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| Author | Arteaga Cardona, F.; Jain, N.; Popescu, R.; Busko, D.; Madirov, E.; Arús, B.A.; Gerthsen, D.; De Backer, A.; Bals, S.; Bruns, O.T.; Chmyrov, A.; Van Aert, S.; Richards, B.S.; Hudry, D. | ||||
| Title | Preventing cation intermixing enables 50% quantum yield in sub-15 nm short-wave infrared-emitting rare-earth based core-shell nanocrystals | Type | A1 Journal article | ||
| Year | 2023 | Publication | Nature communications | Abbreviated Journal | Nat Commun |
| Volume | 14 | Issue | 1 | Pages | 4462 |
| Keywords | A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) | ||||
| Abstract | Short-wave infrared (SWIR) fluorescence could become the new gold standard in optical imaging for biomedical applications due to important advantages such as lack of autofluorescence, weak photon absorption by blood and tissues, and reduced photon scattering coefficient. Therefore, contrary to the visible and NIR regions, tissues become translucent in the SWIR region. Nevertheless, the lack of bright and biocompatible probes is a key challenge that must be overcome to unlock the full potential of SWIR fluorescence. Although rare-earth-based core-shell nanocrystals appeared as promising SWIR probes, they suffer from limited photoluminescence quantum yield (PLQY). The lack of control over the atomic scale organization of such complex materials is one of the main barriers limiting their optical performance. Here, the growth of either homogeneous (α-NaYF<sub>4</sub>) or heterogeneous (CaF<sub>2</sub>) shell domains on optically-active α-NaYF<sub>4</sub>:Yb:Er (with and without Ce<sup>3+</sup>co-doping) core nanocrystals is reported. The atomic scale organization can be controlled by preventing cation intermixing only in heterogeneous core-shell nanocrystals with a dramatic impact on the PLQY. The latter reached 50% at 60 mW/cm<sup>2</sup>; one of the highest reported PLQY values for sub-15 nm nanocrystals. The most efficient nanocrystals were utilized for in vivo imaging above 1450 nm. | ||||
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| Language | Wos | 001037058500022 | Publication Date | 2023-07-25 | |
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| ISSN | 2041-1723 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 16.6 | Times cited | 1 | Open Access | OpenAccess |
| Notes | D.H. would like to thank Dominique Ectors (Bruker AXS GmbH, Karlsruhe, Germany) for assistance and discussion on the PXRD data and TOPAS evaluations. The authors would like to acknowledge the financial support provided by the Helmholtz Association via: i) the Professorial Recruitment Initiative Funding (B.S.R.); ii) the Research Field Energy – Program Materials and Technologies for the Energy Transition – Topic 1 Photovoltaics (F.A.C., D.B., E.M., B.S.R., D.H.). This project received funding from the European Union’s Horizon 2020 innovation programme under grant agreement 823717. This work was supported by the European Research Council (grant 770887-PICOMETRICS to S.V.A. and Grant 815128-REALNANO to S.B.). The authors acknowledge financial support from the ResearchFoundation Flanders (FWO, Belgium) through project fundings (G.0346.21 N to S.V.A. and S.B.) and a postdoctoral grant (A.D.B.). The authors (B.A.A., O.T.B. and A.C.) acknowledge funding from the Helmholtz Zentrum München, the DFG-Emmy Noether program (BR 5355/2-1) and from the CZI Deep Tissue Imaging (DTI-0000000248). The authors (O.T.B. and D.H.) would like to thank the Helmholtz Imaging (ZT-I-PF-4-038-BENIGN). | Approved | Most recent IF: 16.6; 2023 IF: 12.124 | ||
| Call Number | EMAT @ emat @c:irua:198158 | Serial | 8808 | ||
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| Author | Lobato, I.; De Backer, A.; Van Aert, S. | ||||
| Title | Real-time simulations of ADF STEM probe position-integrated scattering cross-sections for single element fcc crystals in zone axis orientation using a densely connected neural network | Type | A1 Journal article | ||
| Year | 2023 | Publication | Ultramicroscopy | Abbreviated Journal | Ultramicroscopy |
| Volume | 251 | Issue | Pages | 113769 | |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
| Abstract | Quantification of annular dark field (ADF) scanning transmission electron microscopy (STEM) images in terms of composition or thickness often relies on probe-position integrated scattering cross sections (PPISCS). In order to compare experimental PPISCS with theoretically predicted ones, expensive simulations are needed for a given specimen, zone axis orientation, and a variety of microscope settings. The computation time of such simulations can be in the order of hours using a single GPU card. ADF STEM simulations can be efficiently parallelized using multiple GPUs, as the calculation of each pixel is independent of other pixels. However, most research groups do not have the necessary hardware, and, in the best-case scenario, the simulation time will only be reduced proportionally to the number of GPUs used. In this manuscript, we use a learning approach and present a densely connected neural network that is able to perform real-time ADF STEM PPISCS predictions as a function of atomic column thickness for most common face-centered cubic (fcc) crystals (i.e., Al, Cu, Pd, Ag, Pt, Au and Pb) along [100] and [111] zone axis orientations, root-mean-square displacements, and microscope parameters. The proposed architecture is parameter efficient and yields accurate predictions for the PPISCS values for a wide range of input parameters that are commonly used for aberration-corrected transmission electron microscopes. |
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| Language | Wos | 001011617200001 | Publication Date | 2023-06-01 | |
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| ISSN | 0304-3991 | ISBN | Additional Links | UA library record; WoS full record | |
| Impact Factor | 2.2 | Times cited | Open Access | OpenAccess | |
| Notes | This work was supported by the European Research Council (Grant 770887 PICOMETRICS to S. Van Aert). The authors acknowledge financial support from the Research Foundation Flanders (FWO, Belgium) through project fundings (G034621N and G0A7723N) and a postdoctoral grant to A. De Backer. S. Van Aert acknowledges funding from the University of Antwerp Research fund (BOF), Belgium. | Approved | Most recent IF: 2.2; 2023 IF: 2.843 | ||
| Call Number | EMAT @ emat @c:irua:197275 | Serial | 8812 | ||
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| Author | Şentürk, DG.; Yu, CP.; De Backer, A.; Van Aert, S. | ||||
| Title | Atom counting from a combination of two ADF STEM images | Type | A1 Journal article | ||
| Year | 2024 | Publication | Ultramicroscopy | Abbreviated Journal | Ultramicroscopy |
| Volume | 255 | Issue | Pages | 113859 | |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
| Abstract | To understand the structure–property relationship of nanostructures, reliably quantifying parameters, such as the number of atoms along the projection direction, is important. Advanced statistical methodologies have made it possible to count the number of atoms for monotype crystalline nanoparticles from a single ADF STEM image. Recent developments enable one to simultaneously acquire multiple ADF STEM images. Here, we present an extended statistics-based method for atom counting from a combination of multiple statistically independent ADF STEM images reconstructed from non-overlapping annular detector collection regions which improves the accuracy and allows one to retrieve precise atom-counts, especially for images acquired with low electron doses and multiple element structures. | ||||
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| Language | Wos | 001089064200001 | Publication Date | 2023-09-23 | |
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| ISSN | 0304-3991 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 2.2 | Times cited | Open Access | OpenAccess | |
| Notes | This work was supported by the European Research Council (Grant 770887 PICOMETRICS to S. Van Aert). The authors acknowledge financial support from the Research Foundation Flanders (FWO, Belgium) through project fundings (G034621N, G0A7723N, and EOS 40007495) and a postdoctoral grant to A. De Backer. S. Van Aert acknowledges funding from the University of Antwerp Research fund (BOF). | Approved | Most recent IF: 2.2; 2024 IF: 2.843 | ||
