Following the people and events that make up the research community at Duke

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Symposium Explores How People and Nature are Inextricably Entwined

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The massive Keeler Oak, a white oak (Quercus alba) in New Jersey.

An April symposium at Grainger Hall, People and Nature, brought a diverse set of speakers, both from Duke and other U.S. institutions, to examine the relationship between human culture and land and to discuss pressing issues such as environmental justice. The session was organized by PhD students Nicholas School of the Environment and the biology department.

Paul Manos of Duke Biology

Professor Paul Manos of Duke Biology told us  how oaks, ubiquitous tree species in temperate regions, can make people think about nature. A walk in the woods looking at the different oaks can result in a fascinating journey of natural history. For those who are curious enough, an inquiry into the lives of oaks will take them deep into topics such as evolutionary history, leaky species boundaries, plant-animal interactions, among others, Manos said. Keeping true to the theme of the symposium, Manos explored some hypotheses about the first time that humans had contact with oaks, and how this relationship unfolded ever since.

Orue Gaoue of Tennessee-Knoxville

Associate Professor Orou G. Gaoue of the University of Tennessee, Knoxville,  took us through a detailed case study of human and plant interactions with long-term data from the country of Benin, in Africa. He showed how the harvest of the African mahogany (Khaya senegalensis) affects human demography and even the marriage dynamics of the Fulani people, with many other insights into the intertwined relationship of the locals and their harvest.

Andrew Curley of Arizona

Central to the morning sessions were the rights of nature and the granting of personhood to non-humans, which is common in the cosmology of many indigenous cultures. For instance, Andrew Curley, assistant professor at the University of Arizona, mentioned in his talk that the O’odham people in the Sonoran Desert confer the Saguaro cactus personhood status. His talk exposed how colonial dynamics have created climate catastrophes and drought around the Colorado River, how indigenous peoples have to navigate these foreign systems, and how they understand their relationship with the land and water.

Michelle Carter, a first-year Masters of Environmental Management (MEM) student at Duke, examined the feasibility of the rights of nature in the US legal system. These rights allow certain natural features (e.g. rivers) to stand as a sole party in litigation and recover damages on their behalf. However, effective application and the enforcement of policy have been lacking.

The second part of the symposium focused on environmental justice. Duke Ph.D. student Maggie Swift presented a land acknowledgement which was divided into three parts: recognition of the violent history of the past; an understanding of the present with a celebration of the lives and achievements of current indigenous peoples; and a call to action so that participants were encouraged to financially support native-led organizations.  Links for donations and more information can be found on the symposium website. The land acknowledgement was followed by a brief presentation on the project Unearthing Duke Forest  that explores the human history surrounding Duke Forest.

Why is it important to jointly consider people and nature in your work? What insights do you gain in your work by taking this approach?

People & NAture
Christine Folch of Duke Cultural Anthropology

Assistant professor Christine Folch, from Duke’s Department of Cultural Anthropology provided an analysis of the discourse around climate change. At the center was the question “do you believe in climate change?” which has ingrained the element of doubt and the ability of the speaker to say “no, I don’t.”  

Associate professor Louie Rivers III, from NC State University,  gave a talk on perceived environmental risks and their influence on social justice. He pointed out that these questions  could be dismissed by certain groups such as black farmers, who are concerned and disproportionally affected by environmental issues but might not relate to how the question is addressed.

Sherri White-Williamson, Environmental Justice Policy director at NC Conservation Network, explained the concept of environmental justice and provided concrete examples of how certain policies (e.g. federal housing/lending policies or interstate highway systems) can create inequalities that leave communities of color to bear the exposure of environmental degradation. She also made us aware that this year is the 40th anniversary of the birth of the US environmental justice movement that started when an African-American community  in Warren County, North Carolina organized to fight a hazardous waste landfill.

No exploration of people and nature would be complete without including the seas. A team of three students at the Duke University Marine Lab, undergrad Maddie Paris, second-year MEM Claire Huang, and Ph.D. student Rebecca Horan, presented two case studies of social and ecological outcomes linked to education and outreach interventions conducted in tropical marine environments.

