This study was made feasible by an innovative design of a microfluidic device that is capable of generating large-scale molecular gradients with different levels of steepness in a microarray format, providing a high-throughput solution for investigating the dependence of neuronal chemotaxis on steepness of molecular gradient.
We considered different levels of steepness of the environmental cline by taking different values of k E. (8) k E = σ E 2 (σ G 0 2 + σ ∈ 2 ) σ G 0 2 being the total genetic variance observed within the initial population.
We systematically varied rk and from each thus obtained stimulus response curve of R i_cie ∗ -values extracted the Hill-coefficient h as a measure of steepness (see Methods).
Moreover, profiles analysis reveals a systematic geographic distribution of steepness indices and concavity in this area.
It was an almost perfect hill, with slopes all around that permitted skiing in all directions, at different degrees of steepness; skiers of almost any level would be able to get down safely.
Therefore, the GBR utility function should have a form of a step function, with the step steepness depending on the acceptable level of packet loss.
Furthermore, there is great variation in the detailed dynamical response as we have seen from Figures 5 and 7, with differences in total expression levels, steepness of response and timing of peak expression.
There was only a slight effect of the steepness of the environmental cline on the level of differentiation: Q ST = 0.7 when k E = 2 vs 0.62 when k E = 1.
We next tested whether the steepness of ravines was predictive of gene expression, beyond that which is possible using methylation level of the CGI alone, using a regression approach (see Methods).
This value reached a peak between generation 200 and 400, depending on the steepness of the environmental cline and the level of assortative mating.
Furthermore, the steepness also has strong leverage on the level of matching.
