background contrast-induced nephropathy (cin) is one of the most important complications of angiography in patients with chronic kidney disease (ckd) or diabetes mellitus. the prevention of cin can decrease therapeutic costs and hospital stays. there is controversy in the literature over the preventive effect of statins on cin. objectives this study was designed to evaluate the preventive effec...

Previous studies have shown crowding alleviation when target and flankers similarity is reduced. However, in the case of contrast dissimilarity, the findings were inconsistent. This study examined the effect of stimulus contrast, particularly contrast dissimilarity, on both overall performance under crowded conditions and the critical distance-the spatial extent of crowding. To this end, we mea...

Monocular and binocular contrast sensitivity function for a range of spatial frequencies was measured in two groups of subjects with normal vision. Statistically significant differences in performance between the younger group (age 20-30 years) and the older group (age 50-87 years) were found at all spatial frequencies sampled between 0.40 and 19 X 25 cpd. In the age range 50-87 years there was...

Human infants' contrast thresholds for rectangular wave gratings differing in duty cycle were measured. The forced-choice preferential looking technique was used to estimate thresholds in fifteen 8- to 10-week old infants. The results indicated that contrast threshold varied systematically with duty cycle. Our findings were consistent with the predictions of a linear, multiple channel model and...

found that attention caused an increase in V4 neurons’ contrast sensitivity, as reflected in a leftward shift of the contrast–

We succeeded to develop a reference light source in the range of very low luminance using a double integrating sphere system, and calibrated a commercial spectrophotometer below 1 × 10−5 cd/m2 levels, which is 1/100 lower than the specified limit for measurement. And we improved measurements in the ultra low luminance range of displays using the calibrated commercial spectrophotometer and a dar...

current screening programme, indicate that such a cardiovascular screening programme appeals to and attracts a large audience. Persons attracted to such a programme seem to constitute a relatively healthy sample of the population, and this needs to be taken into account in the consideration of these results. However, the risk of developing future atherosclerotic disease in screened elderly men ...