Tech

An analysis published in the Journal of Computer Assisted Learning highlights 20 years of research on the use of virtual reality (VR) in K-12 schools and higher education.

Investigators examined 149 articles from 2000-2019 from three major academic databases. They found that VR technology was implemented more extensively in higher education than in K-12 education, with basic science, social science, and health and medicine being the most popular disciplines. Desktop-based VR interventions were most often used for inquiry-based learning while immersive VR interventions enabled by commercial head-mounted displays have led to an increase of direct instruction. Overall, VR interventions had a medium effect on learning, with discipline, level of immersion, and instructional design influencing this effect.

The review provides some practical implications for K-12 and university teachers, and the authors propose an agenda for future research on the use of VR in education.

"Previous research has established the effectiveness of VR usage in education, the next step is to understand the reasons behind it so that it can be further improved," said lead author Heng Luo, PhD, of Central China Normal University.

New research published in Insect Conservation and Diversity indicates that artificial light at night likely interferes with the courtship and mating of bioluminescent fireflies.

For the study, investigators exposed courting pairs of fireflies to five colors of light at two intensities, and they recorded changes in the rate, brightness, and pattern of male advertisement flashes, as well as how often females responded.

All artificial light treatments significantly suppressed courtship activity, but bright amber light had the greatest impact on female receptivity. This suggests that artificial lights that are closest in color to firefly bioluminescence may be the most disruptive to firefly courtship.

"It's definitely concerning, because many ecologically-minded people are pushing the use of amber lights to safely light up streets and parks. But we're finding that no color of light is safe for fireflies--they need the dark," said co-author Avalon C.S. Owens, a PhD candidate at Tufts University.

The article is part of the journal's Special Issue: Impacts of artificial lighting at night on insect conservation.

A recent study, affiliated with UNIST has unveiled a novel system, capable of producing hydrogen and electricity quickly and effectively while eliminating carbon dioxide (CO?) emissions significantly.

Published in the January 2021 issue of Nano Energy, this breakthrough has been carried out by Professor GunTae Kim and his research team in the School of Energy and Chemical Engineering at UNIST. In this study, the research team succeeded in developing a membrane-free aqueous metal-CO? battery. Unlike the existing aqueous metal-CO? systems, the new battery is not only easier to manufacture, but also allows continuous operation with one type of electrolyte.

The research team designed a membrane-free (MF) Mg-CO2 battery, as an advanced approach to sequester CO2 emissions by generating electricity and value-added chemicals without any harmful by-products. According to the research team, their MF Mg-CO2 battery operates based on the indirect utilization of CO2 with facile hydrogen generation process. It has been also found that the new battery exhibits high faradaic efficiency of 92.0%.

"In order to translate the newly-developed laboratory-scale MF Mg-CO2 battery technology into a commercial reality, we have envisioned an operational prototype system that produces electricity and value-added chemicals, as a cornerstone to better support sustainable human life from CO2 and earth-abundant renewable power (e.g., wind, solar, seawater)," noted the research team.

The MF Mg-CO2 battery system has a structure similar to that of hydrogen fuel cells for use in cars, since it only requires a Mg-metal negative electrode, an aqueous electrolyte, and a positive-electrode catalyst. However, unlike the existing fuel cells, they are based on aqueous electrolytes. As a result, the newly-developed MF Mg-CO2 battery had successfully sequestered CO2 emissions by generating electricity and value-added chemicals without any harmful by-products.

"Our findings indicate great benefits for the newly-developed MF Mg-CO2 battery technology to produce various value-added chemicals of practical significance and electricity from CO2 without any wasted by-products," noted the research team. "Through this we have opened the door to electrochemical utilization of CO2 with indirect circulation for future alternative technologies."

A new study in Nicotine & Tobacco Research, published by Oxford University Press, finds that the use of high-strength nicotine e-cigarettes can help adults with schizophrenia spectrum disorders quit smoking.

Some 60-90% of people with schizophrenia smoke cigarettes, compared to 15-24% of the general population. The researchers from the University of Catania, in collaboration with colleagues from City University of New York and Weill Medical College of Cornell University, have assessed here the feasibility of using a high-strength nicotine e-cigarette to modify smoking behavior in people with schizophrenia spectrum disorders who smoke cigarettes. In this study 40 adults with schizophrenia spectrum disorders who smoked and did not intend to reduce or quit smoking participated in a 12-week study using Juul e-cigarettes loaded with 5% nicotine pods with a follow-up visit at 24 weeks. Researchers measured smoking frequency, smoking reduction, carbon monoxide expired air reduction, smoking cessation, and continuous abstinence 24 weeks after the study began.

Some 40% of participants had stopped smoking traditional cigarettes by the end of 12 weeks. Researchers observed an overall, sustained 50% reduction in smoking or complete smoking abstinence in 92.5% of participants at the end of 12 weeks. Researchers also observed an overall 75% reduction in median daily cigarette consumption from 25 to 6, by the end of the 12 weeks.

