Experts in the News

India was the world’s third-most-prolific publisher of research papers in 2022, but it was ranked only 153rd for the number of citations it received per paper. Indeed, in 2020, about 30 percent of papers from India were not cited at all, compared with 20 percent in both the United States and China. These trends are mirrored in many other low- and middle-income countries whose researchers struggle to get published in high-impact journals. But despite this challenging publishing environment, some Indian scientists have produced influential, highly cited studies in a number of fields in the past few years. One of those researchers, Sachin Gunthe, who studies aerosols at the Indian Institute of Technology Madras, teamed with Pengfei Liu, assistant professor in the School of Earth and Atmospheric Sciences, to study the origins of air pollution in Delhi. 

Terry Maple, emeritus professor in the School of Psychology who is credited with transforming Zoo Atlanta from one of the worst in America to one of the best in the world, has died at 77. Atlantans of a certain age will recall that Zoo Atlanta was in a dismal state in the 1970s and 1980s before Maple took over as director in 1984. But Maple believed Zoo Atlanta had promise, and his first mission was to free Willie B, a western lowland gorilla, from the concrete bunker he lived in with a tire swing and television to keep him company. Maple, who had grown up in San Diego and frequented its world-famous zoo, envisioned a large outdoor habitat where Willie B. and other gorillas could live naturally rather than in confinement. (This story was also covered in The Atlanta Journal-Constitution.) 

Systems consisting of spheres rolling on elastic membranes have been used to introduce a core conceptual idea of general relativity: how curvature guides the movement of matter. However, such schemes cannot accurately represent relativistic dynamics in the laboratory because of the dominance of dissipation and external gravitational fields. A new study from School of Physics researchers demonstrates that an “active” object (a wheeled robot), which moves in a straight line on level ground and can alter its speed depending on the curvature of the deformable terrain it moves on, can exactly capture dynamics in curved relativistic spacetimes. The researchers' mapping and framework facilitate creation of a robophysical analog to a general relativistic system in the laboratory at low cost that can provide insights into active matter in deformable environments and robot exploration in complex landscapes. Researchers includes Hussain Gynai and Steven Tarr, graduate students; Emily Alicea-Muñoz, academic professional; Gongjie Li, assistant professor; and Daniel Goldman, Dunn Family Professor. 

Diverse and full of sea life, the Earth’s Devonian era — taking place more than 370 million years ago — saw the emergence of the first seed-bearing plants, which spread as large forests across the continents of Gondwana and Laurussia. However, a mass extinction event near the end of this era has long been the subject of debate. Some scientists argue the Late Devonian mass extinction was caused by large-scale volcanic eruptions, causing global cooling. Others argue a mass deoxygenation event caused by the expansion of land plants was to blame. 
A recently published study in the journal Communications Earth and Environment now posits that both factors played a role — and draws attention to the environmental tipping points the planet faces today. Chris Reinhard, associate professor in the School of Earth and Atmospheric Sciences, contributed to the study. (This story also appears in SciTechDaily and ScienceDaily.) 

The sudden buzz of a fly has most people flapping their hands wildly as if attempting to ward off an evil spirit. Seeing a wall or ceiling-hugger has others running quickly past or under, as if their mere shadow might prompt the insect to launch an aerial attack. Still others pick the fight response, choosing to squash the danger. But here’s the bug-zillion dollar question: Why do creepy-crawlies cause us to react this way? A 2018 Georgia Tech study that included Eric Schumacher, professor in the School of Psychology, found that the strongest neurological reaction elicited by bugs is disgust. It’s a result borne of a mix of things, from social conditioning and negative connotations to understanding their disease-carrying potential and, unfortunately, judging the book by its spindly, slimy, antennaed cover.

This roundup of some of the most unique excrement in the animal kingdom, showcasing the fascinating diversity of animal waste, includes a 2018 Georgia Tech study of how wombats manage to produce square-shaped feces. The study's authors include David Hu, professor in the School of Biological Sciences and the George W. Woodruff School of Mechanical Engineering, with an adjunct appointment in the School of Physics. As it turns out, the elastic nature of the marsupial's intestinal walls is a key factor.

