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.
Ozone is a colorless gas found in the air we breathe. Ozone can be good or bad depending on where it occurs: Ozone occurs naturally in the Earth s upper atmosphere (the stratosphere), where it shields the Earth from the sun s ultraviolet rays. Ozone occurs naturally in the Earth s upper atmosphere (the stratosphere), where it shields the Earth from the sun s ultraviolet rays. 2  At ground-level, ozone is an air pollutant that can harm human health.