| Call Number | EMAT @ emat @c:irua:201008 | Serial | 8964 | ||
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| Author | Şentürk, D.G.; De Backer, A.; Van Aert, S. | ||||
| Title | Element specific atom counting for heterogeneous nanostructures: Combining multiple ADF STEM images for simultaneous thickness and composition determination | Type | A1 Journal Article | ||
| Year | 2024 | Publication | Ultramicroscopy | Abbreviated Journal | Ultramicroscopy |
| Volume | 259 | Issue | Pages | 113941 | |
| Keywords | A1 Journal Article; Electron Microscopy for Materials Science (EMAT) ; | ||||
| Abstract | In this paper, a methodology is presented to count the number of atoms in heterogeneous nanoparticles based on the combination of multiple annular dark field scanning transmission electron microscopy (ADF STEM) images. The different non-overlapping annular detector collection regions are selected based on the principles of optimal statistical experiment design for the atom-counting problem. To count the number of atoms, the total intensities of scattered electrons for each atomic column, the so-called scattering cross-sections, are simultaneously compared with simulated library values for the different detector regions by minimising the squared differences. The performance of the method is evaluated for simulated Ni@Pt and Au@Ag core-shell nanoparticles. Our approach turns out to be a dose efficient alternative for the investigation of beam-sensitive heterogeneous materials as compared to the combination of ADF STEM and energy dispersive X-ray spectroscopy. | ||||
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| Language | Wos | Publication Date | 2024-02-19 | ||
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| ISSN | 0304-3991 | ISBN | Additional Links | UA library record | |
| Impact Factor | 2.2 | Times cited | Open Access | OpenAccess | |
| Notes | This work was supported by the European Research Council (Grant 770887 PICOMETRICS to S. Van Aert). The authors acknowledge financial support from the Research Foundation Flanders (FWO, Belgium) through project fundings (G.0346.21N, GOA7723N, and EOS 40007495) and a postdoctoral grant to A. De Backer. S. Van Aert acknowledges funding from the University of Antwerp Research fund (BOF). | Approved | Most recent IF: 2.2; 2024 IF: 2.843 | ||
| Call Number | EMAT @ emat @c:irua:204353 | Serial | 8996 | ||
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| Author | van den Broek, W.; Verbeeck, J.; de Backer, S.; Scheunders, P.; Schryvers, D. | ||||
| Title | Acquisition of the EELS data cube by tomographic reconstruction | Type | A1 Journal article | ||
| Year | 2006 | Publication | Ultramicroscopy | Abbreviated Journal | Ultramicroscopy |
| Volume | 106 | Issue | 4/5 | Pages | 269-276 |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT); Vision lab | ||||
| Abstract | Energy filtered TEM, EFTEM, provides three-dimensional data, two spatial and one spectral dimension. We propose to acquire these data by measuring a series of images with a defocused energy filter. It will be shown that each image is a projection of the data on the detector and that reconstruction of the data out of a sufficient number of such projections using a tomographic reconstruction algorithm is possible. This technique uses only a fraction of the electron dose an energy filtered series (EFS) needs for the same spectral and spatial resolution and the same mean signal-to-noise ratio. (c) 2005 Elsevier B.V. All rights reserved. | ||||
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Amsterdam | Editor | ||
| Language | Wos | 000236042300003 | Publication Date | 2005-11-30 | |
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| ISSN | 0304-3991; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 2.843 | Times cited | 6 | Open Access | |
| Notes | Approved | Most recent IF: 2.843; 2006 IF: 1.706 | |||
| Call Number | UA @ lucian @ c:irua:56910UA @ admin @ c:irua:56910 | Serial | 55 | ||
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| Author | de Backer, A.; Martinez, G.T.; Rosenauer, A.; Van Aert, S. | ||||
| Title | Atom counting in HAADF STEM using a statistical model-based approach : methodology, possibilities, and inherent limitations | Type | A1 Journal article | ||
| Year | 2013 | Publication | Ultramicroscopy | Abbreviated Journal | Ultramicroscopy |
| Volume | 134 | Issue | Pages | 23-33 | |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
| Abstract | In the present paper, a statistical model-based method to count the number of atoms of monotype crystalline nanostructures from high resolution high-angle annular dark-field (HAADF) scanning transmission electron microscopy (STEM) images is discussed in detail together with a thorough study on the possibilities and inherent limitations. In order to count the number of atoms, it is assumed that the total scattered intensity scales with the number of atoms per atom column. These intensities are quantitatively determined using model-based statistical parameter estimation theory. The distribution describing the probability that intensity values are generated by atomic columns containing a specific number of atoms is inferred on the basis of the experimental scattered intensities. Finally, the number of atoms per atom column is quantified using this estimated probability distribution. The number of atom columns available in the observed STEM image, the number of components in the estimated probability distribution, the width of the components of the probability distribution, and the typical shape of a criterion to assess the number of components in the probability distribution directly affect the accuracy and precision with which the number of atoms in a particular atom column can be estimated. It is shown that single atom sensitivity is feasible taking the latter aspects into consideration. | ||||
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Amsterdam | Editor | ||
| Language | Wos | 000324474900005 | Publication Date | 2013-05-17 | |
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| ISSN | 0304-3991; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 2.843 | Times cited | 48 | Open Access | |
| Notes | FWO; Esteem2; FP 2007-2013; esteem2_jra2 | Approved | Most recent IF: 2.843; 2013 IF: 2.745 | ||
| Call Number | UA @ lucian @ c:irua:109916 | Serial | 162 | ||
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| Author | de Backer, A.; Martinez, G.T.; MacArthur, K.E.; Jones, L.; Béché, A.; Nellist, P.D.; Van Aert, S. | ||||
| Title | Dose limited reliability of quantitative annular dark field scanning transmission electron microscopy for nano-particle atom-counting | Type | A1 Journal article | ||
| Year | 2015 | Publication | Ultramicroscopy | Abbreviated Journal | Ultramicroscopy |
| Volume | 151 | Issue | 151 | Pages | 56-61 |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
| Abstract | Quantitative annular dark field scanning transmission electron microscopy (ADF STEM) has become a powerful technique to characterise nano-particles on an atomic scale. Because of their limited size and beam sensitivity, the atomic structure of such particles may become extremely challenging to determine. Therefore keeping the incoming electron dose to a minimum is important. However, this may reduce the reliability of quantitative ADF STEM which will here be demonstrated for nano-particle atom-counting. Based on experimental ADF STEM images of a real industrial catalyst, we discuss the limits for counting the number of atoms in a projected atomic column with single atom sensitivity. We diagnose these limits by combining a thorough statistical method and detailed image simulations. | ||||
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Amsterdam | Editor | ||
| Language | Wos | 000351237800008 | Publication Date | 2014-12-03 | |
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| ISSN | 0304-3991; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 2.843 | Times cited | 29 | Open Access | |
| Notes | 312483 Esteem2; 278510 Vortex; Fwo G039311; G006410; G037413; esteem2ta; ECASJO; | Approved | Most recent IF: 2.843; 2015 IF: 2.436 | ||
