Each year, The Graduate School honors UNC graduate students in programs across disciplines for their powerful discoveries that contribute to a better future for the people of North Carolina.

We're pleased to present 12 Impact Awards for 2024 and share the honorees' descriptions of their research projects.

Eric Brown


Identifying placental mechanisms linking environmental chemical mixtures to preterm birth disparities

Eric Brown, doctoral candidate in environmental sciences and engineering

“Prenatal exposure to various environmental chemicals, including lead in drinking water, is associated with increased risk of preterm birth. With a rapidly changing climate, the toxicity and distribution of environmental chemicals are projected to increase. To make matters more complicated, research is increasingly demonstrating that pregnant women are exposed to multiple chemical and non-chemical stressors, simultaneously.

Using North Carolina birth certificates between 2003 and 2015, my research seeks to examine how climate change-related factors (PM2.5, ozone, and extreme heat) will increase the toxicity of lead on preterm birth.

My study showed two major findings: (1) 1st trimester exposure to PM2.5 drives the toxicity of the mixture, (2) extreme heat increases the toxicity of environmental chemicals, and (3) neighborhood socioeconomic status (SES) characteristics are associated with exposure to the environmental chemicals. Notably, climate change-related factors and extreme heat above 70°F jointly increases the odds of preterm birth by 577%. Areas with less integration may be more likely to be affected by climate change-related stressors, highlighting the need to identify environmental chemical reduction technologies for disease prevention. These results inform an ongoing biomonitoring campaign with partner physicians at UNC-Chapel Hill to build in chemical testing at routine pregnancy visits.”

Clara Busse


Acute care use in the postpartum period: patterns and maternal perspectives

Clara Busse, doctoral candidate in maternal and child health

“In North Carolina, more than half of pregnancy-related deaths occur after birth, and Black mothers are nearly twice as likely to die from pregnancy-related causes compared to White mothers.

Once they leave the hospital after having their baby, many mothers do not see a healthcare provider until their postpartum check-up about six weeks later. This system, along with the fact that postpartum health concerns are often urgent, may lead mothers to seek care in an emergency department for their postpartum health concerns. Through my dissertation research, I am seeking to understand how often and for which reasons mothers and other people who give birth in North Carolina use emergency healthcare after giving birth.

For this project, I interviewed mothers who used emergency healthcare and analyzed electronic medical records from the University of North Carolina Health System to study postpartum emergency healthcare use. Findings from my dissertation research and related research projects at the University of North Carolina are being used to improve the care that North Carolina mothers receive throughout the University of North Carolina Health System, where one in eight births occur in the state of North Carolina, approximately 17,000 births per year.”

Mark Ciesielski


Characterizing drivers of oyster mortality using quantitative molecular analysis of environmental pathogens in diverse complex matrices

Mark Ciesielski, doctoral candidate in earth, marine and environmental sciences

“Over the past few years, mass mortality events have been plaguing the oyster aquaculture industry throughout the state of North Carolina. These disastrous events have major economic consequences for oyster lease-owners and directly impact the communities that have relied on oyster farming for generations. With major losses of product and profit threatening the longevity of this industry, stakeholders have been looking to develop interventions that would reduce the impact of these increasingly regular occurrences.

My research has focused on identifying the causative agents that lead to the onset of these mortality events. Preliminary analysis of oyster tissue indicated that bacterial infections have been severely compromising oyster function and performance. High-resolution monitoring across eight oyster leases was conducted to track mortality covering diverse geographical regions. Using novel molecular assays, we were able to quantify unique DNA signatures of uncharacterized bacterial pathogens in the water and in oyster tissue. Increases in the concentration of these bacteria directly coincide with the progression of tissue necrosis before and during the observed mortality across all sites.

These results have uncovered key players in the onset of disease that led to wide-scale oyster mortality events. Dissemination of this information can provide valuable insights that would allow for the implementation of targeted mitigation strategies with the goal of preserving the long-standing traditions of oyster farming across the East Coast.”

