In the US legal system, judicial decisions create legal precedents that guide judges in deciding similar future cases. The decisions of the highest court in a jurisdiction create mandatory precedent that must be followed by lower courts in that jurisdiction.
Usually a bubble echo is looking for an opening between the top 2 chambers in the heart. During a regular echo, which is totally noninvasive, they inject some saline with a small amount of air into an IV. That is the only invasive part of the test. They then look at the screen and see where the bubbles go. In a negative study, they all go over to the left side of the heart. In a positive study, some don't go to the left side, indicating a possible connection or small hole in the heart. It is totally painless; I have had 2 done.
The bubbles seen when boiling water is not a chemical change. That's a physical change. So bubbles can indicate a chemical change but sometimes it just a liquid that's boiling or some dissolved gases coming out of solution. Lab 4 Experiment 1: Physical and Chemical Properties. Physical and Chemical Changes.