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Records |
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Author |
Vos, W.; de Backer, J.; Poli, G.; De Volder, A.; Ghys, L.; Van Holsbeke, C.; Vinchurkar, S.; De Backer, L.; de Backer, W. |
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Title |
Novel functional imaging of changes in small airways of patients treated with extrafine beclomethasone/formoterol |
Type |
A1 Journal article |
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Year |
2013 |
Publication |
Respiration |
Abbreviated Journal |
Respiration |
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Volume |
86 |
Issue |
5 |
Pages |
393-401 |
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Keywords |
A1 Journal article; Biophysics and Biomedical Physics; Condensed Matter Theory (CMT); Laboratory Experimental Medicine and Pediatrics (LEMP) |
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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 |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
Basel |
Editor |
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Language |
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Wos |
000329046200006 |
Publication Date |
2013-04-12 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN  |
1423-0356;0025-7931; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
2.772 |
Times cited |
30 |
Open Access |
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Notes |
; ; |
Approved |
Most recent IF: 2.772; 2013 IF: 2.924 |
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Call Number |
UA @ lucian @ c:irua:113762 |
Serial |
2376 |
| Permanent link to this record |
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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. |
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Title |
Functional respiratory imaging as a tool to assess upper airway patency in children with obstructive sleep apnea |
Type |
A1 Journal article |
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Year |
2013 |
Publication |
Sleep Medicine |
Abbreviated Journal |
Sleep Med |
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Volume |
14 |
Issue |
5 |
Pages |
433-439 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT); Laboratory Experimental Medicine and Pediatrics (LEMP) |
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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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Thesis |
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Publisher |
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Place of Publication |
Amsterdam |
Editor |
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Language |
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Wos |
000318612100009 |
Publication Date |
2013-03-07 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1389-9457; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
3.391 |
Times cited |
18 |
Open Access |
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Notes |
; ; |
Approved |
Most recent IF: 3.391; 2013 IF: 3.100 |
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Call Number |
UA @ lucian @ c:irua:109015 |
Serial |
1302 |
| Permanent link to this record |
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Author |
Lin, A.; Sahun, M.; Biscop, E.; Verswyvel, H.; De Waele, J.; De Backer, J.; Theys, C.; Cuypers, B.; Laukens, K.; Berghe, W.V.; Smits, E.; Bogaerts, A. |
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Title |
Acquired non-thermal plasma resistance mediates a shift towards aerobic glycolysis and ferroptotic cell death in melanoma |
Type |
A1 Journal article |
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Year |
2023 |
Publication |
Drug resistance updates |
Abbreviated Journal |
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Volume |
67 |
Issue |
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Pages |
100914 |
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Keywords |
A1 Journal article; Pharmacology. Therapy; ADReM Data Lab (ADReM); Center for Oncological Research (CORE); Proteinscience, proteomics and epigenetic signaling (PPES); Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT) |
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Abstract |
To gain insights into the underlying mechanisms of NTP therapy sensitivity and resistance, using the firstever
NTP-resistant cell line derived from sensitive melanoma cells (A375).
Methods: Melanoma cells were exposed to NTP and re-cultured for 12 consecutive weeks before evaluation
against the parental control cells. Whole transcriptome sequencing analysis was performed to identify differentially
expressed genes and enriched molecular pathways. Glucose uptake, extracellular lactate, media acidification,
and mitochondrial respiration was analyzed to determine metabolic changes. Cell death inhibitors were
used to assess the NTP-induced cell death mechanisms, and apoptosis and ferroptosis was further validated via
Annexin V, Caspase 3/7, and lipid peroxidation analysis.
Results: Cells continuously exposed to NTP became 10 times more resistant to NTP compared to the parental cell
line of the same passage, based on their half-maximal inhibitory concentration (IC50). Sequencing and metabolic
analysis indicated that NTP-resistant cells had a preference towards aerobic glycolysis, while cell death analysis
revealed that NTP-resistant cells exhibited less apoptosis but were more vulnerable to lipid peroxidation and
ferroptosis.