Their first case study was on turtle education in Grenada, West Indies. Here a 10-week summer program for local children ages 9-12 created an improved understanding of marine turtle biology and its connection to the health of the ocean and their communities. The second case study was a 4-week training course for fisher people and fisheries officers in Mtwara, Tanzania. These participants increased their skills in monitoring the local reefs and were better equipped to educate their communities on marine environmental issues.

The symposium ended with two open questions for the audience, which should be considerations for anyone doing environmental research:  Why is it important to jointly consider people and nature in your work? What insights do you gain in your work by taking this approach?

Guest post by Rubén Darío Palacio, Ph.D. 2022 in Conservation Biology from the Nicholas School of the Environment, and science director of conservation non-profit Fundacion Ecotonos in Colombia.

Deep Conversations Put the ‘Care’ in Healthcare

The Duke Medical Ethics Journal (DMEJ) is a golden opportunity to listen to the ways the world around me hurts and heals. It means asking questions – who is being marginalized in my communities? Where is the injustice in my community? What can I do about it? And when these questions feel too big and too heavy, DMEJ means having a community of mentors, friends, and soul-strengtheners to ask the questions with me. Some of my most cherished experiences at Duke since freshman year have been those rooted in exploring the humanities.

Engaging with the field of ethics through the Kenan Institute of Ethics Living Learning Community as well leading the Duke Medical Ethics Journal (DMEJ) has given me a strong appreciation for the utilization of humanities in healthcare.

Before I saw the Spring 2021 DMEJ edition come together, I never realized how deeply identity could influence health. I had always thought of peoples’ identity in terms of cultural identity, not enough in terms of fertility or neurodiversity, until I read the pieces written by my fellow DMEJ writers. I realized more than ever that healthcare at its deepest level is not just about the biomedical model but it’s also about care, care for the values the lives of its practitioners and patients.

COVID-19 has also naturally brought up questions on the importance of mask-wearing, social distancing, and now, vaccinating. Though most students interested in entering the healthcare field typically fall on one side of the argument, it is safe to say that all of us had to take up more responsibility for ourselves and for others. What does it take to do what is right? The ethics (and effort!) surrounding this responsibility makes for deep conversations puts the “care” in healthcare. And these deep conversations are what DMEJ is all about.

Our upcoming issue, winter 2021, will be about the post-covid era. What does a return to normalcy even mean in an age where normal has been changed forever? And two of our bloggers have already written deeply affecting pieces on post pandemic mental health. To stay up to date on what DMEJ is up to, subscribe to our listserv. We’re always looking for more voices to join our conversation. 🙂

Guest post by Sibani Ram, Class of 2023

Child Protective Services Do Work, But They Are Unevenly Distributed

Roughly one in seven  New York City children suffer confirmed mistreatment at home and many are placed in foster care. But relatively few children are permanently separated from their parents by the termination of parental rights, according to new research from Duke University and Rutgers University-Newark.

The data points to a relative success story in the world of child welfare, said Chris Wildeman, a Duke University sociologist and co-author of the research. In New York City, child welfare specialists intervene often in abuse and neglect cases but are often able to avoid terminating parental rights, even when they do remove the child from the home, Wildeman added.

Wildeman’s co-authors are Kieran Healy, a Duke sociologist, and Frank Edwards and Sara Wakefield from the School of Criminal Justice at Rutgers University – Newark.

In New York City, roughly two in five children will be involved in an investigation by their local child protective services office; one in seven will experience confirmed maltreatment, one in 35 will be placed in foster care. (Dallas Clemons)

“I think the core takeaway there is that New York is the prime example of taking maltreatment seriously and intervening as a system,” Wildeman said. “But also taking seriously the idea that permanent termination of parental rights totally closes off any chance for family reunification, so only doing it in the most extreme circumstances.”

The peer-reviewed study, appearing the week of July 19 in the Proceedings of the National Academy of Sciences, derives from an analysis of child welfare data from the nation’s 20 most populous counties. (The New York data is from all five boroughs because the entire city’s child welfare system is under a single governing umbrella)

The study looked at how often children were the subject of a child services investigation; suffered confirmed mistreatment, were placed in foster care, and removed permanently from their homes through the termination of parental rights.