After six months, 24 weeks after the study began, 35% of participants had completely stopped smoking conventional tobacco cigarettes, while continuing to use e-cigarettes. Researchers here also measured a significant decrease in daily cigarette consumption was also confirmed at the end of 24 weeks. The study's authors report that 57.5% of participants reduced their cigarette usage by over 50%.

Additionally, researchers found that participants' mean blood pressure, heart rate and weight measurably decreased between the start of the study and the 12-week follow up. Positive and negative symptoms of schizophrenia were not significantly different after using e-cigarettes throughout the whole duration of the study. At the end of the study 61.9% of participants reported feeling more awake, less irritable, and experiencing greater concentration, and reduced hunger.

"Smoking is the primary cause of the 15-25 years mortality gap between users of mental health services and the general population, said one of the paper's authors, Riccardo Polosa, professor of Internal Medicine at the University of Catania (Italy). "This study demonstrates that switching to high-strength nicotine e-cigarettes is a feasible highly effective smoking cessation method for smokers who have schizophrenia. And it improves their quality of life too!"

When scientists at the Institute of Science and Technology (IST) Austria looked at developing zebrafish embryos, they observed an abrupt and dramatic change: within just a few minutes, the solid-like embryonic tissue becomes fluid-like. What could cause this change and, what is its role in the further development of the embryo? In a multidisciplinary study published in the journal Cell, they found answers that could change how we look at key processes in development and disease, such as tumor metastasis.

To learn more about how a tiny bunch of cells develops into complex systems like fish, humans or animals as big as elephants, many scientists turn to the zebrafish (Danio rerio). It has a few advantages that made it one of the favorite model organisms of developmental biologists like Nicoletta Petridou, until recently postdoc at the research group of Carl-Philipp Heisenberg at the Institute of Science and Technology (IST) Austria. First, the small striped fish develop within just a few days, the embryos do so outside their mothers and are transparent - one can see every organ as it develops. While looking at zebrafish embryos a few hours after fertilization, in a previous study Nicoletta Petridou and her colleagues discovered a sudden change in the viscosity of the embryonic tissue - a measure of a tissue's resistance to deformation: "At this early stage, the tissues forming the embryo are very rigid, but suddenly, viscosity drops by ten times and the tissue flows very quickly - it fluidizes," the biologist explains.

Small change - big effect

Simultaneously, the embryo starts changing its shape for the first time, thereby entering a phase called morphogenesis. In a new study, the researchers looked deeper into what is happening at the cellular level during tissue fluidization. "What we found was that before this fluidization, an individual cell is connected to four to five of its neighboring cells. At the onset of fluidization, however, it has only three to four neighbor connections left," says Petridou. Could this small change in the cells' connectivity really be responsible for a ten-fold difference in the tissue viscosity? "This was when we turned to physics to provide us with a framework that could explain this effect," says the molecular and developmental biologist.

"So, Nicoletta found this massive drop in tissue viscosity at the macroscopic level that is apparently not matching what is going on at the microscopic cell connectivity level. This is a key point of physics: to link what is going on at the microscopic level with the macroscopic level," says Bernat Corominas-Murtra, until recently part of Edouard Hannezo's research group. Using an analogy with material science, the team realized that each cell having four connected neighbors was actually a very special threshold: physicist James Clerk Maxwell in the 19th century had already realized that structures such as bridges or networks below this connectivity level cannot be rigid anymore. This precisely matched the experimental observations of tissue fluidization occurring when cells are connected to less than four neighbors. Using this analogy, the team was able to show that the fluidization of the tissue displays features of a phase transition, which is the transition from one state of matter like solid, liquid or gas to another.

A critical point

After finding this resemblance to phase transitions, the scientists challenged their theory by manipulating the cells' connectivity. No matter the manipulation, the critical point of connectivity was enough to explain the abrupt changes in tissue viscosity experimentally observed. Furthermore, they traced all expected features of phase transitions from the physics of non-living systems. "It is unique to be able to trace all the expected properties of a phase transition in a real, living system. Especially because the phase transition theory is made for systems with a billion components, whereas, here we are talking about a system with a few hundred components," Corominas-Murtra explains enthusiastically.

But, if the loss of only one connection per cell is enough to trigger such a significant change of the embryo's tissue, how can an accidental change be avoided? "What was very puzzling for me was that it seems to be a very risky process for the embryo. Now that we know there is a critical point, we can ask what regulates its balance. One of the regulations we found is the timing of cell divisions that defines how tissue connectivity, and thus its viscosity, changes in space and time," says Petridou, who has just started her own research group at the European Molecular Biology Laboratory (EMBL) in Heidelberg, Germany.

From fish embryos to tumor research

The transition is essential for the further development of the tiny fish embryo. However, it also seems to play a role in cancer growth. When a tumor metastasizes, recent studies have shown the tissue also abruptly changes from solid to liquid, which could allow cancer cells to move around more easily. "If one can trace this critical point, it opens ways to manipulate it," says Petridou. "We don't have the tools yet to do so, but instead of conceptually focusing on the large number of genes that could play a role in cancer growth, one could focus on this critical point that eventually causes this transition."

