CEC faculty research

Alison Evans Cuellar, PhD, MBA

Interprofessional George Mason researchers awarded more than $1 million to improve outcomes for patients with depression

Jennifer Pocock — Tue, 10 Dec 2024 18:25:35 +0000

Interprofessional George Mason researchers awarded more than $1 million to improve outcomes for patients with depression Jennifer Pocock Tue, 12/10/2024 - 13:25

Researchers Farrokh Alemi and Kevin Lybarger receive ��AV’s first Patient-Centered Outcomes Research Institute (PCORI) award to develop innovative Artificial Intelligence (AI) technology, including large language models, for improving antidepressant recommendations.

Farrokh Alemi and Kevin Lybarger

AI will soon receive a dose of empathy with the goal of helping to match people with depression to their best-fit medication. A team led by Farrokh Alemi, a professor in the College of Public Health (CPH), and Kevin Lybarger, an assistant professor in the College of Engineering and Computing (CEC), received $1,049,998 in research funding from the Patient-Centered Outcomes Research Institute (PCORI) to continue their work on developing an AI system that helps patients find the right depression medications.

With this funding support, Co-PIs Alemi and Lybarger will hone large language models (LLMs) to address known challenges in AI, including mitigating biases, reducing the potential for inaccurate information, and incorporating an empathetic tone, according to Alemi.

The new study will introduce an innovative way for AI to help patients make medication decisions. The AI system will engage patients in natural-language conversations to collect information about their medical history. The system will draw upon more than 10 million patient experiences with 15 different oral antidepressants and a National Institutes of Health All of Us database, which includes records from more than 80,000 participants with major depressive disorders, to help create a plan that is statistically likely to succeed. Alemi and Lybarger believe this will help alleviate the trial and error that can lead to negative patient outcomes.

The researchers will also introduce a first-of-its-kind patient simulator capable of mimicking various medical, linguistic, and behavioral characteristics. This simulator will be used to test and refine the AI system by simulating diverse patient scenarios, including infrequent but critical events such as suicidal ideation, to ensure the system’s recommendations are safe, culturally sensitive, and empathetic.

“This study was selected for its potential to address a high-priority methodological gap in patient-centered comparative clinical effectiveness research,” said PCORI Executive Director Nakela L. Cook. “We look forward to following the study’s progress and working with George Mason to share the results.”

This is the first PCORI-funded study that George Mason has received. “Depression is a major public health problem and we are excited to see the development of new AI-based decision tools, leveraging the multidisciplinary talents of our college to help tackle it,” said CPH Associate Dean of Research Alison Cuellar.

"This innovative study promises to generate methodologies for using AI for medical decision-support and for empowering patients to make critical health decisions beyond mental health,” says Özlem Uzuner, chair of CEC’s Department of Information Sciences and Technology.

This study is one of the latest funded by PCORI to examine which medical treatments work best, where and when treatment falls flat, and how to address the gaps. These studies deliver results that guide researchers in planning future studies and provide patients, their caregivers, and clinicians with the evidence-based information needed to make better-informed health and health care decisions.

In This Story

Farrokh Alemi, PhD

Kevin Lybarger

Özlem Uzuner

Research at George Mason

Topics

grants

Depression

antidepressants

natural language processing

Artificial Intelligence

Strategic Direction

Mason professors are researching hacker psychology to defend against cyberattacks

Colleen Rich — Thu, 02 May 2024 13:39:13 +0000

Mason professors are researching hacker psychology to defend against cyberattacks Colleen Rich Thu, 05/02/2024 - 09:39

A team of ��AV researchers is probing the psychology behind cyberattacks as part of a U.S. intelligence community program aimed at turning the tables on hackers.

Illustration by Getty Images

As the prevalence and severity of cyberattacks continue to grow, the Intelligence Advanced Research Project Activity (IARPA) has turned its focus on how best to exploit the weakest link in cyberattacks: the human factor.

Under a new IARPA program, researchers hope to better understand cyber attackers’ cognitive vulnerabilities and decision-making biases and use those vulnerabilities to derail future attacks.

Researchers Daniel Barbará, Giuseppe Ateniese, and Gerald Matthews were recently selected as part of a broader team of computer science, cybersecurity, and psychology experts to forge new research pathways and deliver cutting-edge technology as part of IARPA’s Reimagining Security with Cyberpsychology-Informed Network Defense, or ReSCIND, program.

