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    Magnetic superstructures resonate with global 6G developers

    Osaka Metropolitan University researchers observed unprecedented collective resonance motion in chiral helimagnets that allow a boost in current frequency bands.
    When will 6G be a reality? The race to realize sixth generation (6G) wireless communication systems requires the development of suitable magnetic materials. Scientists from Osaka Metropolitan University and their colleagues detected an unprecedented collective resonance at high frequencies in a magnetic superstructure called a chiral spin soliton lattice (CSL), revealing CSL-hosting chiral helimagnets as a promising material for 6G technology. The study was published in Physical Review Letters.
    Future communication technologies require expanding the frequency band from the current few Gigahertz (GHz) to over 100 GHz. Such high frequencies are not yet possible given that existing magnetic materials used in communication equipment can only resonate and absorb microwaves up to approximately 70 GHz with a practical-strength magnetic field. Addressing this gap in knowledge and technology, the research team led by Professor Yoshihiko Togawa from Osaka Metropolitan University delved into the helicoidal spin superstructure CSL. “CSL has a tunable structure in periodicity, meaning it can be continuously modulated by changing the external magnetic field strength,” explained Professor Togawa. “The CSL phonon mode, or collective resonance mode ― when the CSL’s kinks oscillate collectively around their equilibrium position ― allows frequency ranges broader than those for conventional ferromagnetic materials.” This CSL phonon mode has been understood theoretically, but never observed in experiments.
    Seeking the CSL phonon mode, the team experimented on CrNb3S6, a typical chiral magnetic crystal that hosts CSL. They first generated CSL in CrNb3S6 and then observed its resonance behavior under changing external magnetic field strengths. A specially designed microwave circuit was used to detect the magnetic resonance signals.
    The researchers observed resonance in three modes, namely the “Kittel mode,” the “asymmetric mode,” and the “multiple resonance mode.” In the Kittel mode, similar to what is observed in conventional ferromagnetic materials, the resonance frequency increases only if the magnetic field strength increases, meaning that creating the high frequencies needed for 6G would require an impractically strong magnetic field. The CSL phonon was not found in the asymmetric mode, either.
    In the multiple resonance mode, the CSL phonon was detected; in contrast to what is observed with magnetic materials currently in use, the frequency spontaneously increases when the magnetic field strength decreases. This is an unprecedented phenomenon that will possibly enable a boost to over 100 GHz with a relatively weak magnetic field — this boost is a much-needed mechanism for achieving 6G operability.
    “We succeeded in observing this resonance motion for the first time,” noted first author Dr. Yusuke Shimamoto. “Due to its excellent structural controllability, the resonance frequency can be controlled over a wide band up to the sub-terahertz band. This wideband and variable frequency characteristic exceeds 5G and is expected to be utilized in research and development of next-generation communication technologies.”
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    Scientists conceptualize a species 'stock market' to put a price tag on actions posing risks to biodiversity

    So far, science has described more than 2 million species, and millions more await discovery. While species have value in themselves, many also deliver important ecosystem services to humanity, such as insects that pollinate our crops.
    Meanwhile, as we lack a standardized system to quantify the value of different species, it is too easy to jump to the conclusion that they are practically worthless. As a result, humanity has been quick to justify actions that diminish populations and even imperil biodiversity at large.
    In a study, published in the scholarly open-science journal Research Ideas and Outcomes, a team of Estonian and Swedish scientists propose to formalize the value of all species through a conceptual species ‘stock market’ (SSM). Much like the regular stock market, the SSM is to act as a unified basis for instantaneous valuation of all items in its holdings.
    However, other aspects of the SSM would be starkly different from the regular stock market. Ownership, transactions, and trading will take new forms. Indeed, species have no owners, and ‘trade’ would not be about transfer of ownership rights among shareholders. Instead, the concept of ‘selling’ would comprise processes that erase species from some specific area — such as war, deforestation, or pollution.
    “The SSM would be able to put a price tag on such transactions, and the price could be thought of as an invoice that the seller needs to settle in some way that benefits global biodiversity,” explains the study’s lead author Prof. Urmas Kõljalg (University of Tartu, Estonia).
    Conversely, taking some action that benefits biodiversity — as estimated through individuals of species — would be akin to buying on the species stock market. Buying, too, has a price tag on it, but this price should probably be thought of in goodwill terms. Here, ‘money’ represents an investment towards increased biodiversity.
    “By rooting such actions in a unified valuation system it is hoped that goodwill actions will become increasingly difficult to dodge and dismiss,” adds Kõljalg.
    Interestingly, the SSM revolves around the notion of digital species. These are representations of described and undescribed species concluded to exist based on DNA sequences and elaborated by including all we know about their habitat, ecology, distribution, interactions with other species, and functional traits.
    For the SSM to function as described, those DNA sequences and metadata need to be sourced from global scientific and societal resources, including natural history collections, sequence databases, and life science data portals. Digital species might be managed further by incorporating data records of non-sequenced individuals, notably observations, older material in collections, and data from publications.
    The study proposes that the SSM is orchestrated by the international associations of taxonomists and economists.
    “Non-trivial complications are foreseen when implementing the SSM in practice, but we argue that the most realistic and tangible way out of the looming biodiversity crisis is to put a price tag on species and thereby a cost to actions that compromise them,” says Kõljalg.
    “No human being will make direct monetary profit out of the SSM, and yet it’s all Earth’s inhabitants — including humans — that could benefit from its pointers.”
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    Math model predicts efficacy of drug treatments for heart attacks

