In 1924, Spemann and Mangold performed one of the most important experiments in the history of embryology: they showed that transplantation of the dorsal lip of the blastopore of an amphibian embryo into the ventral side of a host embryo of a differently-pigmented species can induce a well organized ectopic axis derived mainly from cells of the host [1].
We considered a simple model organ organized along a single axis, in which cell proliferation pushes cells away from the niche and in which cells speed up in their cell cycle as their distance to the niche increases – but leave the cell cycle and differentiate after reaching a threshold distance (set to three cell rows for illustration purposes in Fig. 2).
Organizing space around an axis harks back to Persian paradise garden traditions, Mr. Smith said, and the resulting triangular patterns were considered sacred geometry.
In Figure 1a, an initial dataset is presented, organized by X-axis (columns) and Y-axis (rows); both axes are alphanumerically ordered.
In the Time Division Multiple Access (TDMA) scheme, radio resources are time slots (MacSlot objects) that follow each other on the time axis, organized in a MAC frame (MacFrame object).
Four identical subunit models were organized around the axis of K+ conduction by superposition of 188 backbone atoms of amino acids THR311-GLN357 onthethe segment THR373-ARG419 of Kv1.2.
As opposed to this, in most other bilaterians, Hox genes do show co-linearity and play a crucial role in organizing the antero-posterior body axis [ 4, 6, 7].
An area of organizing convection developed along the wave axis, and Dvorak classifications began on July 13, while the tropical wave was south of the Gulf of Tehuantepec.
In wing disc development, the Wingless (Wg) member of the Wnt family organizes the dorsal/ventral (D/V) axis, while BMPs are is required to pattern the anterior/posterior (A/P) axis (reviewed in [13]).
Obvious candidates for organizing the intrasegmental distribution of guidance cues along the antero-posterior axis are the segment polarity genes.
Phase difference estimates depend on how the information carried by a signal is organized on the temporal axis.