Daniel Barbara. Photo by Office of University Branding

The team of researchers will build defensive tools that first cue in on hackers’ human limitations and use those weaknesses to delay or derail the attack while it is underway.

“You want to make them waste their time,” said Barbará, a computer science professor at George Mason’s College of Engineering and Computing. “The more they waste their time, the least damage they’re going to do.”

This can be accomplished by luring hackers with decoys such as false networks or documents to distract them.

But the trick is two-fold. The decoys must first and foremost appear to be real. They also need to entice the hackers away from their original aim. The latter is where understanding the psychological factors that influence hackers is essential.

As part of the first phase of the ReSCIND program, researchers will aim to fill gaps that exist in the current understanding of human cognition and decision making that influence cyber attackers’ behavior.

“It’s a challenging topic to address because hackers, of course, tend to be somewhat secretive,” Matthews, a professor of psychology at George Mason, said. “There aren’t many opportunities to study hacker psychology.”

Giuseppe Ateniese. Photo provided

Matthews said the current understanding of hackers’ behavior that provides the baseline for their research comes from several areas of study in psychology. Key among those areas is human performance and in particular how emotional states might influence performance.

“Hackers themselves are under pressure and potentially anxious about getting caught,” Matthews said. “They’re anxious about looking foolish to the people that they are working with.”

Cultural factors that motivate hackers are also important to consider and may vary greatly among hackers. Thrill-seeking college-age hackers, for example, would have different cultural norms and motives than highly trained professionals acting on behalf of a nation-state adversary, Matthews said.

Researchers hope to further understand the full scope of psychological factors that influence hackers, including how to measure, predict, and induce their cognitive vulnerabilities.

“There’s a certain amount of psychology that allows you to link the emotional reactions that hackers might have to cognitive biases and other vulnerabilities in performance,” Matthews said. “So, in this first part of the research, we’re trying to sketch out what some of those vulnerabilities might be.”

As part of the second phase, researchers will further define when cyberpsychology-informed defenses can best be used and how to determine the success of those defenses. The final phase will focus on modeling, adapting, and automating those defenses.

Ateniese, a computer science professor and eminent scholar in cybersecurity, said the ReSCIND program reflects the growing importance of cyberpsychology research in shaping emerging technology.

Gerald Matthews. Photo provided

“I see a myriad of excellent applications, not just this project,” Ateniese said. “As you can imagine, people today are building AI systems that either mimic or seek to improve upon human behavior. So, the psychology perspective is very intriguing.”

The ReSCIND program will run for nearly four years and is being carried out through research contracts awarded across five teams.

Barbará, Ateniese, and Matthews’ research will contribute to a ReSCIND contract awarded to SRI International, an independent nonprofit research institute headquartered in California.

The George Mason team will work alongside experts from the Florida Institute for Human and Machine Cognition, Margin Research, Research and Assessment Design: Science Solution, Two Six Technologies, University of Florida, and Virtual Reality Medical Center.

In many ways, the project is a natural progression for the three professors who have worked together on several previous projects requiring a multidisciplinary approach.

They were first introduced in 2021 by Amarda Shehu, a computer science professor and co-director at the time of the George Mason’s transdisciplinary Center for Advancing Human-Machine Partnerships (CAHMP).

A call for proposals from Virginia’s Commonwealth Cyber Initiative for a project that sought to bridge cybersecurity and human factors research to help users build secure passwords immediately brought to mind Barbará, Ateniese, and Matthews’ expertise.

“I always had the agenda of putting teams together and finding some funding opportunities so that then they could obtain preliminary results through which to demonstrate credibility for larger projects,” Shehu said.

The match has led to a series of successful projects by the team, including the Commonwealth Cyber Initiative password project and a project focused on distinguishing authentic videos from deepfakes.

“The IARPA project is, in some sense, an example of the culmination of an activity, how you put a team together,” Shehu said. “They find some funding so that they can start that relationship and then that kind of blossoms into a larger project. It's really a perfect example of what we want to see in […] in general at Mason in terms of transdisciplinary research and the fruit of that research.”

Shehu, now associate vice president for research for Mason’s Institute for Digital Innovation, said bringing teams together with broad collective expertise is critical to solving the most complex impediments to technological progress.