Conclusions: A preference towards aerobic glycolysis and ferroptotic cell death are key physiological changes in
NTP-resistance cells, which opens new avenues for further, in-depth research into other cancer types. |
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Corporate Author |
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Thesis |
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Place of Publication |
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Editor |
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Language |
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Wos |
000925156500001 |
Publication Date |
2022-12-29 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1368-7646 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
24.3 |
Times cited |
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Open Access |
OpenAccess |
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Notes |
The authors would like to thank Dr. Christophe Deben and Ms. Hannah Zaryouh (Center for Oncological Research, University of Antwerp) for the use and their help with the D300e Digital Dispenser and Spark® Cyto, as well as Ms. Rapha¨elle Corremans (Laboratory Pathophysiology, University of Antwerp) for the use of their lactate meter. The authors would also like to acknowledge the help from Ms. Tias Verhezen and Mr. Cyrus Akbari, who was involved at the start of the project but could not continue due to the COVID-19 pandemic. The authors also acknowledge the resources and services provided by the VSC (Flemish Supercomputer Center). This work was funded in part by the Research Foundation – Flanders (FWO) and the Flemish Government. The FWO fellowships and grants that funded this work also include: 12S9221N (Abraham Lin), G044420N (Abraham Lin, Annemie Bogaerts), and 1S67621N (Hanne Verswyvel). We would also like to thank several patrons, as part of this research was funded by donations from different donors, including Dedert Schilde vzw, Mr. Willy Floren, and the Vereycken family. We would also like to acknowledge the support from the European Cooperation in Science & Technology (COST) Action on Therapeutical applications of Cold Plasmas (CA20114; PlasTHER). |
Approved |
Most recent IF: 24.3; 2023 IF: 10.906 |
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Call Number |
PLASMANT @ plasmant @c:irua:193167 |
Serial |
7240 |
| Permanent link to this record |
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Author |
de Backer, J.W.; Vos, W.G.; Gorlé, C.D.; Germonpré, P.; Partoens, B.; Wuyts, F.L.; Parizel, P.M.; de Backer, W. |
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Title |
Flow analyses in the lower airways: patient-specific model and boundary conditions |
Type |
A1 Journal article |
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Year |
2008 |
Publication |
Medical engineering and physics |
Abbreviated Journal |
Med Eng Phys |
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Volume |
30 |
Issue |
7 |
Pages |
872-879 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT); Antwerp Surgical Training, Anatomy and Research Centre (ASTARC); Laboratory Experimental Medicine and Pediatrics (LEMP) |
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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 |
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Thesis |
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Publisher |
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Place of Publication |
London |
Editor |
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Language |
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Wos |
000259768300009 |
Publication Date |
2007-12-26 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1350-4533; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
1.819 |
Times cited |
82 |
Open Access |
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Notes |
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Approved |
Most recent IF: 1.819; 2008 IF: 2.216 |
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Call Number |
UA @ lucian @ c:irua:71693 |
Serial |
1224 |
| Permanent link to this record |
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Author |
de Backer, J.; Vos, W.; Van Holsbeke, C.; Vinchurkar, S.; Claes, R.; Parizel, P.M.; de Backer, W. |
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Title |
Effect of high-dose N-acetylcysteine on airway geometry, inflammation, and oxidative stress in COPD patients |
Type |
A1 Journal article |
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Year |
2013 |
Publication |
International Journal Of Chronic Obstructive Pulmonary Disease |
Abbreviated Journal |
Int J Chronic Obstr |
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Volume |
8 |
Issue |
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Pages |
569-579 |
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Keywords |
A1 Journal article; Biophysics and Biomedical Physics; Condensed Matter Theory (CMT); Antwerp Surgical Training, Anatomy and Research Centre (ASTARC); Laboratory Experimental Medicine and Pediatrics (LEMP) |
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Abstract |
Background: Previous studies have demonstrated the potential beneficial effect of N-acetylcysteine (NAC) in chronic obstructive pulmonary disease (COPD). However, the required dose and responder phenotype remain unclear. The current study investigated the effect of high-dose NAC on airway geometry, inflammation, and oxidative stress in COPD patients. Novel functional respiratory imaging methods combining multislice computed tomography images and computer-based flow simulations were used with high sensitivity for detecting changes induced by the therapy. Methods: Twelve patients with Global Initiative for Chronic Obstructive Lung Disease stage II COPD were randomized to receive NAC 1800 mg or placebo daily for 3 months and were then crossed over to the alternative treatment for a further 3 months. Results: Significant correlations were found between image-based resistance values and glutathione levels after treatment with NAC (P = 0.011) and glutathione peroxidase at baseline (P = 0.036). Image-based resistance values appeared to be a good predictor for glutathione peroxidase levels after NAC (P = 0.02), changes in glutathione peroxidase levels (P = 0.035), and reduction in lobar functional residual capacity levels (P = 0.00084). In the limited set of responders to NAC therapy, the changes in airway resistance were in the same order as changes induced by budesonide/formoterol. Conclusion: A combination of glutathione, glutathione peroxidase, and imaging parameters could potentially be used to phenotype COPD patients who would benefit from addition of NAC to their current therapy. The findings of this small pilot study need to be confirmed in a larger pivotal trial. |
