With the innovation of new materials and green composites, it is easy to overlook materials like bamboo and other natural fibres, explains UBCO Professor of Mechanical Engineering Dr. Abbas Milani. These fibres are now used in many applications such as clothing, the automotive industry, packaging and construction.

His research team has now found a way not only to strengthen these fibres, but reduce their tendency to degrade over time, making them even more environmentally friendly.

“Bamboo has nearly the same strength as a mild steel while exhibiting more flexibility,” says Dr. Milani, the founding director of the Materials and Manufacturing Research Institute. “With its low weight, cost and abundant availability, bamboo is a material that has great promise but until now had one big drawback.”

Bamboo is one of the world’s most harvested and used natural fibres with more than 30-million tonnes produced annually. However, its natural fibres can absorb water and degrade and weaken over time due to moisture uptake and weathering.

Using a process called plastination to dehydrate the bamboo, the research team then use it as a reinforcement with other fibres and materials. Then they cure it into a new high-performance hybrid biocomposite.

First developed by Gunther von Hagens in 1977, plastination has been extensively used for the long-term preservation of animal, human and fungal remains, and now has found its way to advanced materials applications. Plastination ensures durability of the composite material for both short- and long-term use, says Daanvir Dhir, the report’s co-author and recent UBC Okanagan graduate.

“The plastinated-bamboo composite was mixed with glass and polymer fibres to create a material that is lighter and yet more durable than comparable composites,” says Dhir. “This work is unique as there are no earlier studies investigating the use of such plastinated natural fibres in synthetic fibre reinforced polymer composites.”

Dhir says this new durable hybrid bamboo/woven glass fibre/polypropylene composite, treated with the plastination technique has a promising future.

Supported by industrial partner NetZero Enterprises Inc., the research shows that adding only a small amount of plastinated materials to the bamboo can increase the impact absorption capacity of the composite — without losing its elastic properties. This also lowers the material’s degradation rate.

More work needs to be done on the optimization of this process as Dhir says plastination is currently time-consuming. But he notes the benefit of discovering the right composition of plastinated natural fibres will result in a sizable reduction of non-degradable waste in many industries, with a lower environmental footprint.

Future studies are underway to optimize and investigate the effect of plastinating other natural fibres, such as flax and hemp. The researchers also suggest a life cycle analysis of the materials should be conducted under different applications and compared to non-plastinated samples. This will provide a better picture of the corresponding trade-off between the environmental footprint and mechanical durability effects.

“Biocomposites continue to find new applications under the circular economy paradigm,” adds Dr. Milani. “The innovations in the methods used to develop these composites will ensure benefits well into the future.”

Now, ketamine is getting a closer look.

Researchers from UBC Okanagan and the University of Exeter have identified ketamine as a potentially powerful tool in the fight against mental illness.

In a recent study published in the British Journal of Psychiatry, the research team found ketamine to have significant anti-depressant and anti-suicidal effects. They also found evidence that suggests its benefits don’t stop there.

Led by Psychology Professor Dr. Zach Walsh and doctoral student Joey Rootman — both based in the Irving K. Barber Faculty of Arts and Social Sciences — the research team arrived at this conclusion after analyzing more than 150 worldwide studies on the effects of sub-anesthetic ketamine doses for the treatment of mental illness. The study was co-led by Professor Celia Morgan and doctoral student Merve Mollaahmetoglu from the University of Exeter in the United Kingdom.

“We found strong evidence that indicates ketamine provides rapid and robust anti-depressant and anti-suicidal effects, but the effects were relatively short-lived,” explains Rootman. “However, repeated dosing appeared to have the potential to increase the duration of positive effects.”

Beyond these results, the study provides evidence that suggests ketamine may be helpful in the treatment of other disorders, including eating disorders, problematic substance use, post-traumatic stress and anxiety — though the evidence in these areas is scarce.

“What our research provides is an up-to-date overview and synthesis of where the knowledge on ketamine is at right now,” explains Rootman. “Our results signal that ketamine may indeed have a broader spectrum of potential applications in psychiatric treatment — and that tells us that more investigation is needed.”

This study serves as a foundation for fellow researchers looking to design ketamine-related projects and offers valuable data for clinicians considering using ketamine with their patients.

