Science in Brief
Can fish self-catch?
Scientists announced that they are testing a plan to train fish to catch themselves by swimming into a net when they hear a tone that signals feeding time.
If it works, the system could eventually allow black sea bass to be released into the open ocean, where they would grow to market size, then swim into an underwater cage to be harvested when they hear the signal.
The key question for fish farmers: How many fish will actually return, and how many will be lost to predators or simply swim away?
Saliva tests make diagnosis advance
U.S. researchers have identified all 1,116 unique proteins found in human saliva glands, a discovery that they said could usher in a wave of convenient spit-based diagnostic tests that could be done without the need for a single drop of blood.
As many as 20% of the proteins that are found in saliva are also found in blood, they said. The researchers hope saliva-based tests can be used to diagnose cancer, heart disease, diabetes and a number of other conditions, they report in the Journal of Proteome Research.
Like a genome, which lists all of the genes in an organism, a proteome is a complete map of proteins. While genes provide the instruction manual, proteins carry out the instructions by regulating cellular processes.
Folate can ease damage to hearts
Studies in rats show that high doses of folate, already used to prevent anemia in expectant mothers and birth defects, can blunt the effects of heart attacks, researchers from Johns Hopkins University say.
Giving the supplement for days before a heart attack or infusing it into the bloodstream during an attack reduced damage to the heart by 90%, they found in a study that will be published next month in the journal Circulation.
The researchers cautioned that people should not self-medicate until a clinical trial can be performed, but held out hope that the supplement could be used prophylactically in people at high risk for heart attacks and to treat victims.
Explorer gives up North Pole effort
British explorer Hannah McKeand has called off her attempt to become the first woman to reach the North Pole alone and unaided after falling through ice and injuring herself, her expedition manager say.
She set out from Canada's Ward Hunt Island on March 8 and by skiing, walking and swimming had hoped to take 60 days to cover the 478 miles to the pole, where temperatures can dip to minus 76 degrees Fahrenheit.
