Florida Atlantic Center for Connected Autonomy and Artificial Intelligence (CA-AI.fau.edu) researchers have “cracked the code” on interference when machines need to talk with each other—and people.

Electromagnetic waves make wireless connectivity possible but create a lot of unwanted chatter. Referred to as “electromagnetic interference,” this noisy byproduct of wireless communications poses formidable challenges in modern day dense Internet of Things and AI robotic environments. With the demand for lightning-fast data rates reaching unprecedented levels, the need to quell this interference is more pressing than ever.

Equipped with a breakthrough algorithmic solution, researchers from FAU Center for Connected Autonomy and AI, within the College of Engineering and Computer Science, and FAU Institute for Sensing and Embedded Network Systems Engineering (I-SENSE), have figured out a way to do that.

Their method, which is a first, dynamically fine-tunes multiple-input multiple-output (MIMO) links, a cornerstone of modern-day wireless systems such as Wi-Fi and cellular networks.

The researchers’ approach, published in a special issue of the journal IEEE Journal on Selected Areas in Communications and featured as a research highlight in Nature Reviews, demonstrates how their algorithmic method sculpts wireless waveforms to navigate the crowded frequency band. By simultaneously optimizing transmission in space and time, this algorithm could pave the way for pristine communication channels.

In field demonstrations, the researchers dynamically optimized MIMO wireless waveform shapes over a given frequency band to manage and avoid interference in machine-to-machine communications and showed the effectiveness of this method in real-world scenarios where interference is a common problem.

“We have pioneered the conceptual and practical groundwork for machines outfitted with multiple antennas to autonomously determine the most effective waveform shapes in both time and space domains for communication within a designated frequency band, even among extremely challenging interference and disturbances,” said Dimitris Pados, Ph.D., senior author, professor, director of the CA-AI and a fellow of I-SENSE in the Department of Electrical Engineering and Computer Science.

“By employing dynamic waveform machine learning in tandem across space and time, we believe that we have ‘cracked the code’ on mitigating electromagnetic interference.”

Researchers first conducted extensive simulations to validate the efficacy of this method against a barrage of interference scenarios from near-field to far-field and in both light and dense interference scenarios. These simulations highlighted the ability of the optimized waveforms, particularly joint space-time optimization, to maintain “clean” communications in extreme mixed-interference environments.

“In the realm of autonomous systems and machine-to-machine communications, secure, reliable and ‘clean’ communications are paramount, underscoring the importance of this breakthrough research at Florida Atlantic,” said Stella Batalama, Ph.D., dean, FAU College of Engineering and Computer Science.

“In the midst of chaos in modern communication, this innovative research offers a very promising avenue to address interference challenges in machine-to-machine communications where there are high volumes of devices and multiple networks.”

Researchers from the National University of Singapore (NUS) have discovered a salt adaptation mechanism in plants that facilitates chloride removal from the roots and enhances salinity tolerance. The work was published in the journal Nature Communications.

Soil salinity is one of the most deleterious environmental stress factors and increased salinity poses a growing challenge for crop production and adversely affects crop yields worldwide. The excess accumulation of soluble salts, especially sodium chloride (NaCl), in the root zone severely impedes plant growth, reducing crop productivity. Although chloride ions (Cl^–) are essential nutrients for plants at low concentrations, their excessive accumulation is toxic to the plant cells.

Plants have evolved various strategies to cope with such environmental stresses by employing various channels and transporters for maintaining ion balance (ion homeostasis) in their cells. While there is a better understanding of the sodium ion homeostasis under salt stress, removal of chloride ions is not well understood.

To address this, a research team led by Professor Prakash Kumar from the Department of Biological Sciences, NUS has uncovered a novel mechanism of plant adaptation to salt stress involving the NaCl-induced translocation of a specific chloride channel protein, AtCLCf.

Their work revealed that the AtCLCf protein is made and stored in the endomembrane system (the Golgi apparatus) under normal growth conditions. When the root cells are treated with salt, AtCLCf translocates to the plasma membrane (PM), where it helps to remove the excess chloride ions. This represents a novel mechanism to increase the plant’s salinity tolerance.

The research is a collaboration with Dr. Jiří Friml from the Institute of Science and Technology, Austria and Professor Xu Jian from Radboud University, The Netherlands.

