A hiatal hernia does not cause many symptoms by itself, but when a sliding hernia occurs, the abnormal location of the gastroesophageal (GE) junction above the diaphragm affects its function and stomach contents can reflux into the esophagus.
-You need to work on sentence structuring. For example, when you wrote, The immigration, as a decision maked by a person is an act that occurs, because of some factors especially in the under developed countries and the most importants causes or reasons are mainly social reasons, politic reasons and economic reasons..
By equalizing immigration policies, the act resulted in new immigration from non-European nations, which changed the ethnic make-up of the United States. In 1970, 60% of immigrants were from Europe; this decreased to 15% by 2000.merican immigration history can be viewed in four epochs: the colonial period, the mid-19th century, the start of the 20th century, and post-1965. Each period brought distinct national groups, races and ethnicities to the United States.