“The most challenging problems nowadays don't reside specifically within one discipline,” she said. “They bridge disciplines.”

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In This Story

Amarda Shehu

Daniel Barbará

Giuseppe Ateniese

Mason receives $4.85 million gift to increase intimate partner violence detection and reporting

Colleen Rich — Tue, 05 Mar 2024 15:38:51 +0000

Mason receives $4.85 million gift to increase intimate partner violence detection and reporting Colleen Rich Tue, 03/05/2024 - 10:38

��AV today announced an anonymous $4.85 million gift to advance groundbreaking research on bruise and injury detection for individuals who experience interpersonal violence.

The research team (from left) Janusz Wojtusiak, Katherine Scafide, and David Lattanzi. Photo by Ron Aira/Office of University Branding

The funding will help develop new tools in imaging technology using a light source that is five times better than white light for identifying and visualizing bruising across all skin tones for use by forensic nurses, social service providers, and law enforcement.

“This single largest gift to support research in the College of Public Health’s history underscores Mason faculty’s leadership in life-changing work affecting those who experience interpersonal violence,” said Melissa J. Perry, dean of the College of Public Health. “A gift of this magnitude brings transformative resources to Mason’s cross-disciplinary research and collaborative approach that takes ground-breaking research to new heights with the potential for greater use and impact.”

Mason’s acclaimed interdisciplinary research in using Alternate Light Sources for bruise detection, as featured on NBC Nightly News, is led by researchers Katherine Scafide, David Lattanzi, and Janusz Wojtusiak. The funding will expand the team’s bruise detection system that leverages artificial intelligence (AI), imaging and light technologies, forensic reports, and clinical expertise to increase data collection and access to care for trauma victims. The technology can be used across all skin tones and responds to deficits in the identification of physical injuries particularly among people with darker skin tones.

"By improving documentation of physical trauma, we hope to address disparities in clinical care which can lead to improved healthcare for all as well as legal recourse for all survivors of violence," said Scafide, forensic nurse, research leader, and an associate professor of nursing in Mason’s College of Public Health. “This gift expands Mason’s leadership in developing new technologies to empower vulnerable communities.”

One in three women worldwide experience physical trauma at the hands of an intimate partner or stranger. In the United States, more than 10 million women and men grapple with intimate partner violence each year. Among domestic violence survivors, bruises and soft tissue trauma are the most reported injuries. When injuries are accurately documented, survivors are more likely to participate in the criminal justice process, according to recent studies on interpersonal violence and reporting. In addition, family and partner violence and elder abuse can lead to a host of other public health issues, such as infectious and noninfectious diseases, mental health trauma, and reproductive health problems.

"A vital piece to success is ensuring that any AI tool has access to in-depth data from all skin tones and skin characteristics alongside human expert analysis,” said Lattanzi, an associate professor in the Sid and Reva Dewberry Department of Civil, Environmental, and Infrastructure Engineering in the the College of Engineering and Computing.

Supporters working on ending domestic violence commended the announcement.

Ruth Glenn, president of Survivor Justice Action, applauds the groundbreaking work. “In a nation where domestic violence disproportionately impacts communities of color, this innovative research holds immense promise. By prioritizing inclusivity and recognizing the unique challenges faced by survivors with darker skin tones, Scafide’s research aligns seamlessly with our vision to end domestic violence in our lifetime. Continued research on this technology not only has the potential to revolutionize the identification of bruising in diverse populations but also signifies a vital step toward justice and empowerment for those who have long been marginalized. Survivor Justice Action stands firmly in support of initiatives that demand systems change and establish resources for survivors and advocates.”

“The Scafide team’s research and findings are revolutionizing medical forensic examinations. The ability for medical professionals to visualize and identify previously ‘invisible’ injury substantively advances quality medical assessment and patient care. Visibility and documentation of trauma/ injury provide valuable forensic corroboration for law enforcement and the courts to hold offenders accountable,” said Ann Burdges, CEO of End Violence Against Women International.

This project is led by Mason’s College of Public Health in collaboration with the College of Engineering and Computing. More information on the study can be found at bruise.gmu.edu.

