Dark field imaging of rattle-type silica nanorattles coated gold nanoparticles &lt;italic&gt;in vitro&lt;/italic&gt; and&lt;italic&gt; in vivo&lt;/italic&gt;

AbstractGrating-based X-ray dark-field imaging is a novel imaging modality with enormous technical progress during the last years. It enables the detection of microstructure impairment as in the healthy lung a strong dark-field signal is present due to the high number of air-tissue interfaces. Using the experience from setups for animal imaging, first studies with a human cadaver could be performed recently. Subsequently, the first dark-field scanner for in-vivo chest imaging of humans was developed. In the current study, the optimal tube voltage for dark-field radiography of the thorax in this setup was examined using an anthropomorphic chest phantom. Tube voltages of 50–125 kVp were used while maintaining a constant dose-area-product. The resulting dark-field and attenuation radiographs were evaluated in a reader study as well as objectively in terms of contrast-to-noise ratio and signal strength. We found that the optimum tube voltage for dark-field imaging is 70 kVp as here the most favorable combination of image quality, signal strength, and sharpness is present. At this voltage, a high image quality was perceived in the reader study also for attenuation radiographs, which should be sufficient for routine imaging. The results of this study are fundamental for upcoming patient studies with living humans.

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The study of the intracellular transportation of gold nanoparticles through dark field imaging

Tenth International Conference on Information Optics and Photonics ◽

10.1117/12.2518844 ◽

2018 ◽

Author(s):

Chun Huang ◽

Qian Li ◽

Liwei Liu ◽

Rui Hu ◽

Junle Qu

Keyword(s):

Gold Nanoparticles ◽

Dark Field ◽

Dark Field Imaging ◽

Field Imaging

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Method combining BAC film and positive staining for the characterization of DNA intermediates by dark-field electron microscopy

Biology Methods and Protocols ◽

10.1093/biomethods/bpaa012 ◽

2020 ◽

Vol 5 (1) ◽

Cited By ~ 1

Author(s):

Yann Benureau ◽

Eliana Moreira Tavares ◽

Ali-Akbar Muhammad ◽

Sonia Baconnais ◽

Eric Le Cam ◽

...

Keyword(s):

Electron Microscopy ◽

Dark Field ◽

In Vitro Assays ◽

Positive Staining ◽

Synthetic Dna ◽

Dark Field Imaging ◽

Alkyl Ammonium

Abstract DNA intermediate structures are formed in all major pathways of DNA metabolism. Transmission electron microscopy (TEM) is a tool of choice to study their choreography and has led to major advances in the understanding of these mechanisms, particularly those of homologous recombination (HR) and replication. In this article, we describe specific TEM procedures dedicated to the structural characterization of DNA intermediates formed during these processes. These particular DNA species contain single-stranded DNA regions and/or branched structures, which require controlling both the DNA molecules spreading and their staining for subsequent visualization using dark-field imaging mode. Combining BAC (benzyl dimethyl alkyl ammonium chloride) film hyperphase with positive staining and dark-field TEM allows characterizing synthetic DNA substrates, joint molecules formed during not only in vitro assays mimicking HR, but also in vivo DNA intermediates.

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Visualisation of the microcirculation of the nasal mucosa in vivo in different nasal disorders, using sidestream dark-field imaging

http://isrctn.org/> ◽

10.1186/isrctn67264420 ◽

2012 ◽

Author(s):

W J Fokkens

Keyword(s):

Nasal Mucosa ◽

Dark Field ◽

Sidestream Dark Field ◽

Dark Field Imaging ◽

Sidestream Dark Field Imaging ◽

Field Imaging

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What atomic resolution annular dark field imaging can tell us about gold nanoparticles on TiO2 (110)

Ultramicroscopy ◽

10.1016/j.ultramic.2009.07.006 ◽

2009 ◽

Vol 109 (12) ◽

pp. 1435-1446 ◽

Cited By ~ 8

Author(s):

S.D. Findlay ◽

N. Shibata ◽

Y. Ikuhara

Keyword(s):

Gold Nanoparticles ◽

Dark Field ◽

Atomic Resolution ◽

Dark Field Imaging ◽

Annular Dark Field ◽

Field Imaging

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Giant Faceting of Vicinal Si(001) Induced by Au Adsorption

Surface Review and Letters ◽

10.1142/s0218625x9800150x ◽

1998 ◽

Vol 05 (06) ◽

pp. 1167-1178 ◽

Cited By ~ 24

Author(s):

F.-J. Meyer Zu Heringdorf ◽

D. Kähler ◽

M. Horn-Von Hoegen ◽

Th. Schmidt ◽

E. Bauer ◽

...

Keyword(s):

Dark Field ◽

Growth Behavior ◽

Nucleation Process ◽

Vicinal Surface ◽

Dark Field Imaging ◽

Parallel Arrangement ◽

Kinetics Of ◽

Field Imaging ◽

Critical Coverage

4° vicinal Si(001) shows perfectly ordered terraces with a width of 4 nm which are separated by double steps. Adsorption of Au at 800°C results in a dramatic change of the step morphology: the surface decomposes into areas which are perfectly flat with a (001) orientation and (119) facets, which compensate for the macroscopic miscut. Extremely straight superterraces with a length limited only by the size of the sample (here 4 mm) and a width ranging from 400 nm to 4 μm are formed by massive Si mass transport. The extreme aspect ratio of 1:10 000 of this submicron structure is attributed to a heterogeneous nucleation process. SPA-LEED reveals a new, Au-induced incommensurate 5×3.2 reconstruction above a critical coverage as the driving force for the formation of large elongated (001) terraces. LEEM shows the strongly anisotropic nucleation process in vivo. Dark field imaging and microspot LEED techniques have been used to determine the influence of the different 5×3.2 domain orientations on the growth behavior of the (001) superterraces. The majority of domain terraces grow with a speed of more than 10 μm per second. The width and area of the (001) terraces increase proportionally to the Au coverage. The steps of the vicinal surface are accumulated in irregular step bunches. With further increasing Au coverage the step bunches are transformed into well-defined facets with a (119) orientation, as determined by SPA-LEED. The kinetics of the faceting process have been studied with SPA-LEED, REM, STM, and light diffraction using a HeNe laser, because the typical size of the superterraces is of the order of the wavelength of visible light: the resulting structure is visible to the bare eye. The parallel arrangement of superterraces acts as an irregular optical phase grating: illumination with white light results in stripes of all possible diffraction colors.

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