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.
Low level ozone (or tropospheric ozone) is an atmospheric pollutant. It is not emitted directly by car engines or by industrial operations, but formed by the reaction of sunlight on air containing hydrocarbons and nitrogen oxides that react to form ozone directly at the source of the pollution or many kilometers down wind.