| Call Number | c:irua:123927 c:irua:123927 | Serial | 753 | ||
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| Author | den Dekker, A.J.; Gonnissen, J.; de Backer, A.; Sijbers, J.; Van Aert, S. | ||||
| Title | Estimation of unknown structure parameters from high-resolution (S)TEM images : what are the limits? | Type | A1 Journal article | ||
| Year | 2013 | Publication | Ultramicroscopy | Abbreviated Journal | Ultramicroscopy |
| Volume | 134 | Issue | Pages | 34-43 | |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT); Vision lab | ||||
| Abstract | Statistical parameter estimation theory is proposed as a quantitative method to measure unknown structure parameters from electron microscopy images. Images are then purely considered as data planes from which structure parameters have to be determined as accurately and precisely as possible using a parametric statistical model of the observations. For this purpose, an efficient algorithm is proposed for the estimation of atomic column positions and intensities from high angle annular dark field (HAADF) scanning transmission electron microscopy (STEM) images. Furthermore, the so-called CramérRao lower bound (CRLB) is reviewed to determine the limits to the precision with which continuous parameters such as atomic column positions and intensities can be estimated. Since this lower bound can only be derived for continuous parameters, alternative measures using the principles of detection theory are introduced for problems concerning the estimation of discrete parameters such as atomic numbers. An experimental case study is presented to show the practical use of these measures for the optimization of the experiment design if the purpose is to decide between the presence of specific atom types using STEM images. | ||||
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Amsterdam | Editor | ||
| Language | Wos | 000324474900006 | Publication Date | 2013-06-01 | |
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| ISSN | 0304-3991; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 2.843 | Times cited | 31 | Open Access | |
| Notes | FWO; FP 2007-2013; Esteem2; esteem2_jra2 | Approved | Most recent IF: 2.843; 2013 IF: 2.745 | ||
| Call Number | UA @ lucian @ c:irua:109240 | Serial | 1083 | ||
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| Author | Van Holsbeke, C.; Vos, W.; van Hoorenbeeck, K.; Boudewyns, A.; Salgado, R.; Verdonck, P.R.; Ramet, J.; de Backer, J.; De Backer, W.; Verhulst, S.L. | ||||
| Title | Functional respiratory imaging as a tool to assess upper airway patency in children with obstructive sleep apnea | Type | A1 Journal article | ||
| Year | 2013 | Publication | Sleep Medicine | Abbreviated Journal | Sleep Med |
| Volume | 14 | Issue | 5 | Pages | 433-439 |
| Keywords | A1 Journal article; Condensed Matter Theory (CMT); Laboratory Experimental Medicine and Pediatrics (LEMP) | ||||
| Abstract | Objective: We aim to investigate if anatomical and functional properties of the upper airway using computerized 3D models derived from computed tomography (CT) scans better predict obstructive sleep apnea (OSA) severity than standard clinical markers. Methods: Consecutive children with suspected OSA underwent polysomnography, clinical assessment of upper airway patency, and a CT scan while awake. A three-dimensional (3D) reconstruction of the pharyngeal airway was built from these images, and computational fluid dynamics modeling of low inspiratory flow was performed using open-source software. Results: Thirty-three children were included (23 boys; mean age, was 6.0 +/- 3.2 y). OSA was diagnosed in 23 patients. Children with OSA had a significantly lower volume of the overlap region between tonsils and the adenoids (median volume, 1408 mm compared to 2173 mm; p = 0.04), a lower mean cross-sectional area at this location (median volume, 69.3 mm(2) compared to 114.3 mm(2); p = 0.04), and a lower minimal cross-sectional area (median volume, 17.9 mm(2) compared to 25.9 mm(2); p = 0.05). Various significant correlations were found between several imaging parameters and the severity of OSA, most pronounced for upper airway conductance (r = -0.46) (p < 0.01) for correlation between upper airway conductance and the apnea-hypopnea index. No differences or significant correlations were observed with clinical parameters of upper airway patency. Preliminary data after treatment showed that none of the patients with residual OSA had their smallest cross-sectional area located in segment 3, and this frequency was significantly lower than in their peers whose sleep study normalized (64%; p = 0.05). Conclusion: Functional imaging parameters are highly correlated with OSA severity and are a more powerful correlate than clinical scores of upper airway patency. Preliminary data also showed that we could identify differences in the upper airway of those subjects who did not benefit from a local upper airway treatment. (c) 2013 Elsevier B.V. All rights reserved. | ||||
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Amsterdam | Editor | ||
| Language | Wos | 000318612100009 | Publication Date | 2013-03-07 | |
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| ISSN | 1389-9457; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 3.391 | Times cited | 18 | Open Access | |
| Notes | ; ; | Approved | Most recent IF: 3.391; 2013 IF: 3.100 | ||
| Call Number | UA @ lucian @ c:irua:109015 | Serial | 1302 | ||
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| Author | de Backer, A.; Van Aert, S.; van Dyck, D. | ||||
| Title | High precision measurements of atom column positions using model-based exit wave reconstruction | Type | A1 Journal article | ||
| Year | 2011 | Publication | Ultramicroscopy | Abbreviated Journal | Ultramicroscopy |
| Volume | 111 | Issue | 9/10 | Pages | 1475-1482 |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT); Vision lab | ||||
| Abstract | In this paper, it has been investigated how to measure atom column positions as accurately and precisely as possible using a focal series of images. In theory, it is expected that the precision would considerably improve using a maximum likelihood estimator based on the full series of focal images. As such, the theoretical lower bound on the variances of the unknown atom column positions can be attained. However, this approach is numerically demanding. Therefore, maximum likelihood estimation has been compared with the results obtained by fitting a model to a reconstructed exit wave rather than to the full series of focal images. Hence, a real space model-based exit wave reconstruction technique based on the channelling theory is introduced. Simulations show that the reconstructed complex exit wave contains the same amount of information concerning the atom column positions as the full series of focal images. Only for thin samples, which act as weak phase objects, this information can be retrieved from the phase of the reconstructed complex exit wave. | ||||
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Amsterdam | Editor | ||
| Language | Wos | 000300461200004 | Publication Date | 2011-07-28 | |
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| ISSN | 0304-3991; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 2.843 | Times cited | 8 | Open Access | |
| Notes | Fwo | Approved | Most recent IF: 2.843; 2011 IF: 2.471 | ||
| Call Number | UA @ lucian @ c:irua:91879 | Serial | 1438 | ||
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| Author | de Backer, A.; De wael, A.; Gonnissen, J.; Van Aert, S. | ||||
| Title | Optimal experimental design for nano-particle atom-counting from high-resolution STEM images | Type | A1 Journal article | ||
| Year | 2015 | Publication | Ultramicroscopy | Abbreviated Journal | Ultramicroscopy |
| Volume | 151 | Issue | 151 | Pages | 46-55 |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