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Corporate Author |
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Thesis |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000327537300001 |
Publication Date |
2013-11-21 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1178-2005; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
3.157 |
Times cited |
21 |
Open Access |
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Notes |
; JDB is a founder/shareholder of FluidDA NV, Kontich, Belgium. WV, SV, and CVH are employed by FluidDA NV, and WDB is the director of FluidDA NV. PMP and RC have no conflicts of interest to report. The study was supported by Zambon SpA, Bresso, Italy. ; |
Approved |
Most recent IF: 3.157; 2013 IF: NA |
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Call Number |
UA @ lucian @ c:irua:112799 |
Serial |
813 |
| Permanent link to this record |
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Author |
De Backer, L.; Vos, W.; Dieriks, B.; Daems, D.; Verhulst, S.; Vinchurkar, S.; Ides, K.; de Backer, J.; Germonpré, P.; de Backer, W. |
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Title |
The effects of long-term noninvasive ventilation in hypercapnic COPD patients : a randomized controlled pilot study |
Type |
A1 Journal article |
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Year |
2011 |
Publication |
International journal of chronic obstructive pulmonary disease |
Abbreviated Journal |
Int J Chronic Obstr |
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Volume |
6 |
Issue |
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Pages |
615-624 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT); Laboratory Experimental Medicine and Pediatrics (LEMP) |
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Abstract |
Introduction: Noninvasive ventilation (NIV) is a well-established treatment for acute-on-chronic respiratory failure in hypercapnic COPD patients. Less is known about the effects of a long-term treatment with NIV in hypercapnic COPD patients and about the factors that may predict response in terms of improved oxygenation and lowered CO2 retention.Methods: In this study, we randomized 15 patients to a routine pharmacological treatment (n = 5, age 66 [standard deviation ± 6] years, FEV1 30.5 [±5.1] %pred, PaO2 65 [±6] mmHg, PaCO2 52.4 [±6.0] mmHg) or to a routine treatment and NIV (using the Synchrony BiPAP device [Respironics, Inc, Murrsville, PA]) (n = 10, age 65 [±7] years, FEV1 29.5 [±9.0] %pred, PaO2 59 [±13] mmHg, PaCO2 55.4 [±7.7] mmHg) for 6 months. We looked at arterial blood gasses, lung function parameters and performed a low-dose computed tomography of the thorax, which was later used for segmentation (providing lobe and airway volumes, iVlobe and iVaw) and post-processing with computer methods (providing airway resistance, iRaw) giving overall a functional image of the separate airways and lobes.Results: In both groups there was a nonsignificant change in FEV1 (NIV group 29.5 [9.0] to 38.5 [14.6] %pred, control group 30.5 [5.1] to 36.8 [8.7] mmHg). PaCO2 dropped significantly only in the NIV group (NIV: 55.4 [7.7] → 44.5 [4.70], P = 0.0076; control: 52.4 [6.0] → 47.6 [8.2], NS). Patients actively treated with NIV developed a more inhomogeneous redistribution of mass flow than control patients. Subsequent analysis indicated that in NIV-treated patients that improve their blood gases, mass flow was also redistributed towards areas with higher vessel density and less emphysema, indicating that flow was redistributed towards areas with better perfusion. There was a highly significant correlation between the % increase in mass flow towards lobes with a blood vessel density of >9% and the increase in PaO2. Improved ventilation–perfusion match and recruitment of previously occluded small airways can explain the improvement in blood gases.Conclusion: We can conclude that in hypercapnic COPD patients treated with long-term NIV over 6 months, a mass flow redistribution occurs, providing a better ventilation–perfusion match and hence better blood gases and lung function. Control patients improve homogeneously in iVaw and iRaw, without improvement in gas exchange since there is no improved ventilation/perfusion ratio or increased alveolar ventilation. These differences in response can be detected through functional imaging, which gives a more detailed report on regional lung volumes and resistances than classical lung function tests do. Possibly only patients with localized small airway disease are good candidates for long-term NIV treatment. To confirm this and to see if better arterial blood gases also lead to better health related quality of life and longer survival, we have to study a larger population. |
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Publisher |
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Place of Publication |
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Editor |
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Language |
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Wos |
000208709800066 |
Publication Date |
2011-11-18 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1178-2005; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
3.157 |
Times cited |
28 |
Open Access |
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Notes |
; ; |
Approved |
Most recent IF: 3.157; 2011 IF: NA |
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Call Number |
UA @ lucian @ c:irua:93164 |
Serial |
866 |
| Permanent link to this record |
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Author |
De Backer, L.A.; Vos, W.G.; Salgado, R.; de Backer, J.W.; Devolder, A.; Verhulst, S.L.; Claes, R.; Germonpré, P.R.; de Backer, W.A. |
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Title |
Functional imaging using computer methods to compare the effect of salbutamol and ipratropium bromide in patient-specific airway models of COPD |
Type |
A1 Journal article |
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Year |
2011 |
Publication |
International journal of chronic obstructive pulmonary disease |
Abbreviated Journal |
Int J Chronic Obstr |
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Volume |
6 |
Issue |
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Pages |
637-646 |
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Keywords |
A1 Journal article; Condensed Matter Theory (CMT); Vision lab; Laboratory Experimental Medicine and Pediatrics (LEMP) |
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Abstract |
