一体 => …the heck; …in the world; …on earth N3
も構わず => without caring; without worrying about ~ N2
も[構「かま」]わず => Without considering A N2
Considering, Concerning
を契機に => as a good opportunity/chance to N2
Expected
を[機「き」]に => Use A as an opportunity N1
Time, Situation
を[契機「けいき」] => As a good opportunity A, (do) B N2
Information, Report
をきっかけに/を契機に => with… as a start; as a result of; taking advantage of N2