Oak Ridge National Laboratory’s John Field provided biomass feedstock production expertise to the report focused on the role of the bioeconomy in U.S. decarbonization strategies, which was produced by the Department of Energy’s DECARB program.

The report examined the role of biomass in reducing greenhouse gas emissions across the economy, including opportunities to reach negative emissions. It includes data from the ORNL-led 2016 Billion-Ton Report that identified potential biomass from agricultural and forestry residues, wastes and bioenergy crops.

The latest 2023 Billion-Ton Report identifies up to 1.7 billion tons per year of potential biomass, including winter oilseed crops for jet biofuels.

Carbon-negative bioenergy is expected to be essential to a net-zero emissions economy and could account for 4% to 11% of the nation’s total energy mix by 2050, according to the DECARB report.

Further information: https://www.energy.gov/eere/bioenergy/2023-billion-ton-report-assessment-us-renewable-carbon-resources

Scientists have long been working to understand the Cascadia Subduction Zone’s subterranean structures and mechanics, in order to delineate places most susceptible to quakes, how big they might be and what warning signs they might produce. There is no such thing as predicting an earthquake; rather, scientists try to forecast probabilities of multiple scenarios, hoping to help authorities design building codes and warning systems to minimize the damage when something happens.

A newly published study promises to greatly advance this effort. A research vessel towing an array of the latest geophysical instruments along almost the entire zone has produced the first comprehensive survey of the many complex structures beneath the seafloor. These include the geometry of the down-going ocean plate and overlying sediments, and the makeup of the overriding North American plate. The study was just published in the journal Science Advances.

“The models currently in use by public agencies were based on a limited set of old, low-quality 1980s-era data,” said Suzanne Carbotte, a marine geophysicist at Columbia University’s Lamont-Doherty Earth Observatory, who led the research. “The megathrust has a much more complex geometry than previously assumed. The study provides a new framework for earthquake and tsunami hazard assessment.”

With funding from the U.S. National Science Foundation, the data was gathered during a 41-day cruise in 2021 by Lamont’s research vessel, the Marcus G. Langseth. Researchers aboard the ship penetrated the seafloor with powerful sound pulses and read the echoes, which were then converted into images, somewhat similar to how physicians create interior scans of the human body.

One key finding: the megathrust fault zone is not just one continuous structure, but is divided into at least four segments, each potentially somewhat insulated against movements of the others. Scientists have long debated whether past events, including the 1700 quake, ruptured the entire zone or just part of it — a key question, because the longer the rupture, the bigger the quake.

The data show that the segments are divided by buried features including big faults, where opposing sides slide against each other perpendicular to the shore. This might help buffer against movement on one segment translating to the next. “We can’t say that this definitely means only single segments will rupture, or that definitely the whole thing will go at once,” said Harold Tobin, a geophysicist at the University of Washington and coauthor of the study. “But this does upgrade evidence that there are segmented ruptures.”

The imagery also suggests the causes of the segmentation: the rigid edge of the overriding North American continental plate is composed of many different kinds of rocks, formed at different times over many tens of millions of years, with some being denser than others. This variety in the continental rocks causes the incoming, more pliable oceanic plate to bend and twist to accommodate differences in overlying pressure. In some places, segments go down at relatively steep angles, in others at shallow ones.

The researchers zeroed in on one segment in particular, which runs from southern Vancouver Island alongside Washington state, more or less ending at the Oregon border. The subterranean topography of other segments is relatively rough, with oceanic features like faults and subducted seamounts rubbing up against the upper plate — features that might erode the upper plate and limit how far any quake may propagate within the segment, thus limiting the quake’s size. In contrast, the Vancouver Island to south alongside Washington State segment is quite smooth. This means that it may be more likely to rupture along its entire length at once, making it potentially the most dangerous section.

Also in this segment, the seafloor is subducting under the continental crust at a shallow angle relative to the other segments. In the other segments, most of the earthquake-prone interface between the plates lies offshore, but here the study found the shallow subduction angle means it probably extends directly under Washington’s Olympic Peninsula. This might magnify any shaking on land. “It requires a lot more study, but for places like Tacoma and Seattle, it could mean the difference between alarming and catastrophic,” said Tobin.

With funding from the U.S. Geological Survey, a consortium of state and federal agencies and academic institutions has already been poring over the data since it became available to sort through the implications.

