University of Mississippi Change Agents

Ever since humans put a man on the moon, we have dreamed of the next frontier: Mars. But while we may have the capacity to send rovers to explore the red planet, obstacles to human exploration persist, due to the length of the journey and unknowns about the toll it will take on the human body. In response to these questions and others, researchers at the University of Mississippi are investigating ideas that may make long-distance space travel more feasible.

Research by John Z. Kiss, dean of the University of Mississippi Graduate School, investigates how plants grow in space, information that could one day allow astronauts to generate food and oxygen during long-term missions.

A child of the 1960s, Kiss experienced the excitement of the moon landing, but he never expected he would one day work with NASA. After completing a Ph.D. in botany/plant physiology at Rutgers

University, Kiss accepted a postdoctoral fellowship working with NASA at the University of Colorado at Boulder. That relationship progressed into a series of collaborations that have stretched almost three decades and have included eight completed space flight projects and a ninth project under development. Seven of the eight completed projects have been collaborations with the European Space Agency.

Kiss served as the United States’ principal investigator on his most recently completed space project, Seedling Growth-2. In the experiment, plant seeds were delivered to the International Space

Station. After the seeds were watered in space and developed into young plants, photographs taken at the space station and downloaded to Earth allowed Kiss and his team to study the seedlings’ growth and development at different levels of gravity and in various light treatments. After their time at the International Space Station was completed, the seedlings were frozen at -80 degrees Celsius and returned to Earth, allowing Kiss and his team to study any changes in their genetic expression resulting from the altered conditions.

While plants and seeds have been studied at NASA since the beginning of space exploration, which has led to a basic understanding of their behavior in microgravity, or near zero gravity, Kiss and his team are also exploring how they respond to reduced gravity. Gravity on the moon and Mars are one-sixth and three-eighths of Earth’s gravity, respectively. Using the European Modular Cultivation System at the International Space Station, Kiss and his team have found that Mars’ level of gravity may be sufficient for normal plant growth, while the moon’s lower level of gravity creates anomalous plants.

The plant used by Kiss and his team is Arabidopsis thaliana, often considered the “lab rat” of plants. A flowering plant from the mustard family, it is ideal for study because its compact stature makes it easy to send to space and because its simple and thoroughly mapped genome is well-understood by scientists. In Seedling Growth-2, Kiss and his team sent 1,200 seeds to the International Space Station.

Kiss joined the UM faculty as dean of the graduate school in 2012. As dean, Kiss has continued his NASA research projects and shared research opportunities with students. He enjoys the opportunity to work with both undergraduate and graduate students in his lab.

“Research and graduate education are closely related,” Kiss said. “Continuing my research allows me to keep my finger on the pulse of research and keeps me in tune with students. I enjoy one-on-one mentorship, and it’s rewarding to see how students develop.”

In 2014, Kiss was awarded NASA’s Outstanding Public Leadership Medal, which recognizes nongovernment employees for notable leadership accomplishments that have significantly influenced the NASA mission.

“The award is a real honor,” Kiss said. “The legacy of NASA is public interest. Space exploration gets students interested in science and STEM careers. In this way, research is also an outreach opportunity. I am honored to be a part of that.”

Another UM scientist is studying the effects of reduced gravity and microgravity on an entirely different species: us. Just as reductions in gravity affect

seedling growth, these changes can also have mysterious – and often deleterious – effects on the human body. Richard Summers, associate vice chancellor for research at the UM Medical Center, has conducted groundbreaking research in the area on behalf of NASA’s Digital Astronaut Program, garnering national recognition.

From the earliest days of space exploration, NASA recognized health problems in astronauts returning from missions. Ostostatic hypotension, a form of low blood pressure that causes dizziness and fainting spells, was observed in as many as one-third of astronauts upon return. That problem was the first of many tackled by Summers, who uses computational modeling to better understand how space travel affects the human body.

“The barrier to go to Mars is the physiological barrier,” Summers said. “We know how to get a rocket up there. We just don’t know how to get people up there. If we are ever going to have a moon colony or Mars colony, we have to understand how people are going to come back.”

