My objective in this article is to add evidence for the belief espoused above regarding the two elds of (i) signal processing and (ii) control and estimation. I focus here on the interaction of specialties from (i), i.e., adaptive ltering, and (ii), i.e., adaptive identi cation and control. For evidence, I use three basic communication systems applications of adaptive ltering to evoke system id...

Hedgehog (Hh) proteins belong to a class of morphogens involved in many biological processes during embry-onic development; they are relatively silent during normal adult life although they may be recruited postnatally in re-sponse to tissue injury. Three secreted proteins have been identified: Sonic hedgehog (Shh), Desert hedgehog and Indianhedgehog. The interaction of Hh ligand wi...

Retinoids, a group of natural and synthetic analogues of vitamin A (retinol), modulate the differentiation of many cell types. Retinoids are also used for the prevention and treatment of cancer. The actions of retinoids are generally mediated by the retinoic acid receptors (RARs A, B, and ;) and the retinoid X receptors (RXRs A, B, and ;). One of the RARs, RARB, is expressed at reduced levels i...