Assistant principals aid the principal in the overall administration of the school. Some assistant principals hold this position for several years to prepare for advancement to principal jobs; others are career assistant principals.n larger school systems, a principal is often assisted by someone known as a vice-principal (Republic of Ireland: deputy principal) or assistant principal.
Causes. Pressure on the bladder during delivery is the main cause of a ruptured bladder, although a weakness in the bladder wall may make it susceptible to a rupture. In older horses, a ruptured bladder may be caused by an accident or related to a urinary obstruction.
The most frequent cause of acute cystitis is an infection of the bladder caused by the bacteria Escherichia coli. The bacteria enter the urethra and then travel to the bladder. Once in the bladder, the bacteria stick to the bladder wall and multiply. This leads to inflammation of the tissue lining the bladder.