The specific cause of Parkinsonâs is unknown; however, medical experts believe the symptoms are related to a chemical imbalance in the brain caused by brain-cell death. Parkinson's disease is chronic (persists over a long period of time), and progressive (symptoms grow worse over time).arkinson's disease (or, simply, Parkinson's or PD) is the most common form of parkinsonism, a group of motor system disorders.
Quick Answer. Non-mandatory ZIP codes were introduced to the United States in 1963. Robert Moon, a postal inspector with the United States Postal Service, proposed the ZIP code system as early as 1944. Continue Reading.
The final two digits designated small Post Offices or postal zones in larger zoned cities. The ZIP Code began as scheduled. At first, use of the new code was not mandatory for anyone, but in 1967, the Department required mailers of second- and third-class bulk mail to presort by ZIP Code. The public and business mailers alike adapted well to its use. n.