Working together with researchers from two different research groups at IST Austria proved essential for the scientists' success. "I remember spending hours in the lab with Nicoletta trying to figure out what she was doing and the other way around. We needed to reach a common language, which takes a lot of time but is very rewarding. Multidisciplinarity is an attitude," says Bernat Corominas-Murtra, who has recently started working as an assistant professor at the Austrian Karl-Franzens University Graz.

Finding the best materials for tomorrow's electronics is the goal of Professor Emanuele Orgiu of the Institut national de la recherche scientifique (INRS). Among the materials in which Professor Orgiu is interested, some are made of molecules that can conduct electricity. He has demonstrated the role played by molecular vibrations on electron conductivity on crystals of such materials. This finding is important for applications of these molecular materials in electronics, energy and information storage. The study, conducted in collaboration with a team from the INRS and the University of Strasbourg (France), was published in the prestigious Advanced Materials journal.

Scientists were interested in observing the relationship between the structure of materials and their ability to conduct electricity. To this end, they measured the speed of propagation of electrons in crystals formed by these molecules. In their study, the authors compared two perylene diimide derivatives, which are semiconducting molecules of interest because of their use on flexible devices, smart clothes or foldable electronics. The two compounds encompassed within the study have similar chemical structure but featured very different conduction properties.

With the goal of determining what caused this difference, the research group was able to establish that the different molecular vibrations composing the material were responsible for the different electrical behaviour observed in devices. "For a current to flow through a material, electrons must 'hop' from one molecule to the neighbouring one. Depending on the level of 'movement' of the molecules, which depends on the amplitude and energy of the related vibrations (called phonons), the electrons can move more or less easily through the material," explains Professor Orgiu, whose research team is the first to demonstrate which vibrations have the greatest influence on electron flows.

An Ad Hoc Molecular Design to Make Electrons Travel Faster

This breakthrough paves the way for the development of even more efficient materials for electronics. "By knowing what type of vibrations allows charges to move more easily, we are providing chemists with a formula for synthesizing the right materials, rather than going in blindly," explains Marc-Antoine Stoeckel. This research opens up new applications that could not be envisaged with silicon, the most widely used material in electronics, including computers.

Professor Orgiu collaborated with INRS Professor Luca Razzari to measure the vibrations of the molecules. The two researchers are now working on a new spectroscopic technique that would enable them to visualize the vibrations when electrons are present. This will allow them to see if charges affect molecular vibrations.

Researchers at the University of Surrey have found that non-invasive skin swab samples may be enough to detect COVID-19.

The most widely used approach to testing for COVID-19 requires a polymerase chain reaction (PCR) test, which involves taking a swab of the back of the throat and far inside the nose.

In a paper published by Lancet E Clinical Medicine, chemists from Surrey teamed up with Frimley NHS Trust and the Universities of Manchester and Leicester to collect sebum samples from 67 hospitalised patients - 30 who had tested positive for COVID-19 and 37 who had tested negative. The samples were collected by gently swabbing a skin area rich in sebum - an oily, waxy substance produced by the body's sebaceous glands - such as the face, neck or back.

The researchers analysed the samples by using liquid chromatography mass spectrometry and a statistical modelling technique called Partial Least Squares - Discriminant Analysis to differentiate between the COVID-19 positive and negative samples.

The Surrey team then found that patients with a positive COVID-19 test had lower lipid levels - or dyslipidemia - than their counterparts with a negative test. The accuracy of the study's results increased further when medication and additional health conditions were controlled.

Dr Melanie Bailey, co-author of the study from the University of Surrey, said:

"Unfortunately, the spectre of future pandemics is firmly on the top of the agenda for the scientific community. Our study suggests that we may be able to use non-invasive means to test for diseases such as COVID-19 in the future - a development which I am sure will be welcomed by all."

Matt Spick, co-author of the study from the University of Surrey, said:
"COVID-19 damages many areas of metabolism. In this work, we show that the skin lipidome can be added to the list, which could have implications for the skin's barrier function, as well as being a detectable symptom of the disease itself."

Dr George Evetts, Consultant in Anaesthesia & Intensive Care Medicine at Frimley Park Hospital, said:
"Investigating new methods of diagnosis and surveillance in a new disease such as COVID-19 that has had such a devastating effect on the world is vital. Sebum sampling is a simple, non-invasive method that shows promise for both diagnostics and monitoring of the disease in both a healthcare and a non-healthcare setting."

Nanograined metals and alloys, whose grain size is less than 100 nm, exhibit extremely high strength and high ductility, possessing excellent mechanical properties. Nanograined materials, however, have a large number of grain boundaries and hence high total grain boundary energy. At a temperature higher than a critical temperature, grains in nanograined materials will grow spontaneously to reduce the grain boundary energy, leading to thermal instability of the materials. A common approach to enhance the thermal stability is via grain boundary energy segregation, which thermodynamically lowers the grain boundary energy and kinetically pins the movement of grain boundaries, thereby enhancing the critical temperature of recrystallization. However, the role of mechanical stresses in the thermal stability has not been systematically studied yet.

