|
Author Question: A 5.0-kg mass sits on the floor of an elevator that has a downward acceleration of 1.0 m/s2. On top ... (Read 6837 times) |
As the western states of America were settled, pioneers often had to drink rancid water from ponds and other sources. This often resulted in chronic diarrhea, causing many cases of dehydration and death that could have been avoided if clean water had been available.
Vaccines prevent between 2.5 and 4 million deaths every year.
More than nineteen million Americans carry the factor V gene that causes blood clots, pulmonary embolism, and heart disease.
When blood is exposed to air, it clots. Heparin allows the blood to come in direct contact with air without clotting.
It is believed that the Incas used anesthesia. Evidence supports the theory that shamans chewed cocoa leaves and drilled holes into the heads of patients (letting evil spirits escape), spitting into the wounds they made. The mixture of cocaine, saliva, and resin numbed the site enough to allow hours of drilling.