Now showing 1 - 4 of 4
  • 2016Conference Paper
    [["dc.contributor.author","Töpperwien, Mareike"],["dc.contributor.author","Krenkel, Martin"],["dc.contributor.author","Quade, Felix"],["dc.contributor.author","Salditt, Tim"],["dc.contributor.editor","Khounsary, Ali M."],["dc.contributor.editor","Dorssen, Gert E. van"],["dc.date.accessioned","2017-09-07T11:54:05Z"],["dc.date.available","2017-09-07T11:54:05Z"],["dc.date.issued","2016"],["dc.description.abstract","Due to the large penetration depth and small wavelength hard x-rays offer a unique potential for 3D biomedical and biological imaging, combining capabilities of high resolution and large sample volume. However, in classical absorption-based computed tomography, soft tissue only shows a weak contrast, limiting the actual resolution. With the advent of phase-contrast methods, the much stronger phase shift induced by the sample can now be exploited. For high resolution, free space propagation behind the sample is particularly well suited to make the phase shift visible. Contrast formation is based on the self-interference of the transmitted beam, resulting in object-induced intensity modulations in the detector plane. As this method requires a sufficiently high degree of spatial coherence, it was since long perceived as a synchrotron-based imaging technique. In this contribution we show that by combination of high brightness liquid-metal jet microfocus sources and suitable sample preparation techniques, as well as optimized geometry, detection and phase retrieval, excellent three-dimensional image quality can be obtained, revealing the anatomy of a cobweb spider in high detail. This opens up new opportunities for 3D virtual histology of small organisms. Importantly, the image quality is finally augmented to a level accessible to automatic 3D segmentation."],["dc.identifier.doi","10.1117/12.2246460"],["dc.identifier.gro","3145109"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/2809"],["dc.language.iso","en"],["dc.notes.intern","Crossref Import"],["dc.notes.status","public"],["dc.publisher","SPIE"],["dc.publisher.place","Bellingham, Washington"],["dc.relation.conference","Advances in Laboratory-Based X-Ray Sources, Optics, and Applications"],["dc.relation.eventend","2016-08-31"],["dc.relation.eventlocation","San Diego, Calif."],["dc.relation.eventstart","2016-08-30"],["dc.relation.ispartof","Advances in Laboratory-Based X-Ray Sources, Optics, and Applications V"],["dc.relation.orgunit","Institut für Röntgenphysik"],["dc.relation.workinggroup","RG Salditt (Structure of Biomolecular Assemblies and X-Ray Physics)"],["dc.subject.gro","x-ray imaging"],["dc.subject.gro","biomedical tomography"],["dc.title","Laboratory-based x-ray phase-contrast tomography enables 3D virtual histology"],["dc.type","conference_paper"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","no"],["dspace.entity.type","Publication"]]
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  • 2017Journal Article Research Paper
    [["dc.bibliographiccitation.firstpage","282"],["dc.bibliographiccitation.issue","4"],["dc.bibliographiccitation.journal","Acta Crystallographica Section A Foundations and Advances"],["dc.bibliographiccitation.lastpage","292"],["dc.bibliographiccitation.volume","73"],["dc.contributor.author","Krenkel, Martin"],["dc.contributor.author","Toepperwien, Mareike"],["dc.contributor.author","Alves, Frauke"],["dc.contributor.author","Salditt, Tim"],["dc.date.accessioned","2022-03-01T11:47:06Z"],["dc.date.available","2022-03-01T11:47:06Z"],["dc.date.issued","2017"],["dc.description.abstract","X-ray tomography at the level of single biological cells is possible in a low-dose regime, based on full-field holographic recordings, with phase contrast originating from free-space wave propagation. Building upon recent progress in cellular imaging based on the illumination by quasi-point sources provided by X-ray waveguides, here this approach is extended in several ways. First, the phase-retrieval algorithms are extended by an optimized deterministic inversion, based on a multi-distance recording. Second, different advanced forms of iterative phase retrieval are used, operational for single-distance and multi-distance recordings. Results are compared for several different preparations of macrophage cells, for different staining and labelling. As a result, it is shown that phase retrieval is no longer a bottleneck for holographic imaging of cells, and how advanced schemes can be implemented to cope also with high noise and inconsistencies in the data."],["dc.description.abstract","X-ray tomography at the level of single biological cells is possible in a low-dose regime, based on full-field holographic recordings, with phase contrast originating from free-space wave propagation. Building upon recent progress in cellular imaging based on the illumination by quasi-point sources provided by X-ray waveguides, here this approach is extended in several ways. First, the phase-retrieval algorithms are extended by an optimized deterministic inversion, based on a multi-distance recording. Second, different advanced forms of iterative phase retrieval are used, operational for single-distance and multi-distance recordings. Results are compared for several different preparations of macrophage cells, for different staining and labelling. As a result, it is shown that phase retrieval is no longer a bottleneck for holographic imaging of cells, and how advanced schemes can be implemented to cope also with high noise and inconsistencies in the data."],["dc.identifier.doi","10.1107/S2053273317007902"],["dc.identifier.doi","10.1107/s2053273317007902"],["dc.identifier.gro","3142469"],["dc.identifier.pii","S2053273317007902"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/103911"],["dc.language.iso","en"],["dc.notes.intern","DOI-Import GROB-531"],["dc.notes.status","final"],["dc.relation.eissn","2053-2733"],["dc.relation.issn","2053-2733"],["dc.relation.orgunit","Institut für Röntgenphysik"],["dc.relation.workinggroup","RG Salditt (Structure of Biomolecular Assemblies and X-Ray Physics)"],["dc.rights.uri","http://creativecommons.org/licenses/by/2.0/uk/legalcode"],["dc.subject.gro","x-ray imaging"],["dc.subject.gro","biomedical tomography"],["dc.title","Three-dimensional single-cell imaging with X-ray waveguides in the holographic regime"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","no"],["dc.type.subtype","original_ja"],["dspace.entity.type","Publication"]]