A recently published paper entitled "Grain boundary segregation and relaxation in nano-grained polycrystalline alloys", in SCIENCE CHINA Physics, Mechanics & Astronomy, Vol. 62, Issue 2, 2021, systematically studies the thermal stability of nanograined alloys, by analytic investigation of three coupled behaviors between grain boundaries and crystalline grains among chemical concentrations and mechanical stresses. The three coupled behaviors are 1) the coupling between grain boundary stress and grain stress, 2) grain boundary segregation, and 3) the coupling between concentration and stress. Finally, a novel thermodynamic criterion is developed for the thermal stability of nanograined alloys, which shows stresses play an extremely role there. The authors of the paper are ZHANG Tong-Yi, GAO Yingxin and SUN Sheng from Materials Genome Institute, Shanghai University.

The thermodynamic energy is divided into the mechanical energy and the chemical energy and both are coupled each other. The analysis of mechanical energy considers the grain boundary eigen-stress and the eigen-strain induced by grain boundary segregation and develops a hybrid method to solve the eigen-stress and eigen-strain coupling problem. The chemical thermodynamics analysis considers the difference in the chemical potentials of pure elements in grain boundaries and in grains, and hence proposes a generalized McLean adsorption isotherm, which naturally includes the stress term. Based on the three coherent coupling effects, a novel criterion is developed for the thermal stability of nanograined alloys, and quantitatively and analytically expressed by the difference in molar free energy between a nanograined polycrystalline alloy and its single crystal counterpart. A positive or negative difference in molar free energy indicates the nanograined alloy is thermal unstable or stable.

Ni1-xMox binary alloys are taken as an example to illustrate, with figures, the theoretical results and the roles of each parameters involved in the analytic criterion. The present study shows that stresses play a vital role in the thermal stability of nanograined alloys. Any criterions without considering internal stresses would partially estimate the thermal stability of nanograined alloys.

Parkinson's disease (PD) is a well-studied neurodegenerative disorder that affects between 7 and 10 million people worldwide. Despite PD being a recurrent topic in the medical literature for over 200 years, its mechanisms are largely unclear, and existing treatments are aimed at improving the patient's symptoms.

Among PD's most common symptoms are motor problems, including as tremors, slowness, and muscular rigidity. These, combined with many non-motor symptoms, cause many PD patients to develop facial abnormalities, such as face skin problems and difficulties making facial expressions. Such problems are not to be taken lightly, as one's face plays a crucial role not only in self-esteem, but also when interacting with others. Unfortunately, facial changes in PD patients are difficult to track and quantify with conventional techniques.

But what if artificial intelligence (AI) could provide the tools we needed all along? In a recent study published in Brain Supplement, a team of scientists from Okayama University, Japan, tested whether modern facial detection and analysis algorithms could be useful in the context of PD. Led by Dr. Koh Tadokoro of the Department of Neurology, the team recruited 193 people, half of which were PD patients at different stages of the disease and the other half were healthy control subjects. The subjects were taken to a consulting room in the University's clinic, and the researchers took a single photograph of their face without giving any special instructions.

Once the pictures were taken, the team used commercially available AI software to detect the subjects' faces and analyze some of their attributes; namely apparent age, expressed emotion, and facial skin condition. Through statistical analyses, they explored whether AI-based algorithms could find significant differences in these attributes between the control group and the PD group.

Interestingly, the age gap, which is the apparent age estimated by the software minus the real age of the subject, was a factor that differed between both groups. On average, the age gap for PD patients was higher than for healthy subjects, revealing that the former tended to look slightly older than their actual age in the eyes of the AI. In addition, the facial expression of PD patients was more likely to be classified as "expressionless" compared with healthy subjects, who were significantly more likely to carry an expression classified as "happiness." On the other hand, in terms of skin condition, the researchers found no noticeable differences between both groups.

Overall, the strategy adopted in the study and the results gathered could pave the way for incorporating AI-based software into future research on the symptoms of PD. The approach the team used is relatively simple and cost-effective, as Dr. Tadokoro explains: "Whereas most previous studies evaluated the facial changes caused by PD during movement or tasks, we found evidence of specific facial changes based solely on a single photograph using modern AI ." Additionally, the team also noted some limitations of facial analysis software, such as performing worse in some regards for people with darker skin or being less accurate when estimating the age of Asians. Such problems can and should be addressed before the software is put to use in clinical research.

In short, it is possible that AI-based tools bear untapped potential for the rapid, quantitative analysis of patients with PD. Excited about the results, Dr. Tadokoro remarks: "We hope our study accelerates the use of AI technology for the diagnosis and treatment of patients with Parkinson's and other neurodegenerative diseases. " Let us hope future researchers take note of the power of AI in the context of neurological disorders to push the field forward towards a deeper understanding.