Learn more about the project

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Campus News

College of Public Health

robotics and autonomous systems

Mason Momentum

Teaching humans to play safe

Nathan Kahl — Mon, 04 Mar 2024 21:02:44 +0000

Teaching humans to play safe Nathan Kahl Mon, 03/04/2024 - 16:02

Autonomous systems can be programmed to always make the logical, “best” decisions, given a set of circumstances. But what happens when human judgment and decision-making is introduced to a system? Xuan Wang, an assistant professor in ��AV’s Electrical and Computer Engineering Department, is asking this question as part of a recent $344,000 grant from the National Science Foundation.

Wang stressed that this research is particularly important given technologies on the horizon. “The operation of many real-world systems involves the co-existence of human and autonomous agents. Inadequate coordination among these agents can lead to significant performance degradation or safety risks.”

Wang is turning the idea of humans controlling machines on its head. “The key novelty of this research is, instead of thinking about how humans can program robots, we are thinking about the ways that the autonomous agents can impact humans," he says. "Assuming human response can’t be coded in the way we can control a robotic agent’s behavior, then how we can design the robot’s behavior so they're impacting human behavior in a way that is beneficial for the overall system?”

In one of Wang's simulations, a human and robot carry a cup of hot water, testing programmed guarantees so that when the cup spills, it only spills to the robot side of the board, protecting the human. Photo provided.

Because human agents, who are very diverse, use observations to see occurrences in the world around them and respond accordingly, traditional optimization approaches are less effective at predicting behavior. Wang says that he’ll use a framework relying on game theory, which assumes each agent has their own objective function, and that function is coupled with another agent’s decisions and actions. Then both human and autonomous agents ideally will optimize their overall behavior to coordinate across a whole system, creating a better output.

This human-response alignment mechanism is bidirectional, allowing for communication moving in opposite ways at the same time. For robots, they will investigate new approaches that allow them to adapt more intelligently to human behaviors with uncertainties; for humans, they will study how they can be incentivized during human-robot interaction so that human responses favor the efficiency and robustness of the entire system.

But how can systems—autonomous or controlled by humans—ever guarantee safety, say in the use of unpersoned vehicles?

Wang says, “When we are deriving safety criteria, there might be some uncertainties, so given the inputs of the system there will be an upper and lower bound that allows you to know what is the worst case that will happen. Given that, if all assumptions are satisfied, one can guarantee that there will be no crash.”

Wang and team are also working with the Army Research Lab to develop collaborative autonomous vehicles working in unknown environments, ensuring the vehicles can coordinate and gain advantage when there are potential threats in the environment.

In This Story

Xuan Wang

Topics

Department of Electrical and Computer Engineering

human-computer interaction

Artificial Intelligence

National Science Foundation

Tech Talent Investment Pipeline (TTIP)

TTIP

Tech Talent Investment Program

New noninvasive tests may help pediatric heart recipients

Nathan Kahl — Thu, 15 Feb 2024 15:08:18 +0000

New noninvasive tests may help pediatric heart recipients Nathan Kahl Thu, 02/15/2024 - 10:08

Each year, approximately 500 children in the U.S. undergo heart transplantation. These children face considerable stress.

Undergoing a biopsy—an invasive procedure using a catheter to remove a piece of the transplanted heart to test it—is just one way such patients are poked and prodded. Cardiac biopsies are a necessary evil, serving as the primary way doctors detect if a heart is likely to be rejected. But now ��AV and the Inova Health System are teaming up to develop ways to make that determination with noninvasive techniques.

Jason Goldberg. Photo provided

“On average, children pediatric heart transplant patients undergo approximately 10 biopsies within the first year of transplant…and more if they have rejection,” said Jason Goldberg, MD, MS, a pediatric cardiologist and research fellow at Mason. “That's a big deal, especially since taking a child to the hospital is no small thing. They have to go under anesthesia, they have to have needles stuck in them. It's quite traumatic, and diagnosing rejection in a noninvasive manner may help start treatment before the patient is sick and not feeling well.”

Cardiologist Palak Shah, MD, an adult heart-transplant specialist who serves as Goldberg’s research mentor at Inova, has worked with colleagues both at Inova and Mason to evaluate the potential of microRNA (miR) to provide clues on whether heart transplant recipients are at risk for rejection. miR are small, noncoding RNA molecules that impact the regulation of gene-expression.