The study also identified a transcription factor, AtWRKY9, that directly regulates the expression of the AtCLCf gene when the plant is under salt stress.

NaCl causes the AtCLCf protein to move from inside the cell (the Golgi) to the cell surface with the help of another protein called AtRABA1b/BEX5. If this movement is blocked by an inhibitor (brefeldin-A) or by modifying the BEX5 gene, it results in high salt sensitivity in plants.

Transgenic plants designed to produce additional AtCLCf gene showed increased salt tolerance in mutant forms of Arabidopsis plants lacking the CLCf gene. Collectively, these findings proved that AtCLCf is involved in the removal of excess chloride ions from root tissues to increase the salt tolerance of plants.

In order to understand how AtCLCf functions in plant cells, the researchers used several techniques such as fluorimetric measurement of liposomes incorporated with recombinant AtCLCf protein and chloride ion sensitive dye, as well as electrophysiological studies (patch clamp). These studies showed that AtCLCf works like a pump that swaps chloride ions with hydrogen ions, helping to remove excess chloride ions from the cells.

Prof Kumar said, “This represents an essential and previously unknown salt tolerance mechanism in Arabidopsis plants. This knowledge could be used to improve the salinity tolerance of crop plants in the future.”

There is a common belief that prescribed burning, thinning trees, and clearing underbrush reduce risks of the severity of future fires. But is that true? Sometimes anecdotal evidence or limited observations can create doubt.

Researchers from the USDA Forest Service Rocky Mountain Research Station, The Nature Conservancy, and the University of Montana dug deep into the scientific literature for a closer look. Spoiler alert: the answer is “yes”—proactive ecological forest management can change how fires behave and reduce wildfire severity, under a wide range of conditions and forest types.

Researchers found overwhelming evidence that in seasonally dry mixed conifer forests in the western U.S., reducing surface and ladder fuels and tree density through thinning, coupled with prescribed burning or pile burning, could reduce future wildfire severity by more than 60% relative to untreated areas.

The study results were published in Forest Ecology and Management. “Burning Questions Answered: New review examines 30 years of fuel treatment effects on wildfire severity” includes an overview of the research methods, key findings, management considerations, and links to related publications.

Fire is an essential component of many western forests. Yet historic fire suppression and climate change are contributing to increased fire activity and more severe wildfires, where overstory trees are killed. Treatments prepare a landscape, priming the next wildfire to burn at lower intensity, burning underbrush and smaller trees. This preserves more mature trees and helps foster a fire level that is more in balance with the landscape.

Kimberley Davis is a Forest Service Research Ecologist and led the project analyzing 40 studies where wildfire burned into different vegetation treatments, spanning 11 western states. The last review of this kind was over a decade ago, with many new case studies and scientific advances since then. Researchers examined effects of various treatments in different forest types, ranging from ponderosa pine forests in Arizona and New Mexico up to the subalpine zones of the northern Rocky Mountains.

The review hands natural resource professionals and communities the evidence needed to support continued investments in managing vegetation and fuels. “These treatments are very effective and the science clearly shows that they can reduce fire severity,” said Davis.

While responses varied, generally the combination of thinning and prescribed burning showed the greatest impact on reducing future fire severity. Areas that were only thinned had less benefit in reducing wildfire severity. Prior low or moderate severity wildfire also reduced fire severity in subsequent wildfires, although to a lesser extent than thinning with prescribed burning.

Time also matters. “As treatments get older, they’re less effective,” said Davis. After 10 years treatments were less than half as effective as younger treatments, underscoring the importance of repeated or “maintenance” treatments.

In the long run, forest fuel reduction projects can improve conditions for fire fighters responding to wildfires. They mitigate long-term losses of carbon and wildlife habitat and protect watersheds from more severe wildfire. Treatments also create more options for determining appropriate responses to lightning and other unplanned ignitions.

When designed to meet the unique needs of the forest type and nearby communities, these tools can support the longevity of clean water resources, wildlife habitat, and outdoor places to work and recreate.

“This review shows that treatments can reduce future wildfire severity, which is key to protecting important forest habitats,” said Kerry L. Metlen, forest ecologist with The Nature Conservancy and a contributing author of the review.

“This gives us hope that by accelerating the use of these tools, in conjunction with work to promote fire adapted communities, we can address the wildfire crisis together.”