The contrast-invariance of orientation tuning thus revealed showed the limitations of the purely feedforward model of orientation selectivity, initially proposed by Hubel and Wiesel (1962) [1], which predicts that, through an "iceberg effect", orientation tuning curves should widen when contrast increases (for a comprehensive account of the "iceberg problem" see [13], [14]).
Based on our institutional experience, the lack of T1-weighted tissue contrast at high fields is not correctible by simple adjustment of sequence parameters, and clinicians may increasingly depend upon the gadolinium-infused MRI contrast to widen the T1 contrast scale.
In contrast to the widening gap between the prospering south and the depressed north in the rest of the economy, the tourism industry north of the River Trent and west of the River Severn appears to be booming.
Breast cancer survival rose rapidly and significantly during the 1990s, and although the difference in survival between affluent and deprived women did not improve, at least it did not widen, in contrast to the widening deprivation gap in survival seen for most other malignancies (Coleman et al, 2004).
However, the increased background due to widening of the slit greatly reduces contrast in the image.
Drops with block copolymer showed widening even for shear strains exceeding 10, in contrast to bare drops, which first widened and then shrank.
This suppressed side-lobes of the PA beam, enhancing contrast-to-noise ratio (CNR) while widening a main lobe, and thus slightly degrading lateral spatial resolution.
Stuart Greif, vice president of the global travel practice at J. D. Power, said the contrast between the two airports illustrates the widening spread between the best and worst domestic airports.
By contrast, the split among Republicans appears to be widening.
By contrast, record increases in applications in recent years demonstrate a widening desire for higher learning and all that it promises in personal and professional terms.
