Studying these cells could lead to new treatments for diseases ranging from gastrointestinal disease to diabetes.
Developing cities need to do more to address the needs of pedestrians, according to MIT graduate student Holly Krambeck, who is working on a walkability ranking system for cities.
As such cities grow more congested with cars, changes are often made at the expense of pedestrians, even though walking is the most common means of transportation in developing countries, Krambeck said. She cited the example of New Delhi, India, which recently created a number of new roads without creating new space for walkers.
A dual master's degree candidate in city planning and in science and transportation, Krambeck studied walkability as part of a two-year internship with the World Bank. The work eventually became her master's thesis, which she completed in February.
"How well the pedestrian environment can service (walking) trips will impact the overall quality and efficiency of the urban transportation network, and in turn, overall mobility and accessibility for residents and visitors," Krambeck wrote in her thesis.
Walkability means different things to different people and in different regions, said Krambeck, who had to develop a set of criteria that could be universally applied to cities across the globe. She chose to evaluate "basic walkability," which she defined as "the safety, security, economy and convenience of traveling by foot."
Krambeck developed a test to assess walkability in cities around the globe. Questions included: Is the sidewalk properly lit? Are there benches to relax along the way? Are there accessible public restrooms? Is there ample awning coverage to stay out of the sun and rain? Are the sidewalks clean and well maintained? Are there walking obstructions?
Armed with these questions and others, employees of the World Bank led field tests in Beijing, Hanoi, Bangkok, Manila and Karachi while Krambeck led field tests in Alexandria, Va., and Washington, D.C., followed by a full-scale pilot in Ahmedabad, India, where the World Bank was beginning work on an urban development and upgrade project.
Each city was evaluated based on its history with pedestrian fatalities, design problems, laws regarding sidewalk obstruction, transportation education and planning finances.
In Ahmedabad, for example, there are no urban design guidelines for walking paths. Further, the various laws for pedestrians are rarely enforced because traffic police are not sufficiently funded. Twenty percent of all traffic accidents in the city involve pedestrians, according to the Center for Environmental Planning and Technology.
A team of 65 volunteers took to the streets of Ahmedabad, where they surveyed 12.4 miles of road and polled 350 pedestrians. "It was so important that we get local input," Krambeck said.
Using the criteria, which assessed the condition of walking paths, traffic management at intersections and timing of traffic lights, the volunteers found Ahmedabad to be "a very inhospitable place for pedestrians."
The volunteers reported animal waste in the streets, unpaved surfaces, poor drainage and litter, all of which render the streets unappealing, said Krambeck, who helped create a proposal for the World Bank to upgrade the city's pedestrian accessibility. She said she hopes her findings will be incorporated in the upgrade planning project set to begin this year.
"Ahmedabad planners and officials are unusually receptive to this kind of nonmotorized travel advocacy," said Krambeck, citing a petition signed by 12,000 people requesting bicycle lanes throughout the city. The government began construction on the lanes last year.
As of now, the index ranking the cities is a work in progress. Krambeck presented her work at the annual Association for Pedestrian and Bicycle Professionals conference in Chicago in 2005, and attendees used her methods to assess three different parts of the city.
This past month, she headed to South Africa to present her work on behalf of the World Bank at Velo Mondial -- an annual conference where planners, engineers, advocates and government officials meet to discuss strategies for improving nonmotorized transport infrastructure.
"After the conference, I was able to arrange a meeting with more than 20 local planners to discuss conducting walkability surveys in some of the surrounding townships," Krambeck said. "I also met with a professor at University of Cape Town, Roger Behrens, who had expressed interest in having his students volunteer to conduct some of the walkability field work."
Although she has yet to conduct a test in Boston -- "I would like to," she said -- Krambeck was pleased by her personal experiences walking around town. "I actually think Boston is a very walkable city," she said.