    Researchers used mice to develop a mathematical model of a myocardial infarction, popularly known as a heart attack.
    The new model predicts several useful new drug combinations that may one day help treat heart attacks, according to researchers at The Ohio State University.
    Typically caused by blockages in the coronary arteries — or the vessels that supply blood to the heart — these cardiovascular events are experienced by more than 800,000 Americans every year, and about 30% end up dying. But even for those who survive, the damage these attacks inflict on the muscles of the heart is permanent and can lead to dangerous inflammation in the affected areas of the heart.
    Treatment to restore blood flow to these blocked passages of the heart often includes surgery and drugs, or what’s known as reperfusion therapy. Nicolae Moise, lead author of the study and a postdoctoral researcher in biomedical engineering at Ohio State, said the study uses mathematical algorithms to assess the efficacy of the drugs used to combat the potentially lethal inflammation many patients experience in the aftermath of an attack.
    “Biology and medicine are starting to become more mathematical,” Moise said. “There’s so much data that you need to start integrating it into some kind of framework.” While Moise has worked on other mathematical models of animal hearts, he said that the framework detailed in the current paper is the most detailed schematic of myocardial infarctions in mice ever made.
    The research is published in the Journal of Theoretical Biology.
    Represented by a series of differential equations, the model Moise’s team created was made using data from previous animal studies. In medicine, differential equations are often used to monitor the growth of diseases in graph form. More

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    Next gen television and computer screens: Creating optically active polymers

    A scientist from the Faculty of Pure and Applied Sciences at the University of Tsukuba developed a method for producing electrically conductive polymers that assume a helical configuration. By using a liquid crystal as a template, he was able to produce optically active polymers that can convert light into a circular polarization. This approach may help lower the cost of smart displays.
    Walking into an electronic store these days can be an overwhelming experience if you happen to wander into the television aisle. The sizes of TVs have significantly expanded in recent years, while the prices have dropped. This is mainly due to the adoption of organic light emitting devices (OLEDs), which are carbon-based polymers that can glow at tunable optical wavelengths. These conjugated polymers, which have alternating single and double bonds, are both electrically conductive, and have colors that can be controlled by chemical doping with other molecules. Their oxidation state can also be rapidly switched using an electric voltage, which affects their coloration. However, future advancement may require new materials that can take advantage of other kinds of optical properties, such as circular polarization.
    Now, a researcher from the University of Tsukuba has introduced a technique for creating polymers locked into a helical configuration, using a sacrificial liquid crystal template. “Polymers that both have optical activity and luminescent function can emit circularly polarized light,” author Professor Hiromasa Goto says. For this process, the liquid crystal molecules were originally in a straight configuration. The addition of monomer molecules caused the liquid crystals to twist into a helical configuration. This imprints a “chirality” or handedness to the structure, making it oriented either clockwise or counterclockwise. An electric voltage was applied, which triggered polymerization of the monomers. The liquid crystal template was then removed, leaving a polymer frozen in a helical shape. By breaking the mirror symmetry, the polymer has the ability to convert linearly polarized light into a circular polarization. The furan rings in the polymer not only contribute to the electrical conductivity, they also help stabilize the helical structure. “The pi-stacking interactions between the rings allows the polymer to aggregate into a highly ordered chiral system,” Professor Goto says. The resulting polymer was tested using circular dichroism absorption spectroscopy and was found to have strong optical activity at visible wavelengths. Future applications of this process may include cheaper and more energy efficient electronic displays.
    This work was supported by the Japan Society for the Promotion of Science (JSPS), Grants-in-Aid for Scientific Research (Magnetic Properties of Magneto-Optically Active Helical Polymers, No. 20K05626).
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    Electrically conductive paints and other polymer alloys now produced easily

