Placement sensitivity to aberration in optical imaging

Theories are developed to quantify the shift of image intensity extremum (/spl Delta/x) due to aberration. The theory on real, one-dimensional mask spectrum has been extended to complex, two-dimensional mask spectrum under coherent and partially coherent imaging. Verification of the formulae was performed on alternating phase-shifting mask (PSM) and contact array. Balanced third-order coma was used to illustrate the validity of the theories. It is found that the image shift due to aberration of alternating PSM decreases when the partial coherence factor increases. In general, the theories can be applied to any mask spectra and aberration functions.published_or_final_versio

Speed-dependent resolution analysis of ultrafast laser-scanning fluorescence microscopy

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Power enhanced and fast swept source for phase conjugate optical coherence tomography

FTuY - Coherence Tomography: Paper FTuY1We have developed a wavelength-swept source based on fiber parametric amplification and Fourier domain mode locking with increased power and speed to take full advantage of 2x resolution enhancement and dispersion cancellation of phase-conjugate OCT.postprintFrontiers in Optics 2010 / Laser Science XXVI (FiO/LS 2010), Rochester, N.Y., 24 October 2010. In Optics InfoBase, 201

Speckle Reduction of Retinal Optical Coherence Tomography Based on Contourlet Shrinkage

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Enhanced depth resolution in optical scanning holography using a configurable pupil

The optical scanning holography (OSH) technique can capture all the three-dimensional volume information of an object in a hologram via a single raster scan. The digital hologram can then be processed to reconstruct individual sectional images of the object. In this paper, we present a scheme to reconstruct sectional images in OSH with enhanced depth resolution, where a spatial light modulator (SLM) is adopted as a configurable point pupil. By switching the SLM between two states, different Fresnel zone plates (FZPs) are generated based on the same optical system. With extra information provided by different FZPs, a depth resolution at 0.7 μm can be achieved.published_or_final_versio

Model order reduction for neutral systems by moment matching

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Chromatic-dispersion-free transmission using time-reversal optical parametric amplifier

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Sufu and Gli3 repressor mediate the temporal basal-to-apical progression of hair cell differentiation in mammalian cochleae

Poster presentation - Theme 3: Development & stem cellsThe Sonic Hedgehog pathway plays important roles in mammalian inner ear development. Mutations of Shh, Smo and Gli3 lead to severe defects in mouse inner ear morphogenesis. However, knockout of Gli2 does not affect inner ear morphology or cochlear hair cell differentiation, suggesting that the Gli repressor function may be required for Hedgehog signaling during inner ear development. Sufu is a negative regulator of Hedgehog signaling and it functions to repress Gli activator and enhance Gli repressor ...postprin

High-speed spectroscopic OCT around 1550 nm based on dual-band swept laser source

We report a 45 kHz spectroscopic OCT system based on a swept laser source utilizing two wavelength bands. The source is generated by single-band swept laser input and a fiber optical parametric amplifier. The time-multiplexing architecture reduces the complexity of the coupling and detecting configuration in comparison with the previous dual-band swept-source setup. This high-speed spectroscopic OCT combines the advantages of the speed of the swept laser and contrast enhancement, in comparison with the time or spectral-domain spectroscopic OCT system. In the experiment, spectroscopic OCT imaging around 1550 nm is achieved for the first time. The difference in images at 1500 nm and 1600 nm clearly shows different back scattering and penetration properties which can be used for tissue classification and water content measurement.published_or_final_versio

Analysis of craniofacial defects in Six1/Eya1-associated Branchio-Oto-Renal Syndrome

Poster Session I - Morphogenesis: 205/B10117th ISDB 2013 cum 72nd Annual Meeting of the Society for Developmental Biology, 7th Latin American Society of Developmental Biology Meeting and 11th Congreso de la Sociedad Mexicana de Biologia del Desarrollo.Branchio-Oto-Renal (BOR) syndrome patients exhibit craniofacial and renal anomalies as well as deafness. BOR syndrome is caused by mutations in Six1 or Eya1, both of which regulate cell proliferation and differentiation. The molecular mechanism underlying the craniofacial and branchial arch (BA) defects in BOR syndrome is unclear. We have found that Hoxb3 is up-regulated in the second branchial arch (BA2) of Six1-/- mutants. Moreover, Hoxb3 over-expression in transgenic mice leads to BA abnormalities which are similar to the BA defects in Six1-/- or Eya1-/- mutants, suggesting a regulatory relationship among Six1, Eya1 and Hoxb3 genes. The aim of this study is to investigate the molecular mechanism underlying abnormal BA development in BOR syndrome using Six1 and Eya1 mutant mice. Two potential Six1 binding sites were identified on the Hoxb3 gene. In vitro and in vivo Chromatin IP assays showed that Six1 could directly bind to one of the sites specifically. Furthermore, using a chick in ovo luciferase assay we showed that Six1 could suppress gene expression through one of the specific binding sites. On the other hand, in Six1-/- mutants, we found that the Notch ligand Jag1 was up-regulated in BA2. Similarly, in Hoxb3 transgenic mice, ectopic expression of Jag1 could be also detected in BA2. To investigate the activation of Notch signaling pathway, we found that Notch intracellular domain (NICD), a direct indicator of Notch pathway activation, was up-regulated in BAs of Six1-/-; Eya1-/- double mutants. Our results indicate that Hoxb3 and Notch signaling pathway are involved in mediating the craniofacial defects of Six1/Eya1-associated Branchio-Oto-Renal Syndrome.postprin