VANCOUVER — Canucks head coach Rick Tocchet says Thatcher Demko has "improved immensely the last 72 hours" as the all-star goaltender works his way back from a lower-body injury. The 28-year-old started Vancouver's playoff opener against the Nashville Predators, but hasn't suited up since. Vancouver has turned to third-string rookie Arturs Silovs in the post-season after backup Casey DeSmith was hurt in Game 3 against the Predators. Silovs, who is 4-3 in the playoffs with a .907 save percentage