If someone with HIV is diagnosed with one of these opportunistic infections (even if the CD4 count is above 200), he or she is said to have AIDS. AIDS usually takes time to develop from the time a person acquires HIV--usually between 2 to 10 years or more.
It has been thought that the wheel was invented in 8000 B.C but the oldest discovered wheel dates back to 3500 B.c. It was discovered in Mesopotamia (nowadays in Iraq). Below are the timelines of wheels and its usage in different era.
From tiny watch gears to automobiles, jet engines and computer disk drives, the principle is the same. Based on diagrams on ancient clay tablets, the earliest known use of this essential invention was a potters wheel that was used at Ur in Mesopotamia (part of modern day Iraq} as early as 3500 BC.The first use of the wheel for transportation was probably on Mesopotamian chariots in 3200 BC.rom tiny watch gears to automobiles, jet engines and computer disk drives, the principle is the same. Based on diagrams on ancient clay tablets, the earliest known use of this essential invention was a potters wheel that was used at Ur in Mesopotamia (part of modern day Iraq} as early as 3500 BC.