pav.rdf issues

[VladimirAlexiev]

$ riot --formatted=turtle pav.rdf  1>pav.ttl                                                                                   
WARN  :: [line: 2, col: 60] {W119} A processing instruction is in RDF content. No processing was done.

I think it's because of

<?xml-stylesheet type="text/xsl" href="owl2html.xslt.xml"?>

2. using empty namespace : for terms is not a good practice. Use the pav: namespace that is defined