    Medical devices, cars, and many advanced technologies contain innumerable delicate components that are held together by electrically conductive polymers, such as polyaniline. For several decades, synthesis of polyaniline for industrial electronics applications has faced a major limitation: what solvent best facilitates synthesis? This abstract question is important for minimizing the cost and complexity of polyaniline production and facilitating useful properties such as shaping. The ability to use a range of cheap, low-boiling-point solvents would greatly assist versatile polymer processing modes such as inkjet printing, but had remained elusive until now.
    In a study recently published in Polymer-Plastics Technology and Materials, researchers from the University of Tsukuba and collaborating partners have synthesized polyaniline in various common solvents. This improved ability to synthesize and process polyaniline will greatly simplify production and lower manufacturing costs.
    “Polyaniline is an extremely versatile polymer in routine and advanced technologies, but restrictions on which solvents can be used for synthesis have long hindered this versatility,” explains Professor Hiromasa Goto, senior author. “Our discovery of how to facilitate polymerization in diverse solvents will be useful in basic research and industrial applications.”
    The researchers produced polyaniline from aniline sulfate in a single step when they added a small quantity of iodine to the reaction mixture. Many solvents were compatible with this procedure, including nontoxic ethanol as well as dichloromethane. Extensive instrumental characterizations demonstrated that the polyaniline produced by this method exhibited the crystallinity and electrical properties as if it had been prepared by conventional methods.
    “A particularly exciting result is the ease of preparing industrially useful polymer alloys, such as blends with polystyrene or cellulose derivatives,” says Professor Goto. “Electrically conductive paint, advanced rubber blends, and other materials are now straightforward to prepare, which we expect will facilitate product development in diverse fields.”
    What is it about the added iodine that facilitates polyaniline production? The researchers propose that iodine is an electron-acceptor dopant that facilitates production of localized polarons, which is critical to the subsequent polymerization by radical chain reactions.
    The results of this study will help make polyaniline more compatible with inkjet printing and other useful processing technologies, and thus simplify production of printed circuit boards and other common components of modern electronics. By focusing on the rather abstract topic of solvent compatibility, many routine and advanced technologies will be easier to make at lower cost.
    This work was supported by the Japan Society for the Promotion of Science (JSPS, Grants-in-Aid for Scientific Research (KAKENHI) [20K05626].
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    Training virtually can reduce psychosocial stress and anxiety

    Previous research has described how virtual training produces acute cognitive and neural benefits. Building on those results, a new study suggests that a similar virtual training can also reduce psychosocial stress and anxiety.
    Researchers from Tohoku University’s Smart-Aging Research Center (IDAC) published their findings in the International Journal of Environmental Research and Public Health on May 23, 2022.
    Physical exercise benefits our overall well-being. But for some — such as neurological patients, people suffering from cardiovascular disease, and hospitalized patients — physical exercise is not feasible, or even too dangerous. However, similar effects may be brought about using Immersive Virtual Reality (IVR).
    Despite initially designed for entertainment, IVR has attracted interest from the academic community because of its potential use for clinical purposes, since it allows the user to experience a virtual world through a virtual body.
    In the researchers’ previous study, they found that looking at a moving virtual body displayed in first-person perspective induces physiological changes. Heart rates increased/decreased coherently with the virtual movements, even though the young participants remained still. Consequently, acute cognitive and neural benefits occurred, just like after real physical activity.
    In a followup study, the same benefits were also found on healthy elderly subjects after 20-minute sessions occurring twice a week for six weeks.
    In the current study, the researchers explored the effect on stress, adding another level to the beneficial effects of virtual training. Young healthy subjects, while sitting still, experienced a virtual training displayed from the first-person perspective, creating the illusion of ownership over movements.
    The avatar ran at 6.4 km/h for 30 minutes. Before and after the virtual training, the researchers induced and assessed the psychosocial stress response by measuring the salivary alpha-amylase — a crucial biomarker indicating the levels of neuroendocrine stress. Similarly, they distributed a subjective questionnaire for anxiety.
    The results showed a decreased psychosocial stress response and lower levels of anxiety after the virtual training, comparable to what happens after real exercise.
    “Psychosocial stress represents the stress experienced in frequent social situations such as social judgment, rejection, and when our performances get evaluated,” says Professor Dalila Burin, who developed the study. “While a moderate amount of exposure to stress might be beneficial, repeated and increased exposure can be detrimental to our health. This kind of virtual training represents a new frontier, especially in countries like Japan, where high performance demands and an aging population exist.”
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    Western wildfires’ health risks extend across the country