Shah and his team published a paper in 2022 that was cause for optimism. The researchers found that “miRs are promising genomic biomarkers in cardiovascular medicine, have the potential ability to detect heart transplant rejection, and may provide mechanistic insights into molecular pathways modulated during rejection.”

“MicroRNA is a type of transcription factor, which is a protein that turns specific genes ‘on’ or ‘off’ by binding to nearby DNA,” explained Goldberg. “And it's encoded to a certain degree to do what the body needs, so when you measure the microRNA, you can get a sense of what the body is doing—essentially it's a molecular biomarker. What Palak and others found is that there are microRNA signatures correlating with heart transplant rejection.”

Goldberg is now using the technique to test children who have received new hearts. He and his colleagues at Mason and Inova received a grant from the Enduring Hearts Foundation, which includes collaboration with colleagues at the University of Pittsburgh Medical Center who have bio-banked blood samples taken at the time of biopsy. The biomarkers are validated by looking simultaneously at the microRNA taken at the same time as a rejection or nonrejection biopsy.

Testing microRNA allows doctors to determine the likelihood of a successful heart transplantation

The new pediatric developments are being supported by a partnership between Inova and the Mason Statistics Collaboration Core (SCC), which is providing the mircoRNA analysis. This and other collaborative projects require machine learning and other advanced statistical techniques utilized by Mason faculty and graduate students.

Goldberg said that the collaboration is mutually beneficial. “Mason has great research and science but no medical school, whereas Inova has great medicine but lacks significant biomedical academic partnership," said Goldberg. "With the two organizations working together it creates a lot of runway for research.”

Goldberg is one the first members of a postdoc program for Inova clinician-scientists interested in developing skills in statistics and data science. “I'm a pediatric heart transplant physician and I've been taking care of patients for nearly 15 years,” he said. “But I was at a point in my career where I really caught the research bug, and it hasn’t gone away."

Palak, Goldberg's mentor, has ongoing collaborations with Jiayang Sun, chair of Mason's Department of Statistics, and Carolyn Drews-Botsch, chair of the Department of Global and Community Health in Mason's College of Public Health. Sun is the Mason PI and Drews-Botsch is the Co-PI for this special joint postdoc program with Inova Health System.

“This pioneering program between Mason and Inova uniquely trains the next generation of medical research scientists in collaborative research and some essentials in data science, statistics, or epidemiology to address the challenges of the AI and information revolution," said Sun. The program features dedicated mentors from Mason in the fields of statistics, epidemiology, and global health, along with top physicians and researchers at Inova.

Goldberg is enthused about the new development, and most importantly, the increased longevity it may bring to young patients with critical heart disease. “When I was in my cardiology fellowship, we thought that the big change in heart transplantation would be that we wouldn't have to do it anymore, that there would be stem cells and other fancy machines that wouldn't require the use of donor organs. But time and time again, nothing has really worked to replace heart transplantation.

“It has become clear that the next frontier for our patients includes personalized medicine where molecular biomarkers and therapies can evaluate ongoing pathology and define specific treatments before significant illness develops. I am proud to be part of this work at Mason and Inova.”

In This Story

Jiayang Sun

Carolyn Drews-Botsch, PhD, MPH

Topics

Statistics Collaboration Core

College of Public Health

Institute for a Sustainable Earth (ISE)

A $6 million NSF grant will translate research into practice to help local communities become climate-resilient

Colleen Rich — Tue, 23 Jan 2024 18:50:38 +0000

A $6 million NSF grant will translate research into practice to help local communities become climate-resilient Colleen Rich Tue, 01/23/2024 - 13:50

��AV scientists and partners will leverage their climate expertise and the university’s resources into broader societal implications, thanks to a $6 million grant from the National Science Foundation (NSF) that is going to translate research into practice to support the creation of climate-resilient communities across Virginia.

Mason researcher Celso Ferreira (far right) and President Gregory Washington take Congresswoman Abigail Spanberger on a tour of Mason's Flood Hazards Research Lab. Photo by Evan Cantwell/Office of University Branding

The funding from the NSF’s Accelerating Research Translation (ART) program will allow Mason to expand its capabilities and capacity for translating research into real-world practical applications, with the creation of programming that will allow Mason faculty to serve communities across the commonwealth—especially within the state’s underserved regions—by co-producing science-based solutions that help them increase their resilience to climate change.

