WASHINGTON (Reuters) - A growing percentage of scientists and engineers in the United States come from other countries, the National Science Board reported on Wednesday. While saying it was not necessarily alarming to have foreign-born scientists working in the United States, the Board said the government should look at ways to train more citizens in these fields. The board, appointed to advise the federal government, used National Science Foundation figures taken from Census estimates of foreign-born workers. It found that foreign-born workers with bachelor's degrees represented 17 percent of all science and engineering positions held by people with bachelor's degrees,...