Pesticide runoff impacts salmon recovery
WASHINGTON, Dec. 21 (UPI) -- Reducing pesticide runoff from farms and homes could speed the recovery of wild salmon populations in the western United States, biologists said.
Even short-term, seasonal exposure to pesticides may limit the growth and size of wild salmon, whose numbers have been declining for years, said David Baldwin of the National Oceanic and Atmospheric Administration.
Baldwin's team used existing data on the impact of common pesticides on salmon to devise a computer model that calculated productivity and growth rate.
One scenario predicted that salmon not exposed to pesticides would see a 523-percent increase in numbers over 20 years when compared with salmon exposed to pesticide levels found today in rivers and basins, NOAA said in a release Friday.
Pesticides have been found to reduce the activity of acetylcholinesterase, an enzyme in the salmon brain that causes them to feed less when exposed to pesticides.
People can trick mind to do hated things
CHICAGO, Dec. 21 (UPI) -- People tend to approach pleasure and avoid pain, but humans can trick the mind into doing beneficial things they don't like, U.S. researchers suggest.
Aparna A. Labroo of the University of Chicago and Jesper Nielsen of the University of Arizona in Tucson say human inclination is to avoid -- or try to avoid -- anything immediately aversive even though it may be beneficial for us in the long term.
"We tend to infer that something is good based on the bodily sensation of approaching it or bad based on the sensation of avoiding it," the researchers say in a statement.
However, the authors demonstrate an approach often used to try to cure phobic patients -- asking them to mentally simulate approaching the objects they fear -- can also create more favorable evaluations of "yucky" products and behaviors.
The researchers offered study respondents a can of curried grasshopper -- not terribly popular among the participants -- and asked one group to simply evaluate it, a second group to mentally simulate physical avoidance of the product and a third to simulate physical approach toward the can.
"What was surprising was that merely simulating physical approach resulted in a more favorable evaluation of the product," the authors say in a statement. "One way for us to overcome aversions is to trick our minds."
The findings are published in the Journal of Consumer Research.
Vaccine blocks malaria transmission
TOKYO, Dec. 21 (UPI) -- A nasal vaccine that blocked transmission of malaria from mice to mosquitoes someday could prevent malaria in people, scientists in Japan said.
The experimental vaccine, which contained parasite antigens, blocked the ookinete-to-oocyst phase in the malarial life cycle in which the malarial parasite is fertilized in the mosquito's body, the scientists wrote in the December issue of the journal Infection and Immunity.
Mosquitoes that stung and sucked blood from the nasally vaccinated mice were unable to pass malaria to other living beings because the fertilization cycle had been interrupted.
Children in developing countries often are at high risk of infection and death from Malaria. Antimalarial drugs and insecticide-treated bed nets have reduced the rate of malaria, but vaccines are needed for eradication of the infectious disease, the American Society for Microbiology said.
'Sexy' orchids pollinate more efficiently
NAPLES, Italy, Dec. 21 (UPI) -- Orchids that use sexual trickery to lure insects are more efficient in the transfer of pollen to another orchid, scientists in Italy said.
Scientists at the University of Naples Federico II studied 31 orchids, including some that produced flowers that looked or smelled like female insects and attracted male insects who collected pollen when they attempted to mate.
The orchids that used sexual deception had a higher rate of pollen transfer than orchids with multiple pollinators that provided a nectar or produced flowers that looked or smelled like nectar but offered no edible reward, researchers Salvatore Cozzolino and Giovanni Scopece said in a release Friday.
Specializing with one pollinator and using sex as a lure appears to make for a more efficient reproduction system, the researchers said in The American Naturalist.
"These results could provide new insights in the understanding of evolutionary shifts between generalized to specialized pollination strategies in flowering plants and that sexy orchids do it better," Scopece said.
