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	Author	de Backer, A.; Fatermans, J.; den Dekker, A.J.; Van Aert, S.
	Title	Atom counting			Type	H2 Book chapter
	Year	2021	Publication	Advances in imaging and electron physics T2 – Advances in imaging and electron physics	Abbreviated Journal
	Volume		Issue		Pages	91-144
	Keywords	H2 Book chapter; Electron microscopy for materials research (EMAT); Vision lab
	Abstract	In this chapter, a statistical model-based method to count the number of atoms of monotype crystalline nanostructures from high-resolution annular dark-field (ADF) scanning transmission electron microscopy (STEM) images is discussed in detail together with a thorough study on the possibilities and inherent limitations. We show that this method can be applied to nanocrystals of arbitrary shape, size, and atom type. The validity of the atom-counting results is confirmed by means of detailed image simulations and it is shown that the high sensitivity of our method enables us to count atoms with single atom sensitivity.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos		Publication Date	2021-03-06
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume	217	Series Issue		Edition
	ISSN		ISBN	978-0-12-824607-8; 1076-5670	Additional Links	UA library record
	Impact Factor		Times cited		Open Access	Not_Open_Access
	Notes	ERC Consolidator project funded by the European Union grant #770887 Picometrics			Approved	Most recent IF: NA
	Call Number	UA @ admin @ c:irua:177529			Serial	6776
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	Author	de Backer, A.; Fatermans, J.; den Dekker, A.J.; Van Aert, S.
	Title	Efficient fitting algorithm			Type	H2 Book chapter
	Year	2021	Publication	Advances in imaging and electron physics T2 – Advances in imaging and electron physics	Abbreviated Journal
	Volume		Issue		Pages	73-90
	Keywords	H2 Book chapter; Electron microscopy for materials research (EMAT)
	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 neighboring columns, enabling the analysis of a large field of view. To provide end-users with this well-established quantification method, a user friendly program, StatSTEM, is developed which is freely available under a GNU public license. In this chapter, this efficient algorithm is applied to three different nanostructures for which the analysis of a large field of view is required.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos		Publication Date	2021-03-06
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume	217	Series Issue		Edition
	ISSN		ISBN	978-0-12-824607-8; 1076-5670	Additional Links	UA library record
	Impact Factor		Times cited		Open Access	Not_Open_Access
	Notes	ERC Consolidator project funded by the European Union grant #770887 Picometrics			Approved	Most recent IF: NA
	Call Number	UA @ admin @ c:irua:177528			Serial	6778
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	Author	de Backer, A.; Fatermans, J.; den Dekker, A.J.; Van Aert, S.
	Title	General conclusions and future perspectives			Type	H2 Book chapter
	Year	2021	Publication	Advances in imaging and electron physics T2 – Advances in imaging and electron physics	Abbreviated Journal
	Volume		Issue		Pages	243-253
	Keywords	H2 Book chapter; Electron microscopy for materials research (EMAT); Vision lab
	Abstract	This chapter provides an overview of statistical and quantitative methodologies that have pushed (scanning) transmission electron microscopy ((S)TEM) toward accurate and precise measurements of unknown structure parameters for understanding the relation between the structure of a material and its properties. Hereby, statistical parameter estimation theory has extensively been used which enabled not only measuring atomic column positions, but also quantifying the number of atoms, and detecting atomic columns as accurately and precisely as possible from experimental images. As a general conclusion, it can be stated that advanced statistical techniques are ideal tools to perform quantitative electron microscopy at the atomic scale. In the future, statistical methods will continue to be developed and novel quantification procedures will open up new possibilities for studying material structures at the atomic scale.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos		Publication Date	2021-03-06
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume	217	Series Issue		Edition
	ISSN		ISBN	978-0-12-824607-8; 1076-5670	Additional Links	UA library record
	Impact Factor		Times cited		Open Access	Not_Open_Access
	Notes	ERC Consolidator project funded by the European Union grant #770887 Picometrics			Approved	Most recent IF: NA
	Call Number	UA @ admin @ c:irua:177533			Serial	6781
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	Author	Fatermans, J.; de Backer, A.; den Dekker, A.J.; Van Aert, S.