Mekhala Dissanayake


Race and racial composition of county: investigating maternal health inequities and healthcare systems factors in the rural south

Mekhala Dissanayake, doctoral candidate in epidemiology

“There are stark disparities related to both race and rurality in maternal health outcomes in North Carolina. Availability of maternal healthcare is likely a major contributor—from 2014-2019, six hospitals and nine obstetric units closed in rural North Carolina. Rural North Carolina is racially diverse and geographically stratified by race: counties in Appalachia and the Outer Banks are up to 95% White, while counties in Central/Eastern NC have high concentrations of Black, Hispanic, and American Indian populations. It is important to consider the geographic contexts in which rural people live because of the differential availability of maternal healthcare and subsequent effects on maternal health outcomes.

My dissertation addresses this by contrasting counties within Appalachia/Outer Banks to Central/Eastern North Carolina and determining distributions of maternal healthcare resources (hospitals, obstetric units, and maternal health providers) and outcomes at delivery and the postpartum period. My first aim is to investigate changes in maternal outcomes after hospital and obstetric unit closures in these different county contexts. The second aim determines the effect of equalizing distributions of maternal health resources across rural counties on disparities in maternal outcomes.

My work aims to identify the salient healthcare factors that contribute to racial disparities in maternal outcomes among those living in rural North Carolina. I hope to provide critical public health information on which populations have the highest burdens, where they are concentrated, and potential interventions.”

Clara Eichler


Characterization of the distribution and fate of neutral PFAS in indoor environments including the role of clothing

Clara Eichler, doctoral candidate in environmental sciences and engineering

“North Carolina is among the states with the highest population exposure to per- and polyfluoroalkyl substances (PFAS) in the US. The contamination of the Cape Fear watershed with these "Forever Chemicals" has frequently made headlines in recent years. And rightfully so, because the health effects of PFAS include liver disease, neurodevelopmental problems, and cancer; although for many PFAS, toxicological data are sparse.

Because PFAS make products stain- and water-repellant, they are used frequently in products like cookware, raingear, and upholstery. Therefore, even if all PFAS were successfully removed from water sources, PFAS can linger in homes, where many people spend a lot of time. Unfortunately, we do not know much about the magnitude of indoor exposure to PFAS or about the ability of different indoor reservoirs to accumulate PFAS.

The Indoor PFAS Assessment (IPA) Campaign gave me the opportunity to measure PFAS in indoor air, cloth, dust, and other reservoirs in 11 NC homes. I found significant amounts of PFAS in all indoor reservoirs in all homes, and my research characterizes how PFAS are distributed indoors. For example, I was able to show that cloth is a major reservoir for PFAS, even if the cloth was initially PFAS free. My research highlights the importance of addressing all potential pathways of exposure to PFAS, including indoor exposure. Further, this knowledge can help to develop strategies for PFAS exposure mitigation in homes.”

Xijing Li


Examining the environmental inequity impact of urban heat mitigation on redlining legacy: case study of Charlotte's retrofitting, 2001 to 2020

Xijing Li, doctoral candidate in city and regional planning

“In Charlotte, North Carolina, the urban heat island effect—where urban areas are significantly warmer than rural ones—poses a major challenge. This issue, exacerbated by global warming and historical urban planning decisions like redlining, disproportionately impacts vulnerable communities, highlighting environmental and social justice concerns.

My two-decade-long research in Charlotte maps the progression and uneven impact of urban heat. Despite overall improvements in the city's heat exposure conditions, the most vulnerable populations have not seen commensurate benefits. This indicates a gap in achieving environmental equity, with serious health implications for these groups, including heatstroke and chronic condition exacerbation.

My study's aim is to inform and work with local authorities, urban planners, and community groups to develop inclusive policies. These policies would not only address urban heat mitigation but also tackle the deep-rooted social inequities contributing to this disparity. By focusing on Charlotte, the research sets a precedent for statewide discussions and policy implementations in North Carolina, emphasizing sustainable urban development that equally prioritizes social justice.

My study identifies that solutions to the urban heat island issue are equitable, benefiting all residents, especially those at greater risk. The research underscores the importance of blending environmental strategies with societal equity to effectively combat urban heat challenges.”

