Professor Emeritus Phil Sparling's newspaper columns are now a book of essays

May 7, 2018 | Atlanta, GA

By Mallory Rosten, Student Communications Assistant, College of Sciences

School of Biological Sciences Professor Emeritus Phillip Sparling has published his first book of creative nonfiction. “The Sneakers in the Closet and Other Essays” explores the intersection of sports, health, and life. It’s a collection of 24 stories (and a few poems), compiled and re-edited, from newspaper columns Sparling wrote over several years.

In the eponymous first essay, Sparling reminisces on a childhood full of sports and physical activity. As a kid, he was constantly on the move, taking detours from bicycling  to school to climb trees or scale a wall. He can measure the phases of his youth by sports: four square and kickball in elementary school; neighborhood pickup games of football, basketball, and baseball through junior high school; and then cross-country and track in high school. .

Maybe that’s why Sparling dedicated his research to unraveling connections between fitness and health. His early research focused on investigating relationships among endurance training, resistance training, energy balance, body composition, and cardiovascular health. In the mid-1990s, his research shifted to understanding physical activity and eating patterns as modifiable health behaviors.

Sparling joined Georgia Tech in 1979 as an assistant professor in what was then the Department of Physical Education. When he retired almost 30 years later, it had become the School of Applied Physiology, which merged with the School of Biology to form the School of Biological Sciences in summer 2016. During his last decade at Tech, Sparling taught a large lecture “Personal Health” course and the graduate-level courses “Exercise Physiology” and “Physical Activity and Health.”

In retirement, Sparling broadened his writing to include narrative nonfiction.  “It allows more creativity than scientific and technical writing,” Sparling says. He began publishing essays in Smoke Signals, the local paper of Big Canoe, a mountain community about one hour north of Atlanta. His editor and friends encouraged him to publish the essays in a book. In “The Sneakers in the Closet and Other Essays,” he reflects on various topics – from play, exercise, and fitness to diet, drugs, and doctors.

“My aim is to engage and educate by sharing stories, including personal reflections on growing up, finding a career and growing older,” Sparling says, “and to show how role models shape our health and well-being.” He hopes that people who read his stories walk away “better informed, empowered, and thankful.”

The book’s proceeds go to the Richard Gay Israel Health and Exercise Science Scholarship at Colorado State University.  Sparling describes his late colleague, Richard Gay Israel, as “salt-of-the-earth and a natural leader.”

At Georgia Tech, Sparling expanded the study of health and exercise by establishing and directing the Exercise Physiology Laboratory, developing the Ph.D. program in applied physiology, and advocating for the integration of behavioral science with biomedical science. For a decade, he served as chair of Georgia Tech’s Institutional Review Board for the protection of human subjects in research.

Sparling also had sabbatical experiences as a senior scientist with the Centers for Disease Control and Prevention and a Fulbright Scholar at University of Cape Town Medical School, in South Africa. In addition, Sparling was a leader in professional societies, including the American College of Sports Medicine and the Society of Behavioral Medicine.

 “I'm proud to have spent my career at Georgia Tech – a top-notch institution with excellent students, staff, and faculty,” Sparling says.

In addition to writing and reading, Sparling gardens and hikes with his wife, Phyllis, in the Georgia foothills where they live. They enjoy travel at home and abroad. And he continues to write columns to nudge folks to healthier ways and a fuller life.

For More Information Contact

A. Maureen Rouhi, Ph.D.
Director of Communications
College of Sciences

For the first time, scientists determine the reach of quorum sensing in an infection

May 31, 2018 | Atlanta, GA

“A large part of my research is thinking about how bacteria communicate,” says Sophie Darch. The postdoctoral researcher works with School of Biological Sciences Professor Marvin Whiteley, studying the social lives of bacteria.

Darch observes the conversations of bacteria, which take place via molecules they release into the environment and are sensed by other bacteria. In Darch’s experiments, completed messages are marked by the red-to-green change in the color of the bacterium sensing the molecule.