Background: Salbutamol and ipratropium bromide improve lung function in patients with chronic obstructive pulmonary disease (COPD). However, their bronchodilating effect has not yet been compared in the central and distal airways. Functional imaging using computational fluid dynamics offers the possibility of making such a comparison. The objective of this study was to assess the effects of salbutamol and ipratropium bromide on the geometry and computational fluid dynamics-based resistance of the central and distal airways.Methods: Five patients with Global Initiative for Chronic Obstructive Lung Disease Stage III COPD were randomized to a single dose of salbutamol or ipratropium bromide in a crossover manner with a 1-week interval between treatments. Patients underwent lung function testing and a multislice computed tomography scan of the thorax that was used for functional imaging. Two hours after dosing, the patients again underwent lung function tests and repeat computed tomography.Results: Lung function parameters, including forced expiratory volume in 1 second, vital capacity, overall airway resistance, and specific airway resistance, changed significantly after administration of each product. On functional imaging, the bronchodilating effect was greater in the distal airways, with a corresponding drop in airway resistance, compared with the central airways. Salbutamol and ipratropium bromide were equally effective at first glance when looking at lung function tests, but when viewed in more detail with functional imaging, hyporesponsiveness could be shown for salbutamol in one patient. Salbutamol was more effective in the other patients.Conclusion: This pilot study gives an innovative insight into the modes of action of salbutamol and ipratropium bromide in patients with COPD, using the new techniques of functional imaging and computational fluid dynamics. |
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Place of Publication |
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Wos |
000208709800068 |
Publication Date |
2011-11-28 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1178-2005; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
3.157 |
Times cited |
25 |
Open Access |
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Notes |
; ; |
Approved |
Most recent IF: 3.157; 2011 IF: NA |
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Call Number |
UA @ lucian @ c:irua:93165 |
Serial |
1300 |
| Permanent link to this record |
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Author |
Van Aert, S.; de Backer, A.; Martinez, G.T.; Goris, B.; Bals, S.; Van Tendeloo, G.; Rosenauer, A. |
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Title |
Procedure to count atoms with trustworthy single-atom sensitivity |
Type |
A1 Journal article |
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Year |
2013 |
Publication |
Physical review : B : condensed matter and materials physics |
Abbreviated Journal |
Phys Rev B |
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Volume |
87 |
Issue |
6 |
Pages |
064107-6 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
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Abstract |
We report a method to reliably count the number of atoms from high-angle annular dark field scanning transmission electron microscopy images. A model-based analysis of the experimental images is used to measure scattering cross sections at the atomic level. The high sensitivity of these measurements in combination with a thorough statistical analysis enables us to count atoms with single-atom sensitivity. The validity of the results is confirmed by means of detailed image simulations. We will show that the method can be applied to nanocrystals of arbitrary shape, size, and atom type without the need for a priori knowledge about the atomic structure. |
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Place of Publication |
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Wos |
000315144700006 |
Publication Date |
2013-02-20 |
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Series Editor |
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Series Title |
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Abbreviated Series Title |
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Series Volume |
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Series Issue |
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Edition |
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ISSN |
1098-0121;1550-235X; |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
3.836 |
Times cited |
106 |
Open Access |
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Notes |
FWO; 262348 ESMI; 312483 ESTEEM2;246791 COUNTATOMS; Hercules 3; esteem2_jra2 |
Approved |
Most recent IF: 3.836; 2013 IF: 3.664 |
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Call Number |
UA @ lucian @ c:irua:105674 |
Serial |
2718 |
| Permanent link to this record |
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Author |
de Backer, J.W.; Vos, W.G.; Verhulst, S.L.; de Backer, W. |
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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 |
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Year |
2008 |
Publication |
Sleep medicine reviews |
Abbreviated Journal |
Sleep Med Rev |
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Volume |
12 |
Issue |
6 |
Pages |
437-447 |
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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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Address |
|
| |
Corporate Author |
|
Thesis |
|
| |
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 |
| 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 |
| Permanent link to this record |
| |
|
| |
|
Author |
Martinez, G.T.; de Backer, A.; Rosenauer, A.; Verbeeck, J.; Van Aert, S. |
| |
Title |
The effect of probe inaccuracies on the quantitative model-based analysis of high angle annular dark field scanning transmission electron microscopy images |
Type |
A1 Journal article |
| |
Year |
2014 |
Publication |
Micron |
Abbreviated Journal |
Micron |
| |
Volume |
63 |
Issue |
|
Pages |
57-63 |
| |
Keywords |
A1 Journal article; Engineering Management (ENM); Electron microscopy for materials research (EMAT) |
| |
Abstract |
Quantitative structural and chemical information can be obtained from high angle annular dark field scanning transmission electron microscopy (HAADF STEM) images when using statistical parameter estimation theory. In this approach, we assume an empirical parameterized imaging model for which the total scattered intensities of the atomic columns are estimated. These intensities can be related to the material structure or composition. Since the experimental probe profile is assumed to be known in the description of the imaging model, we will explore how the uncertainties in the probe profile affect the estimation of the total scattered intensities. Using multislice image simulations, we analyze this effect for Cs corrected and non-Cs corrected microscopes as a function of inaccuracies in cylindrically symmetric aberrations, such as defocus and spherical aberration of third and fifth order, and non-cylindrically symmetric aberrations, such as 2-fold and 3-fold astigmatism and coma. |
