A radiofrequency coil to facilitate B  1+ shimming and parallel imaging acceleration in three dimensions at 7 T

2010 ◽  
Vol 24 (7) ◽  
pp. 815-823 ◽  
Author(s):  
Kyle M. Gilbert ◽  
Andrew T. Curtis ◽  
Joseph S. Gati ◽  
L. Martyn Klassen ◽  
Ravi S. Menon
Keyword(s):  
Parallel Imaging ◽  
Three Dimensions ◽  
Radiofrequency Coil ◽  
Parallel Imaging Acceleration

High-resolution renal MRA: Comparison of image quality and vessel depiction with different parallel imaging acceleration factors

2006 ◽  
Vol 24 (1) ◽  
pp. 95-100 ◽  
Author(s):  
Henrik J. Michaely ◽  
Karin A. Herrmann ◽  
Harald Kramer ◽  
Olaf Dietrich ◽  
Gerhard Laub ◽  
...  
Keyword(s):  
High Resolution ◽  
Image Quality ◽  
Parallel Imaging ◽  
Renal Mra ◽  
Parallel Imaging Acceleration

scholarly journals Echo Planar Diffusion-Weighted Imaging: Possibilities and Considerations with 12- and 32-Channel Head Coils

2012 ◽  
Vol 2 ◽  
pp. 31 ◽  
Author(s):  
John N Morelli ◽  
Megan R Saettele ◽  
Rajesh A Rangaswamy ◽  
Lan Vu ◽  
Clint M Gerdes ◽  
...  
Keyword(s):  
Image Quality ◽  
Parallel Imaging ◽  
Brain Magnetic Resonance Imaging ◽  
Single Shot ◽  
Quality Improvements ◽  
Planar Imaging ◽  
Diffusion Weighted ◽  
Resolution Imaging ◽  
Echo Planar ◽  
Parallel Imaging Acceleration

Interest in clinical brain magnetic resonance imaging using 32-channel head coils for signal reception continues to increase. The present investigation assesses possibilities for improving diffusion-weighted image quality using a 32-channel in comparison to a conventional 12-channel coil. The utility of single-shot (ss) and an approach to readout-segmented (rs) echo planar imaging (EPI) are examined using both head coils. Substantial image quality improvements are found with rs-EPI. Imaging with a 32-channel head coil allows for implementation of greater parallel imaging acceleration factors or acquisition of scans at a higher resolution. Specifically, higher resolution imaging with rs-EPI can be achieved by increasing the number of readout segments without increasing echo-spacing or echo time to the degree necessary with ss-EPI — a factor resulting in increased susceptibility artifact and reduced signal-to-noise with the latter.

Parallel imaging acceleration of EPIK for reduced image distortions in fMRI

NeuroImage ◽  
2013 ◽  
Vol 73 ◽  
pp. 135-143 ◽  
Author(s):  
Seong Dae Yun ◽  
Martina Reske ◽  
Kaveh Vahedipour ◽  
Tracy Warbrick ◽  
N. Jon Shah
Keyword(s):  
Parallel Imaging ◽  
Parallel Imaging Acceleration

Five-Minute Five-Sequence Knee MRI Using Combined Simultaneous Multislice and Parallel Imaging Acceleration: Comparison with 10-Minute Parallel Imaging Knee MRI

Radiology ◽  
2021 ◽  
pp. 203655
Author(s):  
Filippo Del Grande ◽  
Ali Rashidi ◽  
Rodrigo Luna ◽  
Marco Delcogliano ◽  
Steven E. Stern ◽  
...  
Keyword(s):  
Parallel Imaging ◽  
Knee Mri ◽  
Simultaneous Multislice ◽  
Parallel Imaging Acceleration

High-resolution scanning electron microscopy (HRSEM) of mitochondria from various rat tissues

