua:163693 Serial 5521
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Author Al-Emam, E.; Motawea, A.G.; Janssens, K.; Caen, J.
Title Evaluation of polyvinyl alcohol–borax/agarose (PVA–B/AG) blend hydrogels for removal of deteriorated consolidants from ancient Egyptian wall paintings Type A1 Journal article
Year 2019 Publication Heritage science Abbreviated Journal
Volume 7 Issue 7 Pages 22
Keywords A1 Journal article; Engineering sciences. Technology; Art; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Antwerp Cultural Heritage Sciences (ARCHES)
Abstract This study concerns the assessment of a new polyvinyl alcohol–borax/agarose blend hydrogel (PVA–B/AG) tailored for the conservation of ancient Egyptian wall paintings. The increasing problems of deteriorated consolidants affecting ancient wall paintings have attracted the interest of conservation scientists in the last 20 years. The ability of a new blend for removing aged Paraloid® B-72 layers from painted stone and plaster samples has been evaluated. The hydrogel blend was used to expose the aged Paraloid in a controlled manner to six different cleaning system (CS). CS1–CS4 consist of solvents or solvent mixtures; CS5 and CS6 are nanostructured fluids (NSFs). The evaluation of the removal process was carried out by quantitative and qualitative methods, namely, visual examination, 3D microscopy, contact angle and colorimetric measurements and by Fourier transform infra-red spectrometry in reflectance mode. The results showed that the PVA–B/AG blend hydrogel, loaded with specific cleaning systems, was able to remove deteriorated B-72 and allowed to restore the painted surface to a state close to the original one. The PVA–B/AG blend showed good workability, permitting it to be easily cut, shaped, applied and removed. It could also be verified by means of different investigation methods that the blend left no detectable residues. As a final realistic check of the method, the PVA–B/AG hydrogel loaded with the best functioning cleaning system (CS3) was used to remove an aged consolidant layer from an ancient Egyptian wall painting.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000463733900001 Publication Date 2019-04-05
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN (up) 2050-7445 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor Times cited 2 Open Access
Notes ; Ehab Al-Emam acknowledges the Egyptian Ministry of Higher Education for funding his PhD scholarship. ; Approved Most recent IF: NA
Call Number UA @ admin @ c:irua:158879 Serial 5615
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Author Legrand, S.; Vanmeert, F.; van der Snickt, G.; Alfeld, M.; de Nolf, W.; Dik, J.; Janssens, K.
Title Examination of historical paintings by state-of-the-art hyperspectral imaging methods : from scanning infra-red spectroscopy to computed X-ray laminography Type A1 Journal article
Year 2014 Publication Heritage science Abbreviated Journal
Volume 2 Issue Pages 13-11
Keywords A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Abstract The development of advanced methods for non-destructive selective imaging of painted works of art at the macroscopic level based on radiation in the X-ray and infrared range of the electromagnetic spectrum are concisely reviewed. Such methods allow to either record depth-selective, element-selective or species-selective images of entire paintings. Camera-based full field methods (that record the image data in parallel) can be discerned next to scanning methods (that build up distributions in a sequential manner by scanning a beam of radiation over the surface of an artefact). Six methods are discussed: on the one hand, macroscopic X-ray fluorescence and X-ray diffraction imaging and X-ray laminography and on the other hand macroscopic Mid and Near Infrared hyper- and full spectral imaging and Optical Coherence Tomography. These methods can be considered to be improved versions of the well-established imaging methods employed worldwide for examination of paintings, i.e., X-ray radiography and Infrared reflectography. Possibilities and limitations of these new imaging techniques are outlined.
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Publisher Place of Publication Editor
Language Wos Publication Date 2014-05-30
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN (up) 2050-7445 ISBN Additional Links UA library record
Impact Factor Times cited Open Access
Notes Approved Most recent IF: NA
Call Number UA @ admin @ c:irua:124629 Serial 5619
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Author Vermeulen, M.; Sanyova, J.; Janssens, K.