The concept of using a computer model to study the human body was an innovation pioneered by Dr. Arthur Guyton, a renowned physiologist whose career at the university and UM Medical Center spanned more than 40 years. While computer modeling had previously been used to study physics and chemistry, the concept of using modeling to better understand biological concepts was revolutionary. Summers worked under Guyton as a fellow and learned his method of computer modeling during clinical training. Summers’ publications in the area captured NASA’s interest.

To address the problem of ostostatic hypotension, Summers and his team studied astronauts immediately after they returned from missions and used modeling to better understand the physiological processes involved. They suggested a simple measure to prevent the complication: a pair of compression hose placed on the lower extremities during landing. The solution was also used during rescue measures in the 2010 Chilean Mining Incident, when the miners faced similar complications as they made their ascent to the earth’s surface from depths of more than 2,300 feet.

The University of Mississippi School of Law offers a certificate in Remote Sensing, Air and Space Law. This certificate provides a comprehensive understanding of the legal processes regulating domestic and international aerospace activities. Students enrolled in the certificate program receive distinctive, interdisciplinary knowledge and expertise.

Following his discovery about ostostatic hypotension, Summers continued to build models to study the body in space. For 10 years, he attended shuttle landings and performed tests on returning astronauts, including taking vitals, blood tests and echocardiographs. Although the space shuttle program was halted in 2011, Summers continues his research through a NASA Experimental Program to Stimulate Competitive Research, or EPSCoR, Research Award that explores cardiac changes in astronauts. Summers first discovered cardiac changes in astronauts while working with David Martin,

the ultrasound lead at the NASA Johnson Space Center Cardiovascular Laboratory in Houston, Texas, who received his bachelor’s and master’s degrees from UM. Summers and Martin noticed that echocardiograms performed at the International Space Station showed perplexing changes in heart structure. While in space, the astronauts’ hearts appeared to have changed shapes and locations. Through computational modeling, Summers confirmed that the phenomenon was not an illusion; while on earth, the human heart settles in an elliptical shape, but adaptation to the microgravity environment causes astronauts’ hearts to assume a more spherical shape.

“Dr. Summers was able to use the model to examine what we weren’t able to check otherwise, like seeing the response of a heart in lunar gravity or Martian gravity, which is very useful,” Martin said. “We have always enjoyed working with him, and his knowledge of physiology is always a plus for our lab.”

To perform their research, both Summers and Kiss have depended on wireless communication systems to transmit essential data from space to Earth. In the quest to improve that communications process are Lei Cao and John N. Daigle, professors of electrical engineering, and Ramanarayanan Viswanathan, chair and professor of electrical engineering.

Cao and his team received a Research Program Award from the NASA EPSCoR program in 2014. Their project, which is to be completed in 2017, will study better technologies for wireless communications in space. The Mississippi Space Grant Consortium, headquartered at UM, provides oversight of the state’s NASA EPSCoR program, which supports the development of new programs that will lead to increased research

competitiveness in the state. The project also includes subcontracts to Jackson State University and the NASA Jet Propulsion Laboratory.

The distance from the Earth to Mars varies due to the alignment of the planets and averages 140 million miles, resulting in communication delays of up to 20 minutes from a lander on Mars back to Earth. Wireless communication in space also must overcome large signal attenuation and heavy distortion due to noise caused by the atmosphere. In particular, water vapor affects higherfrequency microwave signals, and the sun’s corona can distort signals from spacecraft on the far side of the sun.

Cao’s project will focus on improving two aspects of wireless communication in space. In the reliable system currently used, data transmissions must be acknowledged upon receipt, and faulty

or corrupted files require multiple retransmissions that result in even longer delay periods. Cao and his team will explore improving this reliable model with the use of fountain codes, which will encode the data in ways that will allow it to be recovered without retransmission and will allow key data to be better protected against corruption. The other technology studied by the team, data fusion, may lead to better detection of signals that are distorted or buried in noise.

The project builds on the team’s long-time active research in joint source and channel coding for wireless communications, distributed signal detection and computer networks. The EPSCoR grant is related to previous research that was supported by a NASA seed grant. The team also is working with the National Science Foundation and private industry partners to further develop and broaden the applications of these technologies.

“The need to communicate ever-larger amounts of data for various exploration missions continues to escalate,” Cao said. “I’m inspired by the challenge and enjoy being part of the quest to find solutions.” CA

Scan this code to watch a NASA Video about the Seedling Growth-2 Experiment.