主節の内容を主張する根拠を述べる副詞節を導くための接続詞としてBecause、Since、AsとかGivenが一般的ですが、ちょっと工夫してMindful ofも使ってみましょう。前にBeingが省略されていると考えれば文法的には分詞構文と考えたほうがわかりやすいかもしれません。
Mindful of the sharp downturn in worldwide auto sales, Japanese carmakers are revising their business plans one after another with production cuts and postponement of investment plans both at home and abroad.
Mindful that this wording might hurt his feelings, I rephrased the sentence.
Mindful of the vital importance of calcium, she takes a daily calcium tablet.