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Author Question: A discrete-event simulation reviews the status of the system periodically, whether or not an event ... (Read 52 times) |
For about 100 years, scientists thought that peptic ulcers were caused by stress, spicy food, and alcohol. Later, researchers added stomach acid to the list of causes and began treating ulcers with antacids. Now it is known that peptic ulcers are predominantly caused by Helicobacter pylori, a spiral-shaped bacterium that normally exist in the stomach.
In the United States, an estimated 50 million unnecessary antibiotics are prescribed for viral respiratory infections.
More than 2,500 barbiturates have been synthesized. At the height of their popularity, about 50 were marketed for human use.
Vaccines cause herd immunity. If the majority of people in a community have been vaccinated against a disease, an unvaccinated person is less likely to get the disease since others are less likely to become sick from it and spread the disease.
In the United States, there is a birth every 8 seconds, according to the U.S. Census Bureau's Population Clock.