The four-year cooperative agreement, “ART: Translating Research to Practice to Create Climate-Ready Communities Across Virginia,” begins Feb. 1, and will allow Mason faculty and their nonprofit partner, the Center for Climate Strategies, to work with local municipal governments and community partners to produce science-based solutions that will create sustainable, community resilience to the impacts of climate change.

The project proposes two initial seed translational research projects, focusing on the co-production of solutions to mitigate flood hazards and reduce the impacts of urban heat on frontline communities. The latter comes on the heels of the world’s warmest year on record in 2023. Faculty will have the opportunity to propose additional translational research projects that address other climate impacts and response capabilities needed by Virginia communities to become climate-ready.

Mason’s Jeremy Campbell leads a discussion on local resiliency planning with staff from the Northern Virginia Regional Commission at a workshop held by the Virginia Climate Center in March 2023. Photo by VCC

“This really gives universities a chance to have an impact,” said Leah Nichols, the project’s principal investigator and the executive director of Mason’s Institute for a Sustainable Earth. “I think it’s going to help us start to institutionalize things that until now had been one-offs.”

Mason was one of 18 schools to have been awarded an ART cooperative agreement. The NSF overall investment of more than $100 million will enable academic institutions to accelerate the pace and scale of translational research that will grow the nation's economy.

“NSF endeavors to empower academic institutions to build the pathways and structures needed to speed and scale their research into products and services that benefit the nation,” said NSF Director Sethuraman Panchanathan. “The [ART program] identifies and champions institutions positioned to expand their research translation capacity by investing in activities essential to move results to practice.”

Mason’s ART program leverages the model already created by the Virginia Climate Center (VCC)—which was initially established by a $2 million Community Project grant sponsored by Congressman Gerry Connolly (D-VA) – since its inception in 2022 for the necessary engagement infrastructure. That includes targeted outreach to individual community leaders and other key influencers in the hopes of creating the kind of collaborative relationships necessary to figure out what each community’s specific needs are.

Other co-PIs on the Mason project include Jim Kinter, a professor in the Climate Dynamics PhD Program and the director of both Mason’s Center for Ocean-Land-Atmosphere Studies within the College of Science and the Virginia Climate Center; Celso Ferreira, an associate professor within Mason’s College of Engineering and Computing and the director of the Flood Hazards Research Lab; Luis Ortiz, an assistant professor in the Department of Atmospheric, Oceanic and Earth Sciences within the College of Science; and Tom Peterson, the CEO of the Center for Climate Strategies. Other entities involved include MN Associates Inc., which will monitor’s the program’s implementation and progress, and the University of Kentucky, which is serving as the project’s mentoring institution. Pairing awardees with mentor institutions that have an established translational research ecosystem is one of the unique features of the ART program.

Current research that can be brought to bear on local community concerns includes, but is not limited to risk and vulnerability assessment, the development and deployment of new adaptive capacities through modeling, simulating, predicting and projecting climate variability and change, including downscaled global observational and modeling data sets, and the development of solutions to close vulnerability gaps by assessing needs for action and designing and evaluating new measures for local implementation.

Other aims include supporting faculty who wish to be involved and the creation of specific academic programming, such as specialized courses on key climate issues, a new climate action minor, and a graduate certificate program, for future workforce development.

“One very troubling aspect of the effects of climate change is that it has the biggest impact on underserved people and communities that are least able to address the issue,” Kinter said. “Mason, being the largest public university in Virginia, owes it to the residents of the commonwealth to understand the risks it faces and create innovative solutions to increase community resilience.”

Virginia bore the brunt of nine climate disasters in 2018 and 2019 alone, resulting in $1.6 billion of negative economic impact, according to the Secretary of Natural and Historic Resources.

Increasing community resilience to the effects of climate change is expected to help mitigate the impact and substantially reduce costs associated with damage from progressive climate change, extreme weather events, and other climate-driven effects, the researchers said.

“We’re really trying to understand what it is that [local communities] need from a scientific, technical, or research point of view through the lens of what is it that a university can provide,” Nichols said. “And once the climate-focused ART programs become well-established, we hope to extend this model to support the translation of research into practice in other sustainability domains as well.”

