Leukocytes in urine are not a dangerous condition, but they are a sign that you are suffering from an infection or damage. Leukocytes are white blood cells (WBC) that work with the immune system to defend against infectious disease. Damage to the kidneys, ureters, urethra or bladder can cause leukocytes to appear.
Empty vessels is a metaphor for a very shallow person whose thoughts and actions have no significant meaning. Such people are constantly talking or otherwise making noise in an attempt to get attention from other people. The more the person is ignored because he has no real input to give, the louder he will become.
This can often be a concern even if there is not a reduction in performance. The most common causes of noise are: 1. Cavitation: The jet unit is starved for water, and usually sounds like a rattle or a can of loose bolts in the back of the boat. Most likely a blocked intake grate.