Intestinal metaplasia is also a common in Barrett esophagus. It this condition it is the esophageal squamous epithelial cells that undergo metaplasia. Approximately, 60% of esophageal cancers diagnosed in the U.S. stem from focal intestinal metaplasia.
Ozone Emission Sources. Emissions contributing to ozone formation come from many areas. The main emission sources categories are: On-road - cars, trucks, and buses. Off-road - aircraft, locomotive,etc. Non-road - construction, agricultural equipment, etc. Point - cement and power plants.
The ozone layer or ozone shield is a region of Earth's stratosphere that absorbs most of the Sun's ultraviolet radiation. It contains high concentrations of ozone in relation to other parts of the atmosphere, although still small in relation to other gases in the stratosphere. The ozone layer contains less than 10 parts per million of ozone, while the average ozone concentration in Earth's atmosphere as a whole is about 0.3 parts per million. The ozone layer is mainly found in the lower portion