| Abstract | In the present paper, the principles of detection theory are used to quantify the probability of error for atom-counting from high resolution scanning transmission electron microscopy (HR STEM) images. Binary and multiple hypothesis testing have been investigated in order to determine the limits to the precision with which the number of atoms in a projected atomic column can be estimated. The probability of error has been calculated when using STEM images, scattering cross-sections or peak intensities as a criterion to count atoms. Based on this analysis, we conclude that scattering cross-sections perform almost equally well as images and perform better than peak intensities. Furthermore, the optimal STEM detector design can be derived for atom-counting using the expression for the probability of error. We show that for very thin objects LAADF is optimal and that for thicker objects the optimal inner detector angle increases. | ||||
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Amsterdam | Editor | ||
| Language | Wos | 000351237800007 | Publication Date | 2014-11-11 | |
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| ISSN | 0304-3991; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 2.843 | Times cited | 24 | Open Access | |
| Notes | 312483 Esteem2; Fwo G039311; G037413; esteem2_jra2 | Approved | Most recent IF: 2.843; 2015 IF: 2.436 | ||
| Call Number | c:irua:123926 c:irua:123926 | Serial | 2481 | ||
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| Author | Martinez, G.T.; Rosenauer, A.; de Backer, A.; Verbeeck, J.; Van Aert, S. | ||||
| Title | Quantitative composition determination at the atomic level using model-based high-angle annular dark field scanning transmission electron microscopy | Type | A1 Journal article | ||
| Year | 2014 | Publication | Ultramicroscopy | Abbreviated Journal | Ultramicroscopy |
| Volume | 137 | Issue | Pages | 12-19 | |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
| Abstract | High angle annular dark field scanning transmission electron microscopy (HAADF STEM) images provide sample information which is sensitive to the chemical composition. The image intensities indeed scale with the mean atomic number Z. To some extent, chemically different atomic column types can therefore be visually distinguished. However, in order to quantify the atomic column composition with high accuracy and precision, model-based methods are necessary. Therefore, an empirical incoherent parametric imaging model can be used of which the unknown parameters are determined using statistical parameter estimation theory (Van Aert et al., 2009, [1]). In this paper, it will be shown how this method can be combined with frozen lattice multislice simulations in order to evolve from a relative toward an absolute quantification of the composition of single atomic columns with mixed atom types. Furthermore, the validity of the model assumptions are explored and discussed. | ||||
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Amsterdam | Editor | ||
| Language | Wos | 000331092200003 | Publication Date | 2013-11-09 | |
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| ISSN | 0304-3991; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 2.843 | Times cited | 74 | Open Access | |
| Notes | FWO; FP7; ERC Countatoms; ESTEEM2; esteem2_ta | Approved | Most recent IF: 2.843; 2014 IF: 2.436 | ||
| Call Number | UA @ lucian @ c:irua:111579UA @ admin @ c:irua:111579 | Serial | 2749 | ||
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| Author | Martinez, G.T.; Jones, L.; de Backer, A.; Béché, A.; Verbeeck, J.; Van Aert, S.; Nellist, P.D. | ||||
| Title | Quantitative STEM normalisation : the importance of the electron flux | Type | A1 Journal article | ||
| Year | 2015 | Publication | Ultramicroscopy | Abbreviated Journal | Ultramicroscopy |
| Volume | 159 | Issue | 159 | Pages | 46-58 |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
| Abstract | Annular dark-field (ADF) scanning transmission electron microscopy (STEM) has become widely used in quantitative studies based on the opportunity to directly compare experimental and simulated images. This comparison merely requires the experimental data to be normalised and expressed in units of fractional beam-current. However, inhomogeneities in the response of electron detectors can complicate this normalisation. The quantification procedure becomes both experiment and instrument specific, requiring new simulations for the particular response of each instrument's detector, and for every camera-length used. This not only impedes the comparison between different instruments and research groups, but can also be computationally very time consuming. Furthermore, not all image simulation methods allow for the inclusion of an inhomogeneous detector response. In this work, we propose an alternative method for normalising experimental data in order to compare these with simulations that consider a homogeneous detector response. To achieve this, we determine the electron flux distribution reaching the detector by means of a camera-length series or a so-called atomic column cross-section averaged convergent beam electron diffraction (XSACBED) pattern. The result is then used to determine the relative weighting of the detector response. Here we show that the results obtained by this new electron flux weighted (EFW) method are comparable to the currently used method, while considerably simplifying the needed simulation libraries. The proposed method also allows one to obtain a metric that describes the quality of the detector response in comparison with the ideal detector response. | ||||
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| Corporate Author | Thesis | ||||
| Publisher | Place of Publication |
Amsterdam | Editor | ||
| Language | Wos | 000366220000006 | Publication Date | 2015-08-01 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 0304-3991; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 2.843 | Times cited | 27 | Open Access | |
| Notes | 246791 Countatoms; 278510 Vortex; 312483 Esteem2; Fwo G036815; G036915; G037413; G004413; esteem2ta ECASJO; | Approved | Most recent IF: 2.843; 2015 IF: 2.436 | ||
| Call Number | c:irua:127293 c:irua:127293UA @ admin @ c:irua:127293 | Serial | 2762 | ||
| Permanent link to this record | |||||
| Author | van den Broek, W.; Verbeeck, J.; Schryvers, D.; de Backer, S.; Scheunders, P. | ||||
| Title | Tomographic spectroscopic imaging; an experimental proof of concept | Type | A1 Journal article | ||
| Year | 2009 | Publication | Ultramicroscopy | Abbreviated Journal | Ultramicroscopy |
| Volume | 109 | Issue | 4 | Pages | 296-303 |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT); Vision lab | ||||
| Abstract | Recording the electron energy loss spectroscopy data cube with a series of energy filtered images is a dose inefficient process because the energy slit blocks most of the electrons. When recording the data cube by scanning an electron probe over the sample, perfect dose efficiency is attained; but due to the low current in nanoprobes, this often is slower, with a smaller field of view. In W. Van den Broek et al. [Ultramicroscopy, 106 (2006) 269], we proposed a new method to record the data cube, which is more dose efficient than an energy filtered series. It produces a set of projections of the data cube and then tomographically reconstructs it. In this article, we demonstrate these projections in practice, we present a simple geometrical model that allows for quantification of the projection angles and we present the first successful experimental reconstruction, all on a standard post-column instrument. | ||||
| Address | |||||
| Corporate Author | Thesis | ||||
| Publisher | Place of Publication |
Amsterdam | Editor | ||
| Language | Wos | 000265345400003 | Publication Date | 2008-12-10 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 0304-3991; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 2.843 | Times cited | 1 | Open Access | |
| Notes | Esteem 026019 | Approved | Most recent IF: 2.843; 2009 IF: 2.067 | ||
| Call Number | UA @ lucian @ c:irua:77271 | Serial | 3671 | ||
| Permanent link to this record | |||||
| Author | de Backer, J.; Vanderveken, O.; Vos, W.; Devolder, A.; Verhulst, S.; Verbraecken, J. | ||||
| Title | Functional imaging to predict treatment success of mandibular advancement devices in sleep-disordered breathing | Type | H3 Book chapter | ||
| Year | 2008 | Publication | Abbreviated Journal | ||
| Volume | Issue | Pages | 141-155 | ||
| Keywords | H3 Book chapter; Condensed Matter Theory (CMT); Laboratory Experimental Medicine and Pediatrics (LEMP); Translational Neurosciences (TNW) | ||||