Nationally, roughly one in three children will be involved in an investigation by their local child protective services office; one in eight will experience maltreatment, one in 17 will be placed in foster care and one in 100 will have parental rights terminated, according to the study.

In New York City, roughly two in five children will be involved in an investigation by their local child protective services office; one in seven will experience confirmed maltreatment, one in 35 will be placed in foster care and one in 600 will have parental rights terminated, according to the study.

Nationally, one in 100 parents will have their rights terminated, while in New York that figure is one in 600. (Dallas Clemons)

“The system is functioning more the way many child welfare advocates would like it to function,” Wildeman said. “Make sure you identify maltreatment, but attempt to use services rather than foster care treatment, at least initially, and then only terminating parental rights in only the most extreme circumstances. And trying to be aware of racial disparities in those processes.”

CITATION:  “Contact with Child Protective Services is Pervasive but Unequally Distributed by Race and Ethnicity in Large US Counties,” PNAS, July 19, 2021. DOI: 10.1073/pnas.2106272118

Post by Eric Ferreri , Duke University Communications

A New Algorithm for “In-Betweening” images applied to Covid, Aging and Continental Drift

Collaborating with a colleague in Shanghai, we recently published an article that explains the mathematical concept of ‘in-betweening,’in images – calculating intermediate stages of changes in appearance from one image to the next.

Our equilibrium-driven deformation algorithm (EDDA) was used to demonstrate three difficult tasks of ‘in-betweening’ images: Facial aging, coronavirus spread in the lungs, and continental drift.

Part I. Understanding Pneumonia Invasion and Retreat in COVID-19

The pandemic has influenced the entire world and taken away nearly 3 million lives to date. If a person were unlucky enough to contract the virus and COVID-19, one way to diagnose them is to carry out CT scans of their lungs to visualize the damage caused by pneumonia.

However, it is impossible to monitor the patient all the time using CT scans. Thus, the invading process is usually invisible for doctors and researchers.

To solve this difficulty, we developed a mathematical algorithm which relies on only two CT scans to simulate the pneumonia invasion process caused by COVID-19.

We compared a series of CT scans of a Chinese patient taken at different times. This patient had severe pneumonia caused by COVID-19 but recovered after a successful treatment. Our simulation clearly revealed the pneumonia invasion process in the patient’s lungs and the fading away process after the treatment.

Our simulation results also identify several significant areas in which the patient’s lungs are more vulnerable to the virus and other areas in which the lungs have better response to the treatment. Those areas were perfectly consistent with the medical analysis based on this patient’s actual, real-time CT scan images. The consistency of our results indicates the value of the method.

The COVID-19 pneumonia invading (upper panel) and fading away (lower panel) process from the data-driven simulations. Red circles indicate four significant areas in which the patient’s lungs were more vulnerable to the pneumonia and blue circles indicate two significant areas in which the patient’s lungs had better response to the treatment. (Image credit: Gao et al., 2021)
We also applied this algorithm to simulate human facial changes over time, in which the aging processes for different parts of a woman’s face were automatically created by the algorithm with high resolution. (Image credit: Gao et al., 2021. Video)

Part II. Solving the Puzzle of Continental Drift

It has always been mysterious how the continents we know evolved and formed from the ancient single supercontinent, Pangaea. But then German polar researcher Alfred Wegener proposed the continental drift hypothesis in the early 20th century. Although many geologists argued about his hypothesis initially, more sound evidence such as continental structures, fossils and the magnetic polarity of rocks has supported Wegener’s proposition.

Our data-driven algorithm has been applied to simulate the possible evolution process of continents from Pangaea period.

The underlying forces driving continental drift were determined by the equilibrium status of the continents on the current planet. In order to describe the edges that divide the land to create oceans, we proposed a delicate thresholding scheme.

The formation and deformation for different continents is clearly revealed in our simulation. For example, the ‘drift’ of the Antarctic continent from Africa can be seen happening. This exciting simulation presents a quick and obvious way for geologists to establish more possible lines of inquiry about how continents can drift from one status to another, just based on the initial and equilibrium continental status. Combined with other technological advances, this data-driven method may provide a path to solve Wegener’s puzzle of continental drift.

