Oct. 13, 2025
A brown basilisk missing both its entire left forearm and part of its right hind limb. Brian Hillen

A brown basilisk missing both its entire left forearm and part of its right hind limb. Brian Hillen

We are lizard biologists, and to do our work we need to catch lizards – never an easy task with such fast, agile creatures.

Years ago, one of us was in the Bahamas chasing a typically uncooperative lizard across dense and narrow branches, frustrated that its nimble agility was thwarting efforts to catch it. Only when finally captured did we discover this wily brown anole was missing its entire left hind leg. This astonishing observation set our research down an unexpected path.

That chance encounter led us to collaborate with over 60 colleagues worldwide to document what we suspected might be a broader phenomenon. Our research uncovered 122 cases of limb loss across 58 lizard species and revealed that these “three-legged pirates” – the rare survivors of traumatic injuries – can run just as fast, maintain healthy body weight, reproduce successfully and live surprisingly long lives.

To be clear, most lizards probably do not survive such devastating injuries. What we’re documenting are the exceptional cases that defy our expectations about how natural selection works.

A hefty green lizard with a noticeable mark where it's left 'arm' would have been poses on a tree branch

A four-horned chameleon missing its entire left forelimb in Cameroon appeared healthy when observed in the wild, despite the specialized gripping requirements of chameleons. Christopher Anderson

This discovery is startling because lizard limbs represent one of biology’s most studied examples of evolutionary adaptation. For decades, scientists have demonstrated that even tiny differences in leg length between individual lizards can mean the difference between life and death – affecting their ability to escape predators, catch prey and find mates.

Since subtle variations matter so much, biologists have long assumed that losing an entire limb should be catastrophic.

Yet our global survey tells a different story about these remarkable survivors. Working with colleagues across six continents, we found limb-damaged lizards across nearly all major lizard families, from tiny geckos to massive iguanas.

These animals had clearly healed from whatever trauma caused their injuries – likely accidents or the failed attempts of a predator to eat them. Perhaps most remarkably, we documented surviving limb loss even in chameleons, tree-climbing specialists whose movements seem to require perfect limb coordination.

Thriving, Not Just Surviving

The body condition of these lizards was most surprising. Rather than appearing malnourished, many limb-damaged lizards were actually heavier than expected for their size, suggesting they were successfully finding food despite their handicap. Some were actively reproducing, with females found carrying eggs and males observed successfully mating.

4 side by side X-ray images in black and white of small lizards each missing a limb

Limb damage can be fairly common in some lizard populations, such as these X-rays of brown anoles (Anolis sagrei) from the Bahamas. Jason Kolbe/Jonathan Losos

These findings force us to reconsider some basic assumptions about how evolution might work in wild populations. Charles Darwin envisioned natural selection as an omnipresent force, “daily and hourly scrutinizing” every feature.

But perhaps selection is more episodic than constant. Maybe sometimes limb length matters tremendously, while during other times – such as when food is abundant and predators are scarce – limb length matters less and three-legged lizards can flourish.

These lizard survivors showcase the incredible solutions that millions of years of evolution have built into their biology. Rather than being passive victims of their injuries, these lizards may survive by actively choosing safer habitats or hunting strategies, using smart behavior to avoid situations where their disability would be a disadvantage.

Biological Engineering in Action

Our research combines old-fashioned natural history observations with cutting-edge, biomechanical analysis.

We use high-speed cameras and computer software that can track movement frame by frame to analyze running mechanics invisible to the naked eye. This combination of field biology and laboratory precision allows us to understand not just that these lizards survive, but how they accomplish this remarkable feat.

When we tested the three-legged lizards’ athletic performance, the results defied expectations. Some animals were clearly impaired in their sprinting capabilities, but others actually ran faster than fully-limbed individuals of the same size across a 2-meter dash during our “Lizard Olympics.”

Researchers used computer software that automatically tracks movement patterns to analyze high-speed videos of lizards sprinting, such as this brown anole missing half of its right back leg. Christopher Anderson

High-speed video analysis revealed their secret: The speedy survivors compensate through creative biomechanical solutions. One brown anole missing half its hind limb dramatically increased its body undulation during sprinting, using exaggerated snakelike movements to compensate for the missing leg.

By documenting the unexpected – the seemingly impossible survivors – we’re reminded that nature still holds surprises that can fundamentally change how we think about life itself.The Conversation

 

This article is republished from The Conversation under a Creative Commons license. Read the original article.

