Negation for Document Re-ranking in Ad-hoc Retrieval by Pierpaolo Basile, Annalina Caputo and Giovanni Semeraro.
Interesting slide deck that was pointed out to me by Jack Park.
On the “negation” aspects, I found it helpful to review Word Vectors and Quantum Logic Experiments with negation and disjunction by Dominic Widdows and Stanley Peters (cited as an inspiration by the slide authors).
Depending upon your definition of subject identity and subject sameness, you may find negation/disjunction useful for topic map processing.