Nicole Ochandarena


Contribution of opioid-responsive cortical neurons to development of more precise pain therapeutics

Nicole Ochandarena, doctoral candidate in neuroscience

“Although opioids are powerful pain relievers, they are also addictive and caused over 36,000 overdose deaths each year in North Carolina from 2000-2022—with over 11 North Carolinians losing their lives each day from a drug overdose last year. Thirteen out of every 100 North Carolinians have an opioid prescription, making this an issue with a broad reach in our state. North Carolina needs better pain medicines—so how should we parse apart the addictive and pain-relieving effects of opioids to develop more targeted treatments?

While opioids have been used for centuries, scientists still do not understand their mechanism. Revealing which cells they signal through in the brain will allow for the development of non-opioid strategies to produce only pain relief without side effects, including depressed breathing and addiction.

Using mice as model organisms, my project has already produced a comprehensive description of the cells acted on by opioids across all areas of the cerebral cortex. With this knowledge, I am testing the contributions of these neuron types to addiction and pain relief, with a specific focus on cell types conserved in humans. My work will reveal how acute and chronic opioid use changes cortical activity, generating critical insights into the mechanism of these medications. Through multi-institutional collaborative efforts, our group is harnessing these findings to develop improved therapeutics for pain.”

Ximena Perez-Velazco


Combatting food insecurity among college students at UNC: testing a social marketing intervention to promote SNAP use

Ximena Perez-Velazco, doctoral candidate in nutrition

“Food insecurity (FI)—defined as a lack of consistent access to enough quality, variety, and culturally appropriate foods—is recognized as a major public health crisis in the United States.

Food insecurity affects a wide range of social, socio-economic, and age sub-groups; including college students. College students experience food insecurity at a disproportionately higher rate than the general public. This has significant public health implications, because this experience gives rise to unique consequences for college students related to poor academic performance and college graduation rates, notable determinants of health.

The Supplemental Nutrition Assistance Program (SNAP) is the largest US federal-level nutrition assistance program that provides food purchasing benefits to eligible low-income individuals and families. It is well understood that SNAP is an effective method to combat food insecurity and improve diet quality. Even though many may be eligible, students enrolled in institutions of higher education rarely apply for or receive SNAP benefits.

The purpose of my study is to inform, develop, and test an intervention designed to address the misunderstandings and lack of awareness surrounding SNAP benefits, to evaluate how to best increase applications to SNAP, and self-efficacy around SNAP, among college students at UNC-CH. If evidence is provided on the effectiveness of the intervention, we will provide recommendations for how it can be disseminated to other institutions of higher learning to address food insecurity on a larger scale.”

Allie Reimold


A mixed methods approach to studying dollar stores as food retailers

Allie Reimold, doctoral candidate in health behavior

“Dollar stores like Dollar General and Dollar Tree are the fastest growing food retailers in the United States (U.S.). This growing retail sector may negatively impact nutrition and associated health outcomes, especially for low-income communities who disproportionately shop at them. As a result, more than 25 U.S. municipalities have passed policies to limit dollar store growth.

New Hanover County, in the Cape Fear Region of North Carolina, has more dollar stores by land area than any other county in the state. To ensure an equitable food environment, local organizations and policy makers need to better understand this emerging issue. In collaboration with the local non-profit, Feast Down East, my research aims to: 1) understand how and why individuals with low incomes rely on dollar stores for food; and 2) highlight their voices in local discussions about policy and programmatic options.

I found that study participants rely on dollar stores because the affordable prices and convenient locations address their persistent barriers to accessing food at traditional retailers. Though they appreciate dollar stores, participants frequently discussed wanting fresh fruit and vegetable options and higher quality proteins in the stores. Participants support policies and programs like SNAP dollar-for-dollar matching for fruits and vegetables, increasing the variety of fruits and vegetables available, and promoting healthy options at dollar stores. These findings have informed Feast Down East efforts and were presented during a participatory "Data Party" with the Cape Fear Food Council for collaborative identification of responsive next steps for decision makers in the Cape Fear Region.”