Title Identification of artificial orpiment in the interior decorations of the Japanese tower in Laeken, Brussels, Belgium Type A1 Journal article
Year 2015 Publication Heritage science Abbreviated Journal
Volume 3 Issue Pages Unsp 9
Keywords A1 Journal article; Art; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Abstract In this paper, we used a multi-technique approach in order to identify the arsenic sulfide pigment used in the decorative panels of the Japanese tower in Laeken, Belgium. Our attention was drawn to this particular pigment because of its relatively good conservation state, despite its known tendency to fade over time when exposed to light. The pigment was used with different painting techniques, bound with oil and urushi in the lacquers and with an aqueous binder in the mat relief panels. In the latter case it is always applied as an underlayer mixed with ultramarine blue. This quite unusual pigment mixture also shows a good state of preservation. In this study, the orpiment used for the Japanese tower has been identified as an amorphous arsenic sulfide glass (AsxSx) with the aid of light microscopy, PLM, SEM-EDX and Raman microscopy. The pigment features different degrees of As4S4 monomer units in its structure, also known as realgar-like nano-phases. This most likely indicates different synthesis processes as the formation of these As4S4 monomers is dependent of the quenching temperature (Tq) to which the artificial pigment is exposed during the preparation phase.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000356920400001 Publication Date 2015-02-25
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN (up) 2050-7445 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor Times cited 17 Open Access
Notes ; We cordially thank Gunter Grundmann for his precious advice regarding PLM and arsenic sulfide glass. This research is made possible with the support of the Belgian Science Policy Office (BELSPO) through the research program Science for a Sustainable Development – SDD, “Long-term role and fate of metal-sulfides in painted works of art – S2ART” (SD/RI/04A). ; Approved Most recent IF: NA
Call Number UA @ admin @ c:irua:124904 Serial 5649
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Author De Meyer, S.; Vanmeert, F.; Vertongen, R.; van Loon, A.; Gonzalez, V.; van der Snickt, G.; Vandivere, A.; Janssens, K.
Title Imaging secondary reaction products at the surface of Vermeer's Girl with the Pearl Earring by means of macroscopic X-ray powder diffraction scanning Type A1 Journal article
Year 2019 Publication Heritage science Abbreviated Journal
Volume 7 Issue 1 Pages 67
Keywords A1 Journal article; Art; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Antwerp Cultural Heritage Sciences (ARCHES)
Abstract The use of non-invasive macroscopic imaging techniques is becoming more prevalent in the field of cultural heritage, especially to avoid invasive procedures that damage valuable artworks. For this purpose, an X-ray powder diffraction scanner (MA-XRPD) capable of visualising crystalline compounds in a highly specific manner was recently developed. Many inorganic pigments present in paintings fall into this category of materials. In this study, the 17th century oil painting Girl with a Pearl Earring (c. 1665) by Johannes Vermeer was analysed with a combination of transmission and reflection mode MA-XRPD. By employing this scanner in reflection mode, the relative sensitivity for compounds that are present at the paint surface could be increased, establishing it as a highly relevant technique for investigating the degradation processes that are ongoing at paint surfaces. Many of the original pigments employed by Vermeer could be identified, along with four secondary alteration products: gypsum (CaSO4 center dot 2H(2)O), anglesite (PbSO4), palmierite (K2Pb(SO4)(2)) and weddellite (CaC2O4 center dot 2H(2)O). The formation of gypsum was linked to the presence of chalk in the upper glaze layer while the formation of palmierite and weddellite is driven by the presence of lake pigments (and their substrates). In this manner, MA-XRPD can also be used to pinpoint locations relevant for sampling and synchrotron mu-XRPD analysis, which provides information on the microscopic make-up of the paint. A paint cross-section taken from an area rich in palmierite was analysed with synchrotron mu-XRPD, which confirmed the presence of this secondary compound at the interface of the upper paint layer with the ground layer as well as the presence of anglesite in the ground layer. The capacity of MA-XRPD to identify and chart secondary alteration products in a non-invasive manner has only very recently been demonstrated and makes it a highly relevant technique for the assessment of the chemical condition of works of art.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000484938100001 Publication Date 2019-09-08
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN (up) 2050-7445 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor Times cited 5 Open Access
Notes ; The authors would like to thank Interreg Vlaanderen-Nederland for funding to help develop the MA-rXRPD scanner. This project was made possible with support from the Johan Maurits Compagnie Foundation. This study was supported by Interreg and CALIPSOplus (Grant 730872). ; Approved Most recent IF: NA
Call Number UA @ admin @ c:irua:162801 Serial 5653
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Author Delaney, J.K.; Conover, D.M.; Dooley, K.A.; Glinsman, L.; Janssens, K.; Loew, M.