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Authors:

James T. Stroud, assistant professor of Ecology and Evolution, Georgia Institute of Technology 

Jonathan Losos, William H. Danforth Distinguished University Professor, Washington University in St. Louis

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Shelley Wunder-Smith
shelley.wunder-smith@research.gatech.edu

Oct. 13, 2025
Grace Tang (Left) and Alison Onstine (Right) holding bacteria plates that spell "BIOL 4590" (Credit: Tang and Onstine)

Grace Tang (Left) and Alison Onstine (Right) holding bacteria plates that spell "BIOL 4590" (Credit: Tang and Onstine)

A collection of the undergraduate students who co-authored the paper. (Credit: Tang and Onstine)

A collection of the undergraduate students who co-authored the paper. (Credit: Tang and Onstine)

This fall, 20 Georgia Tech students published a peer-reviewed scientific paper — the culmination of work done during a semester-long laboratory course. During the semester, students analyzed genomes sequenced from marine samples collected in Key West, Florida — doing hands-on original bioinformatics research on par with graduate students and working with bioinformatics tools to explore drug discovery potential.

The course, BIOS 4590, is a research project lab for senior biology majors that provides an opportunity for professors to share their expertise with students in a hands-on environment. In his class, Associate Professor Vinayak (Vinny) Agarwal, who holds joint appointments in the School of Chemistry and Biochemistry and School of Biological Sciences, aimed to introduce undergraduates to advanced bioinformatics tools through applied research using new-to-science raw data. 

The resulting paper, “Phylogenomic Identification of a Highly Conserved Copper-Binding RiPP Biosynthetic Gene Cluster in Marine Microbulbifer Bacteria,” which was recently published in ACS Chemical Biology, involves the historically understudied genus of Microbulbifer, a type of bacteria often associated with sponges and corals. These microbial communities are rich sources of natural products, small biological molecules often associated with medicine and drug discovery. 

"This class, and the resulting research, is a testament to the transformative power of hands-on learning,” says Susan Lozier, dean of the College of Sciences, Betsy Middleton and John Clark Sutherland Chair, and professor in the School of Earth and Atmospheric Sciences. “The success of this course — and the students’ remarkable achievement — reflects Georgia Tech's commitment to fostering curiosity, collaboration, and scientific rigor and to empowering the next generation of scientists and leaders."

Funded by Agarwal’s 2023 National Science Foundation CAREER grant and Camille and Henry Dreyfus Foundation Teacher-Scholar award, the class also received support from leadership in the College of Sciences, School of Biological Sciences, and School Chemistry and Biochemistry. The study’s lead author, graduate student Yifan (Grace) Tang, served as the class teaching assistant, and was funded in part by a Biochemistry and Biophysics Graduate Assistance in Areas of National Need fellowship

“The students in this class are working on important, novel work — this cohort worked with real genomic data that had never been sequenced before,” she says. “Typically, researchers might work with one or two genome sequences, but we provided students with 42 — this might be the first time anyone has looked at Microbulbifer at such a wide scope.” 

From classroom to publication

To prepare for the class, Tang worked alongside Laboratory Manager Alison Onstine, who manages the School of Biological Sciences teaching laboratory spaces, to sequence the Key West bacterial genomes.

“Our work in the Agarwal Lab is in natural product discovery. We focus on finding new pharmaceutical drugs through marine bacteria — but with a bioinformatics spin,” Tang explains. “We wanted to bring this type of experience to undergraduates, so we gave fully sequenced genomes to students and asked them to look for potential properties.” 

Throughout the class, students learned different techniques for analyzing bacterial genome sequences and extracting data with various tools — gaining both lab and computational skills through hands-on experiences, live demos, and troubleshooting sessions. 

“The highlight was showing students just how much we can learn about a bacterial genus, especially one that hasn’t been studied at this scale before,” Tang shares. “This is a growing field, so there are so many opportunities for students to make meaningful contributions while learning new skills.”

Empowering future students

For many students, it was their first time using these types of tools, but Agarwal says that it’s something they'll likely encounter in both industry and research. He sees this type of research experience as especially helpful for seniors, who are often deciding between entering the workforce or continuing their education.

“Bioinformatics is increasingly important for analyzing big data. Students need the ability to manipulate and understand data using computational tools, and this class plays an important role in familiarizing them with this process,” he shares. “Our goal is to demystify research and give students the confidence and tools for both graduate school and for the workforce after graduation.”

The class will be offered for a third time in Fall 2026. While the exact course of research hasn’t yet been decided, “we always aim for something new that can produce publication-quality research — students don’t repeat past year’s work,” Agarwal says. This recent cohort of students built on the success of 18 undergraduates who took the class in 2023, who also published a paper. “This course truly underscores Georgia Tech’s commitment to pioneering meaningful undergraduate experiences — no other peer institution I know of is exposing undergraduates to bioinformatics at this level.”

 

Funding: NSF CAREER and the Dreyfus Foundation

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Written by Selena Langner

Oct. 07, 2025
Mark Styczynski in lab

Imagine if building new medicines or sustainable materials were as straightforward as snapping together LEGO® bricks. That’s the goal of a new project led by the Georgia Institute of Technology that could help transform the future of biomanufacturing.

