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6 March 2014 1:04 pm ,
Vol. 343 ,
Antiretroviral drugs can protect people from becoming infected by HIV. But so-called pre-exposure prophylaxis, or PrEP...
Two studies show that eating a diet low in protein and high in carbohydrates is linked to a longer, healthier life, and...
Considered an icon of conservation science, researchers at World Wildlife Fund (WWF) headquarters in Washington, D.C.,...
The new atlas, which shows the distribution of important trace metals and other substances, is the first product of...
Early in April, the first of a fleet of environmental monitoring satellites will lift off from Europe's spaceport in...
Since 2000, U.S. government health research agencies have spent almost $1 billion on an effort to churn out thousands...
Magdalena Koziol, a former postdoc at Yale University, was the victim of scientific sabotage. Now, she is suing the...
- 6 March 2014 1:04 pm , Vol. 343 , #6175
- About Us
17 September 1999 8:00 pm
Today is the 322nd anniversary of the birth of Stephen Hales, an English clergyman known for his careful biological research, particularly on the physiology and growth of plants. Hales conducted a number of experiments between 1719 and 1725 in which he measured the pressure exerted by water moving through a plant. He attached a glass tube or a simple manometer filled with mercury to a cut stem surface and measured the change in height of the sap, which indicated root pressure. Hales made similar measurements of blood pressure in domestic animals, and by injecting chemicals, estimated blood-flow rates in organs. Hales also discovered the dangers of breathing "spent" air in enclosed spaces and invented a ventilator, which he introduced on ships and in hospitals and prisons.
[Source: Roy Porter, Ed., The Biographical Dictionary of Scientists (Oxford University Press, ed. 2, 1994).]