    After a relaxing day at the Jersey Shore last July, Jessica Reeder and her son and daughter headed back home to Philadelphia. As they crested a bridge from New Jersey into Pennsylvania, they were greeted with a hazy, yellow-gray sky. It reminded Reeder of the smoky skies she saw growing up in Southern California on days when fires burned in the dry canyons.

    Smelling smoke and worried about her asthma and her kids, Reeder flipped the switch to recirculate the air inside the car instead of drawing from the outside. At home, the family closed all the windows and turned their air purifiers on high.

    The smoke had traveled from fires raging on the other side of the continent, in the western United States and Canada. Although air quality in Philadelphia didn’t come close to the record-bad air quality that some western cities experienced, it was bad enough to trigger air quality warnings — and not just for people with asthma or heart problems.

    Most large U.S. wildfires occur in the West. But the smoke doesn’t stay there. It travels eastward, affecting communities hundreds to thousands of kilometers away from the fires. In fact, the majority of asthma-related deaths and emergency room visits attributed to fire smoke in the United States occur in eastern cities, according to a study in the September 2021 GeoHealth.

    Smoke poured into the eastern United States and Canada from wildfires in the West on July 21, 2021 (darker red is denser smoke). Residents of eastern cities received code orange and code red warnings that air quality was unhealthy.Joshua Stevens/NASA Earth Observatory

    The big problem is fine particulate matter, tiny particles also known as PM2.5. These bits of ash, gases and other detritus suspended in smoke are no more than 2.5 micrometers wide, small enough to lodge in the lungs and cause permanent damage. PM2.5 exacerbates respiratory and cardiovascular problems and can lead to premature death. The particles can also cause asthma and other chronic conditions in otherwise healthy adults and children.

    Over the last few decades, U.S. clean air regulations have cut down on particulate matter from industrial pollution, so the air has been getting cleaner, especially in the populous eastern cities. But the regulations don’t address particulate matter from wildfire smoke, which recent studies show is chemically different from industrial air pollution, potentially more hazardous to humans and increasing significantly.

    So far, a lot of the research on how wildfire PM2.5 can make people sick has been based on people living or working near fires in the West. Now, researchers are turning their attention to how PM2.5 from smoke affects the big population centers in the East, far from the wildfires. One thing is clear: With the intensity and frequency of wildfires increasing due to climate change (SN: 12/19/20 & 1/2/21, p. 32), people across North America need to be concerned about the health impacts, says Katelyn O’Dell, an atmospheric scientist at George Washington University in Washington, D.C.

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    Bad air travels

    Air pollution regulations limit PM2.5 from exhaust-emitting cars and trucks and fossil fuel–burning factories and power plants. These regulations have done “a really good job” reducing anthropogenic air pollution in the last couple of decades, says Rosana Aguilera, an environmental scientist at the Scripps Institution of Oceanography in La Jolla, Calif. In the United States, concentrations of six of the most common air pollutants have dropped by 78 percent since the Clean Air Act of 1970, according to the U.S. Environmental Protection Agency. PM2.5 concentrations have come down as well — at least until recently.

    Western wildfires, which are growing more frequent, more severe and larger, are erasing some of the gains made in reducing industrial pollution, says Rebecca Buchholz, an atmospheric chemist at the National Center for Atmospheric Research in Boulder, Colo.

