A stronger U.S. dollar, weaker crude oil, generally weaker world grain prices and chatter about the lack of world demand for grains and oilseeds all served to press on futures prices. General Comments China remains the underlying topic for financial and commodity markets, but questions and concerns about it come when developed countries are already seeing slow growth or, in some cases, no growth at all. This is also a time when the economies of key developing countries like Brazil and Russia have turned negative. The late session failure of the U.S. stock market to hold onto its earlier rally sent a negative signal to other markets overnight. The Shanghai Composite Index opened down about 4 percent, but it was able to recoup most of that...