Adventures in Research
Hauling 60-plus pounds of geological gear up mountains. Purifying ancient marine shells for cutting-edge analysis. Rendering educational concepts into mathematical expressions. These professional-level adventures were the stuff of summer for three Bentley juniors.
Mike Ravisi, Greg Bucci and Eric Ndung’u signed on to help three Bentley faculty members conduct original research. The undertaking wins high praise from Dean of Arts and Sciences Dan Everett.
“Cross-cultural studies show one constant: People learn better by acting on knowledge than by passively receiving it,” he says. “The personal enrichment derived from creating new knowledge is never more life-changing than at the start of our intellectual career. Research experiences – even the most mundane – can alter the way that undergraduates will think for the rest of their life.”
“Going deep” has new meaning for Mike Ravesi and Greg Bucci since their research trip to the Colorado Front Range.
In July and August 2010, they helped Professor of Natural and Applied Sciences P. Thompson (Thom) Davis collect sediment from two alpine lakes and chips of boulders from glacial deposits known as moraines. The samples would help plumb the mysteries of climate change in the region over the past 12,000 years or so. The project is funded by the National Science Foundation and part of an ongoing collaboration between Davis and colleagues at Oregon State University.
The Bentley team’s first stop was Caribou Lake, where the researchers camped for five days to gather sediment cores and moraine samples. They did more coring over another three days at Upper Chicago Lake. At both sites, they had to time their sampling forays to dodge dangerous daily thunderstorms.
“It would have been too dangerous to core during a thunderstorm,” says Davis, citing factors such as high altitude, metal equipment, and work sites located in the middle of lakes.
For the nine-mile trek to the first site, they were able to use horses to pack in much of the gear. Without the equine assist for site No. 2, team members backpacked all their equipment on an uphill hike of 2.5 miles.
“There was no other way in.” says Bucci, whose majors are Managerial Economics and Liberal Studies, with a concentration Earth, Environment and Global Sustainability.
Coring was done one muddy meter at a time. “We’d stand on the raft and push a meter-long tube down into the lake bottom until it was filled with sediment,” Bucci explains. As the tube was pulled up, water pressure kept the silty stuff in place – for a while. “As soon as we broke the water line, the sediment could start to slip out.”
Plugging the bottom of the tube required split-second timing by the trio. They also had to apply more strength as each new sediment collection tube reached deeper into the lake bottom.
The mud was especially difficult to penetrate at Upper Chicago Lake, reports Ravesi, who combines his Liberal Students major with one in Computer Information Systems. “It was really cold during our last day, and we just needed to push through.”
But the reward is substantial: The tubes contain “a beautiful continuous record of 10,000 to 12,000 years of paleoclimate proxies,” observes Davis, who has long studied glacial deposits and lake sediments to interpret natural causes of climate change. “Understanding natural causes is a prerequisite for assessing the effects of human activity on the climate.”
Back on campus, he and the students are using radiocarbon dating to measure the ages of the lake sediment samples, while noting changes in the sediment’s organic carbon to illuminate climate shifts during the period. The moraine samples will undergo another type of analysis to determine their ages.
“I asked the students to fully engage in this effort, and they delivered,” Davis says of Ravesi and Bucci, who received stipends for their work. “Their willingness to push themselves physically and intellectually made all the difference. That’s what makes for professional scientific exploration.”
Solving a Glacial Mystery
Ravesi’s summer of exploration continued in a project with Rich Oches, associate professor of natural and applied sciences. The two have used cutting-edge analysis to determine the ages of marine fossils from the Boston Harbor Islands.
Their work takes aim at a tantalizing mystery involving glacial till: the jumble of boulders, sand and other material that glaciers collect while grinding across a landmass, and then drop as they melt. The 34 Harbor Islands were formed by glacial activity; some have two layers of glacial till.
The layers have generated a geological debate dating back to the 1850s, according to Oches. Each till may have been left by a separate glacier during two different ice ages, or both layers may have been sloughed off by the same glacier.
“A third possibility is that the lower till was created by multiple earlier advances of the ice,” explains the professor, who studies the Earth’s climate history as well as human and environmental response to climate changes over time.
Determining the ages of fossils from the two layers will point to when and how the tills were formed. That is the task that sent Oches and Ravesi to the Bentley science lab.
“We tested fragments of marine shells from the upper and lower glacial till units that make up the coastal cliffs of Peddocks Island and Long Island,” explains Oches. “The Harbor Islands are one of the only places in this region where we can access materials from as far back as 150,000 years.”