The theory of continental drift reconciled similar fossil plants and animals now found on widely separated continents. The southern part after Pangaea breaks (Gondwana) is shown here evidence of Wegener’s theory. (Image credit: United States Geological Survey)
The continental drift process of the data-driven simulations. Black arrow indicates the formation of the Antarctic. (Image credit: Gao et al., 2021)

The study was supported by the Department of Mathematics and Physics, Duke University.

CITATION: “Inbetweening auto-animation via Fokker-Planck dynamics and thresholding,” Yuan Gao, Guangzhen Jin & Jian-Guo Liu. Inverse Problems and Imaging, February, 2021, DOI: 10.3934/ipi.2021016. Online: http://www.aimsciences.org/article/doi/10.3934/ipi.2021016

Yuan Gao

Yuan Gao is the William W. Elliot Assistant Research Professor in the department of mathematics, Trinity College of Arts & Sciences.

Jian-Guo Liu is a Professor in the departments of mathematics and physics, Trinity College of Arts & Sciences.

Jian-Guo Liu

Pardon the Irruption: Winged Northern Visitors Massed for Tasty NC Mast

One morning in November, during a visit to my parents’ house in Richmond, Virginia, I woke up to a text from my mom. “Evening Grosbeaks at the river. Want to go?” Obviously I wanted to go. I’d heard that they had left their normal range, but I was shocked that they’d made it to Richmond—Evening Grosbeaks hadn’t come this far south in decades.

Evening Grosbeaks on a feeder in Hillsborough. The males are bright (lower right), the females more understated (upper left and right). A Purple Finch (center), another northern visitor, has joined them. (Lane Scher)

This winter has been a special treat for birdwatchers—a huge “irruption” year for many northern bird species, like the Evening Grosbeak. Many irruptive species are in the finch family, which includes siskins, redpolls, crossbills and some grosbeaks. These species usually spend their winters in the northern US and Canada, but every so often they’ll journey farther south. What causes these birds to make massive flights some years and not others? It’s simple—food.

Many birds eat seeds from trees, which scientists call “mast,” in winter. But mast is produced irregularly in cycles—lots of mast one year, and little the next. Birds with irruptive migratory patterns move around to find food in winter. During years of large mast production, irruptive birds can stay in their preferred range farther north. But when food is scarce, they fly south.

Mast is an important food source not only for these irruptive bird species, but also for local bird species and mammals. In fact, mast cycles impact the entire forest food web. Years of high seed production, sometimes called “bumper crops”, lead to larger rodent populations, which then eat the eggs of songbirds. Mast might also be tied to outbreaks of tick-borne diseases like Lyme disease: rodent populations grow in big mast years, which means there are more hosts for ticks, leading to more disease.

Mast cycles can have such massive impacts on animal populations because the seed production of each tree species is synchronized across large geographic areas. That means that in one year, trees of a particular species in one area will produce many seeds, but in a neighboring region the same species might produce few seeds. These patterns create a food landscape that is dynamic across both space and time.

Ecologists want to understand how mast cycles work—and Duke is home to the founder and headquarters of MASTIF, a global network with exactly this goal. Dr. Jim Clark of the Nicholas School of the Environment wants to understand how climate drives mast cycles, and how these cycles will change under climate change. The MASTIF network is a huge collaboration that now includes over 2.5 million data points, each representing the mast produced by one tree in one year.

The Evening Grosbeak map from
Peterson’s Field Guide to Eastern Birds shows that food-seeking irruptions can indeed reach Florida, as they have this year.

As a PhD student in Dr. Clark’s lab, I’m studying the relationship between mast cycles and the bird populations they support. I want to understand how birds respond to an environment that is constantly changing—in this case, how they respond to spatial and temporal changes in food availability. This historic irruption year is a perfect example of exactly this question: a year of low mast in the north has caused bird species to travel far outside their normal range to find food.

Interestingly, the association between these irruptive birds and food availability is so strong that it can be predicted fairly easily. The Winter Finch Forecast is based on a survey of mast crops across northern North America, which is then translated into a prediction of irruption patterns. The 2020 forecast noted that Evening Grosbeak populations would be larger this year due to outbreaks of spruce budworm, an important food source during the breeding season. This increase in the population size, combined with low winter food abundance, has led to a historic flight south.