Molly Remch


Evaluation of two novel restrictive housing diversion units in North Carolina prisons

Molly Remch, doctoral candidate in epidemiology

“Mass incarceration is a clear and pressing public health and health equity issue in North Carolina, with an incarceration rate that far surpasses that of most democratic countries in the world. Incarceration and restrictive housing (i.e., solitary confinement) are each disproportionately applied to Black North Carolinians and North Carolinians with mental health disorders.

Through ongoing collaborative partnerships with the North Carolina Department of Adult Corrections and Division of Public Health, I led evaluations of two novel North Carolina prison restrictive housing diversion units, Therapeutic Diversion Units (TDUs) and the Rehabilitative Diversion Unit (RDU).

We found that individuals in TDU had lower rates of inpatient mental health admissions and self-injury than those placed in restrictive housing; these benefits were not sustained when individuals returned to the general prison population. Similar rates of infractions among those in TDU and restrictive housing indicate TDU does not pose a security risk. We concluded that TDU is a viable, health-promoting alternative to restrictive housing, but additional step-down programming and continued access to therapeutic services in the general prison population would be beneficial. In our evaluation of RDU, we found that rates of violent infractions, mental health needs, and self-injury were lower in RDU than in restrictive housing. However, violent infractions resumed more quickly post-RDU than post-restrictive housing. We concluded that RDU was an important tool for improving mental and behavioral health, but this population would benefit from sustained step-down programming.”

Shuang Xu


Multisource Cone Beam Computed Tomography using a Carbon Nanotube X-ray Source Array

Shuang Xu, doctoral candidate in materials science

“In the landscape of computed tomography (CT) imaging, the choice has often been between high-quality but bulky multidetector CT (MDCT) and the portable, cost-effective cone beam CT (CBCT) that sacrifices image accuracy. Our breakthrough multisource CBCT (ms-CBCT) harmonizes their advantages, delivering MDCT's image quality with CBCT's practical advantages.

The innovation at the heart of ms-CBCT is the replacement of the conventional thermionic emission single X-ray source with a carbon nanotube (CNT) field emission X-ray source array, a pioneering technology with roots extending back two decades at UNC and the sole FDA-approved application of CNT in its 30-year history. Utilizing the electrical field, the CNT X-ray source array surpasses the heat dissipation issues inherent in conventional X-ray tubes and enables rapid image acquisition.

Our ms-CBCT harnesses nanotechnology for real-world engineering, offering MDCT-level imaging quality while maintaining the portability and affordability of CBCT. It sets a new benchmark for precision in dental imaging, elevates on-site diagnostic potential in ICUs and combat zones, and optimizes in-vivo tumor treatment planning in radiotherapy. Pioneered at UNC, the ms-CBCT is poised to revolutionize CT imaging in dental, emergency, and oncological care, improving the medical imaging quality across the diverse population throughout North Carolina and setting a precedent for global health advancement.”

Will Zahran


Tuition reduction and student loan debt: evidence from the North Carolina Promise

Will Zahran, doctoral candidate in education

“The UNC System enrolls over 160,000 undergraduate students across 16 public universities, and the average in-state borrower graduates with about $20,000 in student loan debt. The State of North Carolina plays an important role in ensuring higher education is affordable for students who want to attend. Financial aid policy at the state level determines the amount of assistance available to students, thus making a college degree attainable for those who may struggle to afford it.

In 2018, the NC General Assembly launched the NC Promise Tuition Plan. This financial aid program lowered tuition to $500 for in-state students at three universities: Elizabeth City State University, UNC-Pembroke, and Western Carolina University. The goal of a policy like NC Promise is to encourage students to enroll and graduate while taking on as little debt as possible.

My research explores the impact of this new policy on enrollment and student loans at the three Promise universities. Preliminary findings suggest that NC Promise increased enrollment among transfer students and decreased borrowing among middle-income students. These findings can help us better understand the effect of tuition subsidies on improving the design of financial aid policy in the future.”