By sending and receiving extracellular signals, bacteria sense their neighbors. When enough bacteria are in the conversation, things happen. Sometimes it leads to changes in virulence or ability to establish an infection. The phenomenon is called quorum sensing.

Yet little is known about how quorum sensing proceeds during infection “Much of what is known about quorum sensing,” Darch says, “comes from studies of large populations of bacteria in an environment that does not compare with the natural infection site.” In infections, for example, bacteria are often found in small, dense clusters, called aggregates. “It’s really important for us as scientists to think about what bacterial growth looks like in an infection,” Darch says.

In a paper in the Proceedings of the National Academy of Sciences USA, Darch, Whiteley, and colleagues describe for the first time how close bacteria need to be to “talk” with each other in an environment similar to an infection. Their findings could reveal new ways to disrupt bacterial signaling and provide other targets to treat infections.

The work was supported by the National Institutes of Health, the Cystic Fibrosis Foundation, Human Frontiers Science, and the Welch Foundation.

Cystic Fibrosis Model

The study uses an environment similar to the chronic infection of the cystic fibrosis (CF) lung.

CF is a genetic disease that causes buildup of sticky mucus in the lung. The viscous setting CF creates makes the organ prime real estate for disease-causing bacteria. Among the most prevalent of these in the CF lung is Pseudomonas aeruginosa.

P. aeruginosa infections pose a huge problem because they are resistant to many antibiotics and are difficult to treat. Often P. aeruginosa infection is what causes death among patients with CF.

The team used a synthetic CF sputum media (SCFM2), based on the makeup of lung secretions from patients. In nutritional content and physical form, the medium is similar to sputum from the lung. Importantly, P. aeruginosa forms aggregates in SCFM2 that are similar in size to those observed in CF lung tissue.

3-D Printed Bacteria

To begin to answer the question “How close do you have to be to talk to your neighbor?” the team collaborated with Jason Shear at the University of Texas, Austin. The Shear Lab had developed a micro-3D-printing platform that could be used to engineer the growth of bacteria to mimic infections.

Bacteria are not uniformly distributed in infections. “Instead we see bacterial aggregates that vary in size and can be separated by large distances,” Whiteley says. “We needed an experimental method to engineer these types of infection landscapes in the lab.”

Using Shear’s micro-3D-printing platform, the team printed bacterial aggregates of exact positions and sizes.

A typical experiment starts by enclosing one producer cell in a picoliter-sized trap, using micro-3D-printing. After multiple cell divisions, the population fills the volume of the trap. Then SCFM2-containing aggregates of responder cells are overlaid the porous trap.

They observe the one-way flow of signals from aggregates in a trap (producers) to aggregates outside receiving signals (responders). They could see the response of completed conversations by responders changing color from red to green.

Implications for Cystic Fibrosis

“We found that bacterial aggregates slightly larger than those in CF lung – containing about 2,000 cells – were not large enough to signal to other aggregates,” Darch says.

Prior to this study, it was thought that bacterial signaling could occur over extended distances. However, in the CF lung, small populations of bacteria are scattered across a large volume and separated by large distances. Aggregates are unlikely to “talk” to each other. 

It took aggregates containing at least 5,000 cells to successfully send signals to neighbors as far away as 176 micrometers. “These aggregates are around five times the size of the average aggregate observed in CF lung tissue” Darch says “From these data, communication is likely confined within an individual aggregate rather than being a population-wide phenomenon”.

Among CF patients who are at least 20 years old, 80% are infected with P. aeruginosa. “Infection with P. aeruginosa remains a significant clinical problem in immunocompromised patients, particularly those with CF,” Darch says. “Understanding better how bacteria communicate has the potential to find ways of disrupting the communication and potentially diminishing bacterial virulence.”

“The study provides benchmark data for how quorum sensing might proceed in an environment similar to the CF lung,” says Whiteley, who is a member of the Parker H. Petit Institute for Bioengineering and Bioscience. “In different settings, where P. aeruginosa and other bacteria exist as aggregates of different sizes, communication may look different. Future studies will involve experimental and modeling work to further examine the spatial parameters of quorum sensing in CF and other infections, such as a chronic wound.”