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Address |
|
| |
Corporate Author |
|
Thesis |
|
| |
Publisher |
|
Place of Publication |
Oxford |
Editor |
|
| |
Language |
|
Wos |
000338402500011 |
Publication Date |
2014-01-02 |
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
| |
ISSN |
0968-4328; |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| |
Impact Factor |
1.98 |
Times cited |
25 |
Open Access |
|
| |
Notes |
FWO (G.0393.11; G.0064.10; G.0374.13; G.0044.13); European Research Council under the 7th Framework Program (FP7); ERC GrantNo. 246791-COUNTATOMS and ERC Starting Grant No. 278510-VORTEX. A.R. thanks the DFG under contract number RO2057/8-1.The research leading to these results has received funding fromthe European Union 7th Framework Programme [FP7/2007-2013]under grant agreement no. 312483 (ESTEEM2).; esteem2ta ECASJO; |
Approved |
Most recent IF: 1.98; 2014 IF: 1.988 |
| |
Call Number |
UA @ lucian @ c:irua:113857UA @ admin @ c:irua:113857 |
Serial |
831 |
| Permanent link to this record |
| |
|
| |
|
Author |
Vingerhoets, R.; Spiller, M.; De Backer, J.; Adriaens, A.; Vlaeminck, S.E.; Meers, E. |
| |
Title |
Detailed nitrogen and phosphorus flow analysis, nutrient use efficiency and circularity in the agri-food system of a livestock-intensive region |
Type |
A1 Journal article |
| |
Year |
2023 |
Publication |
Journal of cleaner production |
Abbreviated Journal |
|
| |
Volume |
410 |
Issue |
|
Pages |
137278-13 |
| |
Keywords |
A1 Journal article; Engineering sciences. Technology; Sustainable Energy, Air and Water Technology (DuEL) |
| |
Abstract |
The agri-food value chain is a major cause of nitrogen (N) and phosphorus (P) emissions and associated environmental and health impacts. The EU's farm-to-fork strategy (F2F) demands an agri-food value chain approach to reduce nutrient emissions by 50% and fertilizer use by 20%. Substance flow analysis (SFA) is a method that can be applied to study complex systems such as the agri-food chain. A review of 60 SFA studies shows that they often lack detail by not sufficiently distinguishing between nodes, products and types of emissions. The present study aims to assess the added value of detail in SFAs and to illustrate that valuable indicators can be derived from detailed assessments. This aim will be attained by presenting a highly-detailed SFA for the livestock-intensive region of Flanders, Belgium. The SFA distinguishes 40 nodes and 1827 flows that are classified into eight different categories (e.g. by-products, point source emissions) following life cycle methods. Eight novel indicators were calculated, including indicators that assess the N and P recovery potential. Flanders has a low overall nutrient use efficiency (11% N, 18% P). About 55% of the N and 56% of the P embedded in recoverable streams are reused providing 35% and 37% of the total N and P input. Optimized nutrient recycling could replace 45% of N and 48% of P of the external nutrient input, exceeding the target set by the F2F strategy. Detailed accounting for N and P flows and nodes leads to the identification of more recoverable streams and larger N and P flows. More detailed flow accounting is a prerequisite for the quantification of technological intervention options. Future research should focus on including concentration and quality as a parameter in SFAs. |
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Address |
|
| |
Corporate Author |
|
Thesis |
|
| |
Publisher |
|
Place of Publication |
|
Editor |
|
| |
Language |
|
Wos |
000991013600001 |
Publication Date |
2023-04-21 |
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
| |
ISSN |
0959-6526 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| |
Impact Factor |
11.1 |
Times cited |
|
Open Access |
OpenAccess |
| |
Notes |
|
Approved |
Most recent IF: 11.1; 2023 IF: 5.715 |
| |
Call Number |
UA @ admin @ c:irua:196227 |
Serial |
7770 |
| Permanent link to this record |
| |
|
| |
|
Author |
Varambhia, A.M.; Jones, L.; De Backer, A.; Fauske, V.T.; Van Aert, S.; Ozkaya, D.; Nellist, P.D. |
| |
Title |
Quantifying a Heterogeneous Ru Catalyst on Carbon Black Using ADF STEM |
Type |
A1 Journal article |
| |
Year |
2016 |
Publication |
Particle and particle systems characterization |
Abbreviated Journal |
Part Part Syst Char |
| |
Volume |
33 |
Issue |
33 |
Pages |
438-444 |
| |
Keywords |
A1 Journal article; Engineering sciences. Technology; Electron microscopy for materials research (EMAT) |
| |
Abstract |
Ru catalysts are part of a set of late transition metal nanocatalysts that have garnered much interest for catalytic applications such as ammonia synthesis and fuel cell production. Their performance varies greatly depending on their morphology and size, these catalysts are widely studied using electron microscopy. Using recent developments in Annular Dark Field (ADF) Scanning Transmission Electron Microscopy (STEM) quantification techniques, a rapid atom counting procedure was utilized to document the evolution of a heterogeneous Ru catalyst supported on carbon black. Areas of the catalyst were imaged for approximately 15 minutes using ADF STEM. When the Ru clusters were exposed to the electron beam, the clusters changed phase from amorphous to crystalline. To quantify the thickness of the crystalline clusters, two techniques were applied (simulation and statistical decomposition) and compared. These techniques show that stable face centredcubic crystal structures in the form of rafts, between 2 and 8 atoms thick, were formed after the initial wetting of the carbon support. |
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Address |
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| |
Corporate Author |
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Thesis |
|
| |
Publisher |
|
Place of Publication |
|
Editor |
|
| |
Language |
|
Wos |
000379970000012 |
Publication Date |
2016-06-17 |
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
| |
ISSN |
0934-0866 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| |
Impact Factor |
4.474 |
Times cited |
4 |
Open Access |
|
| |
Notes |
