Light curves produced by the Kepler mission demonstrate stochastic brightness fluctuations (or "flicker") of stellar origin which contribute to noise floor, limiting sensitivity exoplanet detection and characterization methods. In stars with surface convection, primary driver these variations on short (sub-eight-hour) timescales is believed be convective granulation. this work, we improve exist...

PURPOSE To determine retinal vessel diameter variations in response to neuronal activity induced by diffuse luminance flicker. METHODS The diameter of retinal arteries and veins was measured in 9 normal subjects by computer analysis of fundus pictures taken in monochromatic light under normal conditions of illumination and after 1 min of sinusoidally varying diffuse luminance flicker at 10 Hz...

1. We have studied the sensitivity of macaque retinal ganglion cells to sinusoidal flicker. Contrast thresholds were compared for stimuli which alternated only in luminance ('luminance flicker') or chromaticity ('chromatic flicker'), or which modulated only the middle- or long-wavelength-sensitive cones ('silent substitution'). 2. For luminance flicker, the lowest thresholds were those of phasi...

PURPOSE In the retina there is general agreement that blood flow adapts in response to different conditions of light and darkness including diffuse luminance flicker. By contrast, regulation of choroidal blood flow in response to different light conditions is still a matter of controversy. Thus, we investigated the effect of diffuse luminance flicker on choroidal and optic nerve head blood flow...

Flicker modulation sensitivity measurements made on high intensity orange steady backgrounds indicate that signals from short-wavelength sensitive cones (S-cones) have access to two pathways. At low S-cone adaptation levels the frequency response falls quickly with increasing frequency, but at higher adaptation levels it extends to much higher frequencies. At these higher S-cone adaptation leve...

Lampreys and hagfishes are the sole extant representatives of the early agnathan (jawless) vertebrates. We compared retinal function of fully metamorphosed, immature Mordacia mordax (which are about to commence parasitic feeding) with those of sexually mature individuals of its non-parasitic derivative Mpraecox We focused on elucidating the retinal adaptations to dim-light environments in these...

The ability to perceive a certain number of visual stimuli per unit of time has been found to differ significantly between hypothyroid patients and normals (3), between oMer and younger persons (1, 2), between fatigued and rested truck drivers (5), etc. In all such cases, the number of light-dark cycles per second at which a physically intermittent light was just perceived as a steady light was...

PURPOSE. To use the 25-item National Eye Institute Visual Function Questionnaire (VFQ-25) to evaluate vision-related quality of life (VR-QOL) in patients with pituitary adenoma who undergo transsphenoidal surgery. METHODS. The VFQ-25 was self-administered by 74 patients with pituitary adenoma before and 3 months after surgery. Pre- and postoperative clinical data were collected, including age, ...

Hormones and neurotransmitters are released through fluctuating exocytotic fusion pores that can flicker open and shut multiple times. Cargo release and vesicle recycling depend on the fate of the pore, which may reseal or dilate irreversibly. Pore nucleation requires zippering between vesicle-associated v-SNAREs and target membrane t-SNAREs, but the mechanisms governing the subsequent pore dil...