Superconductivity is a complete loss of electrical resistance. Superconductors are not merely very good metals: it is a fundamentally different electronic state. In normal metals, electrons move individually, and they collide with defects and vibrations in the lattice. In superconductors, electrons are bound together by an attractive force, which allows them to move together in a correlated way and avoid defects.

In a very small number of known superconductors, the onset of superconductivity causes spontaneous electrical currents to flow. These currents are very different from those in a normal metal wire: they are built into the ground state of the superconductor, and so they cannot be switched off. For example, in a sheet of a superconducting material, currents might appear that flow around the edge, as shown in the figure.

This is a very rare form of superconductivity, and it always indicates that the attractive interaction is something unusual. Sr2RuO4 is one famous material where this type of superconductivity is thought to occur. Although the transition temperature is low - Sr2RuO4 superconducts only below 1.5 Kelvin - the reason why it superconducts at all is completely unknown. To explain the superconductivity in this material has become a major test of physicists' understanding of superconductivity in general. Theoretically, it is very difficult to obtain spontaneous currents in Sr2RuO4 from standard models of superconductivity, and so if they are confirmed then a new model for superconductivity - an attractive force that is not seen in other materials - might be required.

The way that these electrical currents are detected is subtle. Subatomic particles known as muons are implanted into the sample. The spin of each muon then precesses in whatever magnetic field exists at the muon stopping site. In effect, the muons act as sensitive detectors of magnetic field, that can be placed inside the sample. From such muon implantation experiments it has been found that spontaneous magnetic fields appear when Sr2RuO4 becomes superconducting, which shows that there are spontaneous electrical currents.

However, because the signal is subtle, researchers have questioned whether it is in fact real. Onset of superconductivity is a major change in the electronic properties of a material, and maybe this subtle additional signal appeared because the measurement apparatus was not properly tuned.

In this work, researchers at the Max Planck Institute for Chemical Physics of Solids, the Technical University of Dresden, and the Paul Scherrer Institute (Switzerland) have shown that when uniaxial pressure is applied to Sr2RuO4, the spontaneous currents onset at a lower temperature than the superconductivity. In other words, the transition splits into two: first superconductivity, then spontaneous currents. This splitting has not been clearly demonstrated in any other material, and it is important because it shows definitively that the second transition is real. The spontaneous currents must be explained scientifically, not as a consequence of imperfect measurement. This may require a major re-write of our understanding of superconductivity.

KAIST researchers and their collaborators at home and abroad have successfully demonstrated a new methodology for direct near-field optical imaging of acoustic graphene plasmon fields. This strategy will provide a breakthrough for the practical applications of acoustic graphene plasmon platforms in next-generation, high-performance, graphene-based optoelectronic devices with enhanced light-matter interactions and lower propagation loss.

It was recently demonstrated that 'graphene plasmons' - collective oscillations of free electrons in graphene coupled to electromagnetic waves of light - can be used to trap and compress optical waves inside a very thin dielectric layer separating graphene from a metallic sheet. In such a configuration, graphene's conduction electrons are "reflected" in the metal, so when the light waves "push" the electrons in graphene, their image charges in metal also start to oscillate. This new type of collective electronic oscillation mode is called 'acoustic graphene plasmon (AGP)'.

The existence of AGP could previously be observed only via indirect methods such as far-field infrared spectroscopy and photocurrent mapping. This indirect observation was the price that researchers had to pay for the strong compression of optical waves inside nanometer-thin structures. It was believed that the intensity of electromagnetic fields outside the device was insufficient for direct near-field optical imaging of AGP.

Challenged by these limitations, three research groups combined their efforts to bring together a unique experimental technique using advanced nanofabrication methods. Their findings were published in Nature Communications on February 19.

A KAIST research team led by Professor Min Seok Jang from the School of Electrical Engineering used a highly sensitive scattering-type scanning near-field optical microscope (s-SNOM) to directly measure the optical fields of the AGP waves propagating in a nanometer-thin waveguide, visualizing thousand-fold compression of mid-infrared light for the first time.

Professor Jang and a post-doc researcher in his group, Sergey G. Menabde, successfully obtained direct images of AGP waves by taking advantage of their rapidly decaying yet always present electric field above graphene. They showed that AGPs are detectable even when most of their energy is flowing inside the dielectric below the graphene.

This became possible due to the ultra-smooth surfaces inside the nano-waveguides where plasmonic waves can propagate at longer distances. The AGP mode probed by the researchers was up to 2.3 times more confined and exhibited a 1.4 times higher figure of merit in terms of the normalized propagation length compared to the graphene surface plasmon under similar conditions.

These ultra-smooth nanostructures of the waveguides used in the experiment were created using a template-stripping method by Professor Sang-Hyun Oh and a post-doc researcher, In-Ho Lee, from the Department of Electrical and Computer Engineering at the University of Minnesota.

Professor Young Hee Lee and his researchers at the Center for Integrated Nanostructure Physics (CINAP) of the Institute of Basic Science (IBS) at Sungkyunkwan University synthesized the graphene with a monocrystalline structure, and this high-quality, large-area graphene enabled low-loss plasmonic propagation.