The Clark Lab’s goal of understanding and predicting mast cycles would further our knowledge of these bird species’ unique migration patterns. With a more thorough understanding of mast patterns, we could better anticipate irruptions and implement informed conservation strategies. In addition to monitoring trees in long-term forest plots, the team uses data collected by citizen scientists through the MASTIF project on iNaturalist. With over 7,000 observations from 81 people across the world, these citizen scientists have contributed a huge amount of data.

I was thrilled to see the Evening Grosbeaks in November, and I assumed it would be my only chance. But since then, they’ve been seen throughout the Carolinas and into northern Florida. Recently, a homeowner in Hillsborough spotted a group of Evening Grosbeaks in his yard. He reported them to eBird, a citizen science project that collects data from birders around the world, and that birders use to locate rare species.

Since he reported them, birders have flocked to his yard in numbers almost as stunning as the birds themselves. Over the last few weeks, he’s counted up to 60 grosbeaks on a good day, and his yard has been visited by over 250 birders. Birders don’t want to miss this—no one knows when the next big irruption will be.

Guest post by Lane Scher, a Ph.D. student in Ecology at the Nicholas School of the Environment.

Physician-Scientist Takes the Long View and Sets Her Sights High

Dr. Bryan Batch, a Duke endocrinologist and researcher, studies treating metabolic disorders (like diabetes) with non-pharmacological approaches. But, she says, her parents’ medical professions, and the hard work that went into them, resulted in her not wanting to pursue science at all as a child.

Bryan Batch MD

When she took biology in middle school however, it clicked. It didn’t feel like “the slog of math,” she says, because she enjoyed studying life in its different forms. This infatuation with science combined with a love for other people pushed her to pursue medicine.

Now, Dr. Batch focuses on racial disparities. She says that a huge issue with disparities, whether they involve race, poverty, food insecurity, educational opportunity, or health insurance, is that they are often driven by policy. “We are not trained to know how to affect change in policy in medical school — it’s not something we are taught. But I do think if physicians got more involved in politics and policy we would be able to make significant positive impact.”

What she does try to do is adapt to individual patient needs in the moment. Her work at Duke signifies what she, as a healthcare provider, can do within the time spent with patients to interact in the best way possible. For example, she can understand if someone has a literacy issue and adapt her methods of explanation so that their literacy doesn’t hinder their understanding. While it can be challenging for one person to change systemic issues or share lived experiences with people of different backgrounds, Dr. Batch makes every effort to create a comfortable environment where she is able to leave a positive impact.

These impacts have no doubt been affected by COVID-19, which Dr. Batch describes as one of the most challenging experiences in her twenty years of practicing medicine. Although telephone and video conferencing have been available for years, Dr. Batch explains that only now is there a drive to put them to use. “It was like someone came up behind you and just whacked you on the head,” she says — no warning, no time to get organized.

Dr. Batch feels lucky to be in endocrinology, where there is flexibility for remote visits. Yet, even when patients do have the chance to have an in-person visit, some don’t want to. If they do, the physical separation, masks, and face shields create a feeling of distance. Dr. Batch spends much of her clinical time at the Durham Veteran Affairs Hospital, across the street from Duke Hospital, where many hearing-impaired patients have difficulty understanding her words because her mask takes away the ability to read lips.

Dr. Batch says that even after the pandemic has passed, more than 30% of visits may remain over the telephone, which can give patients increased access to their doctors.

The challenges have infiltrated her research too, where now the only people she can bring in are those who need to visit the VA Medical Center for another reason anyway, like going to the eye doctor. Overall, she says, she has been surrounded by phenomenal people who rolled up their sleeves and said “let’s get it done.” Still, it has been exhausting.

The Durham Veterans Administration Medical Center, where Dr. Batch conducts most of her practice.

To her, family is everything, and she tries her best to stay in touch with the people who matter most as a way to get through it all.

