TY JOUR TI Digital ecosystem model: Russian b2c market leaders and their adaptation to modern challenges KW digital ecosystems KW import substitution KW artificial intelligence KW online economy KW sanctions KW geopolitical changes KW cloud technologies KW Internet of Things KW cybersecurity KW blockchain KW personalization KW Russian market JO JOURNAL OF MONETARY ECONOMICS AND MANAGEMENT AU Guz, A.R. AU Stefanova, N.A. PY 2025 IS 0 PB ITBO University