The project, headed by Professor Mark Styczynski in Georgia Tech’s School of Chemical and Biomolecular Engineering (ChBE@GT), recently received a $9.2 million grant from the National Science Foundation Directorate for Technology, Innovation and Partnerships (NSF TIP) to accelerate the adoption of cell-free systems in biomanufacturing.

Promising Technology

Biotechnology has largely relied on living cells for production of products such as medicines, fragrances, or renewable fuels. But working with living cells can be complex and expensive.

Cell-free systems, by contrast, strip biology down to its essential parts, the enzymes and molecules that carry out life’s chemical reactions. This can simplify and speed up biomanufacturing, making it easier to scale.

The challenge, Styczynski explained, is that most cell-free projects still require custom-built setups. “Right now, engineering biology is like reinventing the wheel for every application,” he said. “You have to figure out how all the parts fit together each time. We want to change that by making ready-to-use modules that work right out of the box.”

Styczynski’s project, called Meta-PURE (PUrified Recombinant Elements), will create eight standardized modules, each designed for a key function in cell-free systems, such as generating energy, producing proteins, or assembling complex molecules.

“Like interchangeable puzzle pieces, these modules can be mixed and matched to support different applications,” Styczynski said.

Demonstrating Uses

His team will demonstrate the system’s versatility by producing santalene (a plant-derived fragrance used widely in consumer products), GamS protein (a tool that can improve cell-free processes), and a bacteriophage (a virus that can be safely used in research and the development of new therapeutic treatments).

These examples highlight the technology’s potential across industries ranging from pharmaceuticals and agriculture to chemicals and sustainable materials.

“We want to make these tools so that someone in industry can create their molecule or product more quickly and efficiently, and get it out the door,” Styczynski said. 

“Right now, cell-free systems are mostly limited to high-value products because the cost is too high. The goal is to drive costs down and productivity up, so we can move closer to commodity chemicals like biofuels or monomers for polymers, not just niche applications. One of our partners recently developed a butanol process that shows where this can go,” he said.

NSF Initiative

Styczynski’s team is one of four recently awarded an inaugural investment of $32.4 million to help grow the U.S. bioeconomy. The initiative is called the NSF Advancing Cell-Free Systems Toward Increased Range of Use-Inspired Applications (NSF CFIRE).

“NSF is resolute in our commitment to advancing breakthroughs in biotechnology, advanced manufacturing, and other key technologies of significance to the U.S. economy,” said Erwin Gianchandani, assistant director for NSF TIP. “The novel approaches from these four CFIRE teams will speed up and expand the adoption of cell-free systems across a variety of industries and ensure America’s competitive position in the global bioeconomy.”

Collaborative Effort

While ChBE@GT is the lead, Meta-PURE is a broad collaboration with partners across academia, industry, and government. Co-principal investigators include Paul Opgenorth, co-founder and vice president of development at the biotech firm eXoZymes; Nicholas R. Sandoval, associate professor of Tulane University’s Department of Chemical and Biomolecular Engineering; and Anton Jackson-Smith, founder of the biotech startup b.next.

Meta-PURE will also train graduate students and postdocs in partnership with industry, government, and other universities, helping prepare trainees to be the future of a highly interdisciplinary U.S. bioeconomy. The team will also engage the scientific community on the implementation of metrics and standards in cell-free biotechnology to better facilitate broad adoption and interoperability of not just the results of the Meta-PURE project, but of cell-free efforts more broadly. 

 

 

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Brad Dixon, braddixon@gatech.edu

Sep. 30, 2025
Nathan Wallace in the lab

Nathan Wallace testing the microprocessor-powered leg in the Exoskeleton and Prosthetic Intelligent Controls (EPIC) Lab at Georgia Tech. Submitted photo.

Nathan Wallace was born with proximal femoral focal deficiency, a congenital limb disorder, which led to the amputation of his left foot at 8 months old. He was fitted for his first prosthetic at 13 months.  

Now, the third-year biomedical engineering student is using his life experience to develop advanced prostheses as a member of the Exoskeleton and Prosthetic Intelligent Controls (EPIC) Lab. Wallace is part of the development and machine learning teams on an ongoing vertically integrated project led by Associate Professor Aaron Young and senior research scientist Kinsey Herrin. The teams are engineering a microprocessor-powered leg and ankle capable of mimicking gait and providing stability in walking patterns across various surfaces. 

Traditional prosthetics, like the one Wallace uses, don’t provide ankle flexion, but the current iteration of the lab’s leg offers something that he views as an evolution of products on the market today. The latest tests allowed Wallace, while wearing the leg, to walk up a ramp with the ankle and knee adapting to the slope.  

“A lot of our power comes from the ankle, and our version of the leg better recreates a complete gait cycle, which includes the knee and ankle flexion and everything in between. With my current prosthetic, I don’t have that same gait control, so I’m swinging my foot around and overcompensating on my right leg. With our leg, I’m walking up the ramp normally, and it’s creating a movement that I've never felt before,” he said.  

