By Dan Weil A range of investments can help investors cope with the lessened effectiveness of a 60/40 portfolio. The market has been full of talk about stagflation — low growth combined with high inflation — for months, and the Russia/Ukraine war has only increased concern about it. Strategists at Goldman Sachs cite several ominous signs. The U.S. 10-year break-even rate, a measure of inflation expectations, has reached its highest level since the 1990s, while real yields remain near their lows, they note in a commentary. Low real yields can be a sign of high inflation and slow growth. “There …