The chemical and physical properties of many important organic molecules can be detected and evaluated by their absorption signatures in the mid-infrared spectrum. However, conventional detection methods require a large number of molecules for successful detection, whereas the ultra-compressed AGP fields can provide strong light-matter interactions at the microscopic level, thus significantly improving the detection sensitivity down to a single molecule.

Furthermore, the study conducted by Professor Jang and the team demonstrated that the mid-infrared AGPs are inherently less sensitive to losses in graphene due to their fields being mostly confined within the dielectric. The research team's reported results suggest that AGPs could become a promising platform for electrically tunable graphene-based optoelectronic devices that typically suffer from higher absorption rates in graphene such as metasurfaces, optical switches, photovoltaics, and other optoelectronic applications operating at infrared frequencies.

Professor Jang said, "Our research revealed that the ultra-compressed electromagnetic fields of acoustic graphene plasmons can be directly accessed through near-field optical microscopy methods. I hope this realization will motivate other researchers to apply AGPs to various problems where strong light-matter interactions and lower propagation loss are needed."

CHAMPAIGN, Ill. -- Agricultural scientists who study climate change often focus on how increasing atmospheric carbon dioxide levels will affect crop yields. But rising temperatures are likely to complicate the picture, researchers report in a new review of the topic.

Published in the Journal of Experimental Botany, the review explores how higher temperatures influence plant growth and viability despite the greater availability of atmospheric CO2, a key component of photosynthesis.

Excessive heat can reduce the efficiency of enzymes that drive photosynthesis and can hinder plants' ability to regulate CO2 uptake and water loss, the researchers write. Structural features can make plants more - or less - susceptible to heat stress. Ecosystem attributes - such as the size and density of plants, the arrangement of leaves on plants or local atmospheric conditions - also influence how heat will affect crop yields.

The review describes the latest scientific efforts to address these challenges.

"It's important to have an understanding of these issues across scales - from the biochemistry of individual leaves to ecosystem-level influences - in order to really tackle these problems in an informed way," said lead author Caitlin Moore, a research fellow at the University of Western Australia and an affiliate research fellow at the Institute for Sustainability, Energy, and Environment at the University of Illinois Urbana-Champaign. Moore led the review with Amanda Cavanagh, another U. of I. alumna now at the University of Essex in the U.K.

"Historically, there's been a lot of focus on rising CO2 and the impact that it has on plants," said co-author Carl Bernacchi, a professor of plant biology and of crop sciences and an affiliate of the Carl R. Woese Institute for Genomic Biology at the U. of I. "And it is an important factor, because we are changing that carbon dioxide concentration enormously. But it's a small part of the bigger story. Once you throw changing temperatures into the mix, it completely messes up our understanding of how plants are going to respond."

"Take Rubisco, the key enzyme that fixes carbon dioxide into sugars, making life on Earth possible," Cavanagh said. "Rubisco speeds up as the temperature increases, but it's also prone to making mistakes."

Instead of fixing carbon dioxide by binding it to sugars, a key step in photosynthesis, Rubisco sometimes fixes oxygen, initiating a different pathway that wastes a plant's resources. Higher temperatures make this more likely, Cavanagh said. At even higher temperatures, the enzyme will begin to lose its structural integrity, making it ineffective.

Excessive heat can also undermine a plant's reproductive output. Other heat-sensitive enzymes are essential to the light-harvesting machinery of plants or play a role in moving sugars to different plant tissues, allowing the plant to grow and produce grains or fruits.

"If these little molecular machines are pushed out of the temperature range that's optimal, then they can't do their job," Cavanagh said.

When temperatures rise too high, plant leaves open the pores on their surfaces, called stomata, to cool themselves. Stomata also allow plants to absorb carbon dioxide from the atmosphere, but when they're fully open, the leaf can lose too much moisture.

"Temperature affects the atmosphere above the plant," Moore said. "As the atmosphere heats up, it can hold additional water, so it's pulling more water from the plants."

Scientists at Illinois and elsewhere are looking for ways to enhance crop plants' resilience in the face of these changes. Moore, whose work focuses on ecosystem-scale factors, said new tools that can help screen plants on a large scale are essential to that effort. For example, satellites that can detect changes in chlorophyll fluorescence in plants can indicate whether a crop is under heat stress. These changes in fluorescence are detectable before the plant shows any outward sign of heat stress - such as their leaves turning brown. Developing these tools may enable farmers to respond more quickly to crop stress before too much damage is done.

Cavanagh, who studies the molecular biology and physiology of plants, said some plants are more heat tolerant than others, and scientists are searching their genomes for clues to their success.

"For example, you can look at wild Australian relatives of rice that are growing in much harsher climates than most paddy rices," she said. "And you see that their enzymes are primed to work more efficiently at hotter temperatures."

One goal is to transfer heat-tolerant genes to cultivated rice varieties that are more susceptible to heat stress.