Title Integrated X-ray fluorescence and diffuse visible-to-near-infrared reflectance scanner for standoff elemental and molecular spectroscopic imaging of paints and works on paper Type A1 Journal article
Year 2018 Publication Heritage science Abbreviated Journal
Volume 6 Issue 6 Pages 31
Keywords A1 Journal article; Art; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Abstract Prior studies have shown the improved ability to identify artists' pigments by combining results from X-ray fluorescence (XRF), which provides elemental information, with reflectance spectroscopy in the visible to near infrared (400-1000 nm) that provides information on electronic transitions. Extending the spectral range of reflectance spectroscopy into the UV, 350-400 nm, allows identification of several white pigments since their electronic transitions occur in this region (e.g., zinc white and rutile and anatase forms of titanium white). Extending the range further into the infrared, out to 2500 nm, provides information on vibrational transitions of various functional groups, such as hydroxyl, carbonate, and methyl groups. This allows better identification of mineral-based pigments and some paint binders. The combination of elemental information with electronic and vibrational transitions provides a more robust method to identify artists' materials in situ. The collection of both sets of spectral information across works of art, such as paintings and works on paper, allows generating a more complete map of artists' materials. Here, we describe a 2-D scanner that simultaneously collects XRF spectra and reflectance spectra from 350 to 2500 nm across the surfaces of works of art. The scanner consists of a stationary, single pixel XRF spectrometer and fiber optic reflectance spectrometer along with a 2-D position-controlled easel that moves the artwork in front of the two detection systems. The dual-mode scanner has been tested on a variety of works of art from illuminated manuscripts (0.1 x 0.1 m(2)) to paintings as large as 1.7 x 1.9 m(2). The scanner is described and two sets of results are presented. The first is the XRF scanning of a large warped panel painting by Andrea del Sarto titled Charity. The second is a combined XRF and reflectance scan of Georges Seurat's painting titled Haymakers at Montfermeil. The XRF was collected at 1 mm spatial sampling and the reflectance spectral data at 3 mm. Combining the results from the data sets was found to enhance the identification of pigments as well as yield distribution maps, in spite of the relatively low reflectance spatial sampling. The elemental and reflectance maps allowed the identification and mapping of lead white, cobalt blue, viridian, ochres, and likely chrome yellow. The maps also provide information on the mixing of pigments. While the reflectance image cube has 10-20x larger spatial samples than desired, the elimination of having to use two hyperspectral cameras to cover the range from 400 to 2500 nm makes for a low cost dual modality scanner.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000433601900001 Publication Date 2018-05-18
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN (up) 2050-7445 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor Times cited 7 Open Access
Notes ; The authors acknowledge funding from the National Science Foundation (Award 1041827). J.K.D. and D.M.C. acknowledge funding from the Andrew W. Mellon and Samuel H. Kress Foundations. The authors are grateful to David Martin and Dennis Murphy of SmartDrive Ltd., Gary Fager of Malvern PANalytical, and Gao Ning of XOS for advice. KJ acknowledges support from EU-InterReg project SmartLight and from GOA Project SolarPaint (University of Antwerp Research Council). ; Approved Most recent IF: NA
Call Number UA @ admin @ c:irua:152039 Serial 5665
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Author De Keyser, N.; van der Snickt, G.; Van Loon, A.; Legrand, S.; Wallert, A.; Janssens, K.
