Word: oxygenate
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...temperature of nearly 1,000° F. and a thick atmosphere consisting largely of carbon dioxide, will not, says Berry, intimidate 21st century scientists. He notes that there is already a proposal to inject into the atmosphere of Venus hardy algae that feed on carbon dioxide. This would liberate oxygen, let heat escape from the planet's surface, and cause condensed water vapor to fall as rain. Oceans would form, plants could take root and grow, and Venus would be ready for colonizers from earth...
After 2½ years of controversy, the nation's first peacetime wage-price controls died last week, leaving disillusion and double-digit inflation in their wake. Almost immediately, prices began to scoot higher on a wide range of goods, including cars, light bulbs, liquid oxygen, some air-conditioning equipment and those basic materials, steel and copper...
Scientists have long believed that the irreversible damage caused by strokes results from cutting off oxygen to brain tissues that can survive only minutes without it. Now two neuroscientists have offered a more intricate theory that could explain some little-understood symptoms of strokes. It could also lead to treatments that could minimize the effects of strokes, which kill more than 200,000 Americans a year...
...caused by imbalances in the brain's neurotransmitters, the chemicals that carry nerve impulses from one neuron, or brain cell, to another. The doctors base their theory on experiments in which Neurosurgeon Zervas produced massive strokes in 13 monkeys by cutting off blood flow-and thus oxygen-to the left sides of their brains. Examining the brains afterward, he and Wurtman found that there were dramatic changes in the levels of dopamine, a substance that transmits nerve impulses among the brain cells that help coordinate movements. The amount of this chemical in the left halves of the brains...
This discovery was the first proof that neurotransmitter levels change following a cutoff of blood to the brain; it forms the basis of the Wurtman-Zervas theory. The two neuroscientists speculate that cells starved of oxygen as the result of strokes die and allow their stored dopamine to escape. Dopamine is normally released only in minuscule amounts, and a sudden flood of the chemical can be lethal. Excess dopamine can cause nearby blood vessels to contract, cutting off oxygen to neighboring cells and thus spreading the stroke damage. After the flood has subsided, there is a serious shortage...