Search results for "Contrast"
showing 10 items of 1162 documents
Correction of vesicoureteral reflux: where do we stand?
2004
Purpose of review Newer techniques of molecular biology allow us to gain a better understanding of the molecular mechanism of primary urinary reflux. In recent years, diagnostic tools and treatment options for vesicoureteric reflux have dramatically changed. In this review, we want to focus on genetics, molecular biology, histology, clinical findings, diagnostic tools and newer surgical techniques for the treatment of vesicoureteric reflux published between 2003 and March 2004. Recent findings Recent findings have demonstrated that the renin-angiotensin-aldosterone system does not seem to be responsible for the development of primary vesicoureteric reflux. Echo-enhanced ultrasound with cont…
Intra-visual conflict in visually induced motion sickness
2011
Abstract Motion sickness (MS) can be a debilitating side-effect not just of sea travel, but also when immersed in video games or virtual environments (visually induced MS). To explore the impact of visual display parameters on motion sickness, we presented footage taken on an automobile race track to different groups of observers during three experiments. In Experiment 1, one group watched the movie wearing a head-mounted display (HMD) and a second group looked at a large projection screen with unrestricted view. Resolution and visual angle were equated. In contrast to common assumption, the projection screen produced significantly higher motion sickness scores than the HMD. To understand t…
Responses to eccentric rotation in two space-bound subjects
1993
Two subjects were rotated eccentrically in the manner described previously. In contrast to a normal control group, settings of a luminous line to the subjective vertical were almost unrelated to the gravitoinertial vector before, and totally so shortly after, space flight. Only 3 days postflight did a clear relation to the gravitoinertial vector re-establish itself in the one subject who actually flew. The correspondence became normal 5 days after the flight. Since there were no clinical abnormalities evident in the subjects, it is suggested that both subjects suppressed their vestibular information, presumably as an effect of vestibular deconditioning training before the flight. In additio…
Identifying critical incidents in naturalistic driving data: experiences from a promoting real life observation for gaining understanding of road use…
2013
The methodology of naturalistic driving observation aspires to observe the driver and his environment while driving in natural driving settings. It is of great importance in research on road safety as this method of observing road users eliminates the disadvantages of traditional methods like simulator studies or interviews. However, it produces vast such amounts of data and challenges data reduction and data analysis. Therefore automatic methods for filtering critical incidents based on thresholds for numerical data are often applied to select the data to be analysed. This study reports a small-scale field trial in Valencia, Spain, which was conducted within the promoting real life observa…
Il contrasto penalistico alla violenza sulle donne.
2014
L'articolo ricostruisce gli strumenti di contrasto penalistico alla violenza sulle donne.
The physiological basis for contrast opponency in motion computation in Drosophila
2021
This dataset contains traces (dF/F0) from in vivo two-photon calcium imaging from Tm1, tm2, Tm4, Tm9, CT1, and T5 neurons from responses to ONOFF fullfield flashes, ON and OFF bars, and moving sinewaves.
Liquid crystal goggles for vision science applications
2003
Spectral and switching characteristics of two manufacturer liquid crystal goggles are tested, and a contrast ratio for the computer display phosphors wavelengths is determined. Goggles are used in vision science experiments for random dot stereo stimuli phase separation. The human stereovision acuity and threshold was studied for case, when one eye random dot stereo stimulus simulated on the display is cotinuously blurred or the stimulus contrast is decreased.
<title>The perception of isoluminant coloured stimuli of amblyopic eye and defocused eye</title>
2008
In routine eye examination the visual acuity usually is determined using standard charts with black letters on a white background, however contrast and colour are important characteristics of visual perception. The purpose of research was to study the perception of isoluminant coloured stimuli in the cases of true and simulated amlyopia. We estimated difference in visual acuity with isoluminant coloured stimuli comparing to that for high contrast black-white stimuli for true amblyopia and simulated amblyopia. Tests were generated on computer screen. Visual acuity was detected using different charts in two ways: standard achromatic stimuli (black symbols on a white background) and isoluminan…
Analysis of the possible benefits of aspheric intraocular lenses: review of the literature.
2008
We reviewed recently published studies that analyzed the visual and optical quality in eyes with different spherical and aspheric intraocular lenses (IOLs). Recent studies focused on visual quality metrics, such as visual acuity and contrast sensitivity, under photopic and mesopic lighting conditions and optical metrics, such as wavefront aberrations, especially spherical aberration. The results in this review were used in an attempt to understand whether there is a visual and/or optical benefit of implanting aspheric IOLs over implanting spherical IOLs.
<title>Estimation of stereovision in conditions of blurring simulation</title>
2005
The aim of this study was to evaluate the simulation of eye pathologies, such as amblyopia and cataracts, to estimate the stereovision in artificial conditions, and to compare the results on the stereothreshold obtained in artificial and real- pathologic conditions. Characteristic of the above-mentioned real-life forms of a reduced vision is a blurred image in one of the eyes. The blurring was simulated by (i) defocusing, (ii) blurred stimuli on the screen, and (iii) occluding of an eye with PLZT or PDLC plates. When comparing the methods, two parameters were used: the subject's visual acuity and the modulation depth of the image. The eye occluder method appeared to systematically provide h…