1,200 research outputs found
In vivo laser Doppler holography of the human retina
The eye offers a unique opportunity for non-invasive exploration of
cardiovascular diseases. Optical angiography in the retina requires sensitive
measurements, which hinders conventional full-field laser Doppler imaging
schemes. To overcome this limitation, we used digital holography to perform
laser Doppler perfusion imaging of the human retina in vivo with near-infrared
light. Wideband measurements of the beat frequency spectrum of optical
interferograms recorded with a 39 kHz CMOS camera are analyzed by short-time
Fourier transformation. Power Doppler images and movies drawn from the zeroth
moment of the power spectrum density reveal blood flows in retinal and
choroidal vessels over 512 512 pixels covering 2.4 2.4 mm
on the retina with a 13 ms temporal resolution.Comment: 5 pages, 5 figure
New Kids on the Blogs
The article deals with of the phenomenon of Comic BlogsEtude du phénomène des blogs en bande dessinéePeer reviewe
A Generalized Primitive Element Theorem
We deal with the following variant of the primitive element theorem: any commutative strongly separable extension of a commutative ring can be embedded in another one having primitive element. This statement holds for connected strongly separable extension of commutative rings which are either local or connected semilocal. We show that it holds for a more general family of rings, that is, for connected commutative rings whose quotient ring by the corresponding Jacobson radical is von Neumann regular and locally uniform. Some properties of the (connected) separable closure of such rings are also given as an application of this result.</p
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