The testing strategy, which Ravesi helped to plan, required a painstaking process of cutting, cleaning and dissolving the fossil fragments. The result was a clear liquid of fossil amino acids, which Ravesi purified and sent for a 24-hour stay in the lab oven. The samples were then ready for high-pressure liquid chromatography (HPLC) tests.
“The project directly aligns with my interests in paleobiology,” notes Ravesi. “I appreciate that in a business school I can participate in such an in-depth science project.”
In September, Finance and Liberal Studies major Tim Witherell ’12 picked up the project to conduct the analysis. He, like Ravesi, is pursuing the Earth, Environment and Global Sustainability concentration of the Liberal Studies major. A student research assistantship from the Valente Center for Arts and Sciences supports Witherell’s work, which continues in the spring semester.
Was each till left by separate glaciers during two different ice ages? If so, fossils from the older layer could be 150,000 years old, while those from the younger till would clock in at about 20,000 years. The single-glacier theory, on the other hand, gains credence if shells from both tills are roughly the same age. Finally, fossils from different sections of the lower till that are widely scattered in age would suggest the till’s formation by “multiple earlier ice advances.” Results of the study are expected next summer.
Bio (Education) Feedback
Sometimes, research partners don’t have to travel farther than an Internet connection. Such was the case for science professor Fred Ledley and student Eric Ndung’u, who collaborated on two projects related to biology education.
For one study, Ndung’u dug into the Influenza Virus Resource, an extensive online database provided by the National Center for Biotechnology Information. He was out to test strategies for using the database in teaching.
“This collection contains genomic sequences of viruses ranging from the strains that caused the 1918 pandemic to the H1N1 ‘swine’ flu and the H5N1 ‘avian’ flu, which remains a potential threat,” explains Ledley. “Eric took the ball and ran with it.”
With deft precision, the Mathematical Sciences major grabbed gene and protein sequences from selected strains of virus, from which to construct evolutionary trees.
“His work demonstrated how the database could be used to develop and test hypotheses about the evolution of influenza originating from specific species, locations, and time periods,” says Ledley, who chairs the Natural and Applied Sciences Department. “This exercise can be used in human biology courses for non-science majors as part of a unit about influenza.”
He and Ndung’u chronicled the work in a co-authored paper published in the Journal of College Science Teaching.
For the other project, Ndung’u contributed to what could become a paradigm shift in how biology is taught.
“The rise of genomics has brought a landslide of new knowledge and dramatically changed biological thought,” says Naomi Wernick, a former adjunct assistant professor in the Natural and Applied Sciences Department who also worked on the project. “We wanted a read on how biology textbooks are presenting the relevant topics.”
Traditional education in biology, Ledley explains, introduces students to species, then moves to the smaller realms of organs, cells, and finally, molecular structures and reactions. But the genomic paradigm pivots that progression of knowledge. Students start small, learning first about gene sequences and activities, and influences on those activities; study then zooms out to the diversity of life and related topics such as evolution.
Knowing that the order in which concepts are presented affects student learning, Ledley and Wernick wondered: Do introductory textbooks reflect the modern genomics perspective? Or do they continue to present concepts in the traditional way? The study to find out was a perfect fit for Ndung’u.
“Professors look at educational materials one way. Students experience them from the other side – so Eric brings that perspective,” observes Ledley. “He also brings the ability to apply powerful mathematical tools that can pinpoint which topics are more often described in close proximity to each other.”
Ndung’u, who aspires to an actuarial career, embraced the exacting work of pulling terms such as “stem cells” from the indexes of more than 25 textbooks. These so-called meta-terms formed the backbone of the analysis. The goal was to map where the so-called meta-terms appeared in relation to each other within the books.
Working with Professor of Mathematical Sciences Dominique Haughton, Ndung’u analyzed statistical, self-organizing maps to visualize how the meta-terms are clustered in the textbooks as well as the order in which the terms are introduced. Within a few months, the analysis was complete.
“We found that many of the books present biology as it was taught 20 years ago,” Wernick reports, calling the results “a step toward correcting this state of affairs.”
The work is being submitted for publication in a science education journal, with Ndung’u as a coauthor – a rare achievement for an undergraduate.
“I loved these research projects,” he says. “I got to apply mathematical knowledge learned in the classroom to understand important issues and help others understand them better.”
Ledley has similar enthusiasm for the collaboration, noting that Ndung’u “contributed at a very sophisticated level” for both projects.
“While most of the conversation at Bentley is about business, students are first and foremost impressionable young adults who are offered the chance to engage in a wealth of academic and human endeavors,” he adds. “As participants in undergraduate research, students become partners with faculty not only in learning, but in the creation of knowledge.”