Along with the improved performance of the leg, Wallace and the team intend to use machine learning to assist in fitting patients with prosthetics that meet their unique needs. 

“We're trying to get away from patients having to spend hours in an office tuning a prosthetic to their preferences. Instead, it allows the machine learning model to learn as the person walks on it. This can help reduce costs related to both time and personnel,” he said.  

Growing up, Wallace was an active child at recess and eventually became a high school wrestler. While there were times he felt he couldn’t keep up with his classmates, he found ways to adapt. He credits his condition for helping him develop a strong work ethic and a desire to help others find the same confidence he has found as he’s gotten older.  

“Learning to embrace who I am has made me the person I am today. It’s given me perspective and a capacity for empathy and sympathy for others in the disabled community,” he said. “My past and my condition have driven me to where I am today, and I feel privileged to be at Georgia Tech. It touches a special place in my heart to know that this kind of work is going on, and that I can be a part of it.”  

Outside of the lab, Wallace is a member of the student organization Tikkun Olam Makers, which develops open-source solutions for members of disabled communities. He also creates props for DramaTech, and, continuing to push himself beyond his comfort zone, he recently starred in the student-run theater’s production of Eurydice

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Steven Gagliano – Institute Communications

Sep. 23, 2025
man baring chest an holding a patch against his skin

Heart failure remains one of the most challenging conditions to monitor outside the clinic. Patients may experience changes in symptoms, such as fatigue or shortness of breath, between visits, yet many current devices provide limited data, leaving physicians without continuous insight into heart function.

“Despite advances in digital health, continuous monitoring of the heart’s mechanical function has remained difficult outside clinical settings,” said Omer Inan, researcher and entrepreneur at Georgia Tech. “Patients and physicians have long needed a tool that provides deeper, real-time insights into heart performance without invasive procedures. We decided to tackle that problem head-on with a wearable device.”

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Sep. 24, 2025
Researchers show off a lung-on-a-chip that has an immune system. Long term, this technology could lead to highly personalized medicine

Ankur Singh and Rachel Ringquist point to the microscopic lung-on-a-chip that has a built-in immune system.

On a clear polymer chip, soft and pliable like a gummy bear, a microscopic lung comes alive — expanding, circulating, and, for the first time, protecting itself like a living organ. 

For Ankur Singh, director of Georgia Tech’s Center for Immunoengineering, watching immune cells rush through the chip took his breath away. Singh co-directed the study with longtime collaborator Krishnendu “Krish” Roy, former Regents Professor and director of the NSF Center for Cell Manufacturing Technologies at Tech and now the Bruce and Bridgitt Evans dean of engineering and University Distinguished Professor at Vanderbilt University. Rachel Ringquist, Roy’s graduate student, and now a postdoctoral fellow with Singh, led the work as part of her doctoral dissertation. 

“That was the ‘wow’ moment,” Singh said. “It was the first time we felt we had something close to a real human lung.”

Lung-on-a-chip platforms provide researchers a window into organ behavior. They are about the size of a postage stamp, etched with tiny channels and lined with living human cells. Roy and Singh’s innovation was adding a working immune system — the missing piece that turns a chip into a true model of how the lung fights disease.

Now, researchers can watch how lungs respond to threats, how inflammation spreads, and how healing begins.
 

The Human Stakes

For millions of people struggling with lung disease, everyday life can feel nearly impossible, whether it’s climbing stairs, carrying groceries, or even laughing too hard. Doctors and scientists have attempted for decades to unlock what really happens inside fragile lungs.

"This unique lung-on-a-chip model opens new, preclinical pathways of discovery that will allow researchers to better understand the interplay of immune responses to severe viral infections and evaluate critical antiviral treatments,” said Roy.

For Singh, the Carl Ring Family Professor in the George W. Woodruff School of Mechanical Engineering with a joint appointment in the Wallace H. Coulter Department of Biomedical Engineering, this research is deeply personal. He lost an uncle when an infection overwhelmed his cancer-weakened immune system.

“That experience stays with you,” Singh reflected. “It made me want to build systems that could predict and prevent outcomes like that, so fewer families go through what mine did. I think about my uncle all the time. If work like this means fewer families lose someone they love, then it’s worth everything.”

That motivation pushed his team to reimagine what a lung-on-a-chip could do, setting the stage for the breakthroughs that followed.
 

When the Lung Fought Back

The turning point came when Roy’s and Singh’s team peered through a microscope and saw something no one had ever witnessed on a chip: blood and immune cells coursing through tiny vessel-like structures, behaving just as they do in a living lung.

For years, researchers had struggled to add immunity to organ-on-a-chip systems. Immune cells often died quickly or failed to circulate and interact with tissue the way they do in people. the team solved that problem, creating a chip where immune cells could survive and coordinate a defense.

“It was an amazing breakthrough moment,” Singh said.

The true test came when the team introduced a severe influenza virus infection. The lung mounted an immune response that closely mirrored what doctors see in patients. Immune cells rushed to the site of infection, inflammation spread through tissue, and defenses activated in response.