Other strategies include engineering structures that pump more CO2 to the site of carbon fixation to improve Rubisco efficiency; altering the light-gathering properties of leaves at the tops and bottoms of plants to even out distribution of sunlight and maintain moisture levels; and changing the density of stomata to improve their control of CO2 influx and moisture loss.

Collaboration between scientists focused on different scales of ecosystem and plant function - from the atmospheric to the molecular - is essential to the success of efforts to build resilience in crop plants, the researchers said.

"The world is getting hotter at a shocking rate," Cavanagh said. "And we know from global models that each increase in gross temperature degree Celsius can cause 3% to 7% losses in yield of our four main crops. So, it's not something we can ignore.

"What makes me optimistic is the realization that so much work is going into globally solving this problem," she said.

A team of scientists led by Nanyang Technological University, Singapore (NTU Singapore) has developed a device that can deliver electrical signals to and from plants, opening the door to new technologies that make use of plants.

The NTU team developed their plant 'communication' device by attaching a conformable electrode (a piece of conductive material) on the surface of a Venus flytrap plant using a soft and sticky adhesive known as hydrogel. With the electrode attached to the surface of the flytrap, researchers can achieve two things: pick up electrical signals to monitor how the plant responds to its environment, and transmit electrical signals to the plant, to cause it to close its leaves.

Scientists have known for decades that plants emit electrical signals to sense and respond to their environment. The NTU research team believe that developing the ability to measure the electrical signals of plants could create opportunities for a range of useful applications, such as plant-based robots that can help to pick up fragile objects, or to help enhance food security by detecting diseases in crops early.

However, plants' electrical signals are very weak, and can only be detected when the electrode makes good contact with plant surfaces. The hairy, waxy, and irregular surfaces of plants make it difficult for any thin-film electronic device to attach and achieve reliable signal transmission.

To overcome this challenge, the NTU team drew inspiration from the electrocardiogram (ECG), which is used to detect heart abnormalities by measuring the electrical activity generated by the organ.

Transmitting electrical signals to create an on demand plant-based robot

As a proof-of concept, the scientists took their plant 'communication' device and attached it to the surface of a Venus flytrap - a carnivorous plant with hairy leaf-lobes that close over insects when triggered.

The device has a diameter of 3 mm and is harmless to the plant. It does not affect the plant's ability to perform photosynthesis while successfully detecting electrical signals from the plant. Using a smartphone to transmit electric pulses to the device at a specific frequency, the team elicited the Venus flytrap to close its leaves on demand, in 1.3 seconds.

The researchers have also attached the Venus flytrap to a robotic arm and, through the smartphone and the 'communication' device, stimulated its leaf to close and pick up a piece of wire half a millimetre in diameter.

Their findings, published in the scientific journal Nature Electronics in January, demonstrate the prospects for the future design of plant-based technological systems, say the research team. Their approach could lead to the creation of more sensitive robot grippers to pick up fragile objects that may be harmed by current rigid ones.

Picking up electrical signals to monitor crop health monitoring

The research team envisions a future where farmers can take preventive steps to protect their crops, using the plant 'communication' device they have developed.

Lead author of the study, Chen Xiaodong, President's Chair Professor in Materials Science and Engineering at NTU Singapore said: "Climate change is threatening food security around the world. By monitoring the plants' electrical signals, we may be able to detect possible distress signals and abnormalities. When used for agriculture purpose, farmers may find out when a disease is in progress, even before full?blown symptoms appear on the crops, such as yellowed leaves. This may provide us the opportunity to act quickly to maximise crop yield for the population."

Prof Chen, who is also Director of the Innovative Centre for Flexible Devices (iFLEX) at NTU, added that the development of the 'communication' device for plants monitoring exemplifies the NTU Smart Campus vision which aims to develop technologically advanced solutions for a sustainable future.

Next generation improvement: Liquid glue with stronger adhesive strength

Seeking to improve the performance of their plant 'communication' device, the NTU scientists also collaborated with researchers at the Institute of Materials Research and Engineering (IMRE), a unit of Singapore's Agency for Science, Technology and Research (A*STAR).

Results from this separate study, published in the scientific journal Advanced Materials in March, found that by using a type of hydrogel called thermogel - which gradually transforms from liquid to a stretchable gel at room temperature - it is possible to attach their plant 'communication' device to a greater variety of plants (with various surface textures) and achieve higher quality signal detection, despite plants moving and growing in response to the environment.

Elaborating on this study, co-lead author Professor Chen Xiaodong said, "The thermogel-based material behaves like water in its liquid state, meaning that the adhesive layer can conform to the shape of the plant before it turns into a gel. When tested on hairy stems of the sunflower for example, this improved version of the plant 'communication' device achieved four to five times the adhesive strength of common hydrogel and recorded significantly stronger signals and less background noise."

Co-lead author of the Advanced Materials study and Executive Director of IMRE, Professor Loh Xian Jun, said: "The device can now stick to more types of plant surfaces, and more securely so, marking an important step forward in the field of plant electrophysiology. It opens up new opportunities for plant-based technologies."

