Experts in the News

In a monograph published in npj Microgravity, researchers including School of Biological Sciences Ph.D. student Iris Irby, reviewed a growing body of experimental evidence indicating that monocytes and macrophages are altered by the spaceflight environment. These findings have implications for a wide range of physiological processes, including innate immunity, acquired immunity, host defense, and tissue remodeling.

Sea cucumbers, scavengers of the seafloor that resemble the cylindrical vegetable, have been consumed as a delicacy in Asia for centuries. But in recent decades, they’ve been severely overharvested to a point that they are now quite rare. New research that Mark E. Hay, Regents Chair and the Harry and Anna Teasley Chair in Environmental Biology, helped conduct suggests their repopulation could play an important role in protecting and revitalizing another type of endangered marine organism: corals. (This also appeared at Statesville Record and Landmark.)

As they seep and calve into the sea, melting glaciers and ice sheets are raising global water levels at unprecedented rates. To predict and prepare for future sea-level rise, scientists need a better understanding of how fast glaciers melt and what influences their flow.  Now, a study by MIT scientists offers a new picture of glacier flow, based on microscopic deformation in the ice. The results show that a glacier’s flow depends strongly on how microscopic defects move through the ice.

“This study really shows the effect of microscale processes on macroscale behavior,” says Meghana Ranganathan who led the study as a MIT graduate student and is now a NOAA Climate & Global Change Postdoctoral Fellow in the School of Earth and Atmospheric Sciences. “These mechanisms happen at the scale of water molecules and ultimately can affect the stability of the West Antarctic Ice Sheet.” (This also appeared at Mirage News and Phys.org.)

It has been almost a quarter-century since M.G. Finn, K. Barry Sharpless, and Hartmuth C. Kolb published the paper that some refer to as the click manifesto. In it, the researchers presented a vision for synthetic chemistry that prioritizes quick and easy access to functional molecules. Today, click reactions can be found nearly everywhere organic bonds come in handy. They even garnered Sharpless, Carolyn Bertozzi, and Morten Meldal the Nobel Prize in Chemistry in 2022. The authors of the manifesto envisioned a future in which the grand challenge of synthetic chemistry would be figuring out not how to make a molecule but what molecule to make and what it would be good for, says M.G. Finn, professor and chair in the School of Chemistry and Biochemistry. The key to achieving that future: reactions of exceptional speed, ease, selectivity, and reliability.

A new paper published in the journal Science argues that traits that are highly variable and evolve quickly, over short time scales, are often the same ones that shape the direction of long-term evolution of new species. School of Biological Sciences Assistant Professor James Stroud, who was not involved in the research, says the study provides a fascinating insight: “As selection changes through time to chase new optima, the genetic variation of traits under selection may increase from this evolutionary back and forth,” he says. “This additive genetic variance, termed evolvability, is a window into evolution’s past.”

The Taklamakan and Gobi Desert (TGD) region has experienced a pronounced increase in summer precipitation, including high-impact extreme events, over recent decades. Despite identifying large-scale circulation changes as a key driver of the wetting trend, understanding the relative contributions of internal variability and external forcings remains limited. Researchers, including School of Earth and Atmospheric Sciences Professor Yi Deng, approached this problem by using a hierarchy of numerical simulations, complemented by diverse statistical analysis tools. The results offer strong evidence that the atmospheric internal variations primarily drive this observed trend. Specifically, recent changes in the North Atlantic Oscillation have redirected the storm track, leading to increased extratropical storms entering TGD and subsequently more precipitation. A clustering analysis further demonstrates that these linkages predominantly operate at the synoptic scale, with larger contributions from large precipitation events.

Weather forecasters talk about wind shear a lot during hurricane season, but what exactly is it?  School of Earth and Atmospheric Sciences Senior Academic Professional Zachary Handlos teaches meteorology in a part of the country that pays close attention to the Atlantic hurricane season. In this article, Handlos provides a quick look at wind shear, one of the key forces that can determine whether a storm will become a destructive hurricane. (This story also appeared at Scientific American, Down to Earth, and The Weather Network.)

Control of electrical doping is indispensable in any semiconductor device, and both efficient hole and electron doping are required for many devices. In organic semiconductors, however, electron doping has been essentially more problematic compared to hole doping because in general organic semiconductors have low electron affinities and require dopants with low ionization potentials that are often air-sensitive. In a recent study, a team of researchers, including Stephen Barlow of the School of Chemistry and Biochemistry and the Center for Organic Photonics and Electronics, adapted an efficient molecular doping method, so-called ion-exchange doping, to dope electrons in a polymeric semiconductor.

In the vast stretches of Georgia's saltwater marshes, where the land whispers to the ocean, a silent yet profound battle is waged beneath the surface. It's a struggle for survival and resilience, where the unassuming cordgrass, Spartina alterniflora, emerges as an ecological champion. But not without the help of its unseen allies-the intricate microbial communities thriving within its roots. Recent studies by Georgia Tech researchers, including School of Biological Sciences Professor and Associate Chair of Research Joel Kostka, have unveiled the pivotal role these microbes play in not only sustaining the cordgrass but also in bolstering the health of the entire coastal ecosystem. These findings, published in Nature Communications, shed light on the complex interplay between plant and microbe, revealing a symbiotic relationship that is as delicate as it is powerful. (This also appeared at Mirage News and  Phys.org.)

Evidence from the International Space Station suggests microbial populations are rapidly adapting to the spacecraft environment; however, the mechanism of this adaptation is not understood. Bacteriophages are prolific mediators of bacterial adaptation on Earth. In this study, researchers including School of Biological Sciences Ph.D. student Iris Irby, survey 245 genomes sequenced from bacterial strains isolated on the International Space Station for dormant (lysogenic) bacteriophages. The results correlate microbial adaptation in spaceflight to bacteriophage-encoded functions that may impact human health in spaceflight.

Forecasters are predicting a busy Atlantic hurricane season. The projections point to a potential weather double-whammy, said Zachary Handlos, senior academic professional at the School of Earth and Atmospheric Sciences. “The forecasts are expecting a higher frequency of storms this year, potentially aligned with record-breaking years like 2020 and 2005,” he noted. “But then on top of that there's a high chance of a few major hurricanes that could be thrown in the mix of all the named storms.” 

Thirty named storms formed in 2020. Fifteen Atlantic cyclones became hurricanes in 2005 including Katrina, which caused nearly $200 billion in damage and led to more than 1,800 deaths. Both seasons were influenced by La Niña patterns, which involve the cooling of tropical Pacific waters but lead to a reduction in vertical wind shear that acts as a brake against Atlantic hurricanes. This year, warming Atlantic waters and the expected arrival of a La Niña pattern are driving expectations for a hyperactive hurricane season. “The waters are already warmer than usual in the Atlantic, and warm water is a key ingredient for kind of starting off and forming hurricanes,” Handlos said. “If you mix that trend on top of the possible La Niña setup, it's just a potential recipe for disaster.” 

Researchers at Georgia Tech analyzed the weakening of ocean currents and how it could affect ocean life. A report published by Science studied the reaction of ocean currents to climate change, resulting in a potential decline in biological activity and nutrients in the North Atlantic. Using empirical data led by Jean Lynch-Stieglitz, chair of the School of Earth and Atmospheric Sciences, the study observed the sediments at the Gulf Stream's origin. The region plays an important role in the North Atlantic's biological activity, particularly the ocean currents that could weaken due to greenhouse gas emissions and climate change. (This also appeared at Phys.org.)