“That was when we realized this wasn’t just a model,” Singh said. “It was capturing the real biology of disease.”

Singh and Roy’s research is published in the journal Nature Biomedical Engineering.
 

A More Human Approach

For decades, lung research has relied on animal models. But mice don’t get asthma like children. Their bodies don’t mount the same defenses.

“Five mice in a cage may respond the same way, but five humans won’t,” Singh explained. “Our chip can reflect that difference. That’s what makes it more accurate, and why it could dramatically reduce the need for animal models.”

Krish Roy emphasized its potential.

“The Food and Drug Administration’s strategic vision on reducing animal testing and developing predictive non-animal models aligns perfectly with our work. This device goes further than ever before in modeling human severe influenza and providing unprecedented insights into the complex lung immune response,” he said.


Fighting More Than the Flu

What began with influenza now expands to a wider range of diseases. Roy and Singh believes the platform can be used to study asthma, cystic fibrosis, lung cancer, and tuberculosis. The researchers are also working to integrate immune organs, showing how the lung coordinates with the body’s defenses.

The long-term vision is personalized medicine: chips built from a patient’s own cells to predict which therapy will work best. Scaling, clinical validation, and regulatory approval will take years, but Singh is undeterred.

“Imagine knowing which treatment will help you before you ever take it,” Singh said. “That’s where we’re headed.”

Where we’re headed, the future doesn’t wait for illness. Instead, it anticipates it, intercepts it, and rewrites the outcome.

 

Georgia Tech postdoctoral researcher Rachel Ringquist was the first author leading the study.

This research was supported by Wellcome Leap, with additional funding from the National Institutes of Health, Carl Ring Family Endowment, and the Marcus Foundation.


Ringquist, R., Bhatia, E., Chatterjee, P. et al. An immune-competent lung-on-a-chip for modelling the human severe influenza infection response. Nature Biomedical Engineering, September 2025 Vol.9 No.9

DOI: https://doi.org/10.1038/s41551-025-01491-9

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Michelle Azriel Sr. Writer-Editor

Sep. 22, 2025
James Stroud examines a lizard in the field. (Credit: Day’s Edge Productions)

James Stroud examines a lizard in the field. (Credit: Day’s Edge Productions)

James Stroud catching lizards in the field. (Day’s Edge Productions)

James Stroud catching lizards in the field. (Day’s Edge Productions)

Georgia Tech’s James Stroud has been awarded a 2025 Maxwell/Hanrahan Award in Field Biology. Presented by the Maxwell/Hanrahan Foundation, the award recognizes outstanding scientists conducting field research that both explores the natural world and leverages collaboration. 

An assistant professor in the School of Biological Sciences, Stroud is one of just five scientists selected to receive this year’s honor, which includes $100,000 of funding to support his work.

“I’m honored to receive this award,” he says. “This support affirms the value of field-based research, and underscores the importance of collaborative, long-term field studies.”

From ecology to empowerment

An evolutionary biologist, Stroud uses lizards to explore how ecological and evolutionary processes at the micro scale may underlie broader patterns of biological diversity at a larger scale — research that involves both computational analysis and long-term field studies.

“My lab’s research focuses on studying lizards in their natural habitats, allowing us to directly investigate how species adapt and evolve in real time,” he shares. “This helps us understand how these ecological and evolutionary processes shape life on Earth."

In South Florida, Stroud’s fieldwork focuses on ‘Lizard Island’ — a football field-sized island with a 1,000-lizard population. Operating for a decade, it is one of the world’s longest-running active evolutionary studies of its kind. This year, Stroud published research documenting evolution in action on the island when two species met for the first time, providing some of the clearest evidence to date of evolution in real-time. 

Outside of field research, Stroud recently led a Nature review paper providing the first-ever comprehensive analysis of long-term evolutionary studies, underscoring the critical need for these types of studies. 

Stroud has also developed a community science project called “Lizards on the Loose.” A collaboration with Fairchild Tropical Botanic Garden, the program engages middle school students from more than 100 schools across South Florida through the iNaturalist online platform and mobile app. Together, they have recorded thousands of lizard observations in their school grounds, local parks, and back yards.

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Written by Selena Langner

Sep. 18, 2025
Hong Yeo holds shoe insert.

Hong Yeo holds the wearable electronic device made of more than 170 thin, flexible sensors that measure foot pressure — a key metric for determining whether someone is off-balance. [Photos by Joya Chapman]

Shoe insert

The wearable electronic device, developed by Georgia Tech researchers, is made of more than 170 thin, flexible sensors that measure foot pressure — a key metric for determining whether someone is off-balance.

Maintaining balance while walking may seem automatic — until suddenly it isn’t. Gait impairment, or difficulty with walking, is a major liability for stroke and Parkinson’s patients.  Not only do gait issues slow a person down, but they are also one of the top causes of falls. And solutions are often limited to time-intensive and costly physical therapy.

