Definition of "adjust"

As the world's drug habit shows, governments are failing in their quest to monitor every London window-box and Andean hillside for banned plants. But even that Sisyphean task looks easy next to the fight against synthetic drugs. No sooner has a drug been blacklisted than chemists adjust their recipe and start churning out a subtly different one.

2013 August 10, “A new prescription”, in The Economist, volume 408, number 8848

But poverty’s scourge is fiercest below $1.25 (the average of the 15 poorest countries’ own poverty lines, measured in 2005 dollars and adjusted for differences in purchasing power): people below that level live lives that are poor, nasty, brutish and short.

2013 June 1, “Towards the end of poverty”, in The Economist‎, volume 407, number 8838, page 11