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  • 2016Conference Paper
    [["dc.contributor.author","Töpperwien, Mareike"],["dc.contributor.author","Krenkel, Martin"],["dc.contributor.author","Müller, Kristin"],["dc.contributor.author","Salditt, Tim"],["dc.contributor.editor","Stock, Stuart R."],["dc.contributor.editor","Müller, Bert"],["dc.contributor.editor","Wang, Ge"],["dc.date.accessioned","2017-09-07T11:54:06Z"],["dc.date.available","2017-09-07T11:54:06Z"],["dc.date.issued","2016"],["dc.description.abstract","Assessing the three-dimensional architecture of neuronal tissues with sub-cellular resolution presents a significant analytical challenge. Overcoming the limitations associated with serial slicing, phase-contrast x-ray tomography has the potential to contribute to this goal. Even compact laboratory CT at an optimized liquid-metal jet micro- focus source combined with suitable phase-retrieval algorithms and preparation protocols can yield renderings with single cell sensitivity in millimeter sized brain areas of mouse. Here, we show the capabilities of the setup by imaging a Golgi-Cox impregnated mouse brain. Towards higher resolution we extend these studies at our recently upgraded waveguide-based cone-beam holo-tomography instrument GINIX at DESY. This setup allows high resolution recordings with adjustable field of view and resolution, down to the voxel sizes in the range of a few ten nanometers. The recent results make us confident that important issues of neuronal connectivity can be addressed by these methods, and that 3D (virtual) histology with nanoscale resolution will become an attractive modality for neuroscience research."],["dc.identifier.doi","10.1117/12.2238496"],["dc.identifier.gro","3145108"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/2808"],["dc.language.iso","en"],["dc.notes.intern","Crossref Import"],["dc.notes.status","public"],["dc.publisher","SPIE-Intl Soc Optical Eng"],["dc.publisher.place","Bellingham, Washington"],["dc.relation.conference","Developments in X-Ray Tomography X"],["dc.relation.eventend","2016-08-31"],["dc.relation.eventlocation","San Diego, Calif."],["dc.relation.eventstart","2016-08-29"],["dc.relation.isbn","978-1-5106-0325-7"],["dc.relation.ispartof","Developments in X-Ray Tomography X"],["dc.relation.issn","0277-786X"],["dc.relation.orgunit","Institut für Röntgenphysik"],["dc.relation.workinggroup","RG Salditt (Structure of Biomolecular Assemblies and X-Ray Physics)"],["dc.subject.gro","x-ray imaging"],["dc.subject.gro","biomedical tomography"],["dc.title","Phase-contrast tomography of neuronal tissues: from laboratory- to high resolution synchrotron CT"],["dc.type","conference_paper"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","no"],["dspace.entity.type","Publication"]]
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  • 2014Conference Paper
    [["dc.bibliographiccitation.artnumber","9212-26"],["dc.contributor.author","Krenkel, Martin"],["dc.contributor.author","Töpperwien, Mareike"],["dc.contributor.author","Bartels, Matthias"],["dc.contributor.author","Lingor, Paul"],["dc.contributor.author","Schild, Detlev"],["dc.contributor.author","Salditt, Tim"],["dc.contributor.editor","Stock, Stuart R."],["dc.date.accessioned","2017-09-07T11:54:06Z"],["dc.date.available","2017-09-07T11:54:06Z"],["dc.date.issued","2014"],["dc.description.abstract","We use propagation based hard x-ray phase contrast tomography to explore the three dimensional structure of neuronal tissues from the organ down to sub-cellular level, based on combinations of synchrotron radiation and laboratory sources. To this end a laboratory based microfocus tomography setup has been built in which the geometry was optimized for phase contrast imaging and tomography. By utilizing phase retrieval algorithms, quantitative reconstructions can be obtained that enable automatic renderings without edge artifacts. A high brightness liquid metal microfocus x-ray source in combination with a high resolution detector yielding a resolution down to 1.5 μm. To extend the method to nanoscale resolution we use a divergent x-ray waveguide beam geometry at the synchrotron. Thus, the magnification can be easily tuned by placing the sample at different defocus distances. Due to the small Fresnel numbers in this geometry the measured images are of holographic nature which poses a challenge in phase retrieval."],["dc.identifier.doi","10.1117/12.2060390"],["dc.identifier.gro","3145112"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/2812"],["dc.language.iso","en"],["dc.notes.intern","Crossref Import"],["dc.notes.status","public"],["dc.publisher","SPIE"],["dc.publisher.place","Bellingham, Washington"],["dc.relation.conference","9th Conference Developments in X-Ray Tomography"],["dc.relation.eventend","2014-08-20"],["dc.relation.eventlocation","San Diego, Calif."],["dc.relation.eventstart","2014-08-18"],["dc.relation.ispartof","Developments in X-Ray Tomography IX"],["dc.relation.issn","0277-786X"],["dc.relation.orgunit","Institut für Röntgenphysik"],["dc.relation.workinggroup","RG Salditt (Structure of Biomolecular Assemblies and X-Ray Physics)"],["dc.subject.gro","x-ray imaging"],["dc.subject.gro","biomedical tomography"],["dc.title","X-ray phase contrast tomography from whole organ down to single cells"],["dc.type","conference_paper"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","no"],["dspace.entity.type","Publication"]]
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