The authors would like to thank the EPSRC and Johnson Matthey for funding this work as part of a CASE-Award studentship. The research leading to these results has received funding from the European Union Seventh Framework Programme under Grant Agreement 312483 – ESTEEM2 (Integrated Infrastructure Initiative–I3). We would like to thank Brian Theobald and Jonathan Sharman from JMTC for provision of the samples The authors gratefully acknowledge the Research Foundation Flanders (FWO, Belgium) for funding and for a postdoctoral grant to ADB. The microscope used was funded by the INFRASTRUKTUR Grant 197405 (NORTEM) program of the Research Council of Norway.; esteem2_jra2 |
Approved |
Most recent IF: 4.474 |
| |
Call Number |
c:irua:134036 c:irua:134036 |
Serial |
4086 |
| 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 |
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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. |
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Address |
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| |
Corporate Author |
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Thesis |
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| |
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 |
| |
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| |
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Author |
Kirkwood, N.; De Backer, A.; Altantzis, T.; Winckelmans, N.; Longo, A.; Antolinez, F.V.; Rabouw, F.T.; De Trizio, L.; Geuchies, J.J.; Mulder, J.T.; Renaud, N.; Bals, S.; Manna, L.; Houtepen, A.J. |
| |
Title |
Locating and controlling the Zn content in In(Zn)P quantum dots |
Type |
A1 Journal article |
| |
Year |
2019 |
Publication |
Chemistry of materials |
Abbreviated Journal |
Chem Mater |
| |
Volume |
32 |
Issue |
32 |
Pages |
557-565 |
| |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
| |
Abstract |
Zinc is routinely employed in the synthesis of InP quantum dots (QDs) to improve the photoluminescence efficiency and carrier mobility of the resulting In(Zn)P alloy nanostructures. The exact location of Zn in the final structures and the mechanism by which it enhances the optoelectronic properties of the QDs is debated. We use synchrotron X-ray absorbance spectroscopy to show that the majority of Zn in In(Zn)P QDs is located at their surface as Zn-carboxylates. However, a small amount of Zn is present inside the bulk of the QDs with the consequent contraction of their lattice, as confirmed by combining high resolution high-angle annular dark-field imaging scanning transmission electron microscopy (HAADF-STEM) with statistical parameter estimation theory. We further demonstrate that the Zn content and its incorporation into the QDs can be tuned by the ligation of commonly employed Zn carboxylate precursors: the use of highly reactive Zn-acetate leads to the formation of undesired Zn3P2 and the final nanostructures being characterized by broad optical features, whereas Zn-carboxylates with longer carbon chains lead to InP crystals with much lower zinc content and narrow optical features. These results can explain the differences between structural and optical properties of In(Zn)P samples reported across the literature, and provide a rational method to tune the amount of Zn in InP nanocrystals and to drive the incorporation of Zn either as surface Zn-carboxylate, as a substitutional dopant inside the InP crystal lattice, or even predominantly as Zn3P2. |
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Address |
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| |
Corporate Author |
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Thesis |
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Publisher |
|
Place of Publication |
|
Editor |
|
| |
Language |
|
Wos |
000507721600056 |
Publication Date |
2019-12-13 |
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
| |
ISSN |
0897-4756 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| |
Impact Factor |
9.466 |
Times cited |
39 |
Open Access |
OpenAccess |
| |
Notes |
A.J.H. acknowledges support from the European Research Council Horizon 2020 ERC Grant Agreement No. 678004 (Doping on Demand). This research is supported by the Dutch Technology Foundation TTW, which is part of The Netherlands Organization for Scientific Research (NWO), and which is partly funded by Ministry of Economic Affairs. SB acknowledges funding from the European Research Council (grant 815128 REALNANO). The authors gratefully acknowledge funding from the Research Foundation Flanders (FWO, Belgium) through project funding G.0381.16N and a postdoctoral grant to A.D.B. AJH, LM and JM acknowledge support from the H2020 Collaborative Project TEQ (Grant No. 766900).; sygma |
Approved |
Most recent IF: 9.466 |
| |
Call Number |
EMAT @ emat @c:irua:165234 |
Serial |
5438 |
| Permanent link to this record |
| |
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| |
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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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Address |
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Corporate Author |
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Thesis |
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| |
Publisher |
|
Place of Publication |
New York, N.Y. |
Editor |
|
| |
Language |
|
Wos |
000299744800001 |
Publication Date |
2012-01-20 |
| |
Series Editor |
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Series Title |
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Abbreviated Series Title |
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| |
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 |
| Permanent link to this record |
| |
|
| |
|
Author |
Bals, S.; Goris, B.; de Backer, A.; Van Aert, S.; Van Tendeloo, G. |
| |
Title |
Atomic resolution electron tomography |
Type |
A1 Journal article |
| |
Year |
2016 |
Publication |
MRS bulletin |
Abbreviated Journal |
Mrs Bull |
| |
Volume |
41 |
Issue |
41 |
Pages |
525-530 |
| |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
| |
Abstract |
Over the last two decades, three-dimensional (3D) imaging by transmission electron microscopy or “electron tomography” has evolved into a powerful tool to investigate a variety of nanomaterials in different fields, such as life sciences, chemistry, solid-state physics, and materials science. Most of these results were obtained with nanometer-scale resolution, but different approaches have recently pushed the resolution to the atomic level. Such information is a prerequisite to understand the specific relationship between the atomic structure and the physicochemical properties of (nano) materials. We provide an overview of the latest progress in the field of atomic-resolution electron tomography. Different imaging and reconstruction approaches are presented, and state-of-the-art results are discussed. This article demonstrates the power and importance of electron tomography with atomic-scale resolution. |
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Address |