Even before COVID-19, Dr. Batch has been intentional about living her life to the fullest and staying true to her core values. If that means rescheduling things at work to be with her kids, she is unapologetic. She chose endocrinology as a specialty in part because it’s very family-oriented, and she feels lucky to have colleagues who understand the flexibility she values. Her ultimate goal is to leave a mark on the world but she also wants her happiness to come from what matters, so she stays close to her big family and lots of friends.

While sacrifices are inevitable in any career, Dr. Batch tries not to make large ones on the homefront. She takes it day by day, week by week, she says, to make it such that “work” and “life” are in harmony as much as possible. It is easy to get caught up and have the years go by, one day realizing that the important people have pulled away.  Dr. Batch is deliberate about making the time for these people, including her two children and husband.

Dr. Batch is a role model for young people, particularly for women of color. She shared an anecdote about her inattentive high school counselor, to whom she went for a signature on her college application list. Seeing Yale, Harvard, and Brown, he told her that she was “reaching too high.” Batch responded, “I’m not here for your opinion on this list. I’m here for you to sign this form..

She ended up at Yale.

She says she had the courage to talk back to the counselor  because her parents instilled the idea of working hard and pushing higher. What matters, she says, is believing in yourself and surrounding yourself with people who believe in you.

 Unfortunately, Batch said, underestimation by others resonated throughout her college, medical school, residency, and fellowship, because she is a woman or because she is Black.

At the end of the day, Dr. Bryan Batch never let other people define her experience but instead allowed her hard work to prove her value and propel her to always reach higher.

Guest Post by Viha Patel, Class of 2021, NC School of Science and Math

Cybersecurity for Autonomous Systems

Over the past decades, we have adopted computers into virtually every aspect of our lives, but in doing so, we’ve made ourselves vulnerable to malicious interference or hacking. I had the opportunity to talk about this with Miroslav Pajic, the Dickinson Family associate professor in Duke’s electrical and computer engineering department. He has worked on cybersecurity in self-driving cars, medical devices, and even US Air Force hardware.

Miroslav Pajic is an electrical engineer

Pajic primarily works in “assured autonomy,” computers that do most things by themselves with “high-level autonomy and low human control and oversight.” “You want to build systems with strong performance and safety guarantees every time, in all conditions,” Pajic said. Assured Autonomy ensures security in “contested environments” where malicious interference can be expected. The stakes of this work are incredibly high. The danger of attacks on military equipment goes without saying, but cybersecurity on a civilian level can be just as dangerous. “Imagine,” he told me, “that you have a smart city coordinating traffic and that… all of (the traffic controls), at the same time, start doing weird things. There can be a significant impact if all cars stop, but imagine if all of them start speeding up.”

Pajic and some of his students with an autonomous car.

Since Pajic works with Ph.D. students and postdocs, I wanted to ask him how COVID-19 has affected his work. As if on cue, his wifi cut out, and he dropped from our zoom call. “This is a perfect example of how fun it is to work remotely,” he said when he returned. “Imagine that you’re debugging a fleet of drones… and that happens.” 

In all seriousness, though, there are simulators created for working on cybersecurity and assured autonomy. CARLA, for one, is an open-source simulator of self-driving vehicles made by Intel. Even outside of a pandemic, these simulators are used extensively in the field. They’ve become very useful in returning accurate and cheap results without any actual risk, before graduating to real tests.

“If you’re going to fail,” Pajic says, “you want to fail quickly.”

Guest Post by Riley Richardson, Class of 2021, NC School of Science and Math

Her Research Path Winds Through a Plant’s Growth

The beauty of research is that it allows you to take control of your own path.

“We are very lucky to be in the position to decide what we love to do and do it,” says Tai-ping Sun, a Duke biology professor studying the plant hormone GA. Researchers get to take control of their own path, she said. Every day is an opportunity to learn something new, design and analyze experiments and decide what direction to take.

Tai-ping Sun is a professor of Biology at Duke

Sun studies the GA signaling pathway because it regulates plant growth and development. She got interested in GA when she was a post-doctoral fellow at Harvard University in 1988. At the time, a lot of tools needed to be developed. As she was developing new tools to clone plant genes, she came across a GA mutant that was different. Her research is very important to understanding how the mutations in the GA signaling pathways can control the height of a plant. In fact, she says, GA mutations were one of the reasons for the success of the “Green Revolution” in the 1960s.