As for tsunami hazard, that is “still a work in progress,” said Kelin Wang, a research scientist at the Geological Survey of Canada who was not involved in the study. Wang’s group is using the data to model features of the seafloor off Vancouver Island that might generate tsunamis. (In general, a tsunami occurs when the deep seafloor moves up or down during a quake, sending a wave to the surface that concentrates its energy and gathers height as it reaches shallower coastal waters.) Wang said his results will go to another group that models tsunamis themselves, and after that to another group that analyzes the hazards on land.

Practical assessments that could affect building codes or other aspects of preparedness may be published as early as next year, say the researchers. “There’s a whole lot more complexity here than was previously inferred,” said Carbotte.

Their study showed that mutating the orco gene in Harpegnathos saltator jumping ants dramatically decreased the number of olfactory neurons, suggesting that Orco is necessary for the development and life of these cells. The findings, published in Science Advances, offer insights into the cellular and molecular basis of how animals socialize.

“Understanding how the nervous system develops is among the most pressing challenges in modern neuroscience,” said Bogdan Sieriebriennikov, a postdoctoral fellow in NYU’s Department of Biology and the study’s first author.

Sensing smell and mutant ants

Ants have evolved approximately 400 smell receptors — a number closer to humans than most other insects — thanks to their use of pheromone communication.

“Ants, like humans, are highly social and display cooperative social behavior, and thus provide an ideal system to study sensory-mediated social behavior,” explained Hua Yan, assistant professor of biology at the University of Florida and the study’s senior author. “Expanded odorant receptor genes allow ants to ‘talk’ to each other in a large society with hundreds, thousands, or up to a million individuals.”

Even for humans, who rely on other senses for communication, smell is essential.

“Loss of function of odorant receptor neurons leads to deficits in olfactory sensing and is often associated with social isolation, neurological disorders such as schizophrenia, and social disorders such as autism,” added Yan.

To better understand how ants’ sense of smell influences their social interactions, NYU researchers previously created the first genetically engineered ants by using CRISPR to edit the orco gene. These “mutant” ants, lacking the Orco protein, experienced changes to their smell organs and had difficulty interacting.

“We found that the antennae — which are the ‘nose’ of the ant — had very few cells. They were almost empty, suggesting that the cells that sense smell were absent from the mutant ants,” said Yan.

Neuron survival depends on Orco

In their new study in Science Advances, the researchers used single-nucleus gene expression profiling of ant antennae and fluorescence microscopy to analyze olfactory cell development. It emerged that mutant insects lacking Orco lose most of their olfactory neurons before adulthood.

“The cells appear to be made normally, and they start developing — growing, changing shape, and switching on certain genes they will need later, such as odorant receptors,” noted Sieriebriennikov. “Once the developing cells turn on the odorant receptors, very soon they start dying in massive amounts.”

This neuronal death may be because of stress. As the odorant receptors in the mutant ants cannot form a complex with Orco to travel to the cell membrane, the newly made receptors clog the organelles, leading to stress and death.

Such neuronal death may also show patterns particular to social insects. “So far, these unique processes have not been found in solitary insects and may provide important evidence of evolution of neural development to adapt to the expansion of odorant receptor genes,” said Kayli Sieber, a doctoral candidate at the University of Florida and the co-first author of the study.

Interestingly, some odorant receptors survived even without Orco. The cells in which they were present also expressed other types of receptors, suggesting that the activity they facilitate is essential for neuronal development.

“Some neurons must periodically ‘fire’ to develop properly. Without Orco, smell cells did not ‘fire’ and complete their development, leading to their death,” said Sieriebriennikov.

The researchers also found that some odorant receptors are present in non-smell cells, such as mechanosensory neurons that detect motion and glia, which wrap around neurons and help them function. This may be due to imperfect regulation of genes, which causes odorant receptors to be accidentally activated by nearby genomic regions that are normally regulating other genes in other cells. Alternatively, the receptors may have a new function in these cells, like the odorant receptors found in the glia of C. elegans worms or human sperm.

“Turning on odorant receptor genes in the cells that are not smell-sensing could be totally useless for the organism — but then again, evolution tends to make use of such mistakes to give existing genes new function, so perhaps there is some exciting new role of odorant receptors in non-smell cells that we will discover in the future,” noted Sieriebriennikov.