    Fires in the Pacific Northwest are “driving an upward trend” in particulate matter air pollution, Buchholz and colleagues wrote April 19 in Nature Communications. Such smoke pollution peaks in August when fires in the region tend to spike and the atmosphere’s ability to clean itself through, say, rain, is limited. This spike of late-summer air pollution is new, Buchholz says. It’s especially noticeable since 2012.

    New York City, visible through hazy skies in September 2020, and many places in the East have seen some of the worst air quality in decades due to fires burning in the U.S. West and in Canada. Such fires are increasing in intensity and frequency.Gary Hershorn/Getty Images plus

    And, as Reeder and her family experienced last year, transported wildfire pollution is causing substantial particulate matter spikes in the central United States and northeastern North America, Buchholz and colleagues found. Pacific Northwest wildfires thus “have the potential to impact surface air quality, even at large distances downwind of the wildfires,” the team wrote, putting some 23 million people in the central United States and 72 million in northeastern North America at increased risk of health impacts from the imported wildfire smoke.

    How far and where PM2.5 travels depends on weather patterns and how high wildfire smoke reaches — the stronger the fire, the longer it can last and the farther smoke can go, and thus the farther particulate matter can reach. Last year, far-away wildfires created unhealthy air quality conditions in locations from the Great Plains to New York City and Washington, D.C.

    New York City saw some of its worst air quality in two decades. Philadelphia had two “code red” days — meaning air quality was unhealthy for all — because of the U.S. West and Canadian fires. In 2019, 2020 and 2021, those fires pushed PM2.5 to unhealthy levels in much of Minnesota. In fact, a 2018 study showed that wildfire smoke plumes now waft above Minnesota for eight to 12 days per month between June and September.

    Human impacts

    Smoke in the West is already having a tangible effect on human health in the East, says O’Dell, lead author of the 2021 GeoHealth study.

    Reviewing smoke and health data from 2006 to 2018, O’Dell and colleagues found that more people visit emergency rooms and are hospitalized in the East than in the West from asthma problems attributable to smoke PM2.5. Asthma-related ER visits and hospitalizations were higher east of the Rockies in 11 of the 13 years.

    Over the study period, an average of 74 percent of asthma-related deaths and 75 percent of asthma ER visits and hospitalizations attributable to smoke occurred east of the Rockies. Of the estimated 6,300 excess deaths from asthma complications due to smoke PM2.5 that occurred annually over the study period, more than 4,600 were in the East.

    Smoke affects so many more people in the East primarily because more people live there, O’Dell notes. Her team defined “West” as west of the Rockies, with a population of 64 million, and “East” as east of the Rockies, home to 226 million people. In the West, smoke PM2.5 causes a higher portion of regional asthma deaths. In the East, it’s a lower portion of the total population, but a far higher total number of people affected.

    “We may be already seeing the consequences of these fires on the health of residents who live hundreds or even thousands of miles downwind,” Buchholz said in a press release.

    Vulnerable youth

    “Asthma is a very widespread, common health condition,” says Yang Liu, an environmental scientist at Emory University in Atlanta. In the United States, about 25 million people have asthma, or 8 percent of adults and 7 percent of children, according to the U.S. Centers for Disease Control and Prevention.

    Fine particulate matter can spark asthma attacks, but it can also be a danger to people without the condition. Children are especially vulnerable primarily because of physiology. Children breathe faster so they end up taking in more particulate matter, plus their lungs are smaller so more of their lung surface is likely to be damaged when they breathe in particulate matter. And their lungs are still developing, says Jennifer Stowell, an environmental epidemiologist at Boston University School of Public Health.

    Stowell led a study, reported in the January Environmental Research Letters, estimating how much wildfire smoke will exacerbate asthma attacks in the West. Stowell, Liu and colleagues estimate that, in the 2050s, there will be an additional 155,000 asthma-related ER visits and hospitalizations per wildfire season in the West just from smoke PM2.5. The biggest concern, Stowell says, is for children and younger adults.

    Aguilera, of Scripps, and her colleagues found associations between wildfire-specific PM2.5 and pediatric respiratory-related ER and urgent care visits. In San Diego County from 2011 to 2017, wildfire-specific PM2.5 was 10 times as harmful to respiratory health in children 5 and younger as ambient PM2.5, the researchers reported in 2021 in Pediatrics. In fact, the same increase in levels of PM2.5 from smoke versus ambient sources caused a 26 percent higher rate of ER or urgent care visits. The researchers didn’t note whether the children had preexisting asthma.

