About: http://webisa.webdatacommons.org/353446764

Property	Value
http://www.w3.org/1999/02/22-rdf-syntax-ns#type	http://www.w3.org/ns/prov#Entity
http://www.w3.org/ns/prov#value	Using the code you posted, the selected category's ID is available in the $_REQUEST, you can check that ID against your products category in the default_content filter and add content if there is a match:
http://www.w3.org/ns/prov#wasQuotedFrom	stackexchange.com