Kanwarpal Singh

In vivo imaging of airway cilia and mucus clearance with micro-optical coherence tomography

We have designed and fabricated a 4 mm diameter rigid endoscopic probe to obtain high resolution micro-optical coherence tomography (µOCT) images from the tracheal epithelium of living swine. Our common-path fiber-optic probe used gradient-index focusing optics, a selectively coated prism reflector to implement a circular-obscuration apodization for depth-of-focus enhancement, and a common-path reference arm and an ultra-broadbrand supercontinuum laser to achieve high axial resolution. Benchtop characterization demonstrated lateral and axial resolutions of 3.4 μm and 1.7 μm, respectively (in tissue). Mechanical standoff rails flanking the imaging window allowed the epithelial surface to be maintained in focus without disrupting mucus flow. During in vivo imaging, relative motion was mitigated by inflating an airway balloon to hold the standoff rails on the epithelium. Software implemented image stabilization was also implemented during post-processing. The resulting image sequences yielded co-registered quantitative outputs of airway surface liquid and periciliary liquid layer thicknesses, ciliary beat frequency, and mucociliary transport rate, metrics that directly indicate airway epithelial function that have dominated in vitro research in diseases such as cystic fibrosis, but have not been available in vivo.

Multiglass properties and magnetoelectric coupling in the uniaxial anisotropic spin-cluster-glass Fe 2 Ti O 5

The compound

μOCT imaging using depth of focus extension by self-imaging wavefront division in a common-path fiber optic probe

{\mathrm{Fe}}_{2}\mathrm{Ti}{\mathrm{O}}_{5}

Multiferroicity and magneto-electric effect in Gd2BaNiO5

(FTO) is a well-known uniaxial anisotropic spin-glass insulator with two successive glassy freezing temperatures, i.e., transverse

Development of low temperature and high magnetic field X-ray diffraction facility

({T}_{TF}=9\phantom{\rule{0.16em}{0ex}}\mathrm{K})

Astigmatism corrected common path probe for optical coherence tomography.

and longitudinal

In-line optical fiber metallic mirror reflector for monolithic common path optical coherence tomography probes: IN LINE FIBER MIRROR FOR COMMON PATH OCT PROBES

({T}_{LF}=55\phantom{\rule{0.16em}{0ex}}\mathrm{K})

Optical coherence tomography-guided laser marking with tethered capsule endomicroscopy (Conference Presentation)

. In this article, we present the results of measurements of complex dielectric behavior, electric polarization as a function of temperature

Micro optical coherence tomography probe for high resolution imaging of the inner ear (Conference Presentation)

(T)

Contrast enhancement of microscopic birefringent crystals using polarization sensitive micro-optical coherence tomography (Conference Presentation)

, in addition to characterization by magnetic susceptibility and heat capacity, primarily to explore magnetoelectric (ME) coupling and multiglass properties in uniaxial anisotropic spin-cluster-glass FTO. The existence of two magnetic transitions is reflected in the isothermal magnetodielectric (MD) behavior in the sense that the sign of MD is different in the