Moving forward, the NTU team is looking to devise other applications using the improved version of their plant 'communication' device.

A quadruple fusion optical and ultrasound imaging system has been developed that allows diagnosis of eye conditions or tumors or to see the environment inside the body using a transparent ultrasound transducer.

Professor Chulhong Kim of POSTECH's Department of Electrical Engineering, Convergence IT Engineering, and Mechanical Engineering, Dr. Byullee Park of Department of Convergence IT Engineering, Ph.D. candidate Jeongwoo Park of School of Interdisciplinary Bioscience and Bioengineering, Professor Hyung Ham Kim of Department of Convergence IT Engineering, and Professor Unyong Jeong of Department of Materials Science and Engineering, in joint research with Professor Hong Kyun Kim of Kyungpook National University School of Medicine have together developed a transparent ultrasound transducer1 and has used it to produce the world's first quadruple fusion imaging system that integrates ultrasound imaging, photoacoustic imaging, optical coherence tomography, and fluorescence imaging. These research findings were published in the Proceedings of the National Academy of Sciences of the United States of America (PNAS) on March 8, 2021.

There is a growing interest in multimodal imaging systems that obtain various images and information by combining ultrasound and optical imaging devices. Among them, an ultrasound transducer is a device that produces images by generating ultrasound and functions as an image sensor in ultrasonic examinations. But it was not optically transparent and difficult to let lasers pass through effectively, and therefore had limitations to be coaxially combined with an optical imaging device.

To solve this issue, the research team developed a highly sensitive transparent ultrasound transducer which the laser can effectively pass through. This newly developed device obtains quadruple fusion images of ultrasound, photoacoustic, optical coherence, and fluorescence in one imaging system for the first time.

Using the quadruple fusion imaging system combined with a transparent ultrasound transducer integrated into an ophthalmic imaging system, the researchers were able to observe the corneal neovascularization, structural changes, cataracts, inflammation, and other epidemiological changes in the rat eye.

In addition, when used as a tumor imaging device, the researchers were able to multiparametrically visualize the oxygen saturation of surrounding blood vessels and tissues in a melanoma-afflicted mouse without using a contrast agent. With molecular imaging, breast cancer diagnosis is now possible as demonstrated by acquiring and observing various images of a mouse with breast cancer through injecting a contrast agent that is harmless to the human body.

These research findings are anticipated to be widely applicable to various industries where ultrasound and optical sensors are used, such as healthcare and medical fields, mobile, automobiles, robotics, non-destructive testing, as well as ophthalmological diseases and tumor imaging diagnosis.

PHILADELPHIA - Imposter syndrome is a considerable mental health challenge to many throughout higher education. It is often associated with depression, anxiety, low self-esteem and self-sabotage and other traits. Researchers at the Sidney Kimmel Medical College at Thomas Jefferson University wanted to learn to what extent incoming medical students displayed characteristics of imposter syndrome, and found that up to 87% of an incoming class reported a high or very high degree of imposter syndrome.

"Distress and mental health needs are critical issues among medical students," says Susan Rosenthal, MD, lead author of the study published in the journal Family Medicine. "This paper identifies how common imposter syndrome is, and the personality traits most associated with it, which gives us an avenue to address it."

Medical students nationwide report alarming rates of depression, anxiety and burnout. Identifying and intervening to support psychological well-being in these learners is a continuing challenge, especially among first year medical students.

Dr. Rosenthal and her colleagues examined imposter syndrome, which is defined as inappropriate feelings of inadequacy among high achievers, using a validated survey tool called the Clance Imposter Phenomenon (IP) Scale. Of the 257 students who completed the survey, 87% of students who reported high levels of imposter syndrome, were more likely to show an even higher degree of imposter syndrome at the end of their first year. They also found that students' higher IP scores were associated with lower scores for self-compassion, sociability, self-esteem and higher scores on neuroticism/anxiety. Therefore, a high CIP score among entering students may be an indicator of future risk for experiencing psychological distress during medical school.

"Imposter syndrome is a malleable personality construct, and is therefore responsive to intervention," says Dr. Rosenthal, who is also the medical college's associate dean for Student Affairs. "Supportive feedback and collaborative learning, mentoring by faculty, academic support, individual counseling and group discussions with peers are all helpful. For many students, the most powerful first step in addressing and ameliorating imposter syndrome is normalizing this distorted and maladaptive self-perception through individual sessions with faculty and mentored small-group discussions with peers."

It is of interest to note that the students in this study the medical college's Class of 2020 were exposed to the traditional medical school curriculum. The following year, Jefferson introduced an innovative new curriculum, called JeffMD. Dr. Rosenthal and colleagues plan to compare the rates of imposter syndrome in students exposed to the novel curriculum. The new JeffMD curriculum emphasizes collaborative learning with a faculty mentor and a small group of students. The researchers hope, and will test whether this change in the learning environment can ameliorate feelings of imposterism.