Effect of retrace error on stitching coherent scanning interferometry measurements of freeform optics.

We report on the effect of retrace error during measurement of freeform optics using a commercial coherence scanning interferometer (CSI), and its in-built stitching capabilities. It is shown that measuring segments of freeform optics under non-null conditions, results in artifacts on the measured zone, similar to the Seidel aberrations. An experimental approach is used to quantify the induced aberrations based on the local slopes of the surface.

Low-Dose and Standard Overnight and Low Dose-Two Day Dexamethasone Suppression Tests in Patients with Mild and/or Episodic Hypercortisolism.

We previously reported on the lack of utility of the 1 mg overnight dexamethasone (DEX) test in mild and/or periodic Cushing's syndrome, as most patients with the condition suppressed to 1 mg DEX. It is possible that a lower dose of DEX as part of an overnight DEX test might be able to distinguish between mild and/or periodic Cushing's syndrome and those without the condition. The objective of the current study is to determine the sensitivity and specificity of a 0.

An Analog Macroscopic Technique for Studying Molecular Hydrodynamic Processes in Dense Gases and Liquids.

An analog, macroscopic method for studying molecular-scale hydrodynamic processes in dense gases and liquids is described. The technique applies a standard fluid dynamic diagnostic, particle image velocimetry (PIV), to measure: i) velocities of individual particles (grains), extant on short, grain-collision time-scales, ii) velocities of systems of particles, on both short collision-time- and long, continuum-flow-time-scales, iii) collective hydrodynamic modes known to exist in dense molecular fluids, and iv) short- and long-time-scale velocity autocorrelation functions, central to understanding particle-scale dynamics in strongly interacting, dense fluid systems. The basic system is composed of an imaging system, light source, vibrational sensors, vibrational system with a known media, and PIV and analysis software.

Fiber-based tools: material removal and mid-spatial frequency error reduction.

This paper details the feasibility of using fiber-based tools in a computer numerical control (CNC) environment to process optical materials and their ability to reduce the amplitude of pre-existing mid-spatial-frequency (MSF) surface errors. The work is motivated by earlier research conducted by the group exploring the ability of polymeric fiber-based tools to remove material from BK7 glass substrates. To evaluate these tools in a CNC environment, three tasks are explored.