Visualization with OpenGL: 3D made easy

This article addresses a freely available application programming interface (API) for three-dimensional graphics, known as OpenGL. This API bridges the gap between piles of raw data and extremely complicated three-dimensional animation in a way that requires only a few hours to learn. It is can be used for EM field visualization. In this article, we try to take most of the “leg-work” out of learning OpenGL, by presenting a tutorial that will get you started in the right direction. Some other interesting OpenGL-related technologies are also mentioned     

Detection of silent intervals between noises activating different perceptual channels: some properties of "central" auditory gap detection

This article describes four experiments on gap detection by normal listeners, with the general goal being to examine the consequences of using noises in different perceptual channels to delimit a silent temporal gap to be detected. In experiment 1, subjects were presented with pairs of narrow-band noise sequences. The leading element in each pair had a center frequency of 2 kHz and the trailing element's center frequency was parametrically varied. Gap detection thresholds became increasingly poor, sometimes by up to an order of magnitude, as the spectral disparity was increased between the noise bursts that marked the gap. These data suggested that gap-detection performance is impoverished when the underlying perceptual timing operation requires a comparison of activity in different perceptual channels rather than a discontinuity detection within a given channel. In experiment 2, we assessed the effect of leading-element duration in within-channel and between-channel gap detection tasks. Gap detection thresholds rose when the duration of the leading element was less than about 30 ms, but only in the between-channel case. In experiment 3, the gap-detection stimulus was redesigned so that we could probe the perceptual mechanisms that might be involved in stop consonant discrimination. The leading element was a wideband noise burst, and the trailing element was a 300-ms bandpassed noise centered on 1.0 kHz. The independent variable was the duration of the leading element, and the dependent variable was the smallest detectable gap between the elements. When the leading element was short in duration (5-10 ms), gap thresholds were close to 30 ms, which is close to the voice onset time that parses some voiced from unvoiced stop consonants. In experiment 4, the generality of the leading-element duration effect in between-channel gap detection was examined. Spectrally identical noises defining the leading and trailing edges of the gap were presented to the same or to different ears. There was a leading-element duration effect only for the between channel case. The mean gap threshold was again close to 30 ms for short leading-element durations. Taken together, the data suggest that gap detection requiring a temporal correlation of activity in different perceptual channels is a fundamentally different task to the discontinuity detection used to execute gap detection performance in the traditional, within-channel paradigm.     

Social support and coping strategies as mediators of adult adjustment following childhood maltreatment

Structural equation modelling (SEM) was used to examine whether coping efforts and social support mediate the long-term sequelae of child maltreatment. The hypothesized SEM fit the data well and indicated that the association between previous childhood sexual and physical maltreatment and current psychological adjustment appeared to be strongly mediated by social support and coping strategies. In this sample of 302 female and male university students, most of whom reported at least one episode of childhood maltreatment, perceived social support and ways of coping with earlier maltreatment appeared essential to an understanding of the relationship between childhood maltreatment and later adjustment.