The United States Air Force School of Aerospace Medicine, or USAFSAM, part of the Air Force Research Laboratory, or AFRL, is collaborating with Georgia Tech and the Georgia Tech Research Institute, or GTRI, on a new research project to design strains of probiotic bacteria that can provide health benefits to stimulate immune recognition of influenza. Developing more effective methods to combat influenza could reduce impacts on military readiness and training from outbreaks and augment vaccine efforts to increase force health protection capabilities. Brian Hammer, associate professor in the School of Biological Sciences, co-wrote a proposal that met Air Force requirements, and he will work with other researchers to develop the proof-of-concept project. 

Blimps are indeed part of this "Innovations" roundup, but it's the collaborative abilities of army ants that have led engineers from Northwestern University and the New Jersey Institute of Technology to speculate that the insects' behavioral principles and brains could one day be used to program swarms of robots. David Hu, professor in the School of Biological Sciences and the George W. Woodruff School of Mechanical Engineering (with an adjunct appointment in the School of Physics), is quoted regarding his research on fire ant raft constructions during flooding, comparing the insects to neurons in one large brain.

Pentoses are essential carbohydrates in the metabolism of modern lifeforms, but their availability during early Earth is unclear since these molecules are unstable. A new study led by the Earth-Life Science Institute (ELSI) at Tokyo Institute of Technology, Japan, reveals a chemical pathway compatible with early Earth conditions and by which C6 aldonates could have acted as a source of pentoses without the need for enzymes. Their findings provide clues about primitive biochemistry and bring us closer to understanding the Origins of Life. Charles Liotta, Regents' Professor Emeritus in the School of Chemistry and Biochemistry with a joint appointment in the School of Chemical and Biomolecular Engineering, is a co-author of the study. 

Ever wondered why your dog’s back-and-forth shaking is so effective at getting you soaked? Or how bugs, birds, and lizards can run across water—but we can’t? Or how about why cockroaches are so darn good at navigating in the dark? Those are just a few of the day-to-day mysteries answered in the new book How to Walk on Water and Climb Up Walls: Animal Movement and the Robots of the Future, by David Hu, professor in the School of Biological Sciences and the George W. Woodruff School of Mechanical Engineering, with an adjunct appointment in the School of Physics. The book answers questions you probably won’t realize you even had, but they’re questions with serious answers that span the worlds of physics, fluid mechanics, and biology. Throughout the book, Hu demonstrates the extraordinary value day-to-day curiosity brings to science.

Carbon nanotubes are a large family of carbon-based hollow cylindrical structures with unique physicochemical properties that have motivated research for diverse applications; some have reached commercialization. Recent actions in the European Union that propose to ban this entire class of materials highlight an unmet need to precisely define carbon nanotubes, to better understand their toxicological risks for human health and the environment throughout their life cycle, and to communicate science-based policy-driving information regarding their taxonomy, safe sourcing, processing, production, manufacturing, handling, use, transportation and disposal. In this Perspective, the authors discuss current information and knowledge gaps regarding these issues and make recommendations to provide research and development, and regulatory clarity, regarding the material properties of different carbon nanotube materials. A co-author of this article is Mijin Kim, assistant professor in the School of Chemistry and Biochemistry. 

Climate change is threatening the survival of plants and animals around the globe as temperatures rise and habitats change. Some species have been able to meet the challenge with rapid evolutionary adaptation and other changes in behavior or physiology. Dark-colored dragonflies are getting paler in order to reduce the amount of heat they absorb from the sun. Mustard plants are flowering earlier to take advantage of earlier snowmelt. Lizards are becoming more cold-tolerant to handle the extreme variability of our new climate. However, scientific studies show that climate change is occurring much faster than species are changing. James Stroud, assistant professor in the School of Biological Sciences, co-authored this article. (This article was also covered at The Good Men Project, Beaumont Enterprise, Yahoo! News and CapeTalk 567AM.)