In This Story

Celso Ferreira

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Limiting leaking leachate

Nathan Kahl — Mon, 22 Jan 2024 17:42:27 +0000

Limiting leaking leachate Nathan Kahl Mon, 01/22/2024 - 12:42

Most Americans don’t think much about their trash once they’ve taken it outside of their home, which is a testament to our country’s efficient garbage management system.

Once that garbage truck rolls down the street, there’s a chance your trash is headed to one of the country’s roughly 3,000 operational landfills. And although it’s gone from your kitchen, the potential for that trash to then contaminate and harm people is something that must be carefully managed.

Kuo Tian, an assistant professor in the Sid and Reva Dewberry Department of Civil, Environmental, and Infrastructure Engineering at ��AV, recently received a grant from the U.S. Department of Agriculture to look at solid waste management service in rural locations, focusing on the potential health threats to groundwater in those areas.

Modern landfills have a composite liner system to collect leachate, a liquid that starts as rainfall (or melted snow) and that pools at the bottom of the landfill after filtering through waste, pulling out chemicals and pollutants from the material. Leachate is held by a liner system, comprising a geomembrane—which is very resistant to puncture and is usually black in color because of carbon added for strength—on top of a layer of clay or geosynthetic clay liner, which serves as a containment redundancy. Small punctures in the membrane are inevitable, but leak detection techniques allow operators to examine the liner as it is put in place, identifying even tiny holes, which can be fixed before waste is layered on top.

Mason researcher Kuon Tian and doctoral student Benjamin Matthew Stark collect leachate for analysis at the Berkeley County Landfill in West Virginia. Photo provided

Tian and his team will specifically examine the potential for PFAS leaking through the landfill liner system and contaminating nearby groundwater. PFAS—per- and polyfluorinated substances—are a group of chemicals used to make coatings for a variety of products and are commonly referred to as forever chemicals because they are persistent in the environment and in human bodies. Some evidence suggests they cause significant health problems.

The researchers will test both the types and concentrations of PFAS in leachate. “We want to assess the PFAS concentration over a year, looking at precipitation conditions, age of the landfill, and other factors,” Tian said.

The timing of the project is important, he says, because the EPA only recently created PFAS standards for drinking water, though there are currently no regulations to check PFAS concentrations in landfill leachates. Understanding how landfills may contribute to groundwater contamination will aid with landfill management moving forward.

According to Tian, a quality liner is critical. “A good liner will keep the leachate from migrating to the groundwater for hundreds or thousands of years.” So even if high PFAS levels are found, they may not pose an immediate risk. Further, he is concerned about PFAS migration to groundwater in older landfills, built prior to the early 1990s, which only use clay liners or in some cases lack liners entirely.

In addition to the research component, the grant contains funding for teaching elements. Once results from the research are confirmed, findings will be shared with local landfill operators and stakeholders.

In This Story

Kuo Tian

Topics

civil and infrastructure engineering

Mushrooming feats of engineering success

Rena Malai — Tue, 24 Oct 2023 13:12:44 +0000

Mushrooming feats of engineering success Rena Malai Tue, 10/24/2023 - 09:12

In This Story

Emma (Xijin) Zhang

It’s important not to crowd mushrooms in a pan, otherwise they won’t cook properly, according to well-known American chef Julia Child. But Child likely didn’t realize that those mushrooms crowded together can accomplish impressive feats of engineering within concrete structures.

Xijin “Emma” Zhang, assistant professor in civil engineering at ��AV, is working on exploring the use of fungi spores within infrastructures. The practice is relatively new, and Zhang is the first professor within Mason’s Sid and Reva Dewberry Department of Civil, Environmental, and Infrastructure Engineering to work on incorporating fungi materials for sustainable building purposes.

“The research I’m very passionate about is exploring how to utilize natural resources to solve challenges within civil engineering,” Zhang said. “Although I am not a biologist, studying these natural solutions to engineering can help make complex solutions to infrastructure challenges simple.”

In Zhang’s research, the fungal fibers that make up the "stem" part of the mushroom get mixed into the concrete mixture before the building process starts. If cracks later generate within the concrete structure, the air and moisture seeping through the cracks activate the fungi spores. The fungi fibers ‘bloom’ and produce chemical minerals. The strong fungal fibers and the chemical minerals help heal the cracks.

“The healing of the cracks is facilitated by the growth of the fungal fibers and the fungi’s productions of chemical minerals,” Zhang said. “This self-healing technology saves expensive and timely repairs to the structures.”