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Corporate Author |
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Thesis |
|
| |
Publisher |
|
Place of Publication |
Pittsburgh, Pa |
Editor |
|
| |
Language |
|
Wos |
000382508100012 |
Publication Date |
2016-07-07 |
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
| |
ISSN |
0883-7694 |
ISBN |
|
Additional Links |
UA library record; WoS full record; WoS citing articles |
| |
Impact Factor |
5.199 |
Times cited |
19 |
Open Access |
OpenAccess |
| |
Notes |
; The authors gratefully acknowledge funding from the Research Foundation Flanders (G.0381.16N, G.036915, G.0374.13, and funding of postdoctoral grants to B.G. and A.D.B.). S.B. acknowledges the European Research Council, ERC Grant Number 335078-Colouratom. The research leading to these results received funding from the European Union Seventh Framework Program under Grant Agreements 312483 (ESTEEM2). The authors would like to thank the colleagues who have contributed to this work, including K.J. Batenburg, J. De Beenhouwer, R. Erni, M.D. Rossell, W. Van den Broek, L. Liz-Marzan, E. Carbo-Argibay, S. Gomez-Grana, P. Lievens, M. Van Bael, B. Partoens, B. Schoeters, and J. Sijbers. ; ecas_sara |
Approved |
Most recent IF: 5.199 |
| |
Call Number |
UA @ lucian @ c:irua:135690 |
Serial |
4299 |
| Permanent link to this record |
| |
|
| |
|
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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Address |
|
| |
Corporate Author |
|
Thesis |
|
| |
Publisher |
|
Place of Publication |
Amsterdam |
Editor |
|
| |
Language |
|
Wos |
000236042300003 |
Publication Date |
2005-11-30 |
| |
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 |
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 |
| Permanent link to this record |
| |
|
| |
|
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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Address |
|
| |
Corporate Author |
|
Thesis |
|
| |
Publisher |
|
Place of Publication |
Amsterdam |
Editor |
|
| |
Language |
|
Wos |
000324474900005 |
Publication Date |
2013-05-17 |
| |
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 |
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 |
| Permanent link to this record |
| |
|
| |
|
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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Address |
|
| |
Corporate Author |
|
Thesis |
|
| |
Publisher |
|
Place of Publication |
Amsterdam |
Editor |
|
| |
Language |
|
Wos |
000351237800008 |
Publication Date |
2014-12-03 |
| |
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 |
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 |
| Permanent link to this record |
| |
|
| |
|
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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Address |
|
| |
Corporate Author |
|
Thesis |
|
| |
Publisher |
|
Place of Publication |
Amsterdam |
Editor |
|
| |
Language |
|
Wos |
000324474900006 |
Publication Date |
2013-06-01 |
| |
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 |
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 |
| Permanent link to this record |
| |
|
| |
|
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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Address |
|
| |
Corporate Author |
|
Thesis |
|
| |
Publisher |
|
Place of Publication |
Amsterdam |
Editor |
|
| |
Language |
|
Wos |
000300461200004 |
Publication Date |
2011-07-28 |
| |
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 |
8 |
Open Access |
|
| |
Notes |
Fwo |
Approved |
Most recent IF: 2.843; 2011 IF: 2.471 |
| |
Call Number |
UA @ lucian @ c:irua:91879 |
Serial |
1438 |
| Permanent link to this record |
| |
|
| |
|
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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Address |
|
| |
Corporate Author |
|
Thesis |
|
| |
Publisher |
|
Place of Publication |
Amsterdam |
Editor |
|
| |
Language |
|
Wos |
000351237800007 |
Publication Date |
2014-11-11 |
| |
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 |
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 |
| Permanent link to this record |
| |
|
| |
|
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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Address |
|
| |
Corporate Author |
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Thesis |
|
| |
Publisher |
|
Place of Publication |
Amsterdam |
Editor |
|
| |
Language |
|
Wos |
000331092200003 |
Publication Date |
2013-11-09 |
| |
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 |
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 |
| Permanent link to this record |
| |
|
| |
|
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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Address |
|
| |
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. |
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Address |
|
| |
Corporate Author |
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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 |
Gonnissen, J.; De Backer, A.; den Dekker, A.J.; Sijbers, J.; Van Aert, S. |
| |
Title |
Detecting and locating light atoms from high-resolution STEM images: The quest for a single optimal design |
Type |
A1 Journal article |
| |
Year |
2016 |
Publication |
Ultramicroscopy |
Abbreviated Journal |
Ultramicroscopy |
| |
Volume |
170 |
Issue |
170 |
Pages |
128-138 |
| |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Vision lab |
| |
Abstract |
In the present paper, the optimal detector design is investigated for both detecting and locating light atoms from high resolution scanning transmission electron microscopy (HR STEM) images. The principles of detection theory are used to quantify the probability of error for the detection of light atoms from HR STEM images. To determine the optimal experiment design for locating light atoms, use is made of the so-called Cramer-Rao Lower Bound (CRLB). It is investigated if a single optimal design can be found for both the detection and location problem of light atoms. Furthermore, the incoming electron dose is optimised for both research goals and it is shown that picometre range precision is feasible for the estimation of the atom positions when using an appropriate incoming electron dose under the optimal detector settings to detect light atoms. |
| |
Address |
Electron Microscopy for Materials Science (EMAT), University of Antwerp, Groenenborgerlaan 171, B-2020 Antwerp, Belgium. Electronic address: sandra.vanaert@uantwerpen.be |
| |
Corporate Author |
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Thesis |
|
| |
Publisher |
|
Place of Publication |
|
Editor |
|
| |
Language |
English |
Wos |
000386925500014 |
Publication Date |
2016-07-26 |
| |
