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Students earn spot to compete in International Science and Engineering Fair
By Alex Bridges - email@example.com
STEPHENS CITY -- Projects on pesticide dangers and measuring the Earth with a sundial earned a pair of Sherando High School students spots at this May's International Science and Engineering Fair in Los Angeles.
This marks the second year in a row both students went on to the competition after winning the regional fair held at James Madison University.
"There are so many people," Holly Peterson, a 16-year-old junior, said at the school on Friday. "It's going to be intimidating actually, but I'm going mostly for the experience rather than trying to win the whole thing, 'cause it's huge."
Holly and fellow fair winner Christina Lee, a 15-year-old sophomore, both said they enjoy the sightseeing during the fair as well as meeting the other participants and seeing their experiments.
Christina conducted an experiment to see how pesticides and a fatty acid affected regeneration in flatworms called planaria. She used household pesticides to determine their impact on flatworm specimens. The project involved cutting off parts of the flatworm that normally grow back. Christina exposed the flatworms to chemicals that are neurotoxic to aquatic life and examined the specimens in petri dishes through a microscope.
"I was interested in how it would affect the regeneration of their eyespots as well as the nervous system and see if it had any long-term effects," Christina said. "Then I used DHA [Docosahexaenoic acid, an omega-3 fatty acid] to compare how something that's supposed to aid regeneration would look against something that hinders it, along with the control."
Christina took inspiration from her rural neighborhood, with its farms and home gardens.
"Store-bought pesticides are regulated, so if you don't follow the regulations on the back which are actually federal law," Christina said.
"Then if these pesticides wash into our groundwater, how could it possibly affect us if we use the planaria as a simulation."
The specimens have "dulled chemoreceptors," similar to human sense of smell or taste, so they weren't as sensitive to the chemical stimulus around them, Christina said.
"I found that it supported that we really need to follow the label on the back of the bottle, the federal law, and it encourages people to go with professionals for larger jobs in exterminating pests in their house as well as treating the lawns," Christina said.
"Next year, I want to see how it affects their [plenaria] learning because they can actually retain memory."
Holly decided to calculate the Earth's diameter. Holly built two, identical sundials using small, round, wooden tables and a piece of masonite board cut to the specific size and angle needed as the gnomon.
The Greek mathematician, Eratosthenes, used a sextant and angles to solve for the diameter around 240 B.C. Holly's calculation involved proportions using the distance between two cities over the time it takes a shadow to hit one city to the next. Her father had one sundial in Florence, Ky., while Holly stayed in Stephens City. The two spoke over the telephone as she conducted the experiment.
"The coolest part of that experiment is, when I solve for that proportion, I solve for it at 39 degrees and I want to get the diameter of the equator of the Earth so I have to mathematically compensate for that," Holly said.
Her result: 11,784 kilometers and 7.62 percent off from the accepted value, she said.
Holly has no problem being called a nerd.
"If you get excited about going to the science fair, you are a nerd," she said.