	Title	Image-quality evaluation and model selection with maximum a posteriori probability			Type	H2 Book chapter
	Year	2021	Publication	Advances in imaging and electron physics T2 – Advances in imaging and electron physics	Abbreviated Journal
	Volume		Issue		Pages	215-242
	Keywords	H2 Book chapter; Electron microscopy for materials research (EMAT); Vision lab
	Abstract	The maximum a posteriori (MAP) probability rule for atom column detection can also be used as a tool to evaluate the relation between scanning transmission electron microscopy (STEM) image quality and atom detectability. In this chapter, a new image-quality measure is proposed that correlates well with atom detectability, namely the integrated contrast-to-noise ratio (ICNR). Furthermore, the working principle of the MAP probability rule is described in detail showing a close relation to the principles of model-selection methods.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos		Publication Date	2021-03-06
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume	217	Series Issue		Edition
	ISSN		ISBN	978-0-12-824607-8; 1076-5670	Additional Links	UA library record
	Impact Factor		Times cited		Open Access	Not_Open_Access
	Notes	ERC Consolidator project funded by the European Union grant #770887 Picometrics			Approved	Most recent IF: NA
	Call Number	UA @ admin @ c:irua:177532			Serial	6782
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	Author	de Backer, A.; Fatermans, J.; den Dekker, A.J.; Van Aert, S.
	Title	Introduction			Type	H2 Book chapter
	Year	2021	Publication	Advances in imaging and electron physics T2 – Advances in imaging and electron physics	Abbreviated Journal
	Volume		Issue		Pages	1-28
	Keywords	H2 Book chapter; Electron microscopy for materials research (EMAT)
	Abstract
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos		Publication Date	2021-03-06
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume	217	Series Issue		Edition
	ISSN		ISBN	978-0-12-824607-8; 1076-5670	Additional Links	UA library record
	Impact Factor		Times cited		Open Access	Not_Open_Access
	Notes	ERC Consolidator project funded by the European Union grant #770887 Picometrics			Approved	Most recent IF: NA
	Call Number	UA @ admin @ c:irua:177525			Serial	6784
Permanent link to this record



	Author	de Backer, A.; Fatermans, J.; den Dekker, A.J.; Van Aert, S.
	Title	Optimal experiment design for nanoparticle atom counting from ADF STEM images			Type	H2 Book chapter
	Year	2021	Publication	Advances in imaging and electron physics T2 – Advances in imaging and electron physics	Abbreviated Journal
	Volume		Issue		Pages	145-175
	Keywords	H2 Book chapter; Electron microscopy for materials research (EMAT); Vision lab
	Abstract	In this chapter, the principles of detection theory are used to quantify the probability of error for atom counting from high-resolution scanning transmission electron microscopy (HRSTEM) 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 of the probability of error. We show that for very thin objects the low-angle annular dark-field (LAADF) regime is optimal and that for thicker objects the optimal inner detector angle increases.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos		Publication Date	2021-03-06
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume	217	Series Issue		Edition
	ISSN		ISBN	978-0-12-824607-8; 1076-5670	Additional Links	UA library record
	Impact Factor		Times cited		Open Access	Not_Open_Access
	Notes	ERC Consolidator project funded by the European Union grant #770887 Picometrics			Approved	Most recent IF: NA
	Call Number	UA @ admin @ c:irua:177530			Serial	6785
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	Author	de Backer, A.; Fatermans, J.; den Dekker, A.J.; Van Aert, S.
	Title	Statistical parameter estimation theory : principles and simulation studies			Type	H2 Book chapter
	Year	2021	Publication	Advances in imaging and electron physics T2 – Advances in imaging and electron physics	Abbreviated Journal
	Volume		Issue		Pages	29-72
	Keywords	H2 Book chapter; Electron microscopy for materials research (EMAT); Vision lab
	Abstract	In this chapter, the principles of statistical parameter estimation theory for a quantitative analysis of atomic-resolution electron microscopy images are introduced. Within this framework, electron microscopy images are described by a parametric statistical model. Here, parametric models are introduced for different types of electron microscopy images: reconstructed exit waves, annular dark-field (ADF) scanning transmission electron microscopy (STEM) images, and simultaneously acquired ADF and annular bright-field (ABF) STEM images. Furthermore, the Cramér-Rao lower bound (CRLB) is introduced, i.e. a theoretical lower bound on the variance of any unbiased estimator. This CRLB is used to quantify the precision of the structure parameters of interest, such as the atomic column positions and the integrated atomic column intensities.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos		Publication Date	2021-03-06
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume	217	Series Issue		Edition
	ISSN		ISBN	978-0-12-824607-8; 1076-5670	Additional Links	UA library record
	Impact Factor		Times cited		Open Access	Not_Open_Access
	Notes	ERC Consolidator project funded by the European Union grant #770887 Picometrics			Approved	Most recent IF: NA
	Call Number	UA @ admin @ c:irua:177527			Serial	6788
Permanent link to this record



	Author	De Backer, J.