Sun’s current research revolves around identifying the mechanisms of the cell that make GA hormones and identifying how GA mutations have affected this pathway. Her team has identified important facets of the pathway, such as the structure and function of the nuclear receptors that allow for transcription that drives the GA response. Her team has also identified transcription factors that control the rate of the signaling pathway such as the DELLA proteins that act as master growth repressors to inhibit GA response. In fact one of her favorite discoveries is that GA triggers destruction of the DELLA proteins to activate the GA signaling pathway.

A figure from a 2004 paper by Sun on plant growth.
All three of the mutants grew less well than wild type plants.

“As a scientist, the most exciting thing is to discuss experimental data, and then trying to deduce hypothesis or modify models and then come up with new experiments for testing,” she said.

But research is not without its challenges, Sun says “not everything that you do works out the first time.” That’s why she says that as a researcher the most important thing is to have an interest in your field as well as perseverance.

Guest post by Anika Jain, Class of 2021, NC School of Science and Math

A Computer Scientist Investigating the Source Code of Life

We are all born with defining physical characteristics. Whether it be piercing blue eyes or jet black hair, these traits distinguish us throughout our entire lives. However, there is something that all of our attributes have in common, a shared origin: genes.

Beyond dictating our individual features, genes instruct cells to create proteins that are essential for a variety of processes, from controlling muscle function to managing digestive systems. Despite their importance in the workings of our body, genes can also code for detrimental diseases, such as Huntington’s disease or Duchenne muscular dystrophy.

Raluca Gordân, Ph.D.

These types of diseases are exactly what Raluca Gordân, Ph.D. is battling through her research. She and her group are trying to figure out how to decode the non-coding genome, the DNA apart from protein-coding genes. They are deepening their understanding of the role non-coding areas of the genome play in the expression of the coding genes and the production of proteins.

Gordân, an associate professor in biostatistics and bioinformatics at Duke, said a majority of disease-causing genetic mutations derive from the genome outside of genes.

“That is a huge search space,” she says, chuckling. “Genes only make up about 2% of the genome. If we don’t understand what those non-coding regions are doing, it’s hard to make predictions about what the mutation in those regions would be doing and how to connect that to the development of a disease.”

Gordân recently published a paper, entitled “DNA mismatches reveal conformational penalties in protein–DNA recognition,” which focuses on transcription factors and their exceptional ability to bind to mispaired DNA, misspellings that occur as DNA is copied. During regular replication, nucleotide bases (the building blocks of our DNA) are paired correctly, where adenine pairs with thymine and cytosine goes with guanine. However, when an error occurs during replication, mispairs start to appear, as adenine may pair with guanine instead.

“Normally, those are mistakes that get repaired by specific mismatch repair pathways but that repair might not happen if one of these transcription factors sits on the replication error and doesn’t allow the repair mechanism to see it,” Gordân explains. “Normally, one would expect the transcription factors not to bind to those errors. But we found that they can bind way better than their actual genomic targets.”

Modeling of the binding between mismatched DNA and transcription factors.

To expand on her computational discovery, Gordân is now following up with a study of transcription factor binding to mismatches in living cells, observing whether they adopt their usual role of regulating gene expression or contribute to the development of mutations.

Gordân’s research is a product of her passion and desire to make change. It also can be attributed to a series of realizations she made during college and inspirational mentors who guided her along the way.

While pursuing her undergraduate degree, Gordân was a purely computer science major, concentrating on cryptography. However, as she was nearing the end of her four years of college, she soon found herself yearning for the opportunity to do more. She began looking into machine learning applications and enrolled in a course based around genetic algorithms which she credits for launching her career path.

At that point, she attained what she describes as her “first taste of genetics” and her interest in bioinformatics was irrevocably piqued. Thereafter, Gordân applied for a PhD at Duke, where she worked with advisor Alex Hartemink investigating transcription factor proteins in regulatory genomics. At Duke, her work was primarily computational.  But with her postdoctoral advisor Martha Bulyk of Harvard Medical School, Gordan was exposed to the more experimental aspects of biology.

Today, she recognizes these experiences as integral to her ongoing research, which requires her to frequently iterate between observational approaches and computational work.

