There is significant geomorphologic evidence for the past presence of longitudinally widespread, latitudinally zoned deposits composed of ice-rich material at the northern and southern mid latitudes on Mars (lobate debris aprons, lineated valley fill, concentric crater fill, pedestal craters, etc.). Among these features, pedestal craters (Pd) are impact craters interpreted to have produced a pr...

[1] Since their discovery, Martian pedestal craters have been interpreted as remnants of layers that were once regionally extensive but have since been mostly removed. Pedestals span from subkilometer to hundreds of kilometers, but their thickness is less than ∼500 m. Except for a small equatorial concentration in the Medusae Fossae Formation, the nearly exclusive occurrence of pedestal craters...

0019-1035/$ see front matter 2011 Elsevier Inc. A doi:10.1016/j.icarus.2011.03.029 ⇑ Corresponding author. Fax: +1 401 863 3978. E-mail address: [email protected] (S.J. Kadi An outstanding question in Mars’ climate history is whether or not pedestal craters represent the armored remnants of ice-rich paleodeposits. We address this question using new high-resolution images; in a survey of sev...

PURPOSE The purpose of this study was to evaluate the properties of foveal temporal integration in patients with retinitis pigmentosa (RP) within the framework of contrast processing by the magnocellular (MC) and parvocellular (PC) pathways. METHODS Temporal integration functions were measured in eight patients with RP whose visual acuities ranged from 20/25 to 20/63. Contrast thresholds were...

A comparison of ASDEX Upgrade (AUG) discharges performed with carbon and the full tungsten wall shows that the pedestal performance at low triangularity is not altered without gas puffing. The pedestal electron pressure is the same for both wall materials as is the confinement. With the tungsten wall the natural density is higher even without an additional gas puff. In typical operation with ga...

The pedestal effect is the improvement in the detectability of a sinusoidal grating in the presence of another grating of the same orientation, spatial frequency, and phase-usually called the pedestal. Recent evidence has demonstrated that the pedestal effect is differently modified by spectrally flat and notch-filtered noise: The pedestal effect is reduced in flat noise but virtually disappear...

High-resolution quadrature reflectometer measurements of density fluctuation levels have been obtained on DIII-D for H-mode edge pedestal studies. Initial results are presented from the L–H transition to the first ELM for two cases: (i) a low pedestal beta discharge, in which density turbulence in the pedestal has little change during the ELM-free phase, and (ii) a high pedestal beta discharge ...

Previous studies have shown that detection of a red-green test pattern, such as a spot or grating, may be facilitated two to three times by a suprathreshold luminance pedestal of the same shape. We measured facilitation between the red-green (RG) and luminance (LUM) detection mechanisms using sine and square-wave gratings. Facilitation of RG by luminance pedestals was 3-fold for in phase sine-w...

The vernier judgment is commonly thought of as discriminating the displacement of a portion of a pattern. However, we have found it revealing to consider vernier stimuli in another light; as the composite of a test pattern superimposed on a masking pedestal. The pedestal is the pattern with zero spatial offset, and the test pattern is the luminance distribution which, when added to the pedestal...