| Abstract | |||||
| Address | |||||
| Corporate Author | Thesis | ||||
| Publisher | Place of Publication |
Antwerpen | Editor | ||
| Language | Wos | Publication Date | 0000-00-00 | ||
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | ISBN | Additional Links | UA library record | ||
| Impact Factor | Times cited | Open Access | |||
| Notes | Approved | Most recent IF: NA | |||
| Call Number | UA @ lucian @ c:irua:72885 | Serial | 1298 | ||
| Permanent link to this record | |||||
| Author | de Backer, A. | ||||
| Title | Quantitative atomic resolution electron microscopy using advanced statistical techniques | Type | Doctoral thesis | ||
| Year | 2015 | Publication | Abbreviated Journal | ||
| Volume | Issue | Pages | |||
| Keywords | Doctoral thesis; Electron microscopy for materials research (EMAT) | ||||
| Abstract | |||||
| Address | |||||
| Corporate Author | Thesis | ||||
| Publisher | Place of Publication |
Antwerpen | Editor | ||
| Language | Wos | Publication Date | 0000-00-00 | ||
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | ISBN | Additional Links | UA library record | ||
| Impact Factor | Times cited | Open Access | |||
| Notes | Approved | Most recent IF: NA | |||
| Call Number | UA @ lucian @ c:irua:125636 | Serial | 2747 | ||
| Permanent link to this record | |||||
| Author | Vos, W.; de Backer, J.; Poli, G.; De Volder, A.; Ghys, L.; Van Holsbeke, C.; Vinchurkar, S.; De Backer, L.; de Backer, W. | ||||
| Title | Novel functional imaging of changes in small airways of patients treated with extrafine beclomethasone/formoterol | Type | A1 Journal article | ||
| Year | 2013 | Publication | Respiration | Abbreviated Journal | Respiration |
| Volume | 86 | Issue | 5 | Pages | 393-401 |
| Keywords | A1 Journal article; Biophysics and Biomedical Physics; Condensed Matter Theory (CMT); Laboratory Experimental Medicine and Pediatrics (LEMP) | ||||
| Abstract | Background: Inhaled formulations using extrafine particles of long-acting beta(2)-agonists and corticosteroids were developed to optimize asthma treatment. Findings that these combinations reach and treat smaller airways more effectively are predominantly based on general non-specific outcomes with little information on regional characteristics. Objectives: This study aims to assess long-term effects of extrafine beclomethasone/formoterol on small airways of asthmatic patients using novel functional imaging methods. Methods: Twenty-four stable asthma patients were subdivided into three groups (steroid naive, n = 7; partially controlled, n = 6; well controlled, n = 11). Current treatment was switched to a fixed combination of extrafine beclomethasone/formoterol (Foster (R); Chiesi Pharmaceuticals, Parma, Italy). Patients underwent lung function evaluation and thorax high-resolution computerized tomography (HRCT) scan. Local airway resistance was obtained from computational fluid dynamics (CFD). Results: After 6 months, the entire population showed improvement in pre-bronchodilation imaging parameters, including small airway volume (p = 0.0007), resistance (p = 0.011), and asthma control score (p = 0.016). Changes in small airway volume correlated with changes in asthma control score (p = 0.004). Forced expiratory volume in 1 s (p = 0.044) and exhaled nitric oxide (p = 0.040) also improved. Functional imaging provided more detail and clinical relevance compared to lung function tests, especially in the well-controlled group where only functional imaging parameters showed significant improvement, while the correlation with asthma control score remained. Conclusions: Extrafine beclomethasone/formoterol results in a significant reduction of small airway obstruction, detectable by functional imaging (HRCT/CFD). Changes in imaging parameters correlated significantly with clinically relevant improvements. This indicates that functional imaging is a useful tool for sensitive assessment of changes in the respiratory system after asthma treatment. Copyright (C) 2013 S. Karger AG, Basel | ||||
| Address | |||||
| Corporate Author | Thesis | ||||
| Publisher | Place of Publication |
Basel | Editor | ||
| Language | Wos | 000329046200006 | Publication Date | 2013-04-12 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 1423-0356;0025-7931; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 2.772 | Times cited | 30 | Open Access | |
| Notes | ; ; | Approved | Most recent IF: 2.772; 2013 IF: 2.924 | ||
| Call Number | UA @ lucian @ c:irua:113762 | Serial | 2376 | ||
| Permanent link to this record | |||||
| Author | de Backer, A.; De wael, A.; Gonnissen, J.; Martinez, G.T.; Béché, A.; MacArthur, K.E.; Jones, L.; Nellist, P.D.; Van Aert, S. | ||||
| Title | Quantitative annular dark field scanning transmission electron microscopy for nanoparticle atom-counting : what are the limits? | Type | A1 Journal article | ||
| Year | 2015 | Publication | Journal of physics : conference series | Abbreviated Journal | |
| Volume | 644 | Issue | Pages | 012034-4 | |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
| Abstract | Quantitative atomic resolution annular dark field scanning transmission electron microscopy (ADF STEM) has become a powerful technique for nanoparticle atom-counting. However, a lot of nanoparticles provide a severe characterisation challenge because of their limited size and beam sensitivity. Therefore, quantitative ADF STEM may greatly benefit from statistical detection theory in order to optimise the instrumental microscope settings such that the incoming electron dose can be kept as low as possible whilst still retaining single-atom precision. The principles of detection theory are used to quantify the probability of error for atom-counting. This enables us to decide between different image performance measures and to optimise the experimental detector settings for atom-counting in ADF STEM in an objective manner. To demonstrate this, ADF STEM imaging of an industrial catalyst has been conducted using the near-optimal detector settings. For this experiment, we discussed the limits for atomcounting diagnosed by combining a thorough statistical method and detailed image simulations. | ||||
| Address | |||||
| Corporate Author | Thesis | ||||
| Publisher | Place of Publication |
Bristol | Editor | ||
| Language | Wos | Publication Date | |||
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 1742-6588; 1742-6596 | ISBN | Additional Links | UA library record | |
| Impact Factor | Times cited | Open Access | |||
| Notes | Approved | Most recent IF: NA | |||
| Call Number | UA @ lucian @ c:irua:129198 | Serial | 4506 | ||
| Permanent link to this record | |||||
| Author | de Backer, W.; Vos, W.; Van Holsbeke, C.; Vinchurkar, S.; Claes, R.; Hufkens, A.; Parizel, P.M.; Bedert, L.; de Backer, J. | ||||
| Title | The effect of roflumilast in addition to LABA/LAMA/ICS treatment in COPD patients | Type | L1 Letter to the editor | ||
| Year | 2014 | Publication | European Respiratory Journal | Abbreviated Journal | Eur Respir J |
| Volume | 44 | Issue | 2 | Pages | 527-529 |
| Keywords | L1 Letter to the editor; Biophysics and Biomedical Physics; Condensed Matter Theory (CMT); Antwerp Surgical Training, Anatomy and Research Centre (ASTARC); Laboratory Experimental Medicine and Pediatrics (LEMP) | ||||
| Abstract | |||||
| Address | |||||
| Corporate Author | Thesis | ||||
| Publisher | Place of Publication |
Copenhagen | Editor | ||
| Language | Wos | 000340017300029 | Publication Date | 2014-05-03 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 0903-1936;1399-3003; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 10.569 | Times cited | 26 | Open Access | |
| Notes | ; ; | Approved | Most recent IF: 10.569; 2014 IF: 7.636 | ||
| Call Number | UA @ lucian @ c:irua:117335 | Serial | 832 | ||
| Permanent link to this record | |||||
| Author | De Backer, L.A.; Vos, W.; de Backer, J.; Van Holsbeke, C.; Vinchurkar, S.; de Backer, W. | ||||
| Title | The acute effect of budesonide/formoterol in COPD : a multi-slice computed tomography and lung function study | Type | A1 Journal article | ||
| Year | 2012 | Publication | European Respiratory Journal | Abbreviated Journal | Eur Respir J |
| Volume | 40 | Issue | 2 | Pages | 298-305 |
