Sixth-Graders Get a 'BOOST' in N.C. Science Fair Competition

May 1, 2007

Two local sixth-grade girls--both advised by a graduate student “coach” from the Pratt School of Engineering--advanced through local and regional science fair competitions to compete at the state level this year.

“The girls are exceptionally bright and very motivated and their hard work was recognized, which was exciting,” said Dawn Pedrotty, the biomedical engineering graduate student who coached both state competitors.

The girls were two of 20 middle school students who gained valuable introductions to scientific research through a partnership, dubbed BOOST (Building Opportunities and Overtures in Science and Technology), among Duke University School of Medicine, Durham Public Schools and the North Carolina School of Science and Math aimed at fostering science education for under-represented minority students.

At the N.C. State Science Fair Competition, Maya Brown of Githens Middle School won an honorable mention in the Junior Division of Technology/Engineering and an award for best use of engineering measurements (grades 6-12) from the Society for the International System of Units for her project "How Dangerous is Riding a Bicycle Without a Helmet?" Tasmine Hughes of Durham School of the Arts won best Geological Project (grades 6-12) from The Society of Women Geologists for a project titled "How Healthy is the Soil?" (See project abstracts written by the girls below.)

The girls came up with their own scientific questions, Pedrotty said. Pedrotty then enlisted special assistance for Maya from Andre Loyd, a BME graduate student in Barry Myers’ lab who specializes in developing models of the pediatric skull and neck, who enabled laboratory testing and measurement of bicycle helmet performance.

“Maya produced really good data,” Loyd said. “Her project was essentially an advanced version of what college students in the class BME110: Introductory Biomechanics do. She tested real helmets.”

Loyd and Pedrotty have recently won awards of their own. Pedrotty won an Outstanding Woman Leader (OWL) Award from Duke’s Women in Science and Engineering (WiSE) for her leadership and community involvement, “including fostering homeless and sick kittens for the animal shelter, teaching diabetes education classes in Spanish at a local free medical clinic, participating as a Disaster Action Team captain for the Red Cross, and mentoring with Duke’s BOOST program.” Pedrotty is now completing her doctoral work in Nenad Bursac’s laboratory and will then continue on at Duke as a medical student next fall.

Loyd, now in his 4th year of graduate school, recently won third place and $1,000 in the National Society of Black Engineers technical paper writing contest for a report titled “Thresholding techniques for developing geometrically accurate pediatric skull and cervical spine.”

Other BOOST student winners advancing to the regional science fair included middle school students Paul Newman and Bajon Aatnite, coached by Pratt graduate students Rebecca Klinger and Billyde Brown respectively. Bajon won third place in the regional physical sciences category for his project titled "Failure Analysis of Ductile and Brittle Materials: Raising the Surface Energy."

How Dangerous is Riding a Bicycle Without a Helmet?

Abstract written by Maya Brown, Githens Middle School

One out of eight bicyclists with injuries suffers a traumatic brain injury (TBI) and two thirds of bicycle-related deaths were the result of TBI. Therefore, I wanted to study (1) if wearing a bicycle helmet reduces the impact force, reducing the chance of head injury, (2) if there is a difference between helmet foams, and (3) if you should discard your helmet after an accident, because the accident affects its ability to reduce force in future accidents.

I asked for foam samples from helmet companies, Bell and Brock, and purchased styrofoam. I tested these samples with an impact force testing apparatus (a weight with an accelerometer). I dropped the weight on the foam from 15cm and 30cm. I used a new piece of foam for each height and repeated the test at each height. I measured the difference in voltage from the accelerometer and converted voltage to acceleration with the calibration factor (9.34mV/g) specific to the accelerometer. Then I calculated the impact force.

My results showed that the impact force was greatly reduced by each type of foam. For example, the impact force at 15cm without helmet foam was 2,245N, and the average force with a bicycle helmet was 443N. Second, there was a difference between the types of foam. Brock foam had the lowest impact force. Finally, I found that you should throw away your helmet after an accident because the impact force increased during the second trial.

How Healthy is the Soil?

Abstract written by Tasmine Hughes, Durham School of the Arts

Soil forms slowly over time and is a limited resource. Accelerated erosion occurs as a result of mankind’s actions, leaving 80% of farm land eroded. Therefore, I wanted to study farm land in Durham, North Carolina, investigating (1) if erosion occurs and (2) the health of the soil. I visited Ganyard Farms and collected three soil samples from each field: pumpkin, corn and cotton.

To study if erosion occurs, I tested the soil composition, texture, and dispersibility. All of the soils from the farm had a composition of little clay, found in healthy soil, and mostly silt. Only corn soil had a healthy texture, and all of the soils dispersed in water, meaning they had low organic material and were eroded.

To test the health of the soil, I studied the three major nutrients in soil: nitrogen, phosphorus and potassium (NPK). I also studied the pH, which measures the acidity of the soil. I compared the farming soils to topsoil, fertilizer, and cow manure. Using a soil testing kit, I measured the levels of NPK and pH. Topsoil had a more neutral pH and was superior to the crop soils for all nutrients with two exceptions -- cotton had the same amount of potassium and pumpkin the same amount of phosphorous as topsoil. Overall, the crop soils had lower nutrient value than topsoil. Cow manure was the most nutrient rich.

In conclusion, I found that the crop soils in Durham were very eroded and less healthy than topsoil or cow manure.