Title Jan Davidsz. de Heem (1606-1684): a technical examination of fruit and flower still lifes combining MA-XRF scanning, cross-section analysis and technical historical sources Type A1 Journal article
Year 2017 Publication Heritage science Abbreviated Journal
Volume 5 Issue Pages 38
Keywords A1 Journal article; Art; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Abstract This article discusses the technical examination of five flower and fruit still life paintings by the seventeenth century artist Jan Davidsz. de Heem (1606-1684). The painter is known for his meticulously composed and finely detailed still life paintings and is a master in imitating the surface textures of various fruits, flowers, and objects. Macro X-ray fluorescence (MA-XRF) scanning experiments were supplemented with a study of paint cross-sections and contemporary art technical sources with the aim of reconstructing the complex build-up of the overall lay-in of the composition and individual subjects. MA-XRF provided information on the distribution of key chemical elements present in painting materials and made it possible to recapture evidence of the different phases in the artist's working methods: from the application of the ground layers, to De Heem's characteristic oval-shaped underpaintings, and finally, the superposition of multiple paint layers in the working up of the paintings. SEM-EDX analysis of a limited number of paint cross-sections complemented the chemical images with local and layer-specific information on the microscale, providing more accuracy on the layer sequence and enabling the study of elements with a low atomic number for which the non-invasive technique is less sensitive. The results from this technical examination were in addition compared with recipes and paint instructions, to obtain a better understanding of the relation between the general practice and actual painting technique of Jan Davidsz. de Heem. Ultimately, this combined approach uncovered new information on De Heem's artistic practice and demonstrated the complementarity of the methods.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000410414000001 Publication Date 2017-08-14
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN (up) 2050-7445 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor Times cited 5 Open Access
Notes ; This work is an extension of the Master thesis in Conservation-restoration (University of Antwerp, 2015-2016) of Nouchka De Keyser. Thesis supervisors were Dr. Geert Van der Snickt (Cultural heritage scientist, AXES, UA) and Dr. Olivier Schalm (Research scientist, UA). This research was supported by the Baillet Latour fund. The authors gratefully acknowledge the involved institutes (Rijksmuseum, the Mauritshuis and KMSKA) for the opportunity to examine the still life paintings of Jan Davidsz. de Heem. A great thanks is therefore due to Petria Noble, Pieter Roelofs, Anna Krekeler, Susan Smelt, Robert Erdmann, Abbie Vandivere, Edwin Buijsen and Masayuki Hinoue. SEM-EDX measurements were performed by Katrien Keune, scientific researcher at the Rijksmuseum. ; Approved Most recent IF: NA
Call Number UA @ admin @ c:irua:145628 Serial 5681
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Author da Silva, A.T.; Legrand, S.; van der Snickt, G.; Featherstone, R.; Janssens, K.; Bottinelli, G.
Title MA-XRF imaging on Rene Magritte's La condition humaine : insights into the artist's palette and technique and the discovery of a third quarter of La pose enchantee Type A1 Journal article
Year 2017 Publication Heritage science Abbreviated Journal
Volume 5 Issue Pages 37
Keywords A1 Journal article; Art; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Abstract Magritte's composition La condition humaine, 1935 was found to conceal under its paint layers an entire quarter of a lost composition by the artist, until recently only known from a small black/white catalogue illustration-La pose enchantee, 1927. This study is the latest contribution to the discovery of the artist's missing painting, now known to have been cut into four parts and re-used by Magritte as the support for new compositions. Non-destructive analytical and examination methods and specifically macroscopic X-ray fluorescence (MAXRF) scanning and conventional X-ray radiography (XRR) were the two non-destructive analytical and examination methods used to study both compositions and add to the existing knowledge on the artist's palette during both periods. The first method is capable of identifying the presence and the distribution of key chemical elements present in artists' materials. In some instances elemental mapping provided useful information on the hidden painting, but conventional X-ray radiography (XRR) enabled a better visualisation of the form and paint application of the underlying composition. Furthermore, the turnover edges of the canvas reveal after over 80 years the artist's palette directly to the viewer. Additional XRF scanning of this exposed paint has confirmed and added to the existing research published to date of this lost painting, including a proposed colour reconstruction, but at the same time highlighting the need for further analytical research involving both non-destructive point analysis and the use of paint samples.
Address
Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000410413500001 Publication Date 2017-08-04
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN (up) 2050-7445 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor Times cited 7 Open Access
Notes ; ; Approved Most recent IF: NA
Call Number UA @ admin @ c:irua:145695 Serial 5696
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Author Dooley, K.A.; Gifford, E.M.; van Loon, A.; Noble, P.; Zeibel, J.G.; Conover, D.M.; Alfeld, M.; van der Snickt, G.; Legrand, S.; Janssens, K.; Dik, J.; Delaney, J.K.