| Keywords | A1 Journal article; Biophysics and Biomedical Physics; Condensed Matter Theory (CMT); Laboratory Experimental Medicine and Pediatrics (LEMP) | ||||
| Abstract | The Global Initiative for Chronic Obstructive Lung Disease (GOLD) classification of chronic obstructive pulmonary disease (COPD) does not always match with other clinical disease descriptors such as exacerbation frequency and quality of life, indicating that forced expiratory volume in 1 s (FEV1) is not a perfect descriptor of the disease. The aim of this study was to find out whether changes in airway geometry after inhalation of the most commonly used inhalation therapy in severe COPD can more adequately be described with an image-based approach than with spirometry. 10 COPD GOLD stage III patients were assessed in a double-blind crossover study. Airway volumes were analysed using segmentation of multi-slice computed tomography (MSCT) images; airway resistance was determined using computational fluid dynamics (CFD). Distal airway volume significantly increased (p=0.011) in patients 4 h after receiving a budesonide/formoterol combination from 9.6+/-4.67 cm(3) to 10.14+/-4.81 cm(3). Also CFD-determined airway resistance significantly decreased (p=0.047) from 0.051+/-0.021 kPa.s.L-1 to 0.043+/- 0.019 kPa.s.L-1. None of the lung function parameters showed a significant change. Only functional residual capacity (FRC) showed a trend to decline (p=0.056). Only the image-based parameters were able to predict the visit at which the combination product was administered. This study showed that imaging is a sensitive, complementary tool to describe changes in airway structure. | ||||
| Address | |||||
| Corporate Author | Thesis | ||||
| Publisher | Place of Publication |
Copenhagen | Editor | ||
| Language | Wos | 000307291700006 | Publication Date | 2011-12-20 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 0903-1936;1399-3003; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 10.569 | Times cited | 37 | Open Access | |
| Notes | ; ; | Approved | Most recent IF: 10.569; 2012 IF: 6.355 | ||
| Call Number | UA @ lucian @ c:irua:101113 | Serial | 3568 | ||
| Permanent link to this record | |||||
| Author | Van Holsbeke, C.S.; Leemans, G.; Vos, W.G.; de Backer, J.W.; Vinchurkar, S.C.; Geldof, M.; Verdonck, P.R.; Parizel, P.M.; van Schil, P.E.; de Backer, W.A. | ||||
| Title | Functional Respiratory Imaging as a tool to personalize respiratory treatment in subjects with unilateral diaphragmatic paralysis | Type | A1 Journal article | ||
| Year | 2013 | Publication | Respiratory care | Abbreviated Journal | Resp Care |
| Volume | Issue | Pages | 1-20 | ||
| Keywords | A1 Journal article; Condensed Matter Theory (CMT); Antwerp Surgical Training, Anatomy and Research Centre (ASTARC); Laboratory Experimental Medicine and Pediatrics (LEMP) | ||||
| Abstract | In two subjects with a unilateral diaphragmatic paralysis and complaints of dyspnea, a completely different treatment approach was chosen despite similar anatomical and physiological abnormalities. These decisions were supported by the results generated by Functional Respiratory Imaging (FRI). FRI was able to generate functional information with respect to lobar ventilation and local drug deposition. In one subject, it was found that some lobes were poorly ventilated and drug deposition simulation showed that some regions were undertreated. This subject underwent a diaphragm plication to restore the ventilation. In the other subject, it was found that all lobes were still ventilated. A conservative approach with regular follow-up was chosen to wait for spontaneous recovery of the diaphragmatic function. Both subjects improved subjectively and objectively. These cases demonstrate how novel medical imaging techniques such as FRI can be used to personalize respiratory treatment in subjects with unilateral diaphragmatic paralysis. | ||||
| Address | |||||
| Corporate Author | Thesis | ||||
| Publisher | Place of Publication |
Dallas, Tex. | Editor | ||
| Language | Wos | 000349200100024 | Publication Date | 2013-12-11 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 0020-1324;1943-3654; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 1.733 | Times cited | 5 | Open Access | |
| Notes | ; ; | Approved | Most recent IF: 1.733; 2013 IF: 1.840 | ||
| Call Number | UA @ lucian @ c:irua:112982 | Serial | 1303 | ||
| Permanent link to this record | |||||
| Author | Horemans, B.; Van Holsbeke, C.; Vos, W.; Darchuk, L.; Novakovic, V.; Fontan, A.C.; de Backer, J.; van Grieken, R.; de Backer, W.; De Wael, K. | ||||
| Title | Particle deposition in airways of chronic respiratory patients exposed to an urban aerosol | Type | A1 Journal article | ||
| Year | 2012 | Publication | Environmental science and technology | Abbreviated Journal | Environ Sci Technol |
| Volume | 46 | Issue | 21 | Pages | 12162-12169 |
| Keywords | A1 Journal article; AXES (Antwerp X-ray Analysis, Electrochemistry and Speciation); Laboratory Experimental Medicine and Pediatrics (LEMP) | ||||
| Abstract | Urban atmospheres in modern cities carry characteristic mixtures of particulate pollution which are potentially aggravating for chronic respiratory patients (CRP). Although air quality surveys can be detailed, the obtained information is not always useful to evaluate human health effects. This paper presents a novel approach to estimate particle deposition rates in airways of CRP, based on real air pollution data. By combining computational fluid dynamics with physical-chemical characteristics of particulate pollution, deposition rates are estimated for particles of different toxicological relevance, that is, minerals, iron oxides, sea salts, ammonium salts, and carbonaceous particles. Also, it enables some qualitative evaluation of the spatial, temporal, and patient specific effects on the particle dose upon exposure to the urban atmosphere. Results show how heavy traffic conditions increases the deposition of anthropogenic particles in the trachea and lungs of respiratory patients (here, +0.28 and +1.5 μg·h1, respectively). In addition, local and synoptic meteorological conditions were found to have a strong effect on the overall dose. However, the pathology and age of the patient was found to be more crucial, with highest deposition rates for toxic particles in adults with a mild anomaly, followed by mild asthmatic children and adults with severe respiratory dysfunctions (7, 5, and 3 μg·h1, respectively). | ||||
| Address | |||||
| Corporate Author | Thesis | ||||
| Publisher | Place of Publication |
Easton, Pa | Editor | ||
| Language | Wos | 000310665000082 | Publication Date | 2012-10-04 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 0013-936X;1520-5851; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 6.198 | Times cited | 5 | Open Access | |
| Notes | ; We are grateful for the financial support of n.v. Vooruitzicht. Furthermore, co-workers at the environmental analysis research group are acknowledged for their help in the fieldwork. ; | Approved | Most recent IF: 6.198; 2012 IF: 5.257 | ||
| Call Number | UA @ lucian @ c:irua:101411 | Serial | 2557 | ||
| Permanent link to this record | |||||
| Author | de Backer, J.W.; Vos, W.G.; Vinchurkar, S.C.; Claes, R.; Drollmann, A.; Wulfrank, D.; Parizel, P.M.; Germonpré, P.; de Backer, W. | ||||
| Title | Validation of computational fluid dynamics in CT-based airway models with SPECT/CT1 | Type | A1 Journal article | ||
| Year | 2010 | Publication | Radiology | Abbreviated Journal | Radiology |
| Volume | 257 | Issue | 3 | Pages | 854-862 |
| Keywords | A1 Journal article; Condensed Matter Theory (CMT); Vision lab; Antwerp Surgical Training, Anatomy and Research Centre (ASTARC); Laboratory Experimental Medicine and Pediatrics (LEMP) | ||||
