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“Photonics for the Biosciences and Health:
In Vivo and Microscopic Information “
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Date: |
Download-files: |
Time: |
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Thursday, 17. Dec. 2015 |
Audio-only-Recording as MP3-File
(smallest possible size):
- Audio.mp3 (ca. 26 Mb) ============================================ Video-Recording for any system with MP4-support:
- Video.mp4 (ca. 242 Mb) |
15:15 – 16:20 |
Speaker :
Kevin Webb (
Abstract :
While
photonics has entered the mainstream of research in the biosciences and health,
the related revolutions are still in their infancies. I describe our recent
accomplishments and directions along three lines: in vivo optical molecular
imaging, coherent optical imaging, and optical nanotweezers and forces. We have
shown that it is possible to image molecular information through fluorescence
resonance energy transfer (FRET) parameters and related fluorescence
information in vivo. This means that it is in principle possible to determine
spatial maps of protein folding in vivo. Using fluorescence information, it
also becomes possible to achieve neural network maps of the whole brain using
direct information for the first time, and to determine drug kinetic
information that has been unavailable in pharmacology. I describe our recent
efforts along these lines that are made possible by our ability to relate
heavily scattering optical measurements to a parameterized forward model in
cost function, leading to computed images. We recently showed that speckle
intensity correlations over object position lead to information about the field
incident on a heavily scattering random medium and also a means to image
objects moving within the scattering medium. This indicates that it is in
principle possible to image objects based upon motion deep in tissue. Interestingly,
the measurements are sensitive to far-subwavelength motion, and this is motion
in a structured (speckled) field. Expanding this notion, I describe an imaging
method to achieve far-subwavelength resolution information based on motion with
structured illumination that does not require fluorescent labeling. Our basic
and applied work on nanophotonics leads to a means to trap nanoparticles and
hence study biological molecules without the need for large beads, and to a way
to apply local forces over tens of nanometers. I describe our recent
theoretical and experimental work related to nanotweezers and optical forces,
offering some fundamental perspectives on the relevant physics. I also
highlight key aspects of nanostructured materials in relation to the
illuminating light.