Figure Caption

(Left) Rendered confocal laser-scanning micrograph of a micro-3D-printed trap (red)  surrounded by P. aeruginosa aggregates responding to quorum-sensing signals (green) in a synthetic CF sputum media (SCFM2).

(Right) Rendered confocal laser-scanning micrograph of responding (green) and non-responding (red) P. aeruginosa aggregates formed in a synthetic CF sputum media (SCFM2).

For More Information Contact

A. Maureen Rouhi, Ph.D.
Director of Communications
College of Sciences

With Ford Foundation support, Kennda Lynch seeks to learn more about microbes that consume rocket fuel as energy source

June 19, 2018 | Atlanta, GA

Liquid water on Mars fired everyone’s fancy in 2015. Water on Mars today exists in the form of hydrated perchlorates, said the researchers who led the work. They include James Wray, an associate professor in the School of Earth and Atmospheric Sciences (EAS).

The finding boosts the possibility of life on the red planet. Water tied to perchlorate meets life’s two needs: water and energy. Perchlorate emits huge amounts of energy when it reacts. For this reason, its salts are ingredients of rocket boosters and fireworks.

Perchlorate as Food for Microbes

Some organisms use perchlorate as an energy source. So-called perchlorate-reducing microorganisms (PRM) would likely live in places where perchlorate naturally occurs. Yet coexistence of PRMs with naturally occurring perchlorate has not been detected until recently.

One likely place where such coexistence may occur is Pilot Valley, in the Great Salt Lake Desert of Utah. Pilot Valley is a hypersaline, perchlorate-rich, and closed basin. It loses water mainly from evaporation.

Yet perchlorate vanishes from Pilot Valley to an extent that cannot be explained by water loss, says Kennda Lynch. She’s a postdoctoral researcher working with Wray and School of Biological Sciences Professor Frank Rosenzweig.

Perchlorate is soluble in water, but it will not evaporate with water. Perchlorate salt residues should accumulate as water evaporates. Yet Pilot Valley shows a decline of such salt remains. The perchlorate is just disappearing.  

Lynch believes PRMs in Pilot Valley must be using the perchlorate. While doing her Ph.D., Lynch found the first known coexistence of PRMs and naturally occurring perchlorate in Pilot Valley. Because no one knows what these PRMs are, Lynch will spend the next year finding out. Supporting her work is a recently announced Ford Foundation fellowship.

Ford Foundation Fellowship

“I’m extremely honored to be a Ford Fellow,” Lynch says. “This funding will allow me to continue this important research, which will aid the search for evidence of life on other planets.”

Ford Foundation Fellowship Programs seek to increase diversity in academia by increasing ethnic and racial diversity. As a fellow, Lynch will gain access to one of the largest communities of academic professionals committed to creating and fostering diverse environments in higher education.

The fellowship presents a “unique opportunity to forge connections with extraordinary individuals as I continue efforts to broaden diversity within the field of astrobiology,” she says.

Lynch’s Ford Foundation research aims to find out what microbial communities use perchlorate. What are the mechanisms at their disposal?

Lynch will examine whether active perchlorate metabolism takes place in Pilot Valley. If so, what other metabolic processes occur when that process is on?

Then she will use the findings to help define a model for perchlorate-driven life on Mars. 

Filling the Knowledge Gap

The work will help NASA’s Mars Exploration Program understand the extent of habitable environments on Mars, including energy sources that could drive microbial systems. “Perchlorate is one of the most abundant and most energetic metabolic resources on Mars,” Lynch says. Yet basic questions abound about its use to support life in a place that looks like Mars.

Working in Pilot Valley – an Earth stand-in for Mars – Lynch aims to fill the knowledge gap. She will run experiments to detect perchlorate use. She will apply state-of-the-art techniques to find genes for, and expression of, perchlorate metabolism. She will also isolate PRMs. 