Title Separating two painting campaigns in Saul and David, attributed to Rembrandt, using macroscale reflectance and XRF imaging spectroscopies and microscale paint analysis Type A1 Journal article
Year 2018 Publication Heritage science Abbreviated Journal
Volume 6 Issue 6 Pages 46
Keywords A1 Journal article; Art; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Abstract Late paintings of Rembrandt van Rijn (1606-1669) offer intriguing problems for both art historians and conservation scientists. In the research presented here, the key question addressed is whether observed stylistic differences in paint handling can be correlated with material differences. In Saul and David, in the collection of the Royal Picture Gallery Mauritshuis in The Hague, NL, the stylistic differences between the loose brushwork of Saul's cloak and the more detailed depiction of his turban and the figure of David have been associated with at least two painting stages since the late 1960s, but the attribution of each stage has been debated in the art historical literature. Stylistic evaluation of the paint handling in the two stages, based on magnified surface examination, is further described here. One of the research goals was to determine whether the stylistic differences could be further differentiated with macroscale and microscale methods of material analysis. To address this, selected areas of the painting having pronounced stylistic differences were investigated with two macroscopic chemical imaging methods, X-ray fluorescence and reflectance imaging spectroscopies. The pigments used were identified and their spatial distribution was mapped. The mapping results show that the passages rendered in more detail and associated stylistically with the first painting stage, such as the orange-red color of David's garment or the Greek key design in Saul's turban, were painted with predominately red ochre mixed with vermilion. The regions of loose, bold brushwork, such as the orange-red slashing strokes in the interior of Saul's cloak, associated with the second painting stage, were painted with predominately red ochre without vermilion. These macroscale imaging results were confirmed and extended with scanning electron microscopy with energy-dispersive X-ray spectroscopy (SEM-EDX) analysis of three cross-sections taken from regions of stylistic differences associated with the two painting stages, including one sample each from the right and left sleeve of David, and one from the interior of Saul's cloak. SEM-EDX also identified a trace component, barium sulfate, associated with the red ochre of the second stage revisions. Combining mapping information from two spectroscopic imaging methods with localized information from microscopic samples has clearly shown that the stylistic differences observed in the paint handling are affiliated with differences in the chemical composition of the paints.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000441205600001 Publication Date 2018-08-02
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN (up) 2050-7445 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor Times cited 3 Open Access
Notes ; The authors gratefully acknowledge the financial support through the NWO Science4Arts program (ReVisRembrandt Project 2012-2018) and the NSF SCI-ART program (Award 1041827). JKD acknowledges support from the Andrew W. Mellon and the Samuel H. Kress Foundations. SL is grateful for a doctoral scholarship from the Research Council of the University of Antwerp. GvdS and KJ acknowledge support from the Fund Baillet Latour. ; Approved Most recent IF: NA
Call Number UA @ admin @ c:irua:153119 Serial 5829
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Author Centeno, S.A.; Hale, C.; Caro, F.; Cesaratto, A.; Shibayama, N.; Delaney, J.; Dooley, K.; van der Snickt, G.; Janssens, K.; Stein, S.A.
Title Van Gogh's Irises and Roses : the contribution of chemical analyses and imaging to the assessment of color changes in the red lake pigments Type A1 Journal article
Year 2017 Publication Heritage science Abbreviated Journal
Volume 5 Issue Pages 18
Keywords A1 Journal article; Art; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Abstract Vincent van Gogh's still lifes Irises and Roses were investigated to shed light onto the degree to which the paintings had changed, both individually and in relation to each other since they were painted, particularly in regard to the fading of the red lakes. Non-invasive techniques, including macroscopic X-ray fluorescence mapping, reflectance imaging spectroscopy, and X-radiography, were combined with microanalytical techniques in a select number of samples. The in-depth microchemical analysis was necessary to overcome the complications that arise when evaluating by non-invasive methods alone the compositions of passages with complex layering and mixing of paints. The results obtained by these two approaches were complemented by color measurements performed on paint cross-sections and on protected edges, and with historical information provided by the artist's own descriptions, early reviews and reproductions, and the data was used to carry out digital color simulations that provided, to a certain extent, a visualization of how the paintings may have originally appeared.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000401365400001 Publication Date 2017-04-21
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN (up) 2050-7445 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor Times cited 21 Open Access
Notes ; ; Approved Most recent IF: NA
Call Number UA @ admin @ c:irua:143748 Serial 5903
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Author Harth, A.; van der Snickt, G.; Schalm, O.; Janssens, K.; Blanckaert, G.
