As Nature has pointed out before, there are some legitimate concerns about how science prizes—both new and old—are distributed.
主干:there are some legitimate concerns
介词短语作后置定语:about how science prizes—both new and old—are distributed.修饰concerns。
翻译:正如《自然》杂志以前已经指出的那样,对于科学奖项——新设的和原有的——如何分配,存在某些忧虑是合理的。