30 research outputs found
New electron source concept for single-shot sub-100 fs electron diffraction in the 100 keV range
We present a method for producing sub-100 fs electron bunches that are
suitable for single-shot ultrafast electron diffraction experiments in the 100
keV energy range. A combination of analytical results and state-of-the-art
numerical simulations show that it is possible to create 100 keV, 0.1 pC, 20 fs
electron bunches with a spotsize smaller than 500 micron and a transverse
coherence length of 3 nm, using established technologies in a table-top set-up.
The system operates in the space-charge dominated regime to produce
energy-correlated bunches that are recompressed by established radio-frequency
techniques. With this approach we overcome the Coulomb expansion of the bunch,
providing an entirely new ultrafast electron diffraction source concept
Fully three-dimensional sound speed-corrected multi-wavelength photoacoustic breast tomography
Photoacoustic tomography is a contrast agent-free imaging technique capable
of visualizing blood vessels and tumor-associated vascularization in breast
tissue. While sophisticated breast imaging systems have been recently
developed, there is yet much to be gained in imaging depth, image quality and
tissue characterization capability before clinical translation is possible. In
response, we have developed a hybrid photoacoustic and ultrasound-transmission
tomographic system PAM3. The photoacoustic component has for the first time
three-dimensional multi-wavelength imaging capability, and implements
substantial technical advancements in critical hardware and software
sub-systems. The ultrasound component enables for the first time, a
three-dimensional sound speed map of the breast to be incorporated in
photoacoustic reconstruction to correct for inhomogeneities, enabling accurate
target recovery. The results demonstrate the deepest photoacoustic breast
imaging to date namely 48 mm, with a more uniform field of view than hitherto,
and an isotropic spatial resolution that rivals that of Magnetic Resonance
Imaging. The in vivo performance achieved, and the diagnostic value of
interrogating angiogenesis-driven optical contrast as well as tumor mass sound
speed contrast, gives confidence in the system's clinical potential.Comment: 33 pages Main Body, 9 pages Supplementary Materia
Fully three-dimensional sound speed-corrected multi-wavelength photoacoustic breast tomography
Photoacoustic tomography is a contrast agent-free imaging technique capable of visualizing blood vessels and tumor-associated vascularization in breast tissue. While sophisticated breast imaging systems have been recently developed, there is yet much to be gained in imaging depth, image quality and tissue characterization capability before clinical translation is possible. In response, we have developed a hybrid photoacoustic and ultrasound-transmission tomographic system PAM3. The photoacoustic component has for the first time three-dimensional multi-wavelength imaging capability, and implements substantial technical advancements in critical hardware and software sub-systems. The ultrasound component enables for the first time, a three-dimensional sound speed map of the breast to be incorporated in photoacoustic reconstruction to correct for inhomogeneities, enabling accurate target recovery. The results demonstrate the deepest photoacoustic breast imaging to date namely 48 mm, with a more uniform field of view than hitherto, and an isotropic spatial resolution that rivals that of Magnetic Resonance Imaging. The in vivo performance achieved, and the diagnostic value of interrogating angiogenesis-driven optical contrast as well as tumor mass sound speed contrast, gives confidence in the system\'s clinical potential
Het co-assistentschap huisartsgeneeskunde: leerdoelen en voorwaarden
Contains fulltext :
22161___.PDF (publisher's version ) (Open Access
Educational objectives and requirements of an undergraduate clerkship in general practice : The outcome of a consensus procedure
Contains fulltext :
25708.PDF (publisher's version ) (Open Access
Het co-assistentschap huisartsgeneeskunde: leerdoelen en voorwaarden
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