Title The young Van Dyck's fingerprint : a technical approach to assess the authenticity of a disputed painting Type A1 Journal article
Year 2017 Publication Heritage science Abbreviated Journal
Volume 5 Issue Pages 22-13
Keywords A1 Journal article; Art; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Antwerp Cultural Heritage Sciences (ARCHES)
Abstract The painting Saint Jerome, part of the collection of the Maagdenhuis Museum (Antwerp, Belgium), is attributed to the young Anthony van Dyck (1613-1621) with reservations. The painting displays remarkable compositional and iconographic similarities with two early Van Dyck works (1618-1620) now in Museum Boijmans van Beuningen (Rotterdam) and Nationalmuseum (Stockholm). Despite these similarities, previous art historical research did not result in a clear attribution to this master. In this study, the works authenticity as a young Van Dyck painting was assessed from a technical perspective by employing a twofold approach. First, technical information on Van Dycks materials and techniques, here identified as his fingerprint, were defined based on a literature review. Second, the materials and techniques of the questioned Saint Jerome painting were characterized by using complementary imaging techniques: infrared reflectography, X-ray radiography and macro X-ray fluorescence scanning. The insights from this non-invasive research were supplemented with analysis of a limited number of cross-sections by means of field emission scanning electron microscopy coupled with energy dispersive X-ray spectroscopy. The results demonstrated that the questioned paintings materials and techniques deviate from Van Dycks fingerprint, thus making the authorship of this master very unlikely.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000403971300001 Publication Date 2017-05-12
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN (up) 2050-7445 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor Times cited 1 Open Access
Notes ; The authors are grateful to the staff of the Maagdenhuis Museum Antwerp, especially to Daniel Christiaens and Rudi van Velthoven, for their cooperation and enthusiastic support. Prof. Em. Claudine A. Chavannes-Mazel and Ph. D. student Alice Taatgen (University of Amsterdam) are acknowledged for the IRR recordings. We also would like to acknowledge Dr. Christina Currie (KIK/IRPA) and Catherine Fondaire (KIK/IRPA) for the XRR, and Eva Grieten (EMAT, University of Antwerp) for the FE-SEM-EDX. Finally, the authors wish to thank Prof. Dr. Katlijne van der Stighelen (University of Leuven) and Prof. Dr. Maximilaan Martens (Ghent University) for their art historical insights and additional comments. This research was supported by the Baillet Latour fund and Research Foundation Flanders (FWO). ; Approved Most recent IF: NA
Call Number UA @ admin @ c:irua:143633 Serial 5923
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Author van Loon, A.; Vandivere, A.; Delaney, J.K.; Dooley, K.A.; De Meyer, S.; Vanmeert, F.; Gonzalez, V.; Janssens, K.; Leonhardt, E.; Haswell, R.; de Groot, S.; D'Imporzano, P.; Davies, G.R.
Title Beauty is skin deep : the skin tones of Vermeer's Girl with a Pearl Earring Type A1 Journal article
Year 2019 Publication Heritage science Abbreviated Journal
Volume 7 Issue 1 Pages 102
Keywords A1 Journal article; Art; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Abstract The soft modelling of the skin tones in Vermeer's Girl with a Pearl Earring (Mauritshuis) has been remarked upon by art historians, and is their main argument to date this painting to c. 1665. This paper describes the materials and techniques Vermeer used to accomplish the smooth flesh tones and facial features of the Girl, which were investigated as part of the 2018 Girl in the Spotlight research project. It combines macroscopic X-ray fluorescence imaging (MA-XRF), reflectance imaging spectroscopy (RIS), and 3D digital microscopy. Vermeer built up the face, beginning with distinct areas of light and dark. He then smoothly blended the final layers to create almost seamless transitions. The combination of advanced imaging techniques highlighted that Vermeer built the soft contour around her face by leaving a 'gap' between the background and the skin. It also revealed details that were otherwise not visible with the naked eye, such as the eyelashes. Macroscopic imaging was complemented by the study of paint cross-sections using: light microscopy, SEM-EDX, FIB-STEM, synchrotron radiation mu-XRPD and FTIR-ATR. Vermeer intentionally used different qualities or grades of lead white in the flesh paints, showing different hydrocerussite/cerussite ratios and particle sizes. Lead isotope analysis showed that the geographic source of lead, from which the different types of lead white were manufactured, was the same: the region of Peak District of Derbyshire, UK. Finally, cross-section analysis identified the formation of new lead species in the paints: lead soaps and palmierite (K2Pb(SO4)(2)), associated with the red lake.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000516736100001 Publication Date 2019-12-16
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN (up) 2050-7445 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor Times cited Open Access
Notes Approved no
Call Number UA @ admin @ c:irua:167549 Serial 7552
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Author Martins, A.; Coddington, J.; van der Snickt, G.; van Driel, B.; McGlinchey, C.; Dahlberg, D.; Janssens, K.; Dik, J.