“Our findings enhance our understanding of social insects’ sensory systems, including olfactory neural development that establishes a framework for social communication,” said Yan.

Other study authors include Olena Kolumba, Jakub Mlejnek, and Shadi Jafari. This research was supported by the National Institutes of Health (R01-DC020203, T32-DC015994), the National Science Foundation Industry-University Cooperative Research Center for Arthropod Management Technologies (#IIP1821914), and the Human Frontier Science Program (LT000010/2020-L).

Their simulations show that small variations in layers of water ice — too subtle for ground-penetrating radar instruments to resolve — can cause constructive interference between radar waves. Such interference can produce reflections whose intensity and variability match observations to date — not only in the area proposed to be liquid water, but across the so-called south polar layered deposits.

“I can’t say it’s impossible that there’s liquid water down there, but we’re showing that there are much simpler ways to get the same observation without having to stretch that far, using mechanisms and materials that we already know exist there,” said Daniel Lalich, research associate in the Cornell Center for Astrophysics and Planetary Science. “Just through random chance you can create the same observed signal in the radar.”

Lalich is the first author of “Small Variations in Ice Composition and Layer Thickness Explain Bright Reflections Below Martian Polar Cap Without Liquid Water,” published June 7 in Science Advances.

Robotic explorers have provided extensive evidence that water flowed on the surface of ancient Mars, including at a former river delta now under investigation by NASA’s Perseverance rover. Relying on a radar instrument that can probe below the surface to detect water ice and potentially hidden aquifers, members of the European Space Agency-led Mars Express orbiter’s science team in 2018 announced they’d discovered a lake buried below the south polar cap.

The implications were enormous: Where there is liquid water, there could be microbial life.

But while the same bright radar reflections would likely indicate a subglacial lake on Earth, Lalich said, the temperature and pressure conditions on Mars are very different.

Using simpler models, Lalich previously showed that the bright radar signals could be created in the absence of liquid water, but he said assumptions about layers of frozen carbon dioxide below the ice cap likely were incorrect.

The new research tells a more complete story, he said, closing gaps in the radar interference hypothesis with more realistic modeling. The thousands of randomly generated layering scenarios were based only on conditions known to exist at the Martian poles, and varied the ice layers’ composition and spacing in ways that would be expected over tens or hundreds of miles.

Those slight adjustments sometimes produced bright subsurface signals consistent with observations in each of the three frequencies used by the Mars Express orbiter’s MARSIS radar instrument, a partnership between NASA and the Italian Space Agency. Likely for a simple reason, Lalich argues: Radar waves bouncing off layers spaced too closely for the instrument to resolve may be combined, amplifying their peaks and troughs.

“This is the first time we have a hypothesis that explains the entire population of observations below the ice cap, without having to introduce anything unique or odd,” Lalich said. “This result where we get bright reflections scattered all over the place is exactly what you would expect from thin-layer interference in the radar.”

While not ruling out the potential for some future detection by more capable instruments, Lalich said he suspects the story of liquid water and potential life on the red planet ended long ago.

“The idea that there would be liquid water even somewhat near the surface would have been really exciting,” Lalich said. “I just don’t think it’s there.”

The research was supported by NASA.

The study, by Bangor University and Technion- Israel Institute of Technology, published in the scientific journal People and Nature, involved city-dwellers, and showed how paying visual attention to greenery, rather than human-made structures, can alleviate anxiety and enhance restorative feelings.

The 117 urban residents who took part in the study, were guided on a 45-minute urban walk, while wearing eye-tracking glasses. They were instructed to focus their gaze on trees, plants, lawns and flowers, man-made structures or a mix of both. This unique methodology revealed that a participants’ focus on nature was associated with improvements in various mental health metrics, including anxiety levels and feelings of restorativeness.

Dr Whitney Fleming, a lecturer in Human Geography at Bangor University explained the findings, saying,

“We found that the individuals who were guided to direct their gaze more frequently at green elements reported a significant reduction in anxiety, with trees showing the most substantial positive effect.”

The study highlights a strong link between observing green elements, especially trees, and an increase in perceived restorativeness, suggesting that even brief interactions with nature can provide mental health benefits.”

Urban Design Implications

These insights offer valuable guidance for urban planners and architects, suggesting that integrating more natural features into city landscapes can play a crucial role in enhancing the mental well-being of residents. “The Nature Gaze” study supports the idea of urban environments that promote engagement with nature, highlighting a simple yet effective strategy for improving urban mental health.