    And even when a wildfire increased PM2.5 by a small amount, respiratory ER and urgent care visits in kids 12 and under increased, Aguilera and colleagues reported in 2020 in the Annals of the American Thoracic Society. “Even relatively smaller wildfires can still generate quite an impact on the pediatric population,” Aguilera says. “And really, any amount of PM or air pollution is harmful.”

    Studies of nonhuman primates have also shown permanent effects of smoke on the young — results researchers expect would also apply to humans, given genetic similarities. In 2008, a group of infant rhesus macaques at the California National Primate Research Center at the University of California, Davis was exposed to high PM2.5 levels from a series of devastating wildfires in Northern California. Researchers have been comparing those monkeys with macaques born a year later that weren’t exposed to smoke.

    At the California National Primate Research Center, rhesus macaques that were exposed to wildfire smoke early in life have immune disorders, nervous system changes and weakened lungs. © 2014 Kathy West/California National Primate Research Center/UC Davis

    At around age 3, macaques exposed to smoke displayed immune disorders and reduced lung capacity, lung function and lung volume, says Hong Ji, a molecular biologist at UC Davis and the primate center who wasn’t involved with this study. The lungs look like they had fibrosis, Ji says. “Early life smoke exposure … changed the trajectory of lung development,” and it doesn’t appear to be reversible, she says.

    The monkeys exposed to wildfire PM2.5 also have important changes to how their DNA works, Ji and colleagues reported in the January Environment International. Exposure to wildfire smoke in infancy can cause life-altering, long-term changes to the monkeys’ nervous and immune systems, as well as brain development, Ji says. Even worse, she says, the DNA changes are the type that can be passed down and may result in generational damage.

    Even macaques born after in utero exposure to wildfire smoke can suffer cognitive, immune and hormone problems, primate center researchers reported April 1 in Nature Communications.

    Now, Ji and colleagues have teamed with Rebecca Schmidt, a molecular epidemiologist at UC Davis who’s leading a study on the effects of wildfire smoke exposure on pregnant women and young children. This research group, as well as other teams, is also looking into whether PM2.5 is causing genetic changes to babies exposed to smoke in utero, Ji says. The more results gathered on the effects of wildfire PM2.5 on babies and children — and even in pregnancy — the more dangerous we realize it is, Ji says.

    Chemical differences

    Particulate matter changes as it travels through the atmosphere, both in volume and in chemistry. Some PM2.5 is emitted directly from fires, and some is born from chemicals and trace gases emitted from fires that get chemically processed in the atmosphere, Buchholz says. Reactions that happen in the smoke plume, combined with sunlight, can create even more PM2.5 downwind of the fires. How these particulates change chemically — through interactions between the atmosphere and the particulate matter, and between fire pollution and human pollution — and what that means for human health “is a really active area of research right now,” she says. “It’s super complicated.”

    Epidemiological and atmospheric chemistry studies indicate that wildfire PM2.5 is more hazardous to human health than ambient PM2.5, says Stowell, the Boston epidemiologist. One such study compared particulate matter from Amazonian fires with urban sources such as vehicle exhaust in Atlanta. Nga Lee Ng, an atmospheric chemist at Georgia Tech, and colleagues found that smoke particulate matter is more toxic than urban particulate matter, “inducing about five times higher cellular oxidative stress,” Ng says. Oxidative stress damages cells and DNA in the body.

    In addition, as smoke travels through the atmosphere and ages, it seems to become even more toxic, Ng says. Reactions between the particulate matter and sunlight and atmospheric gases change the particulate matter’s chemical and physical properties, rendering it even more potentially harmful. So, even though particulate matter dissipates over time and distance, “the health effects per gram are greater,” says Daniel Jaffe, an atmospheric chemist at the University of Washington Bothell.

    That means that the studies of health effects near wildfires in the West may not represent the full story of how smoke from distant fires affects people in the East.

