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.
1 Overactive bladder: The bladder muscle (detrusor) contracts involuntarily, causing some urine to leak out. 2  Detrusor overactivity is a common cause of urinary incontinence. 3  Hematuria: Blood in the urine. 4  Hematuria may be benign, or may be caused by infection or a serious condition like bladder cancer.uring urination, the bladder muscles contract, and two sphincters (valves) open to allow urine to flow out. Urine exits the bladder into the urethra, which carries urine out of the body. Because it passes through the penis, the urethra is longer in men (8 inches) than in women (1.5 inches).