I'm wondering about a sentence - article from The Independent (UK) - that I don't manage to make sense of, it's the following: "...Long-term US government interest rates - Treasury yields - also dropped, helped not only by the Fed's monetary stance but also by an insatiable demand from the Chinese and other emerging investors as they intervened to prevent their currencies from appreciating excessively." My question is: How the simple fact to buy a US government bond (albeit in large quantities for the Chinese investors) could be thought as a currency intervention to prevent its value appreciation ? My guess is, it may not be easy to explain that mechanism. But I would be glad to hear your thoughts about it. Thank you.