| Abstract | Purpose: To compare the results obtained by using numerical flow simulations with the results of combined single photon emission computed tomography (SPECT) and computed tomography (CT) and to demonstrate the importance of correct boundary conditions for the numerical methods to account for the large amount of interpatient variability in airway geometry. Materials and Methods: This study was approved by all relevant institutional review boards. All patients gave their signed informed consent. In this study, six patients with mild asthma (three men; three women; overall mean age, 46 years ± 17 [standard deviation]) underwent CT at functional residual capacity and total lung capacity, as well as SPECT/CT. CT data were used for segmentation and computational fluid dynamics (CFD) simulations. A comparison was made between airflow distribution, as derived with (a) SPECT/CT through tracer concentration analysis, (b) CT through lobar expansion measurement, and (c) CFD through flow computer simulation. Also, the heterogeneity of the ventilation was examined. Results: Good agreement was found between SPECT/CT, CT, and CFD in terms of airflow distribution and hot spot detection. The average difference for the internal airflow distribution was less than 3% for CFD and CT versus SPECT/CT. Heterogeneity in ventilation patterns could be detected with SPECT/CT and CFD. Conclusion: This results of this study show that patient-specific computer simulations with appropriate boundary conditions yield information that is similar to that obtained with functional imaging tools, such as SPECT/CT. | ||||
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| Corporate Author | Thesis | ||||
| Publisher | Place of Publication |
Easton, Pa | Editor | ||
| Language | Wos | 000284469300031 | Publication Date | 2010-11-17 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 0033-8419;1527-1315; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 7.296 | Times cited | 100 | Open Access | |
| Notes | ; Supported by Novartis. ; | Approved | Most recent IF: 7.296; 2010 IF: 6.069 | ||
| Call Number | UA @ lucian @ c:irua:85379 | Serial | 3831 | ||
| Permanent link to this record | |||||
| Author | Parizel, P.M.; Corthouts, B.; Snoeckx, A.; de Backer, J.; de Backer, W. | ||||
| Title | Klinische semiologie en radiologie | Type | H3 Book chapter | ||
| Year | 2007 | Publication | Abbreviated Journal | ||
| Volume | Issue | Pages | 133-146 | ||
| Keywords | H3 Book chapter; Condensed Matter Theory (CMT); Antwerp Surgical Training, Anatomy and Research Centre (ASTARC); Laboratory Experimental Medicine and Pediatrics (LEMP) | ||||
| Abstract | |||||
| Address | |||||
| Corporate Author | Thesis | ||||
| Publisher | Acco | Place of Publication |
Leuven | Editor | |
| Language | Wos | Publication Date | 0000-00-00 | ||
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | ISBN | Additional Links | UA library record | ||
| Impact Factor | Times cited | Open Access | |||
| Notes | Approved | Most recent IF: NA | |||
| Call Number | UA @ lucian @ c:irua:63801 | Serial | 1765 | ||
| Permanent link to this record | |||||
| Author | de Backer, J.W.; Vos, W.G.; Gorlé, C.D.; Germonpré, P.; Partoens, B.; Wuyts, F.L.; Parizel, P.M.; de Backer, W. | ||||
| Title | Flow analyses in the lower airways: patient-specific model and boundary conditions | Type | A1 Journal article | ||
| Year | 2008 | Publication | Medical engineering and physics | Abbreviated Journal | Med Eng Phys |
| Volume | 30 | Issue | 7 | Pages | 872-879 |
| Keywords | A1 Journal article; Condensed Matter Theory (CMT); Antwerp Surgical Training, Anatomy and Research Centre (ASTARC); Laboratory Experimental Medicine and Pediatrics (LEMP) | ||||
| Abstract | Computational fluid dynamics (CFD) is increasingly applied in the respiratory domain. The ability to simulate the flow through a bifurcating tubular system has increased the insight into the internal flow dynamics and the particular characteristics of respiratory flows such as secondary motions and inertial effects. The next step in the evolution is to apply the technique to patient-specific cases, in order to provide more information about pathological airways. This study presents a patient-specific approach where both the geometry and the boundary conditions (BC) are based on individual imaging methods using computed tomography (CT). The internal flow distribution of a 73-year-old female suffering from chronic obstructive pulmonary disease (COPD) is assessed. The validation is performed through the comparison of lung ventilation with gamma scintigraphy. The results show that in order to obtain agreement within the accuracy limits of the gamma scintigraphy scan, both the patient-specific geometry and the BC (driving pressure) play a crucial role. A minimal invasive test (CT scan) supplied enough information to perform an accurate CFD analysis. In the end it was possible to capture the pathological features of the respiratory system using the imaging and computational fluid dynamics techniques. This brings the introduction of this new technique in the clinical practice one step closer. | ||||
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| Corporate Author | Thesis | ||||
| Publisher | Place of Publication |
London | Editor | ||
| Language | Wos | 000259768300009 | Publication Date | 2007-12-26 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 1350-4533; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 1.819 | Times cited | 82 | Open Access | |
| Notes | Approved | Most recent IF: 1.819; 2008 IF: 2.216 | |||
| Call Number | UA @ lucian @ c:irua:71693 | Serial | 1224 | ||
| Permanent link to this record | |||||
| Author | Klingstedt, M.; Sundberg, M.; Eriksson, L.; Haigh, S.; Kirkland, A.; Grüner, D.; de Backer, A.; Van Aert, S.; Tarasaki, O. | ||||
| Title | Exit wave reconstruction from focal series of HRTEM images, single crystal XRD and total energy studies on SbxWO3+y (x\sim0.11) | Type | A1 Journal article | ||
| Year | 2012 | Publication | Zeitschrift für Kristallographie | Abbreviated Journal | Z Krist-Cryst Mater |
| Volume | 227 | Issue | 6 | Pages | 341-349 |
| Keywords | A1 Journal article; Electron microscopy for materials research (EMAT) | ||||
| Abstract | A new tungsten bronze in the SbWO system has been prepared in a solid state reaction from Sb2O3, WO3 and W metal powder. The average structure was determined by single crystal X-ray diffraction. SbxWO3+y (x ∼ 0.11) crystallizes in the orthorhombic space group Pm21n (no. 31), a = 27.8135(9) Å, b = 7.3659(2) Å and c = 3.8672(1) Å. The structure belongs to the (n)-ITB class of intergrowth tungsten bronzes. It contains slabs of hexagonal channels formed by six WO6 octahedra. These slabs are separated by three layers of WO6 octahedra that are arranged in a WO3-type fashion. The WO6 octahedra share all vertices to build up a three-dimensional framework. The hexagonal channels are filled with Sb atoms to ∼80% and additional O atoms. The atoms are shifted out of the center of the channels. Exit-wave reconstruction of focal series of high resolution-transmission-electron-microscope (HRTEM) images combined with statistical paramäeter estimation techniques allowed to study local ordering in the channels. Sb atoms in neighbouring channels tend to be displaced in the same direction, which is in agreement with total energy calculations on ordered structure models, but the ratio of the occupation of the two possible Sb sites varies from channel to channel. The structure of SbxWO3+y exhibits pronounced local modulations. | ||||
| Address | |||||
| Corporate Author | Thesis | ||||
| Publisher | Place of Publication |
München | Editor | ||
| Language | Wos | 000307314200003 | Publication Date | 2012-06-06 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 2194-4946; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 3.179 | Times cited | 4 | Open Access | |
| Notes | Fwo; Esteem 026019 | Approved | Most recent IF: 3.179; 2012 IF: NA | ||
| Call Number | UA @ lucian @ c:irua:101218 | Serial | 1131 | ||
| Permanent link to this record | |||||
| Author | Verhulst, S.L.; de Backer, J.; Van Gaal, L.; de Backer, W.; Desager, K. | ||||
| Title | Adenotonsillectomy as first-line treatment for sleep-disordered breathing in obese children | Type | L1 Letter to the editor | ||
| Year | 2008 | Publication | American journal of respiratory and critical care medicine | Abbreviated Journal | Am J Resp Crit Care |
| Volume | 177 | Issue | 12 | Pages | 1399 |
| Keywords | L1 Letter to the editor; Condensed Matter Theory (CMT); Laboratory Experimental Medicine and Pediatrics (LEMP) | ||||
| Abstract | |||||
| Address | |||||
| Corporate Author | Thesis | ||||
| Publisher | Place of Publication |
