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.
Following are some important causes: Urinary tract causes: 1  A large sized stone in bladder can block the urine outflow and cause accumulation of urine in bladder.  Similarly prostate enlargement (Benign prostate hypertrophy, BPH) may obstruct the urethral passage and cause retention of urine with bladder distension.