The fungi’s hydrophobic surface means just that—it repels water. This additional benefit prevents water from infiltrating concrete, deterring water-related distresses and improving the durability of the infrastructure.

Zhang is working on cultivating different fungi spores and testing what works best, as not all classes of fungi would necessarily work for cracks. She has discovered the fungi spores within oyster mushrooms have resilient fibers and can be developed to provide excellent properties in thermal insulation, while being safe for human beings to come in contact with.

She sees Mason as a hub of rich resources in research, collaboration, and connections. Being fairly new to the College of Engineering and Computing, Zhang is excited to partner with fellow colleagues in various fields, who are also interested in exploring the uses of fungi as a solution, beyond civil engineering.

“Fungi have many unknown properties, and I’m looking forward to exploring these types of green technology solutions,” she said. “If anyone is interested in joining me to collaborate, I hope they will reach out.”

Zhang can be reached at xzhang50@gmu.edu.

Topics

CEIE Success Stories

Department of Civil Environmental and Infrastructure Engineering (CEIE)

Big data may lead to safer roadways, lower emissions

Teresa Donnellan — Mon, 23 Oct 2023 16:26:19 +0000

Big data may lead to safer roadways, lower emissions Teresa Donnellan Mon, 10/23/2023 - 12:26

In This Story

Shanjiang Zhu

Anand Vidyashankar

Once, transportation officials made decisions based on household surveys performed roughly once per decade, which asked selected households to record their travel behavior on a given day. With the advent of smartphones, similar data became available roughly every few minutes. Now, with an increasing number of connected vehicles on the road, that data is available in nearly real time. CEIE professor Shanjiang Zhu is embracing this shift, exploring the capabilities of researchers with this massive amount of data.

With funding from the Virginia Department of Transportation (VDOT), Zhu and his research team, Anand N. Vidyashankar from the department of statistics and Chenfeng Xiong from the Civil and Environmental Engineering department at Villanova University, will reconcile the travel data from three different sources—surveys, smartphones, and connected vehicles—into invaluable travel information.

"In the past, we tried to understand travel behavior, which is critical for future investment decisions and also transportation policy, based on survey data,” Zhu explained. “Based on that, you understand, on average, where people have traveled, in what mode, with whom, and spent how much time there, uh what is the purpose for the trip, etc. Using that information, you can develop a model that basically can predict future scenario, like how congested the network could be in 2040; and that drives all the investment decisions and policy debates.” This method introduces problems of timeliness, as it can skip major events such as the COVID-19 pandemic, and human error, as people would not necessarily remember every detail of their travel on a given day.

The introduction of widespread smartphone use about ten years ago made the available data much denser, said Zhu, resulting in about one data point every three to five minutes. Each time a person’s smartphone app calls for location service, their location is automatically registered. Nevertheless, this method introduced a bias problem, as not everyone owns a smartphone and not everyone uses them often.

About a year ago, Zhu’s team won a competition hosted by VDOT to make the best possible use of connected vehicle data, basically newer vehicles like those with an “SOS” button installed. One drawback to the data currently is connected vehicles currently make up a relatively small share of vehicles on the road.

“But we have ways to make corrections from a statistical perspective, and then this gives you a much more accurate picture of traffic on the road,” said Zhu, adding “On average, it's one data point every three seconds. With such data, the accuracy and timeliness of travel demand models could be greatly improved.” Zhu noted his colleague Vidyashankar will be reviewing the data fusion to ensure a rigorous statistical approach.

The new data also opens the door for new safety studies, Zhu said, adding safety studies are currently based mainly on police reports after an accident has occurred. By using alternate data, such as how often a car’s brake deceleration rate exceeds a certain threshold or how hard a driver turns the steering wheel, dangerous locations might be addressed before an accident occurs. Zhu is interested in exploring the topic further using the dataset resulting from his current project.

Zhu foresees data from connected vehicles becoming increasingly important as more and more people adopt the technology. He said, “Now we are investing in the methodology part and seeing how we can make this connection more productive, to improve the driving environment, to make our roads safer, to make the driving experience better, and also to reduce our energy consumption and emissions."

Topics

transportation engineering

Big Data

big data analytics

Transportation Policy Operations and Logistics