A new wearable electronic device that can be inserted inside any shoe may be able to address this challenge. The device, developed by Georgia Tech researchers, is made of more than 170 thin, flexible sensors that measure foot pressure — a key metric for determining whether someone is off-balance. The sensor collects pressure data, which the researchers could eventually use to predict which changes lead to falls.

The researchers presented their work in the paper, “Flexible Smart Insole and Plantar Pressure Monitoring Using Screen-Printed Nanomaterials and Piezoresistive Sensors.” It was the cover paper in the August edition of ACSApplied Materials & Interfaces

Pressure Points

Smart footwear isn’t new — but making it both functional and affordable has been nearly impossible. W. Hong Yeo’s lab has made its reputation on creating malleable medical devices. The researchers rely on the common commercial practice of screen-printing electronics to screen-print sensors. They realized they could apply this printing technique to address walking difficulties.

“Screen-printing is advantageous for developing medical devices because it's low-cost and scalable,” said Yeo, the Peterson Professor and Harris Saunders Jr. Professor in the George W. Woodruff School of Mechanical Engineering. “So, when it comes to thinking about commercialization and mass production, screen-printing is a really good platform because it's already been used in the electronics industry.”

Making the device accessible to the everyday user was paramount for Yeo’s team. A key innovation was making sure the wearable is thin enough to be comfortable for the wearer and easy to integrate with other assistive technologies. The device uses Bluetooth, enabling a smartphone to collect data and offer the future possibility of integrating with existing health monitoring applications.

Possibilities for real-world adaptation are promising, thanks to these innovations. Lightweight and small, the wearable could be paired with robotics devices to help stroke and Parkinson’s patients and the elderly walk. The high number of sensors could make it easier for researchers to apply a machine learning algorithm that could predict falls. The device could even enable professional athletes to analyze their performance.

Regardless of how the device is used, Yeo intends to keep its cost under $100. So far, with funding from the National Science Foundation, the researchers have tested the device on healthy subjects. They hope to expand the study to people with gait impairments and, eventually, make the device commercially available. 

“I'm trying to bridge the gap between the lack of available devices in hospitals or medical practices and the lab-scale devices,” Yeo said. “We want these devices to be ready now — not in 10 years.”

With its low-cost, wireless design and potential for real-time feedback, this smart insole could transform how we monitor and manage walking difficulties — not just in clinical settings, but in everyday life. 

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Tess Malone, Senior Research Writer/Editor

tess.malone@gatech.edu

Sep. 18, 2025
Default Image: Research at Georgia Tech

Georgia Tech's AI-fueled exoskeleton adapts to every step, helping patients relearn to walk with less effort and more confidence.Traditional robotic exoskeleton models require extensive manual calibration, but Aaron Young, associate professor in the George W. Woodruff School of Mechanical Engineering, and his team developed AI-driven software that automatically adapts to each user’s gait. By using a neural network, the system continuously monitors and adjusts support with each step, gradually syncing with the wearer’s unique movement. In this study, the team used a hip exoskeleton that delivers torque at the hip joint to help stroke survivors walk more easily.

Crossing a room shouldn’t feel like a marathon. But for many stroke survivors, even the smallest number of steps carries enormous weight. Each movement becomes a reminder of lost coordination, muscle weakness, and physical vulnerability.

A team of Georgia Tech researchers wanted to ease that struggle, and robotic exoskeletons offered a promising path. Their findings point to a simple but powerful shift: exoskeletons that adapt to people, rather than forcing people to adapt to the machine. Using artificial intelligence (AI) to learn the rhythm of patients’ strides in real time, the team showed how these devices can reduce strain and increase efficiency. They also demonstrated how the technology can help restore confidence for stroke survivors. 

The Robot Finds the Rhythm

A robotic exoskeleton is a wearable device that helps people move with mechanical support. Traditional exoskeletons require endless manual adjustments — turning knobs, calibrating settings, and tweaking controls. 

“It can be frustrating, even nearly impossible, to get it right for each person,” said Aaron Young, associate professor in the George W. Woodruff School of Mechanical Engineering. “With AI, the exoskeleton figures out the mapping itself. It learns the timing of someone’s gait through a neural network, without an engineer needing to hand-tune everything.”

The software monitors each step, instantly updates, and fine-tunes the support it provides. Over time, the exoskeleton aligns its movements with the unique gait of the person wearing it. In this study, the research team used a hip exoskeleton, which provides torque at the hip joint — in other words, adding power to help stroke survivors walk or move their legs more easily.
 

Taking Smarter Steps

Walking after a stroke can be tough and unpredictable. A patient’s stride can change from one day to the next, and even from one step to the next. Most exoskeletons aren’t built for that kind of variation. They are designed around the steady, even gait of healthy young adults, which can leave stroke survivors feeling more unsteady than supported.