	Title	The versatile nature of cytoglobin, the Swiss army knife among globins, with a preference for oxidative stress			Type	Doctoral thesis
	Year	2023	Publication		Abbreviated Journal
	Volume		Issue		Pages	XVIII, 232 p.
	Keywords	Doctoral thesis; Pharmacology. Therapy; Plasma Lab for Applications in Sustainability and Medicine – Antwerp (PLASMANT); Proteinscience, proteomics and epigenetic signaling (PPES)
	Abstract	Since its discovery 20 years ago, many studies have been performed to gain insight into the functional role of cytoglobin (Cygb). However, Cygb has been proven to be a promiscuous protein. Yet, there is a consensus that Cygb is a cytoprotective protein involved in redox homeostasis. CYGB is a ubiquitously expressed hexacoordinated globin that is highly expressed in melanocytes and is often found to be downregulated during melanocyte-to-melanoma transition. In Chapter III, we investigated the molecular mechanism through which CYGB could be involved in redox regulation. Here, we showed that CYGB contains two redox-sensitive cysteine residues and that the formation of an intramolecular disulfide bridge resulted in the heme group becoming more accessible to external ligands. This supports the hypothesis that Cys38 and Cys83 serve as sensitive redox sensors. In Chapter IV we showed that CYGB mRNA and protein levels were elevated upon exposure to hypoxia. Interestingly, this upregulation was most likely HIF-2α-dependent. We propose that in melanoma, HIF-2α, rather than HIF-1α, positively regulates CYGB under hypoxic conditions in a cell type specific way. In Chapter V, the cytotoxic effect of indirect NTP treatment in two melanoma cell lines with divergent endogenous CYGB expression levels was investigated. We confirmed that NTP endows cytotoxicity that induces cell death through apoptosis and that this was mediated through the production of ROS. Moreover, we showed that CYGB protects melanoma cells from ROS-induced apoptosis by the scavenging of ROS. Interestingly, CYGB expression influenced the expression of NRF2 and HO-1. We identified the lncRNA MEG3 as a possible mechanism through which NRF2 expression and its downstream target HO-1 can be regulated by CYGB. In chapter VI, increased basal ROS levels and higher degree of lipid peroxidation upon RSL3 treatment contributed to the increased sensitivity of CYGB knockdown G361 cells to ferroptosis. Furthermore, transcriptome analysis demonstrates the enrichment of multiple cancer malignancy pathways upon CYGB knockdown, supporting a tumor-suppressive role for CYGB. Remarkably, CYGB expression regulation was identified as a critical determinant of the ferroptosis–pyroptosis therapy response. This suggests that CYGB is involved in the regulation of multiple modes of programmed cell death. FInally, we sought to delineate the RONS that are responsible for plasma-induced ICD. Our results highlight the importance of the short-lived species. Furthermore, we are first to demonstrate that NTP-created vaccine is safely prepared and offers complete protection. Moreover, we provide conclusive evidence that direct application of NTP induces ICD in melanoma.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos		Publication Date
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	ISSN		ISBN		Additional Links	UA library record
	Impact Factor		Times cited		Open Access
	Notes				Approved	Most recent IF: NA
	Call Number	UA @ admin @ c:irua:193568			Serial	7277
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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.
	Address
	Corporate Author				Thesis
	Publisher		Place of Publication		Editor
	Language		Wos		Publication Date	2024-02-19
	Series Editor		Series Title		Abbreviated Series Title
	Series Volume		Series Issue		Edition
	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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