The results also help to satisfy the public’s appetite for information on innovative and emerging psychiatric treatments, says Dr. Walsh, explaining the review provides a relatively compact document with evidence regarding which ketamine treatments may be helpful for diverse diagnoses.

“As many as one in five Canadians will experience a mental illness this year, and the reality is that existing treatments don’t work for everyone,” he says. “As a result, many Canadians are curious about new approaches to help with these serious conditions.”

Overall, while Dr. Walsh acknowledges research into other treatment areas is just beginning, he finds the preliminary evidence encouraging.

“We need a lot more information on how these interventions could work — for example, administering the drug is only a part of treatment. We need to figure out what amount and type of psychotherapy would best compliment the drug intervention to really maximize potential benefits,” he explains. “With that being said, it is a truly exciting time for ketamine research. If it can deliver the relief that early evidence suggests it can, this could be among the most significant developments in mental health treatment in decades.”

Ames Lab has been a leader in rare-earths research since the middle of the 20^th century. Rare earth elements have a wide range of uses including clean energy technologies, energy storage, and permanent magnets. Discovery of new rare-earth compounds is part of a larger effort by scientists to expand access to these materials.

The present approach is based on machine learning (ML), a form of artificial intelligence (AI), which is driven by computer algorithms that improve through data usage and experience. Researchers used the upgraded Ames Laboratory Rare Earth database (RIC 2.0) and high-throughput density-functional theory (DFT) to build the foundation for their ML model.

High-throughput screening is a computational scheme that allows a researcher to test hundreds of models quickly. DFT is a quantum mechanical method used to investigate thermodynamic and electronic properties of many body systems. Based on this collection of information, the developed ML model uses regression learning to assess phase stability of compounds.

Tyler Del Rose, an Iowa State University graduate student, conducted much of the foundational research needed for the database by writing algorithms to search the web for information to supplement the database and DFT calculations. He also worked on experimental validation of the AI predictions and helped to improve the ML based models by ensuring they are representative of reality.

“Machine learning is really important here because when we are talking about new compositions, ordered materials are all very well known to everyone in the rare earth community,” said Ames Laboratory Scientist Prashant Singh, who led the DFT plus machine learning effort with Guillermo Vazquez and Raymundo Arroyave. “However, when you add disorder to known materials, it’s very different. The number of compositions becomes significantly larger, often thousands or millions, and you cannot investigate all the possible combinations using theory or experiments.”

Singh explained that the material analysis is based on a discrete feedback loop in which the AI/ML model is updated using new DFT database based on real-time structural and phase information obtained from our experiments. This process ensures that information is carried from one step to the next and reduces the chance of making mistakes.

Yaroslav Mudryk, the project supervisor, said that the framework was designed to explore rare earth compounds because of their technological importance, but its application is not limited to rare-earths research. The same approach can be used to train an ML model to predict magnetic properties of compounds, process controls for transformative manufacturing, and optimize mechanical behaviors.

“It’s not really meant to discover a particular compound,” Mudryk said. “It was, how do we design a new approach or a new tool for discovery and prediction of rare earth compounds? And that’s what we did.”

Mudryk emphasized that this work is just the beginning. The team is exploring the full potential of this method, but they are optimistic that there will be a wide range of applications for the framework in the future.

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Materials provided by DOE/Ames Laboratory. Note: Content may be edited for style and length.

The study, published in Nature Communications, helps to clarify a potential therapeutic strategy and adds to the knowledge of ASXL1 gene expression.

Epigenetics refers to chemical modifications of a cell’s genetic material that control how genes are expressed and affect the interpretation of the DNA code. Research shows epigenetics play a critical role in the development and progression of many diseases, including cancer.

“The epigenome in patients with these ASXL1 gene mutations is changed in a way that allows the cancer cells to switch on genes that are detrimental to the patients,” says Moritz Binder M.D., a Mayo Clinic hematologist and scientist, and the lead author of the study. Dr. Binder is a 2021 Gerstner Family Career Development awardee.

“These epigenetic changes don’t affect the DNA blueprint itself,” Dr. Binder explains. “It affects how to the blueprint is read — which pages to read and which pages not to read.”

Chronic myelomonocytic leukemia is a cancer that typically affects people 60 and older. It starts in blood-forming cells of the bone marrow and invades the blood. Nearly 40% of patients with chronic myelomonocytic leukemia have a mutation in the ASXL1 gene.