Lynch will continue to work with Wray and Rosenzweig. However, she will be based mostly in the lab of EAS Assistant Professor Jennifer Glass.

“My lab members and I are very excited to have Kennda join us,” Glass says. “Kennda will bring a new perspective on Mars’s relevance to our group. Serendipitously, we have cultivated microbes similar to PRMs in our recent studies, and we look forward to helping Kennda grow new, exciting microbes from Pilot Valley.”

For More Information Contact

A. Maureen Rouhi, Ph.D.
Director of Communications
College of Sciences

Dehydration can impair your ability to think clearly, a new study suggests. Researchers found that athletes who lost fluid equal to 2% their weight took a hit to their cognition. Even this mild to moderate level of dehydration - the loss of 2 pounds for someone who weighs 100 pounds and four pounds for someone weighing 200 - led to attention problems and impaired decision making, according to the report in Medicine & Science in Sports & Exercise.  In particular, dehydration led to impairment in tasks requiring attention, motor coordination, and so-called executive function, which includes things like map recognition, grammatical reasoning, mental math, and proofreading, for example. “We’ve known that physical performance suffers at a threshold of 2% of body mass, particularly when it’s from exercise in a warm environment,” said study coauthor Mindy Millard-Stafford, a professor in the School of Biological Sciences and director of the physiology lab at the Georgia Institute of Technology.


The School of Biological SciencesMindy Millard-Stafford's simple explanation for brain fog continues to garner attention. Spoiler alert: it's staying hydrated. For more insight on the cognitive price we pay for dehydration, read Georgia Tech's take here

It's an unfortunate fact of life that as we get older, our cells gradually lose the ability to heal themselves. Thankfully, one part of that might be treatable in the near future. Young Jang of the School of Biological Sciences and researchers have developed a hydrogel that holds muscle stem cells.The team says this could treat injuries in the elderly and people with muscular dystrophy. Read the Georgia Tech coverage of the study here and coverage by BioSpace.

About the Speaker
Valerie J. Paul is the Director of the Smithsonian Marine Station at Fort Pierce and the Head Scientist of the Chemical Ecology Program. She researches marine chemical ecology, marine plant and herbivore interactions, coral reef ecology, and the ecological roles of marine natural products. In her coral reef ecology research, she studies the impact of cyanobacterial bloom on coral reefs and larvae of reef building corals. She has been a fellow of the American Association for the Advancement of Science since 1996, and was the chairperson of the Marine Natural Products Gordon Research Conference in 2000.

Event Details


A long time ago, in a city far, far away, a mathematician solved a puzzle, the solution of which made our modern, connected world possible. Georgia Tech's School of Music and School of Mathematics have teamed up with local Atlanta artists to create a performance combining contemporary dance, original music, and storytelling. Called The Seven  Bridges of Königsberg, the concert celebrates this history and aims to spark people’s curiosity and convey the wonder of mathematics.

The classic puzzle that inspired Leonhard Euler to found the fields of topology and graph theory (or network theory) asked the simple question: Is it possible to cross all of the seven bridges of the city of Königsberg exactly once, with no repetition or backtracking? 

Euler was not content with a yes-or-no answer. Instead he began to think about the nature of connectedness in a mathematical way, as it applies to all possible cities with any number of islands and bridges; as well as to networks of transportation, commerce, and communication; to the pathways by which diseases or ideas spread; and ultimately to our contemporary interconnected life.

The Seven Bridges of Königsberg was selected by a new program called Science in Vivo, funded by the Simons Foundation, to receive one of its inaugural 10 awards as an Experimental Site “exploring what is possible when science experiences for the public are integrated into existing cultural gatherings.” 

The debut performance on Sept. 13, 2018 will take place on the Georgia Tech campus along Atlantic Ave, where an installation of the Seven Bridges of Königsberg puzzle was constructed earlier this year.   

To tell about the foundation of graph theory, the Georgia Tech Symphony Orchestra will perform a new composition by composer Marshall Coats, while a math team and dancers interpret the story and some concepts about graphs, as choreographed by guest artist Kristel Tedesco.