1988 ◽  
Vol 46 ◽  
pp. 14-15
Author(s):  
P.J. Lea ◽  
M.J. Hollenberg
Keyword(s):  
Electron Microscopy ◽  
Pigment Epithelium ◽  
Retinal Pigment ◽  
Rat Hepatocytes ◽  
Three Dimensions ◽  
Objective Lens ◽  
Rat Tissues ◽  
Thin Sections ◽  
Reconstruction Methods ◽  
Scanning Electron

Our current understanding of mitochondrial ultrastructure has been derived primarily from thin sections using transmission electron microscopy (TEM). This information has been extrapolated into three dimensions by artist's impressions (1) or serial sectioning techniques in combination with computer processing (2). The resolution of serial reconstruction methods is limited by section thickness whereas artist's impressions have obvious disadvantages.In contrast, the new techniques of HRSEM used in this study (3) offer the opportunity to view simultaneously both the internal and external structure of mitochondria directly in three dimensions and in detail.The tridimensional ultrastructure of mitochondria from rat hepatocytes, retinal (retinal pigment epithelium), renal (proximal convoluted tubule) and adrenal cortex cells were studied by HRSEM. The specimens were prepared by aldehyde-osmium fixation in combination with freeze cleavage followed by partial extraction of cytosol with a weak solution of osmium tetroxide (4). The specimens were examined with a Hitachi S-570 scanning electron microscope, resolution better than 30 nm, where the secondary electron detector is located in the column directly above the specimen inserted within the objective lens.

Inelastic Electron Scattering from Valence Electrons in Aluminum

1976 ◽  
Vol 34 ◽  
pp. 462-463
Author(s):  
P. E. Batson ◽  
C. H. Chen ◽  
J. Silcox
Keyword(s):  
Electron Scattering ◽  
Single Scattering ◽  
Three Dimensions ◽  
Inelastic Electron ◽  
Weak Beam ◽  
Scattering Spectrum ◽  
Valence Electrons ◽  
Diffraction Patterns ◽  
Electronic Scattering

We wish to report in this paper measurements of the inelastic scattering component due to the collective excitations (plasmons) and single particlehole excitations of the valence electrons in Al. Such scattering contributes to the diffuse electronic scattering seen in electron diffraction patterns and has recently been considered of significance in weak-beam images (see Gai and Howie) . A major problem in the determination of such scattering is the proper correction for multiple scattering. We outline here a procedure which we believe suitably deals with such problems and report the observed single scattering spectrum.In principle, one can use the procedure of Misell and Jones—suitably generalized to three dimensions (qx, qy and #x2206;E)--to derive single scattering profiles. However, such a computation becomes prohibitively large if applied in a brute force fashion since the quasi-elastic scattering (and associated multiple electronic scattering) extends to much larger angles than the multiple electronic scattering on its own.

Advantages of Complementary Stereo Images as Viewed with the Low-Temperature Field-Emission SEM

1992 ◽  
Vol 50 (2) ◽  
pp. 1314-1315
Author(s):  
William P. Wergin ◽  
Eric F. Erbe
Keyword(s):  
Fold Increase ◽  
Horizontal Displacement ◽  
Three Dimensions ◽  
Stereo Image ◽  
Stereo Pair ◽  
Sem Micrograph ◽  
Left And Right ◽  
The Common ◽  
The Brain ◽  
Pair Analysis

The eye-brain complex allows those of us with normal vision to perceive and evaluate our surroundings in three-dimensions (3-D). The principle factor that makes this possible is parallax - the horizontal displacement of objects that results from the independent views that the left and right eyes detect and simultaneously transmit to the brain for superimposition. The common SEM micrograph is a 2-D representation of a 3-D specimen. Depriving the brain of the 3-D view can lead to erroneous conclusions about the relative sizes, positions and convergence of structures within a specimen. In addition, Walter has suggested that the stereo image contains information equivalent to a two-fold increase in magnification over that found in a 2-D image. Because of these factors, stereo pair analysis should be routinely employed when studying specimens.Imaging complementary faces of a fractured specimen is a second method by which the topography of a specimen can be more accurately evaluated.

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