“COVID-19 forced educators to adjust their educational best practices to an unfamiliar virtual classroom, and professional development was no different,” said Karen Jo Matsler, assistant professor in practice for UTeach at UTA and lead author on the study.

Ramon Lopez, professor of physics, was coprincipal investigator on the project. Chandralekha Singh from the University of Pittsburgh was a co-author.

QIS is a new field of science and technology that combines physical science, math, computer science and engineering, and it is key to everyday items like cellphones and solar technology. However, most high schools don’t teach the subject, preventing students from acquiring the skills they need to pursue lucrative jobs.

As part of a $1 million grant from the National Science Foundation in 2021, Matsler and her colleagues aimed to teach QIS to high school science teachers, who could then bring this newly acquired knowledge to their classrooms.

“However, the pandemic made us scrap our original plans for in-person training to an online environment,” Matsler said. “We knew that teaching QIS online would be challenging, but we were pleasantly surprised how well it worked.”

Matsler, Lopez and the team found that what worked best for teaching QIS online was sending participants some of the material in advance to allow them to become familiar with the topics. Then during the sessions, the educators used Zoom — with features such as chat, polling and breakout rooms — to keep the individuals engaged in learning. They also led activities where the learners had a chance to practice teaching the material, another technique that helped individuals stay engaged.

To avoid cognitive overload, the team found main discussions needed to be kept at 15 to 30 minutes, each with breakout sessions lasting five to seven minutes, with a total session time of about 90 to 120 minutes.

“This gave participants ample opportunities to discuss the quantum concepts in small groups varying from two to six participants,” Matsler said. “During these small discussions, leaders rotated in and out of the rooms to check on the participants, clarify instructions and answer questions.”

The instructors also recommend “icebreaker” activities to increase community engagement in virtual learning.

“These icebreaker activities can easily be used to engage students, take attendance and gauge how much the individuals know about the upcoming subject lesson,” Matsler said. “A key element to all of this online learning is making sure the learners feel they are in a safe community to learn and exchange ideas.”

The team also found that short, relevant videos helped teach complicated topics. They recommend keeping the chat function operational during videos to allow participants to ask questions and stay engaged.

“Ideally, QIS is taught in a classroom with hands-on activities to allow learners to see and touch how things like maglev trains and quantum levitation work,” Matsler said. “However, our experiences show that embedding appropriate pedagogy and content with online learning can be effective at teaching these topics. Understanding there is an effective virtual option is important as the country ramps up its efforts to accelerate quantum research and development to stay competitive with other countries in this field.”

The study will be published on June 7 in the journal Science Advances.

Before surgeons remove the pancreas from patients with severe, painful chronic pancreatitis, they first harvest insulin-producing tissue clusters, called islets, and transplant them into the vasculature of the liver. The goal of the transplant is to preserve a patient’s ability to control their own blood-glucose levels without insulin injections.

Unfortunately, the process inadvertently destroys 50-80% of islets, and one-third of patients become diabetic after surgery. Three years post-surgery, 70% of patients require insulin injections, which are accompanied by a list of side effects, including weight gain, hypoglycemia and fatigue.

In the new study, researchers transplanted islets from the pancreas to the omentum — the large, flat, fatty tissue that covers the intestines — instead of the liver. And, to create a healthier microenvironment for the islets, the researchers adhered the islets to the omentum with an inherently antioxidant and anti-inflammatory biomaterial, which rapidly transforms from a liquid to a gel when exposed to body temperature.

In studies with mouse and non-human primates, the gel successfully prevented oxidative stress and inflammatory reactions, significantly improving survival and preserving function of transplanted islets. It marks the first time a synthetic antioxidant gel has been used to preserve function of transplanted islets.

“Although islet transplantation has improved over the years, long-term outcomes remain poor,” said Northwestern’s Guillermo A. Ameer, who led the study. “There is clearly a need for alternative solutions. We have engineered a cutting-edge synthetic material that provides a supportive microenvironment for islet function. When tested in animals, we were successful. It kept islet function maximized and restored normal blood sugar levels. We also report a reduction in units of insulin that animals required.”

“With this new approach, we hope that patients will no longer have to choose between living with the physical pain of chronic pancreatitis or the complications of diabetes,” added Jacqueline Burke, a research assistant professor of biomedical engineering at Northwestern and the paper’s first author.