This performance will be repeated at the Bailey Center in the Kennesaw State University on Sept. 23, 2018. Other versions of the show will take place at public locations around Atlanta and the Southeast region in September and October.

In addition to the spectacle, the audience will have opportunities to explore mathematical puzzles and games and to personally engage with the mathematicians and artists.

The Seven Bridges of Königsberg is a production of Mathematics in Motion, Inc. and the Georgia Tech Schools of Music and Mathematics, with financial support from the Georgia Tech College of Design, the Georgia Tech College of Sciences, the Georgia Tech Office of the Arts as one of the Creative Curriculum Initiatives, and Science in Vivo.

Event Schedule

11:00 AM Interactive exposition by Club Math

12:15 PM Remarks by School of Mathematics Chair and College of Design Dean Steven French 

12:20 PM Music and Dance Performance 

1:00 PM Interactive engagement with Club Math

Directions to Seven Bridges Plaza 

The Seven Bridges Plaza is along the Atlantic Drive Promenade, right next to the Howey Physics Building. 

By Georgia Tech Trolley: Get off at the intersection of Ferst Drive and Atlantic Drive. Walk toward the Einstein Statue, The Seven Bridges Plaza will be on the right, past the Howie Building. You can catch the Georgia Tech Trolley at the MARTA Midtown station. 

By private transportation: 

If you are coming from south of Atlanta:

  1. Take I-85 North to 10th Street/14th Street/Ga Tech (Exit No. 150)
  2. Take a left onto 10th Street at the light at the end of the ramp
  3. Go straight through 3 traffic lights
  4. Take a left onto State Street (the next light)
  5. Go through one stop sign
  6. The Howey Physics Building is the first building on the left. A Visitor Parking Lot is in front of the Building. 

If you are driving from the east or west:

  1. Take I-20 into the city.
  2. Exit North onto I-75/85.
  3. Take I-75/85 North to the ramp of 10th Street/14th Street/Ga Tech.(Exit 150)
  4. Take a left onto 10th Street at the light at the end of the ramp.
  5. Go straight through 3 traffic lights.
  6. Take a left onto State Street (the next light).
  7. Go through one stop sign.
  8. The Howey Physics Building is the first building on the left. A Visitor Parking Lot is in front of the building.


Event Details


The NASA Astrobiology Institute marks its 20th anniversary this year and Georgia Tech is throwing a party! This celebration will feature talks and a poster session by faculty members, NASA Postdoctoral Program Fellows, graduate students, and postdoctoral researchers in Georgia Tech's vibrant astrobiology community.

The celebration is hosted by Frank Rosenzweig, professor of biological sciences and principal investigator of the NAI program Reliving the Past. 

The event is sponsored by the NASA Astrobiology Institute and the Georgia Tech College of Sciences, School of Chemistry and Biochemistry, School of Biological Sciences, and the Parker H. Petit Institute for Bioengineering and Bioscience. 

The event is by by invitation only.

Speakers, Morning Session starting at 8:30 AM

Thom Orlando, professor of chemistry and biochemistry
"An Overview of REVEALS and CSTAR Programs"

Amanda Stockton, assistant professor of chemistry and biochemistry
"High Impact Chemistry: The Icy Moons Penetrator Organic Analyzer"

Loren Williams, professor of chemistry and biochemistry
"Visualizing the Origins of Life in Biopolymers"

Nick Hud, professor of chemistry and biochemistry and principal investigator of the Center for Chemical Evolution (CCE)
"Some Highlights of CCE Discoveries on the Possible Origins and Early Evolution of Biopolymers"

Martha Grover, professor of chemical and biomolecular engineering
"Prebiotic Replication of an RNA Duplex Containing an Active Ribozyme"

Chris Reinhard, assistant professor of Earth and atmospheric sciences
"Climate and Atmospheric Biosignatures on Reducing Worlds"

Jeff Bowman for Britney Schmidt, assistant professor of Earth and atmospheric sciences
"Oceans Across Space and Time: A Multi-Institutional Effort to Understand and Identify Life in Extraterrestrial Oceans"

