Word: nitrogen
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Dates: during 1990-1999
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...past, efforts to discover drugs for use in the brain have been governed by the assumption that any such chemical compound needed to contain a nitrogen atom. As a result, all current drugs which target the brain have nitrogen atoms...
...study by Bertha K. Madras, associate professor of psychobiology at Harvard Medical School, reveals that nitrogen is not a required element of drugs working in the brain...
Madras and her co-authors found a group of drugs without nitrogen that recognizes the same molecular targets as nitrogen-containing drugs...
Unhappily for reefs, humans upset the balance between corals and their competitors in many ways. Consider the erosion that accompanies deforestation and agriculture. No longer restrained by tree roots, tons of soil laden with nitrogen and phosphate washes into rivers and then sweeps into the sea, forming a muddy plume that may be hundreds of miles long. As this nutrient-rich water flows over a reef, it stimulates the growth of all kinds of algae--including the microscopic diatoms and dinoflagellates that nourish such reef animals as the crown-of-thorns starfish. In recent years hordes of these coral-devouring...
...Still, untold trillions of charged particles manage to leak through. Some are trapped to form the Van Allen radiation belts that surround the earth. Others spiral down the magnetic field lines that project from the North and South poles. Energy unleashed by this disturbance excites atoms of nitrogen and oxygen, which in turn emit pulses of colored light. The result: an aurora...