Title Jackson Pollock's Number 1A, 1948 : a non-invasive study using macro-x-ray fluorescence mapping (MA-XRF) and multivariate curve resolution-alternating least squares (MCR-ALS) analysis Type A1 Journal article
Year 2016 Publication Heritage science Abbreviated Journal
Volume 4 Issue Pages 33
Keywords A1 Journal article; Art; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation)
Abstract Jackson Pollock's Number 1A, 1948 painting was investigated using in situ scanning macro-x-ray fluorescence mapping (MA-XRF) to help characterize the artist's materials and his creative process. A multivariate curve resolution-alternating least squares (MCR-ALS) approach was used to examine the hyperspectral data and obtain distribution maps and signature spectra for the paints he used. The composition of the paints was elucidated based on the chemical elements identified in the signature spectra and a tentative list of pigments, fillers and other additives is proposed for eleven different paints and for the canvas. The paint distribution maps were used to virtually reconstruct the artist process and document the sequence and manner in which Pollock applied the different paints, using deliberate and specific gestures.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000386395100001 Publication Date 2016-09-07
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN (up) 2050-7445 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor Times cited Open Access
Notes Approved no
Call Number UA @ admin @ c:irua:138172 Serial 8134
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Author Al-Emam, E.; Motawea, A.G.; Caen, J.; Janssens, K.
Title Soot removal from ancient Egyptian complex painted surfaces using a double network gel : empirical tests on the ceiling of the sanctuary of Osiris in the temple of Seti I-Abydos Type A1 Journal article
Year 2021 Publication Heritage science Abbreviated Journal
Volume 9 Issue 1 Pages 1-10
Keywords A1 Journal article; Art; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Antwerp Cultural Heritage Sciences (ARCHES)
Abstract In this study, we evaluated the ease of removal of soot layers from ancient wall paintings by employing double network gels as a controllable and safe cleaning method. The ceiling of the temple of Seti I (Abydos, Egypt) is covered with thick layers of soot; this is especially the case in the sanctuary of Osiris. These layers may have been accumulated during the occupation of the temple by Christians, fleeing the Romans in the first centuries A.D. Soot particulates are one of the most common deposits to be removed during conservation-restoration activities of ancient Egyptian wall paintings. They usually mask the painted reliefs and reduce the permeability of the painted surface. A Polyvinyl alcohol-borax/agarose (PVA-B/AG) double network gel was selected for this task since its properties were expected to be compatible with the cleaning treatment requirements. The gel is characterized by its flexibility, permitting to take the shape of the reliefs, while also having self-healing properties, featuring shape stability and an appropriate capacity to retain liquid. The gel was loaded with several cleaning reagents that proved to be effective for soot removal. Soot removal tests were conducted with these gel composites. The cleaned surfaces were evaluated with the naked eye, a digital microscope, and color measurements in order to select the best gel composite. The gel composite, loaded with a solution of 5% ammonia, 0.3% ammonium carbonate, and 0.3% EDTA yielded the most satisfactory results and allowed to safely remove a crust of thick soot layers from the surface. Thus, during the final phase of the study, it was used successfully to clean a larger area of the ceiling.
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Corporate Author Thesis
Publisher Place of Publication Editor
Language Wos 000604977300001 Publication Date 2021-01-04
Series Editor Series Title Abbreviated Series Title
Series Volume Series Issue Edition
ISSN (up) 2050-7445 ISBN Additional Links UA library record; WoS full record; WoS citing articles
Impact Factor Times cited Open Access OpenAccess
Notes Approved Most recent IF: NA
Call Number UA @ admin @ c:irua:174948 Serial 8557
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