We propose a framework that brings together two major forms of default reasoning in Artificial Intelligence: applying default property classification rules in static domains, and default persistence of properties in temporal domains. Particular attention is paid to the problem of qualification, central in default reasoning and in any attempt to integrate different forms of this type of reasonin...

The Notch signaling pathway is critical in cell fate specification throughout development. In the developing wing disc, single sensory organ precursors (SOPs) are selected from proneural clusters via a process of lateral inhibition mediated by the Notch signaling pathway. The epidermal growth factor receptor (EGFR) pathway has also been implicated in SOP formation. Here, we describe the Drosoph...

Directed cellular movements are a universal feature of morphogenesis in multicellular organisms. Differential adhesion between the stationary and motile cells promotes these cellular movements to effect spatial patterning of cells. A prominent feature of Drosophila eye development is the 90 degrees rotational movement of the multicellular ommatidial precursors within a matrix of stationary cell...

Ever since Rick Shull asked me to prepare an essay of appreciation of Fred Keller, I have found myself putting it off. Somehow, something else was always needing to be done. Finally, I realized what was happening. I just did not want to face the fact that Fred was no longer with us. After a relationship that extended over more than 50 years, during which Fred taught me both pedagogically and by...

This interview with Fred Daum was carried out over email in March 2022.

year physiology, especially those papers emphasizing adaptive and integrative mechanisms. It is published 12 times a publishes original papers that deal with diverse area of research in applied