Young’s breakthrough, detailed in IEEE Transactions on Robotics, is a neural network — a type of AI that learns patterns much like the human brain does. Sensors at the hip pick up how someone is moving, and the network translates those signals into just the right boost of power to support each step. It quickly figures out a person’s unique walking pattern. But lead clinician Kinsey Herrin said the AI’s learning doesn’t stop there. It keeps adjusting as the patient walks, so the exoskeleton can stay in sync even during stride shifts.

“The speed really surprised us,” Young said. “In just one to two minutes of walking, the system had already learned a person’s gait pattern with high accuracy. That’s a big deal, to adapt that quickly and then keep adapting as they move.”

Tests showed the system was far more accurate than the standard exoskeleton. It reduced errors in tracking stroke patients’ walking patterns by 70%.

Young emphasized that this research is about more than metrics. “When you see someone able to walk farther without becoming exhausted, that’s when you realize this isn’t just about robotics — it’s about giving people back a measure of independence,” he said.
 

Adapting Anywhere

Every exoskeleton comes with its own set of sensors, so the data they collect can look completely different from one device to the next. A neural network trained on one machine often stumbles when it’s moved to another. To get around that, Young’s team designed software that works like a universal adapter plug — no matter what device it’s connected to, it converts the signals into a form the AI can use. After just 10 strides of calibration, the system cut error rates by more than 75%.

“The goal is that someone could strap on a device, and, within a minute, it feels like it was built just for them,” Young said.


A Step Toward the Future

While the study centered on stroke survivors, the implications are far broader. The same adaptive approach could support older adults coping with age-related muscle weakness, people with conditions like Parkinson’s or osteoarthritis, or even children with neurological disabilities. 
Young and his team are now running clinical trials to measure how well the AI-powered exoskeleton supports people in a wide range of everyday activities.

“There’s no such thing as an ‘average’ user,” Young said. “The real challenge is designing technology that can adapt to the full spectrum of human mobility.”

If Georgia Tech’s exoskeleton can rise to that challenge, the promise goes well beyond the lab. It could mean a world where technology doesn’t just help people walk — it learns to walk with them.

Inseung Kang, who holds a B.S., M.S., and Ph.D. from Georgia Tech, is the paper’s lead author and now an assistant professor of mechanical engineering at Carnegie Mellon University. He explained that the real promise is in what comes next. 

“We’ve developed a system that can adjust to a person’s walking style in just minutes. But the potential is even greater. Imagine an exoskeleton that keeps learning with you over your lifetime, adjusting as your body and mobility change. Think of it as a robot companion that understands how you walk and gives you the right assistance every step of the way.”

 

Aaron Young is affiliated with Georgia Tech’s Institute for Robotics and Intelligent Machines.

This research was primarily funded by a grant (DP2HD111709-01) from the National Institutes of Health New Innovator Award Program. Georgia Tech researchers have created the first lung-on-a-chip with a functioning immune system, allowing it to respond to infections much like a real human lung. The breakthrough, published in Nature Biomedical Engineering, provides a more accurate way to study diseases, test therapies, and reduce reliance on animal models. With potential applications in conditions from influenza to cancer, the technology opens the door to personalized medicine that predicts how individual patients will respond to treatment.

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Michelle Azriel Sr. Writer - Editor

Sep. 16, 2025
ATP synthase is an enzyme that has been using phosphate to generate life’s energy for millions of years.

ATP synthase is an enzyme that has been using phosphate to generate life’s energy for millions of years. Nanoclustering/Science Photo Library via Getty Images

The questions of how humankind came to be, and whether we are alone in the universe, have captured imaginations for millennia. But to answer these questions, scientists must first understand life itself and how it could have arisen.

In our work as evolutionary biochemists and protein historians, these core questions form the foundation of our research programs. To study life’s history billions of years ago, we often use clues called molecular “fossils” – ancient structures shared by all living organisms.

Recently, we discovered that an important molecular fossil found in an ancient protein family may not be what it seems. The dilemma centers, in part, on a simple question: What does it mean if a simple molecular structure – the fossil – is found in every single organism on Earth? Do molecular fossils point to the seeds that gave rise to modern biological complexity, or are they simply the stubborn pieces that have resisted erosion over time? The answers have far-reaching implications for how scientists understand the origins of biology.

Follow the Phosphorus to Follow Life

Life is made of many different building blocks, one of the most important of which is the chemical element phosphorus. Phosphorus makes up part of your genetic material, powers complex metabolic reactions and acts as a molecular switch to control enzymes.

Phosphorus compounds – specifically a charged form called phosphate – have a number of unique chemical properties that other biological compounds cannot match. In the words of the pioneering organic chemist F.H. Westheimer, they are chemically able to “do almost everything.”

Their unique combination of stability, versatility and adaptability is why many researchers argue that following phosphorus is key to finding life. The presence of phosphorus both close to home – in the ocean or on one of Saturn’s moons – and in the farthest reaches of our galaxy is strong evidence for the potential for life beyond Earth.