Jennifer Glass, assistant professor of Earth and atmospheric sciences
"Laughing Gas as a Precursor to Aerobic LIfe"

Will Ratcliff, assistant professor of biological sciences
"Solving Physical Challenges during the Origin of Multicellularity by Evolving Simple Development

James Wray, associate professor of Earth and atmospheric sciences
"Orbital Spectral Signatures of Changing Habitable Environments on Mars" 

Lunch and Poster Session, 12:30-1:45 PM
Speakers, Afternoon Session, starting at 2 PM

Pedram Samani, postdoctoral researcher, Georgia Tech
"Experimental Evolution of Anisogamy: An Inquiry into the Origins of Sexes"

Peter Conlin, NPP Fellow, Georgia Tech
"Experimental Evolution of Adaptive Phenotypic Plasticity in a Temporally Varying Environment"

Caroline Turner, NPP Fellow, University of Pittsburgh
"Environmental Similariy (Mostly) Predicts Genetic Similarity"

Nadia Szeinbaum, NPP Fellow, Georgia Tech
"A Microbial Ecology Perspective on the Success of Oxygenic Photosynthesis"

Moran Frankel-Pinter, NPP Fellow, Georgia Tech
"Dynamic Polymerization of Prebiotic Depsipeptides Allows Selection of Stable Structures"

Micah Schaible, NPP Fellow, Georgia Tech
"Ionizing Radiation Effects on the Surfaces of Airless Bodies"

Event Details


Andrew Spence, PhD
Department of Bioengineering
Temple University

How do animals use information from peripheral sense organs when they move? Long, distinguished scientific lineages have given insight into this question, both at the level of how these organs function, and how their input is integrated with more central nervous structures. Despite standing on the shoulders of these giants, interesting open questions remain; what is the relative contribution of different classes of sensory afferent to specific locomotor tasks? how is sensory feedback used as a function of phase? and to what extent can modulating sensory feedback be useful in treating neuromuscular disease or injury, and understanding mechanisms of recovery from injury? This talk will present ongoing work that seeks to use genetic tools to target and manipulate the activity of specific classes of sensory afferent in intact rodents. Early work using optogenetics in mice will be presented, followed by recent work using DREADDs to excite or inhibit large diameter afferents in rats. DREADDs are drug-activated, engineering receptors that allow remote activation or inhibition of neurons. Results of pilot work applying selective afferent modulation by DREADDs to both enhancement of the recovery from spinal cord injury, and to understanding the mechanisms underlying that recovery, in rats, suggest that this approach holds promise. Current limitations of genetic approaches will be discussed, and a risky foray into what may lie ahead will be presented.

About the Speaker
Andrew Spence is an applied physicist by training who leads a research group in animal locomotion. As a group, we are focused on how the nervous and mechanical systems work together to produce movement, taking an integrative approach that combines experimental work with mathematical modeling,  instrumentation, and some robotics. Andrew did his undergraduate work in physics at UC Berkeley, before doing a PhD in neuroscience and biomedical microdevices at Cornell University. He returned to Berkeley for a postdoc, and worked with Bob Full on the control of many-legged locomotion.

Before coming to Temple University, he was a faculty member in the Structure and Motion Laboratory at the Royal Veterinary College, London, working with Alan Wilson before becoming an independent researcher. Currently his group is focused on the role of constraints (stability, energetics) in shaping quadrupedal gait control, and in applying new neurogenetic techniques (chemogenetics in the form of DREADDs; optogenetics) to dissect the control of fast legged locomotion and to better treat spinal cord injuries.

Physiology Brownbag Seminars
The Physiology Group in the School of Biological Sciences hosts Brownbag Lunchtime Seminars twice a month on Wednesdays at noon in room 1253 of the Applied Physiology Building located at 555 14th Street NW, Atlanta, GA 30318. You are welcome to bring a lunch and join us as we ruminate with us on topics in Physiology! A full listing of seminars can be found at

Event Details



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