Gordân is acclimating to the newly quarantined world. While she strives to continue her research, in the pandemic, it has changed her routine.

“I think what was affected a lot since the pandemic started is the fact that we don’t meet in person,” she says. “A lot of the quick progress was being made when we were in the same physical space and were able to get feedback immediately, with students learning about each other’s results in the lab, in real time. That was replaced with Zoom meetings, where students get to see the other students’ results mainly at lab meetings, weeks or months later. Those continuous discussions that were going on in the lab all the time. We’re missing that.”

Gordân offered some thoughtful parting advice to aspiring computational biologists, like me.

“I was trained as a computer scientist, so I wasn’t really sure about experimental work. But after actually doing the experimental work, I realized how much value there is in doing both,” she said. “You have to pick what you’re strongest at, either the computational or experimental part, but you should not be afraid of the other side.”

Guest Post by Akshra Paimagam, Class of 2021, NC School of Science and Math

Why Ruffed Lemurs (and Their Gut Microbes) Need to Eat Greens

We offered fruit-eating ruffed lemurs at the Duke Lemur Center fresh lettuce each afternoon for 10 days. They happily ate it and their gut microbiomes shifted, suggesting that leafy greens could be incorporated into the lemurs’ standard dietary regimen to boost foraging opportunity and fiber intake.

Red-ruffed lemurs and black-and-white ruffed lemurs are some of Madagascar’s most iconic wildlife. Sporting a long snout and a neck ruff to rival those of the Elizabethan court, these primates naturally live in the rainforests, where they mostly eat fruits and flowers, and make their living as seed dispersers and pollinators.

Ruffed lemurs really like romaine lettuce and their gut bugs do too! (Lydia Greene)

Ruffed lemurs also live in zoos worldwide, where they are given fruit-rich diets to match those foraged by their wild peers. But scientists are starting to realize that the fruit eaten by wild lemurs is quite different from the domesticated fruit provided at zoos. Wild fruits are seedy, pulpy, and thick-skinned, whereas orchard fruits are fleshy, plump, and sweet. From a nutritional standpoint, wild fruits contain more fiber, whereas orchard fruits contain more sugar. 

Our team wondered if a fiber boost might benefit Duke’s ruffed lemur colony. But would these fruit-loving lemurs eat their veggies?  

Cue the salad bar.

To test this idea, we offered ruffed lemurs at the Duke Lemur Center a lot of lettuce. Lettuce seemed like a pretty palatable way to stimulate foraging behavior, while boosting fiber intake.

With help from the research department, we offered 19 ruffed lemurs 150-200 grams of romaine lettuce each day, which is about double the weight of their standard diet. We repeated this regimen every day for 10 days, while recording the lemurs’ feeding behavior and collecting fecal samples for gut microbiome analysis. Because gut microbes are chiefly responsible for converting plant fiber into energy for the lemurs, measuring changes to the lemurs’ microbiomes offered a way to ‘see’ the impact of lettuce consumption.

It turns out that ruffed lemurs really like lettuce. They consistently ate lettuce every day and showed no decline in consumption across the study. Younger animals ate more lettuce than did geriatric lemurs, but all lemurs spent more time crunching on lettuce stalks than the leaves.

And their gut microbiomes responded. We noted two microbes that were more abundant on the lettuce diet: a known fiber digester from the Ruminococcaceae family, and a microbe known for its positive association with host health in other animals called Akkermansia.

Despite their classification as fruit eaters, ruffed lemurs readily eat lettuce. We think lettuce can be used to extend the lemurs’ foraging time while boosting dietary fiber. And it might just help replicate the lifestyles experienced by wild ruffed lemurs in their native Malagasy rainforests.     At the Duke Lemur Center, lettuce is now a routine item offered to ruffed lemurs (and other species too!). Next time you come out for a tour (once it’s safe to do so), you might get to see them crunching away on their new favorite snack!

( Read our paper here: https://onlinelibrary.wiley.com/doi/abs/10.1002/zoo.21555 )

Guest Post by Lydia Greene Ph.D., an NSF-sponsored postdoctoral fellow in biology working at the Duke Lemur Center.

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