Neutrophils are the most common type of white blood cell, comprising about 50-70% of all white blood cells. They are phagocytic, meaning that they can ingest other cells, though they do not survive the act. Neutrophils are the first immune cells to arrive at a site of infection, through a process known as chemotaxis.
One of the basic theories stipulates that increasing interest rates raise consumers' and manufacturers' costs, which, in turn, reduces the amount of time and money people spend driving. Less people on the road translates to less demand for oil, which can cause oil prices to drop.
The Federal Reserve has held interest rates at super low levels for years in an effort to bolster the economy, but it is expected to raise rates for the first time in seven years this week. AUDIE CORNISH, HOST: In December of 2008, the Federal Reserve cut interest rates to near zero to combat the financial crisis and the Great Recession. This Wednesday, exactly seven years later, the Fed is on track to increase interest rates for the first time since.