“Unfortunately, patients with ASXL1 mutations do not fare well and do not respond as well to the treatments currently available,” Dr. Binder says.

For the study, Dr. Binder and his team conducted a comprehensive multi-omics interrogation using a variety of high-throughput sequencing methods. Multi-omics offers the opportunity to understand the flow of information that underlies disease.

The researchers compared samples from patients with and without ASXL1 mutations and analyzed the activity of genes along with molecules around the DNA. The investigation included gene expression and several modifications affecting the packaging of the DNA.

“This allowed us to perform modeling to draw inference about the effect of epigenetic changes in isolation and in concert on leukemogenic gene expression in ASXL1-mutant chronic myelomonocytic leukemia,” Dr. Binder says.

Overall, they found that ASXL1 mutations are associated with the overexpression of key genes that drive leukemia.

“Our study supports the notion that several important leukemogenic driver genes are under the control of regulatory elements in the genome,” Dr. Binder says.

The data suggest that these regulatory elements are only functional in patients with ASXL1-mutant chronic myelomonocytic leukemia and may therefore represent new individualized therapeutic targets. Dr. Binder is planning to translate these findings into early phase clinical trials soon.

“Our study is the basis for ongoing work to further explore ways to target these patient-specific regulatory elements with novel small-molecule drugs, “Dr. Binder says. “With this approach, we hope to restore normal gene expression, or at least treat the cancer cells in a new way to overcome the detrimental effect of ASXL1 mutations.”

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Materials provided by Mayo Clinic. Original written by Susan Murphy. Note: Content may be edited for style and length.

The underlying physics driving these switchable materials is a mystery, though physicists suspect it has something to do with “electron correlations,” or effects from the interaction felt between two negatively charged electrons. These particle repulsions have little to no effect in shaping the properties in most materials. But in two-dimensional materials, these quantum interactions can be a dominating influence. Understanding how electron correlations drive electrical states can help scientists engineer exotic functional materials, such as unconventional superconductors.

Now, physicists at MIT and elsewhere have taken a significant step toward understanding electron correlations. In a paper appearing today in Science, the researchers reveal direct evidence of electron correlations in a two-dimensional material called ABC trilayer graphene. This material has previously been shown to switch from a metal to an insulator to a superconductor.

For the first time, the researchers directly detected electron correlations in a special insulating state of the material. They also quantified the energy scales of these correlations, or the strength of the interactions between electrons. The results demonstrate that ABC trilayer graphene can be an ideal platform to explore and possibly engineer other electron correlations, such as those that drive superconductivity.

“Better understanding of the underlying physics of superconductivity will allow us to engineer devices that could change our world, from zero-loss energy transmission to magnetically levitating trains,” says lead author Long Ju, assistant professor of physics at MIT. “This material is now a very rich playground to explore electron correlations and build even more robust phenomena and devices.”

Superlattice

An ABC trilayer graphene, stacked atop a layer of hexagonal boron nitride, is similar to the more well-studied magic-angle bilayer graphene, in that both materials involve layers of graphene — a material that is found naturally in graphite and can exhibit exceptional properties when isolated in its pure form. Graphene is made from a lattice of carbon atoms arranged in a hexagonal pattern, similar to chicken wire. Hexagonal boron nitride, or hBN, has a similar, slightly larger hexagonal pattern.

In ABC trilayer graphene, three graphene sheets are stacked at the same angle and slightly offset from each other, like layered slices of cheese. When ABC trilayer graphene sits on hBN at a zero-degree twist angle, the resulting structure is a moiré pattern, or “superlattice,” made up of periodic energy wells, the configuration of which determines how electrons flow through the material.

“This lattice structure forces electrons to localize, and sets the stage for electron correlations to have a huge impact on the material’s macroscopic property,” Ju says.

He and his colleagues sought to probe ABC trilayer graphene for direct evidence of electron correlations and to measure their strength. They first synthesized a sample of the material, creating a superlattice with energy wells, each of which can normally hold two electrons. They applied just enough voltage to fill each well in the lattice.

Electron boost

They then looked for signs that the material was in an ideal state for electron correlations to dominate and affect the material’s properties. They specifically looked for signs of a “flat band” structure, where all electrons have almost the same energy. The team reasoned that an environment hosting electrons with a wide range of energies would be too noisy for the tiny energy of electron correlations to have an effect. A flatter, quieter environment would allow for these effects to come through.

