scholarly journals A parallel imaging approach to wide-field MR microscopy

2011 ◽  
Vol 68 (3) ◽  
pp. 850-856 ◽  
Author(s):  
Mary Preston McDougall ◽  
Steven M. Wright
Keyword(s):  
Parallel Imaging ◽  
Wide Field ◽  
Mr Microscopy ◽  
Imaging Approach

scholarly journals Ghost artifact removal using a parallel imaging approach

2005 ◽  
Vol 54 (4) ◽  
pp. 1002-1009 ◽  
Author(s):  
Richard Winkelmann ◽  
Peter Börnert ◽  
Olaf Dössel
Keyword(s):  
Parallel Imaging ◽  
Artifact Removal ◽  
Imaging Approach

scholarly journals Spectrally Extended Line Field Optical Coherence Tomography Angiography

2021 ◽  
Author(s):  
Si Chen ◽  
Kan Lin ◽  
Linbo Liu
Keyword(s):  
Optical Coherence Tomography ◽  
Motion Tracking ◽  
Parallel Imaging ◽  
Optical Coherence Tomography Angiography ◽  
Low Cost ◽  
Wide Field ◽  
Optical Coherence ◽  
Line Field ◽  
Spectral Domain Oct ◽  
Flow Information

Abstract The widespread usage of optical coherence tomography angiography (OCTA) is hindered by technical gaps including limited field of view (FOV), lack of quantitative flow information, and suboptimal motion correction. We introduce spectrally extended line field (SELF) OCTA that provides advanced solutions to these challenges. SELF-OCTA breaks the speed limitation and achieves two-fold gain in FOV without sacrificing microvascular details and signal strength through parallel imaging. It also relieves the requirement for shorter exposure time in wide-field applications, so that sufficient sensitivity to slow flow is maintained, particularly in spectral-domain OCT. Towards quantitative angiography, the ‘frequency flow’ mechanism overcomes the speed bottleneck by obviating the requirement for superfluous B-scans. In addition, this mechanism facilitates OCTA-data based motion tracking. Since it can be implemented in existing OCT devices without significant hardware modification or affecting existing functions, SELF-OCTA will make non-invasive, wide-field, quantitative, and low-cost angiographic imaging available to larger patient populations.

STM studies of crystal growth

1991 ◽  
Vol 49 ◽  
pp. 374-375
Author(s):  
M. G. Lagally
Keyword(s):  
Crystal Growth ◽  
Molecular Beam ◽  
Chemical Vapor ◽  
Sputter Deposition ◽  
Field Of View ◽  
Scanning Tunneling ◽  
Wide Field ◽  
Tunneling Microscopy ◽  
Wide Field Of View ◽  
The One

It has been recognized since the earliest days of crystal growth that kinetic processes of all Kinds control the nature of the growth. As the technology of crystal growth has become ever more refined, with the advent of such atomistic processes as molecular beam epitaxy, chemical vapor deposition, sputter deposition, and plasma enhanced techniques for the creation of “crystals” as little as one or a few atomic layers thick, multilayer structures, and novel materials combinations, the need to understand the mechanisms controlling the growth process is becoming more critical. Unfortunately, available techniques have not lent themselves well to obtaining a truly microscopic picture of such processes. Because of its atomic resolution on the one hand, and the achievable wide field of view on the other (of the order of micrometers) scanning tunneling microscopy (STM) gives us this opportunity. In this talk, we briefly review the types of growth kinetics measurements that can be made using STM. The use of STM for studies of kinetics is one of the more recent applications of what is itself still a very young field.

Design of a Spectroscopic Low-Energy Emission Microscope

1990 ◽  
Vol 48 (1) ◽  
pp. 358-359
Author(s):  
Lee H. Veneklasen
Keyword(s):  
Parallel Imaging ◽  
Objective Lens ◽  
Energy Window ◽  
Flat Surfaces ◽  
Beam Voltage ◽  
New Instrument ◽  
Real Time Image ◽  
Image Planes ◽  
Backscatter Diffraction ◽  
Time Image

This paper discusses some of the unique aspects of a spectroscopic emission microscope now being tested in Clausthal. The instrument is designed for the direct parallel imaging of both elastic and inelastic electrons from flat surfaces. Elastic contrast modes of the familiar LEEM include large and small angle LEED, mirror microscopy, backscatter diffraction contrast (for imaging of surface structure), and phase contrast (for imaging of step dynamics)(1). Inelastic modes include topology sensitive secondary, and work function sensitive photoemission. Most important, the new instrument will also allow analytical imaging using characteristic Auger or soft X-ray emissions. The basic instrument has been described by Bauer and Telieps (2). This configuration has been redesigned to include an airlock, and a LaB6 gun, triple condensor lens, magnetic objective lens, a double focussing separator field, an imaging energy analyzer, and a real time image processor.Fig. 1 shows the new configuration. The basic beam voltage supply Vo = 20 KV, upon which separate supplies for the gun Vg, specimen Vs, lens electrode Vf, and analyzer bias Vb float. The incident energy at the sample can be varied from Vs = 0-1 KV for elastic imaging, or from Vg + Vs = (3 + Vs) KV for inelastic imaging. The image energy window Vs±V/2 may be varied without readjusting either the illumation, or imaging/analyzer optics. The diagram shows conjugate diffraction and image planes. The apertures defining incoming Humiliation and outgoing image angles are placed below the separator magnet to allow for their independent optimization. The instrument can illuminate and image 0.5-100 μm fields at 0-1 keV emission energies with an energy window down to 0.2 eV.

Coarctation of the abdominal aorta: Demonstration of a rare anomaly using contrast-enhanced MR-angiography

VASA ◽  
2009 ◽  
Vol 38 (1) ◽  
pp. 66-71 ◽  
Author(s):  
Schubert
Keyword(s):  
Abdominal Aorta ◽  
Mr Angiography ◽  
Parallel Imaging ◽  
Left Renal Vein ◽  
Systemic Hypertension ◽  
Contrast Enhanced ◽  
Younger Age ◽  
Maximum Intensity Projections ◽  
Collateral Vessels ◽  
First Time

We describe a case of aortic coarctation at the level of the infrarenal abdominal aorta which is encountered in less than six individuals in one million. In contrast to aortic narrowing above or including the renal arteries, this seems to be a relatively benign anomaly without systemic hypertension or impaired renal function. For the first time in this type of anomaly, contrast-enhanced MR angiography (ce-MRA) on a multi-receiver channel MR system, with an 8-channel phased array coil and parallel imaging was used. Ce-MRA displayed a tortuous, narrowed aortic segment that was found to be associated with mesenteric artery stenosis and compression of the orthotopic left renal vein, also known as the nutcracker phenomenon. All major aortic branches could be depicted using 3D surface-shaded displays and subvolume maximum intensity projections (MIPs). Collateral vessels of the abdominal wall were identified using whole-volume MIPs. Since the majority of aortic malformations are diagnosed at a younger age, and many suffer from renal insufficiency, we conclude that ce-MRA will eventually place conventional DSA as the modality of choice in malformations of the abdominal aorta.

Wide-field subsecond temporal resolution optical monitoring systems for detection and study of cosmic hazards

2013 ◽  
Vol 183 (8) ◽  
pp. 888-894
Author(s):  
G.M. Beskin ◽  
S.V. Karpov ◽  
V.L. Plokhotnichenko ◽  
S.F. Bondar ◽  
A.V. Perkov ◽  
...  
Keyword(s):  
Temporal Resolution ◽  
Monitoring Systems ◽  
Wide Field ◽  
Optical Monitoring
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