A region crossing change at a region of a spatial-graph diagram is a transformation changing every crossing on the boundary of the region. In this paper, it is shown that every spatial graph consisting of theta-curves can be unknotted by region crossing changes.

中文翻译：

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空间θ曲线上的区域交叉变化

空间图的区域上的区域交叉变化是改变区域边界上的每个交叉的变换。在本文中，它表明每个由θ曲线组成的空间图都可以通过区域交叉变化来解开。