The team used a unique optical technique they developed to confirm that the material indeed has a flat band. They then tuned down the voltage slightly, so that only one electron occupied each well in the lattice. In this “half-filled” state, the material is considered a Mott insulator — a curious electrical state that should be able to conduct electricity like metal, but instead, due to electron correlations, the material behaves as an insulator.

Ju and his colleagues wanted to see if they could detect the effect of these electron correlations in a half-filled, Mott insulating state. They looked to see what would happen if they disturbed the state by moving electrons around. If electron correlations have any effect, such perturbations of electron configurations would meet resistance, since electrons naturally repel each other. For example, an electron that attempts to move to a neighboring well would be pushed back by the electron already occupying that well, even if that well can technically accommodate an additional electron.

In order to overcome this resistance, it would require an extra boost of energy — just enough to overcome the electron’s natural repulsion. The team reasoned that the magnitude of this boost would be a direct measure of the electron correlation’s strength.

The researchers supplied the extra boost using light. They shone light of different colors, or wavelengths, onto the material, and looked for a peak, or a single specific wavelength that the material absorbed. This wavelength corresponded to a photon with just enough energy to kick an electron into a neighboring half-filled well.

In their experiment, the team indeed observed a peak — the first direct detection of electron correlations in this specific moiré superlattice material. They then measured this peak to quantify the correlation energy, or the strength of the electron’s repulsive force. They determined this to be about 20 millielectronvolts, or 1/50 of an electronvolt.

The results show that strong electron correlations underlie the physics of this particular 2D material. Ju says the Mott insulating state is particularly important, as it is the parent state of unconventional superconductivity, the physics of which remains illusive. With this new study, the team has demonstrated that ABC trilayer graphen/hBN moiré superlattice is an ideal platform to explore and engineer the more exotic electrical states, including the unconventional superconductivity.

“Today, superconductivity happens only at very low temperatures in a realistic setting,” notes Ju, who says the team’s optical technique can be applied to other 2D materials to reveal similar exotic states. “If we can understand the mechanism of unconventional superconductivity, maybe we can boost that effect to higher temperatures. This material forms a foundation to understand and engineer even more robust electrical states and devices.”

This research was supported, in part, by the National Science Foundation, the Simons Foundation, and the MIT Skoltech program.

Scientists in each city used the same process to collect white clover samples and test them for a particular chemical anti-herbivore defense compound that also affects their stress tolerance for factors such as extreme heat and weather. Assistant Professor Kaitlin Stack Whitney from RIT’s Department of Science, Technology, and Society led a team of five environmental science students working on a senior capstone project to participate on Rochester’s behalf. In October 2018, they collected 650 samples at 41 sites along a straight path from downtown Rochester to Black Creek Park in North Chili along New York State Route 33A.

“We were picking through this tiny roadside weed, but it’s fascinating how you can unpack these global issues about urbanization and climate change by looking at this very overlooked plant,” said Stack Whitney. “There are these big global forces that are affecting how those plants are growing, what they’re doing, and whether or not they can respond to stresses in that very localized environment.”

The GLUE project was an opportunity for the RIT students to get hands-on, impactful research early in their scientific careers. Environmental science alumna Kristina Chomiak ’19, ’21 MS, who will begin pursuing her Ph.D. in sustainability in the fall, said the collaborative experiment helped solidify her interest in research.

“For me at that point personally I hadn’t had a ton of research experience,” said Chomiak. “It was exciting to be able to follow a protocol and actually conduct this wet lab research. And it was even better that it would be published and would be meaningful to the scientific community.”

Chomiak said she is excited to see the full results of the study and learn how the data they collected in Rochester compares to that found from other cities. She said that locally the team did not find a significant difference in adaptation between the urban and rural areas, but they hypothesize that is because Rochester has more snowfall than other cities involved in the study, meaning the white clover plants are less under attack here.

Participants in the first GLUE study, led by the University of Toronto Mississauga, are now discussing additional ways to leverage the data and organize follow-up studies. Stack Whitney plans to participate in at least five follow-up studies.

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Materials provided by Rochester Institute of Technology. Original written by Luke Auburn. Note: Content may be edited for style and length.