ず、 ... (cause / reason, parataxis)
Usage
Vないform ~~ない~~ + ず
indicates a cause or reason. It is the same as [-なくて、...] but is used more in writing
[Xず, Y] can also be used to juxtapose clauses or phrases
Examples
子供の熱が[下がらず/下がらなくて]、心配しました
The child's temperature didn't come down, so I was worried。
田中さんは今月酋長せず、来月出張することになりました。
Mr. Tanaka isn't going away on business this month; he is go next month instead