We introduce a new fluorescence microscopy technique that maps the axial position of a fluorophore with subnanometer precision. The interference of the emission of fluorophores in proximity to a reflecting surface results in fringes in the fluorescence spectrum that provide a unique signature of the axial position of the fluorophore. The nanometer sensitivity is demonstrated by measuring the he...

PURPOSE To investigate the topography of the central and peripheral cornea in a group of young adult subjects with a range of normal refractive errors. METHODS Corneal topography data were acquired for 100 young adult subjects by a method that allows central and peripheral maps to be combined to produce one large, extended corneal topography map. This computer-based method involves matching t...

We demonstrate the use of tone-burst excitation and time-gated spectral analysis for photoacoustic Doppler mapping of flow in an unperturbed vessel phantom and in a vessel with a spatially varying lumen. The method, which mimics pulsed Doppler ultrasound, enables simultaneous measurement of axial position and flow as well as complete characterization of the Doppler spectrum over a wide range of...

Stability issues have been a major concern for the realization of broadband tunability of the gyrotron backward-wave oscillator gyro-BWO . Multimode, time-dependent simulations are employed to examine the stability properties of the gyro-BWO. It is shown that the gyro-BWO is susceptible to both nonstationary oscillations and axial mode competition in the course of frequency tuning. Regions of n...

A general method of deprojecting two-dimensional images to reconstruct the three dimensional structure of the projected object – specifically X-ray, Sunyaev-Zel'dovich (SZ) and gravitational lensing maps of rich clusters of galaxies – assuming axial symmetry (Zaroubi et al. 1998), is considered. Here we test the applicability of the method for realistic, numerically simulated galaxy clusters, v...

A method is described for mapping the plasma parameters nearby a hollow cathode using a high speed positioning system and a segment-shielded electrostatic probe. Contour maps of plasma density, plasma potential, and electron temperature are presented for wide ranges of discharge current (2 20 A) and xenon flow rate (1.5 – 4.5 sccm). The contour maps are constructed from the analysis of 320 I-V ...

Highly purified axial filaments have been prepared from the spirochete Treponema zuelzerae, which possess a fine structure similar to the "beaded" form of bacterial flagella. The preparations consist largely of protein but also contain small amounts of hexose (less than 1%). The buoyant density of these filaments is 1.29 g/cm(3). At pH 4.3, in the presence of 4 m urea and 10(-3)m ethylenediamin...

OBJECTIVE Here, we retrospectively investigate the value of voxel-wisely plotted diffusion tensor-derived (DTI) axial, radial and mean diffusivity for the early detection of malignant transformation (MT) in WHO II glioma compared to contrast-enhanced images. MATERIALS AND METHODS Forty-seven patients underwent brain magnetic resonance imaging follow-up between 2006-2014 after gross-tumor rese...

A general method of deprojecting two-dimensional images to reconstruct the three dimensional structure of the projected object – specifically X-ray, Sunyaev-Zel'dovich (SZ) and gravitational lensing maps of rich clusters of galaxies – assuming axial symmetry (Zaroubi et al. 1998), is considered. Here we test the applicability of the method for realistic, numerically simulated galaxy clusters, v...

PURPOSE Adaptive optics scanning laser ophthalmoscopy (AOSLO) under optimized wavefront correction allows for routine imaging of foveal cone photoreceptors. The intersubject variability of foveal cone density was measured and its relation to eye length evaluated. METHODS AOSLO was used to image 18 healthy eyes with axial lengths from 22.86 to 28.31 mm. Ocular biometry and an eye model were us...