Citizen science research investigates neighborhoods’ effects on well-being

Image courtesy of Ben Chrisinger

When walking through different parts of a neighborhood, how do you feel? Comfortable and relaxed, or stressed and on-alert? And how do these different environments — over days or even years — impact your well-being?

A new Stanford study explores how to answer these kinds of questions using citizen scientists, as recently reported in International Journal of Health Geographics. To learn more, I spoke with lead author Ben Chrisinger, PhD, a postdoctoral research fellow at the Stanford Prevention Research Center.

What inspired you to study the built environment and health?

“I’ve always been fascinated by how and why we perceive different neighborhoods as safe or unsafe, welcoming or unwelcoming, and attractive or unattractive. If we can develop a more granular understanding of where we feel certain ways, and why, it’s possible that we can improve urban design.

Chronic stress contributes to a number of negative health outcomes, ranging from decreased immune function to cardiovascular disease.

Understanding what exactly contributes to stress in different places can be valuable information for individuals. But we also think there’s great potential in pooling these stress data across many individuals to see if common themes exist. Urban planners, policymakers and developers could learn from these themes to better promote health in their communities.”

How did you conduct your recent citizen scientist study?  

“We partnered with an urban design and planning non-profit, Place Lab, in San Francisco. They recruited eight women and six men in their 20s and 30s who lived locally. We had all the volunteers do the same 20-minute walk in a Hayes Valley neighborhood.

We used a citizen-science method called Our Voice, developed by the Healthy Aging Research and Technology Solutions Stanford research group led by Abby King, PhD. Individuals use a smartphone app to take pictures and record audio narratives of their neighborhoods.

We asked people to document things along the walk that they thought were contributing or detracting from their well-being. Their phone app recorded where they took their pictures and audio narratives. Everyone also wore a sensor on their wrist that measured time-stamped biometric data — including blood volume pressure, heart rate, skin temperature and electrodermal activity as a proxy for stress — to show how their bodies responded to different environments.

We then created a web platform to share back the participants’ photos, transcribed audio and biometric data superimposed on a map.”

What did you find?

“The phone app data showed that participants often talked about traffic, noise and whether they felt safe as a pedestrian. Even in high volume areas, people also talked about the aesthetic qualities of streets and historic buildings. It appears that it’s not just parks that are stress reducing — quiet areas might also be important. We need to do more research to understand the elements that provide a break from the urban environment.

Our exploratory statistical analyses revealed that, on average at the group level, there were significant associations between participants’ electrodermal activity and the built-environment characteristics. However, it’s clear that these models explain some participants’ data much better than others. One possible explanation is that we’re leaving out some influential neighborhood variables.”

 What’s next?

“We want to do this again with more people all walking a smaller section — like one alley or a pair of streets — so we can dig deeper into what explains the differences between people’s perceptions of specific places.

We also want more diversity in the age, race and ethnicity of our participants. We know this is important from earlier citizen scientist projects. For example, a previous study showed that kids take pictures of graffiti and see it as a good thing, as art, whereas older adults see it as vandalism.”

This is a reposting of my Scope blog story, courtesy of Stanford School of Medicine.

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New study observes Tuberculosis bacteria attacking antibiotics

Photograph by torange.biz

Tuberculosis was one of the deadliest known diseases, until antibiotics were discovered and used to dramatically reduce its incidence throughout the world. Unfortunately, before the infectious disease could be eradicated, drug-resistant forms emerged as a major public health threat — one quarter of the world’s population is currently infected with TB and 600,000 people develop drug-resistant TB annually.

New research at SLAC National Accelerator Laboratory is seeking to better understand how this antibiotic resistance develops, as recently reported in BMC Biology.

TB is caused by Mycobacterium tuberculosis bacteria, which attack the lungs and then spread to other parts of the body. The bacteria are transmitted to other people through the air, when an infected person speaks, coughs or sneezes.

These bacteria survive antimicrobial drugs by mutating. Their resilience is enhanced by the lengthy and complex nature of standard treatment, which requires patients to take four drugs every day for six to nine months. Patients often don’t complete this full course of TB treatment, causing the bacteria to evolve to survive the antibiotics.

Now, a team of international researchers has investigated an enzyme, called beta-lactamase, that is produced by the Mycobacterium tuberculosis bacteria. They wanted to understand the critical role this enzyme plays in TB drug resistance.

Specifically, the researchers made tiny crystals of beta-lactamase and mixed them with the antibiotic ceftriaxone. A fraction of a second later, they hit the enzyme-antibiotic mixture with ultrafast, intense X-ray pulses from SLAC’s Linac Coherent Light Source — taking millions of X-ray snapshots of the chemical reaction in real time for two seconds.

Putting these snapshots together, the researchers mapped out the 3D structure of the antibiotic as it interacted with the enzyme. They watched the bacterial enzyme bind to the antibiotic and then break open one of its key chemical bonds, making the antibiotic ineffective.

“For structural biologists, this is how we learn exactly how biology functions,” said Mark Hunter, PhD, staff scientist at SLAC and co-author on the study, in a recent news release. “We decipher a molecule’s structure at a certain point in time, and it gives us a better idea of how the molecule works.”

The research team plans to use their method to study additional antibiotics, observing in real time the rapid molecular processes that occur as the bacteria’s enzymes breakdown the drugs. Ultimately, they hope this knowledge can be used to design better antibiotics that can fight off these attacks.

This is a reposting of my Scope blog story, courtesy of Stanford School of Medicine.