What does Captain Kurotsuchi do to bring Nemu back to consciousness after her spirit particles have been absorbed by Szayelaporro?
I remember Ishida saying that it couldn't be aired. what exactly did he do?
You can watch the scene here.
The manga doesn't explicitly state what Mayuri did, and Uryuu makes the same remark.
However, it seems very likely that Mayuri fiddled with Nemu's "reset button"1, based on her moaning (see screenshot below), and his remark:
You can't even understand something that simple by looking at it?
He later derides Uryuu and Renji for reaching wrong conclusions, and calls them laymen who do not understand his technology. This suggests that he might have given Nemu something like a Tantric Massage. Laymen watching it in our world would reach exactly the same wrong conclusion.
I know the above theory is a speculation, but this is as much evidence I can provide to support it. I guess we won't know any more of what he did for the reason Uryuu mentions.
1 Sorry, I cannot be more explicit than that. I hope you know what I mean.