New York | Editor | ||
| Language | Wos | Publication Date | 0000-00-00 | ||
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 1073-449x; 1535-4970 | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 13.204 | Times cited | Open Access | ||
| Notes | Approved | Most recent IF: 13.204; 2008 IF: 9.792 | |||
| Call Number | UA @ lucian @ c:irua:68864 | Serial | 59 | ||
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| Author | de Backer, J.W.; Vos, W.G.; Verhulst, S.L.; de Backer, W. | ||||
| Title | Novel imaging techniques using computer methods for the evaluation of the upper airway in patients with sleep-disordered breathing: a comprehensive review | Type | A1 Journal article | ||
| Year | 2008 | Publication | Sleep medicine reviews | Abbreviated Journal | Sleep Med Rev |
| Volume | 12 | Issue | 6 | Pages | 437-447 |
| Keywords | A1 Journal article; Condensed Matter Theory (CMT); Laboratory Experimental Medicine and Pediatrics (LEMP) | ||||
| Abstract | Patients with sleep related breathing disorders (SRBD) can be treated with nasal continuous positive airway pressure (nCPAP) or with several upper airway (UA) interventions. While nCPAP is almost always effective when clinically well tolerated, the therapeutic outcome of UA surgery and UA devices is difficult to predict. The improvement of our capability to perform the latter predictions more accurately is of great clinical importance since it will prevent patients to be treated with ineffective, sometimes irreversible, techniques. In this review we describe the importance of new imaging methods in this respect. We first refer to the most important pathophysiological mechanisms known so far to play a role in SRBD, indicating that functional imaging could elucidate these mechanisms in a patient specific manner. Then we describe the new technologies that make UA imaging more functional referring to the data as they are presently available. Finally we summarise the studies that do indicate that the use of functional imaging of the UA in SRBD patients may significantly help to predict the clinical outcome after UA interventions. | ||||
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| Publisher | Place of Publication |
New York | Editor | ||
| Language | Wos | 000261904500003 | Publication Date | 2008-10-16 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 1087-0792; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 8.958 | Times cited | 33 | Open Access | |
| Notes | Approved | Most recent IF: 8.958; 2008 IF: 6.143 | |||
| Call Number | UA @ lucian @ c:irua:71640 | Serial | 2378 | ||
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| Author | van Holsbeke, C.; de Backer, J.; Vos, W.; Verdonck, P.; van Ransbeeck, P.; Claessens, T.; Braem, M.; Vanderveken, O.; de Backer, W. | ||||
| Title | Anatomical and functional changes in the upper airways of sleep apnea patients due to mandibular repositioning: a large scale study | Type | A1 Journal article | ||
| Year | 2011 | Publication | Journal of biomechanics | Abbreviated Journal | J Biomech |
| Volume | 44 | Issue | 3 | Pages | 442-449 |
| Keywords | A1 Journal article; Condensed Matter Theory (CMT); Vision lab; Laboratory Experimental Medicine and Pediatrics (LEMP); Translational Neurosciences (TNW) | ||||
| Abstract | The obstructive sleep apnea-hypopnea syndrome (OSAHS) is a sleep related breathing disorder. A popular treatment is the use of a mandibular repositioning appliance (MRA) which advances the mandibula during the sleep and decreases the collapsibility of the upper airway. The success rate of such a device is, however, limited and very variable within a population of patients. Previous studies using computational fluid dynamics have shown that there is a decrease in upper airway resistance in patients who improve clinically due to an MRA. In this article, correlations between patient-specific anatomical and functional parameters are studied to examine how MRA induced biomechanical changes will have an impact on the upper airway resistance. Low-dose computed tomography (CT) scans are made from 143 patients suffering from OSAHS. A baseline scan and a scan after mandibular repositioning (MR) are performed in order to study variations in parameters. It is found that MR using a simulation bite is able to induce resistance changes by changing the pharyngeal lumen. The change in minimal cross-sectional area is the best parameter to predict the change in upper airway resistance. Looking at baseline values, the ideal patients for MR induced resistance decrease seem to be women with short airways, high initial resistance and no baseline occlusion. | ||||
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New York, N.Y. | Editor | ||
| Language | Wos | 000287551000014 | Publication Date | 2010-10-23 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 0021-9290; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 2.664 | Times cited | 23 | Open Access | |
| Notes | ; ; | Approved | Most recent IF: 2.664; 2011 IF: 2.434 | ||
| Call Number | UA @ lucian @ c:irua:85305 | Serial | 112 | ||
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| Author | Vinchurkar, S.; De Backer, L.; Vos, W.; Van Holsbeke, C.; de Backer, J.; de Backer, W. | ||||
| Title | A case series on lung deposition analysis of inhaled medication using functional imaging based computational fluid dynamics in asthmatic patients : effect of upper airway morphology and comparison with in vivo data | Type | A1 Journal article | ||
| Year | 2012 | Publication | Inhalation Toxicology | Abbreviated Journal | Inhal Toxicol |
| Volume | 24 | Issue | 2 | Pages | 81-88 |
| Keywords | A1 Journal article; Pharmacology. Therapy; Biophysics and Biomedical Physics; Condensed Matter Theory (CMT); Laboratory Experimental Medicine and Pediatrics (LEMP) | ||||
| Abstract | Context: Asthma affects 20 million Americans resulting in an economic burden of approximately $18 billion in the US alone (Allergies and Asthma Foundation 2000; National Center for Environmental Health (NCEH) 1999). Research studies based on differences in patient-specific airway morphology for asthma and the associated effect on deposition of inhaled aerosols are currently not available in the literature. Therefore, the role of morphological variations such as upper airway (extrathoracic) occlusion is not well documented. Objective: Functional imaging based computational fluid dynamics (CFD) of the respiratory airways for five asthmatic subjects is performed in this study using computed tomography (CT) based patient-specific airway models and boundary conditions. Methods: CT scans for 5 asthma patients were used to reconstruct 3D lung models using segmentation software. An averaged inhalation profile and patient-specific lobar flow distribution were used to perform the simulation. The simulations were used to obtain deposition for BDP/Formoterol (R) HFA pMDI in the patient-specific airway models. Results: The lung deposition obtained using CFD was in excellent agreement with available in vivo data using the same product. Specifically, CFD resulted in 30% lung deposition, whereas in vivo lung deposition was reported to be approximately 31%. Conclusion: It was concluded that a combination of patient-specific airway models and lobar boundary conditions can be used to obtain accurate lung deposition estimates. Lower lung deposition can be expected for patients with higher extrathoracic resistance. Novel respiratory drug delivery devices need to accommodate population subgroups based on these morphological and anatomical differences in addition to subject age. | ||||
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| Publisher | Place of Publication |
New York, N.Y. | Editor | ||
| Language | Wos | 000299744800001 | Publication Date | 2012-01-20 | |
| Series Editor | Series Title | Abbreviated Series Title | |||
| Series Volume | Series Issue | Edition | |||
| ISSN | 0895-8378;1091-7691; | ISBN | Additional Links | UA library record; WoS full record; WoS citing articles | |
| Impact Factor | 1.751 | Times cited | 36 | Open Access | |
| Notes | ; ; | Approved | Most recent IF: 1.751; 2012 IF: 1.894 | ||
| Call Number | UA @ lucian @ c:irua:96238 | Serial | 286 | ||
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