SEVERAL years ago, few travel books ever mentioned Yangpu District in the context of exploring glitzy Shanghai. That’s understandable considering the fact that this cradle of Shanghai’s modern industry wore down into a “rust belt” when it fell through the cracks of economic and industrial activity begun in the 1980s. Old legacies and new endeavors are legitimizing its new claim to an old economic birthright, and it’s doing it all in style – again – in a transformed, knowledge economy.