Chemical structure of a nucleotide, made of a phosphate, ribose sugar and base

Phosphate is part of many essential biological molecules, including the building blocks of DNA. Charles Molnar and Jane Gair, CC BY-SA

If phosphorus is so critical to life, how did early biology predating cells first use it?

Today, biological organisms are able to make use of phosphates through proteins – molecular machines that regulate all aspects of life. By binding to proteins, phosphates regulate metabolism and cellular communication, and they serve as a source of cellular energy.

Further, the process of phosphorylation, or adding a phosphate group to a protein, is ubiquitous in biology and allows proteins to perform functions their individual building blocks cannot. Without proteins, the existence of organisms such as bacteria and humans may not be possible.

Given how essential phosphorus is to life, scientists hypothesize that phosphate binding was among the first biological functions to emerge on Earth. In fact, current evidence suggests that the first phosphate-binding proteins are truly ancient – even older than the last universal common ancestor, the hypothetical mother cell to all life on Earth that existed around 4 billion years ago.

A Mysterious Phosphate-Binding Fossil

One family of phosphate-binding proteins, called P-loop NTPases, regulates everything from the communication between cells to the storage of energy and are found across the tree of life. Because P-loop NTPases are among the most ancient protein families, analyzing their properties can provide key insights into both the emergence of proteins and how primitive life used phosphates.

Although P-loop NTPases are diverse in structure, they share a common motif called a P-loop. This component binds to phosphate by wrapping a nest of amino acids – the building blocks that make up proteins – around the molecule. Every known organism has multiple families of P-loop NTPase, which makes the P-loop an excellent example of a molecular fossil that can provide clues about the evolution of life. Our crude analysis of the human genome estimates that humans have about 5,000 copies of P-loops.

When part of a larger protein structure, the P-loop folds like origami into a shape that is ideal for hugging a phosphate molecule. These nests are extremely similar to each other, even when the surrounding proteins are only distantly related in function. A landmark study in 2012 argued that even if the P-loop nest is extracted from a protein, it can still bind to phosphate. In other words, the ability of a P-loop to form a nest is determined by its interactions with phosphate, not its protein scaffold.

This study provided the first evidence that some forms of the P-loop sequence could have functioned billions of years ago, even before the emergence of large, complex proteins. If true, this implies that P-loop nests may have seeded the emergence and evolution of many of the phosphate-binding proteins seen today.

Interrogating the History of the P-loop

The pioneer of bioinformatics, Margaret Oakley Dayhoff, hypothesized in 1966 that the large collection of big proteins seen today arose from small peptides that were duplicated and fused over long periods of time. Although P-loops may have evolved in a different way, Dayhoff’s realization was the first to clarify how complex forms could have arisen from much simpler ones.

Inspired by Dayhoff’s hypothesis, we sought to interrogate the role that simple P-loops may have played in the evolution of the complex proteins key to life. Our findings challenge what’s currently known about these molecular fossils.

Diagram showing the evolution of amino acids to oligopeptides to complex proteins

The Dayhoff hypothesis proposed that large, complex proteins arose from the duplication and merging of smaller, simpler peptides over time. Merski et al./Biomolecules, CC BY-SA

Using computer models, we compared a range of P-loops from the P-loop NTPase family to a control group made of the same amino acids but in a different order. While these control loops are also found in proteins, they do not form nests.

Although the P-loops and the control loops are very different in their nest-forming ability, we found that they both are able to form transient nests when embedded in proteins. This meant that, contrary to popular belief, the amino acid sequence of P-loops aren’t special in their ability to form nests – as would be expected if they alone were the seeds for many modern proteins.

A Fossil Eroded Over Time

Our work strongly suggests that while the P-loop is a molecular fossil, the true nature of its form billions of years ago may have been eroded by the sands of time.

For example, when we repeated our simulations in a different solvent – specifically methanol – we found that P-loops situated in their parent proteins were able to regain some of their ability to form nests. This doesn’t mean that being in methanol drove the first proteins with P-loops to form the nests critical for life. But it does emphasize the importance of considering the surrounding environment when studying peptides and proteins.

Just as archaeologists know to be careful in how they interpret physical fossils, historians of protein evolution could take similar care in their interpretation of molecular fossils. Our results complicate the current understanding of early protein evolution and, consequently, some aspects of the origins of life.

In resetting the field’s broader understanding of how these crucial proteins emerged, scientists are poised to start rewriting our own evolutionary history on this planet.The Conversation

 

This article is republished from The Conversation under a Creative Commons license. Read the original article.

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Authors:

Caroline Lynn Kamerlin, professor of chemistry and biochemistry, Georgia Institute of Technology 

Liam Longo, specially appointed associate professor, Earth-Life Science Institute, Institute of Science Tokyo

Media Contact:

Shelley Wunder-Smith
shelley.wunder-smith@research.gatech.edu

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