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 |
6 |
Open Access |
|
| |
Notes |
The authors acknowledge financial support from the Research Foundation Flanders (FWO, Belgium) through project fundings (G.0368.15, G.0369.15 and G.0374.13) and a postdoctoral research grant to A. De Backer. The research leading to these results has also received funding from the European Union Seventh Framework Programme [FP7/2007-2013] under Grant agreement no. 312483 (ESTEEM2). The authors would also like to thank A. Rosenauer for providing access to the STEMsim software and Gerardo T. Martinez for fruitful discussions.; esteem2_jra2 |
Approved |
Most recent IF: 2.843 |
| |
Call Number |
c:irua:135337 c:irua:135337 |
Serial |
4128 |
| Permanent link to this record |
| |
|
| |
|
Author |
De Backer, A.; van den Bos, K.H.W.; Van den Broek, W.; Sijbers, J.; Van Aert, S. |
| |
Title |
StatSTEM: An efficient approach for accurate and precise model-based quantification of atomic resolution electron microscopy images |
Type |
A1 Journal article |
| |
Year |
2016 |
Publication |
Ultramicroscopy |
Abbreviated Journal |
Ultramicroscopy |
| |
Volume |
171 |
Issue |
171 |
Pages |
104-116 |
| |
Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Vision lab |
| |
Abstract |
An efficient model-based estimation algorithm is introduced to quantify the atomic column positions and intensities from atomic resolution (scanning) transmission electron microscopy ((S)TEM) images. This algorithm uses the least squares estimator on image segments containing individual columns fully accounting for overlap between neighbouring columns, enabling the analysis of a large field of view. For this algorithm, the accuracy and precision with which measurements for the atomic column positions and scattering cross-sections from annular dark field (ADF) STEM images can be estimated, has been investigated. The highest attainable precision is reached even for low dose images. Furthermore, the advantages of the model-based approach taking into account overlap between neighbouring columns are highlighted. This is done for the estimation of the distance between two neighbouring columns as a function of their distance and for the estimation of the scattering cross-section which is compared to the integrated intensity from a Voronoi cell. To provide end-users this well-established quantification method, a user friendly program, StatSTEM, is developed which is freely available under a GNU public license. |
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Address |
|
| |
Corporate Author |
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Thesis |
|
| |
Publisher |
|
Place of Publication |
|
Editor |
|
| |
Language |
|
Wos |
000389106200014 |
Publication Date |
2016-09-09 |
| |
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 |
43 |
Open Access |
|
| |
Notes |
The authors acknowledge financial support from the Research Foundation Flanders (FWO, Belgium) through project fundings (G.0393.11, G.0064.10 and G.0374.13), a Ph.D. research grant to K.H.W. van den Bos, and a postdoctoral research grant to A. De Backer. The research leading to these results has received funding from the European Union Seventh Framework Programme under Grant Agreement 312483 – ESTEEM2 (Integrated Infrastructure Initiative-I3). A. Rosenauer is acknowledged for providing the STEMsim program.; esteem2_jra2 |
Approved |
Most recent IF: 2.843 |
| |
Call Number |
EMAT @ emat @ c:irua:135516 |
Serial |
4280 |
| Permanent link to this record |
| |
|
| |
|
Author |
Gonnissen, J.; De Backer, A.; den Dekker, A.J.; Sijbers, J.; Van Aert, S. |
| |
Title |
Atom-counting in High Resolution Electron Microscopy: TEM or STEM – that's the question |
Type |
A1 Journal article |
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Year |
2016 |
Publication |
Ultramicroscopy |
Abbreviated Journal |
Ultramicroscopy |
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Volume |
174 |
Issue |
174 |
Pages |
112-120 |
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Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT); Vision lab |
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Abstract |
In this work, a recently developed quantitative approach based on the principles of detection theory is used in order to determine the possibilities and limitations of High Resolution Scanning Transmission Electron Microscopy (HR STEM) and HR TEM for atom-counting. So far, HR STEM has been shown to be an appropriate imaging mode to count the number of atoms in a projected atomic column. Recently, it has been demonstrated that HR TEM, when using negative spherical aberration imaging, is suitable for atom-counting as well. The capabilities of both imaging techniques are investigated and compared using the probability of error as a criterion. It is shown that for the same incoming electron dose, HR STEM outperforms HR TEM under common practice standards, i.e. when the decision is based on the probability function of the peak intensities in HR TEM and of the scattering cross-sections in HR STEM. If the atom-counting decision is based on the joint probability function of the image pixel values, the dependence of all image pixel intensities as a function of thickness should be known accurately. Under this assumption, the probability of error may decrease significantly for atom-counting in HR TEM and may, in theory, become lower as compared to HR STEM under the predicted optimal experimental settings. However, the commonly used standard for atom-counting in HR STEM leads to a high performance and has been shown to work in practice. |
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Wos |
000403342200013 |
Publication Date |
2016-10-27 |
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Series Editor |
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Edition |
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ISSN |
0304-3991 |
ISBN |
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Additional Links |
UA library record; WoS full record; WoS citing articles |
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Impact Factor |
2.843 |
Times cited |
2 |
Open Access |
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Notes |
The authors gratefully acknowledge financial support from the Research Foundation Flanders (FWO, Belgium) through project fundings (G.0368.15N, G.0369.15N, G.0374.13N, and WO.010.16N) and a postdoctoral grant to A. De Backer. The research leading to these results has received funding from the European Union Seventh Framework Programme [FP7/2007-2013] under Grant agreement no. 312483 (ESTEEM2). |
Approved |
Most recent IF: 2.843 |
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Call Number |
EMAT @ emat @ c:irua:137102 |
Serial |
4315 |
| Permanent link to this record |