An expert in regenerative engineering, Ameer is the Daniel Hale Williams Professor of Biomedical Engineering at Northwestern’s McCormick School of Engineering, a Professor of Surgery at Northwestern University Feinberg School of Medicine and founding director of the Center for Advanced Regenerative Engineering.

‘Compromised quality of life’

For patients living without a pancreas, side effects such as managing blood-sugar levels can be a lifelong struggle. By secreting insulin in response to glucose, islets help the body maintain glycemic control. Without functioning islets, people must closely monitor their blood-sugar levels and frequently inject insulin.

“Living without functional islets places a great burden on patients,” Burke said. “They must learn to count carbs, dose insulin at the appropriate time and continuously monitor blood glucose. This consumes much of their time and mental energy. Even with great care, exogeneous insulin therapy is not as effective as islets for maintaining glucose control. Patients with out-of-range blood glucose will develop complications, such as blindness and amputation. Our goal is for this biomaterial to preserve the islets, so patients can live a normal life — a life without diabetes.”

“It’s a compromised quality of life,” Ameer said. “Instead of multiple insulin injections, we would love to collect and preserve as many islets as possible.”

But, unfortunately, the current standard of care for preserving islets often leads to poor outcomes. After the surgery to remove the pancreas, surgeons isolate islets from the pancreas and transplant them to the liver through portal vein infusion. This intraportal perfusion procedure has several common complications. Islets in direct contact with blood flow undergo an inflammatory response, more than half of the islets die, and transplanted islets can cause dangerous clots in the liver. For those reasons, physicians and researchers have been searching for an alternate transplantation site.

In previous clinical studies, researchers transplanted islets to the omentum instead of the liver in order to bypass issues with clotting. To secure the islets on the omentum, physicians used plasma from the patients’ own blood to form a biologic gel. While the omentum appeared to work better than the liver as a transplantation site, several issues, including clots and inflammation, remained.

“There’s been significant interest in the research and medical communities to find an alternate islet transplantation site,” Ameer said. “The results from the omentum study were encouraging, but outcomes were varied. We believe that’s because the use of the patients’ blood and the added components required to create the biologic gel can affect reproducibility among patients.”

A citrate solution

To protect the islets and improve outcomes, Ameer turned to the citrate-based biomaterials platform with inherent antioxidant properties developed in his laboratory. Used in products approved by U.S. Food and Drug Administration for musculoskeletal surgeries, citrate-based biomaterials have demonstrated the ability to control the body’s inflammatory responses. Ameer set out to investigate whether a version of these biomaterials with biodegradable and temperature-responsive phase-changing properties would provide a superior alternative to a biologic gel obtained from blood.

In cell cultures, both mouse and human islets stored within the citrate-based gel maintained viability much longer than islets in other solutions. When exposed to glucose, the islets secreted insulin, demonstrating normal functionality. Moving beyond cell cultures, Ameer’s team tested the gel in small and large animal models. Liquid at room temperature, the material turns into a gel at body temperature, so it’s simple to apply and easily stays in place.

In the animal studies, the gel effectively secured the islets onto the omentum of the animals. Compared to the current methods, more islets survived, and, over time, the animals restored normal blood glucose levels. According to Ameer, the success is partially due to the new material’s biocompatibility and antioxidant nature.

“Islets are very sensitive to oxygen,” Ameer said. “They are affected by both too little oxygen and too much oxygen. The material’s innate antioxidant properties protect the cells. Plasma from your own blood doesn’t offer the same level of protection.”

Integrating into tissues

After about three months, the body resorbed 80-90% of the biocompatible gel. But, at that point, it was no longer needed.

“What was fascinating is that the islets regenerated blood vessels,” Ameer said. “The body generated a network of new blood vessels to reconnect the islets with the body. That is a major breakthrough because the blood vessels keep the islets alive and healthy. Meanwhile, our gel is simply resorbed into the surrounding tissue, leaving little evidence behind.”

Next, Ameer aims to test his hydrogel in animal models over a longer period of time. He said the new hydrogel also could be used for various cell replacement therapies, including stem cell-derived beta cells for treating diabetes.

The study, “Phase-changing citrate macromolecule combats oxidative pancreatic islet damage, enables islet engraftment and function in the omentum,” was supported by the U.S. Department of Defense and the National Science Foundation.