BEGIN:VCALENDAR VERSION:2.0 PRODID:-//132.216.98.100//NONSGML kigkonsult.se iCalcreator 2.20.4// BEGIN:VEVENT UID:20251024T091704EDT-7723gU5VwL@132.216.98.100 DTSTAMP:20251024T131704Z DESCRIPTION:Title : Regulatory networks: searching for periodic orbits\nAbs tract : In cells\, proteins are produced by DNA sequences. The rate of pro duction is influenced by the presence of other proteins connected to the D NA sequence. We can represent such interaction by a regulatory network\, a directed graph where the edge i—> j exists if x_i affects the rate of cha nge of x_j. For biological reasons\, we expect x_i to appear in the rate o f change of x_j through a sigmoidal function\, H_{ij}.\nIn this talk\, we first approximate each sigmoidal function H_{ij} by a step function. Each step function is defined by three parameters and we expect the parameter s pace to be high dimensional. In such high dimensional space\, we want to d etermine which choice of parameters allow for oscillations in a given netw ork. For this goal\, we will use a combination of combinatorial tools and Morse graphs.\nOnce we have found parameters compatible with oscillations using step functions\, we want to discuss the stability of such oscillatio ns if the step functions are smoothened back into sigmoidals. For this\, w e will discuss tools developed in the context of machine learning. DTSTART:20200120T210000Z DTEND:20200120T220000Z LOCATION:BURN 1104\, Burnside Hall\, CA\, QC\, Montreal\, H3A 0B9\, 805 rue Sherbrooke Ouest SUMMARY:Elena Queirolo (Rutgers University) URL:/mathstat/channels/event/elena-queirolo-rutgers-un iversity-310191 END:VEVENT END:VCALENDAR