    Liu, at Emory, hopes to see the U.S. government revisit policies related to what PM2.5 levels are dangerous, since they’re based on ambient and not wildfire-related PM2.5. In March, an EPA advisory panel recommended just that. In a letter to the agency, the Clean Air Scientific Advisory Committee wrote: “Regarding the annual PM2.5 standard, all CASAC members agree that the current level of the annual standard is not sufficiently protective of public health and should be lowered.” The committee added, “There is substantial epidemiologic evidence from both morbidity and mortality studies that the current standard is not adequately protective.”

    Local communities throughout the country need to determine when to close schools or at least keep kids inside, Liu says, as well as when to advise people to close windows and turn on air purifiers. Good masks — N95 and KN95 — can help too (yes, masks that block viruses can also block particulate matter).

    City, county and state governments also need to prepare the health care system to respond to increased asthma issues, Liu says. Some states are starting to respond. In 2017, for example, the Minnesota Pollution Control Agency increased its air quality monitoring stations around the state from two to 18. The agency is also working with the National Weather Service, the Minnesota Department of Health and the Minnesota Department of Transportation to better communicate air quality warnings.

    Minnesota, after experiencing a rise in smoky summer days, has added extra air quality monitoring stations to improve local forecasts.Minnesota Pollution Control Agency

    In the meantime, much more research is needed into the human health implications of increasing wildfire smoke, Buchholz says, as well as the chemical interactions in the atmosphere, how climate is changing fires, how fires change year after year, and how they impact the atmosphere, not to mention how different trees, buildings and other fuels affect particulate matter.

    “Wildfires are perhaps one of the most visible ways that [climate change] is linked to health,” Stowell says. And the reality is, she says, “we’re going to see it remain as bad or worse for a while.” More

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    Researchers change the game when it comes to activity tracking

    The creation of high-resolution extrusion printing — think 3D printing but with ink that conducts electricity — has enabled UBC researchers to explore the potential of wearable human motion devices.
    Wearable technology — smartwatches, heart monitors, sleep aid devices, even step counters — have become part of everyday life. And researchers with UBC Okanagan’s Nanomaterials and Polymer Nanocomposites Laboratory, have created even smaller, lighter and highly-accurate sensors that can be integrated into clothing and equipment.
    In collaboration with Drexel University and the University of Toronto, the UBCO research team is exploring a high-resolution extrusion printing approach to develop tiny devices with dual functionality — electromagnetic interference (EMI) shields and a body motion sensor.
    Tiny and lightweight, these EMI shields can have applications in the health care, aerospace and automotive industries, explains Dr. Mohammad Arjmand, Assistant Professor and Canada Research Chair in Advanced Materials and Polymer Engineering at UBC Okanagan’s School of Engineering.
    Using a two-dimensional inorganic nanomaterial called MXene, alongside a conductive polymer, Dr. Arjmand’s team has customized a conductive ink with a number of properties that make it easier to adapt into wearable technologies.
    “Advanced or smart materials that provide electrical conductivity and flexibility are highly sought-after,” he says. “Extrusion printing of these conductive materials will allow for macro-scale patterning, meaning we can produce different shapes or geometries, and the product will have outstanding architecture flexibility.”
    Currently, manufacturing technologies of these functional materials are mostly limited to laminated and unsophisticated structures that don’t enable the integration of monitoring technologies, explains doctoral student Ahmadreza Ghaffarkhah.
    “These printed structures can be seeded with micro-cracks to develop highly sensitive sensors. Tiny cracks in their structures are used to track small vibrations in their surroundings,” says Ghaffarkhah. “These vibrations can monitor a multitude of human activities, including breathing, facial movements, talking as well as the contraction and relaxation of a muscle.”
    By going back to the drawing board, the UBCO researchers were able to address a major challenge encountered by extrusion printing. Previously, the technology didn’t allow for high-enough printing resolution, so it was difficult to manufacture highly precise structures.
    “Compared to conventional manufacturing technologies, extrusion printing offers customization, reduction in materials waste, and rapid production, while opening up numerous opportunities for wearable and smart electronics,” explains Dr. Arjmand. “As extrusion printing techniques improve, it is opening the door to many unique innovations.”
    The researchers continue to investigate additional applications for extrusion printing inks that go beyond EMI shields and wearable electronics.
    The research was published in Carbon, with financial support from a Natural Sciences and Engineering Research Council of Canada Alliance Grant and Zentek Limited. More