It’s possible that I shall make an ass of myself. But in that case one can always get out of it with a little dialectic. I have, of course, so worded my proposition as to be right either way (K.Marx, Letter to F.Engels on the Indian Mutiny)
IMAGE: PRADEEP BHIDE, THE JIM AND BETTY ANN RODGERS EMINENT SCHOLAR CHAIR OF DEVELOPMENTAL NEUROSCIENCE IN THE DEPARTMENT OF BIOMEDICAL SCIENCESview more
CREDIT: FLORIDA STAET UNIVERSITY
Florida State University College of Medicine researchers have linked aspartame, an artificial sweetener found in nearly 5,000 diet foods and drinks, to anxiety-like behavior in mice.
Along with producing anxiety in the mice who consumed aspartame, the effects extended up to two generations from the males exposed to the sweetener. The study is published in the Proceedings of the National Academy of Sciences.
“What this study is showing is we need to look back at the environmental factors, because what we see today is not only what’s happening today, but what happened two generations ago and maybe even longer,” said co-author Pradeep Bhide, the Jim and Betty Ann Rodgers Eminent Scholar Chair of Developmental Neuroscience in the Department of Biomedical Sciences.
The study came about, in part, because of previous research from the Bhide Lab on the transgenerational effects of nicotine on mice. The research showed temporary, or epigenetic, changes in mice sperm cells. Unlike genetic changes (mutations), epigenetic changes are reversible and don’t change the DNA sequence; however, they can change how the body reads a DNA sequence.
“We were working on the effects of nicotine on the same type of model,” Bhide said. “The father smokes. What happened to the children?”
The U.S. Food and Drug Administration (FDA) approved aspartame as a sweetener in 1981. Today, nearly 5,000 metric tons are produced each year. When consumed, aspartame becomes aspartic acid, phenylalanine and methanol, all of which can have potent effects on the central nervous system.
Led by doctoral candidate Sara Jones, the study involved providing mice with drinking water containing aspartame at approximately 15% of the FDA-approved maximum daily human intake. The dosage, equivalent to six to eight 8-ounce cans of diet soda a day for humans, continued for 12 weeks in a study spanning four years.
Pronounced anxiety-like behavior was observed in the mice through a variety of maze tests across multiple generations descending from the aspartame-exposed males.
“It was such a robust anxiety-like trait that I don’t think any of us were anticipating we would see,” Jones said. “It was completely unexpected. Usually you see subtle changes.”
When given diazepam, a drug used to treat anxiety disorder in humans, mice in all generations ceased to show anxiety-like behavior.
Researchers are planning an additional publication from this study focused on how aspartame affected memory. Future research will identify the molecular mechanisms that influence the transmission of aspartame’s effect across generations.
Other co-authors were Department of Biomedical Sciences faculty members Deirdre McCarthy, Cynthia Vied and Gregg Stanwood, and FSU Department of Psychology Professor Chris Schatschneider.
This research was supported by the Jim and Betty Ann Rodgers Chair Fund at Florida State University and by the Bryan Robinson Foundation.
Doctoral candidate Sara Jones, lead author of research examining the effects of aspartame, defending her her doctoral dissertation on the topic.
Rising ocean temperatures are driving deterioration of kelp forests worldwide, but a University of Otago study hopes to help turn the tide and restore the valuable habitats.
Kelp forests are one of the most diverse and productive natural ecosystems on the planet, but in the past 50 to 100 years significant swaths have been lost and many of the remaining systems show a declining trajectory.
Researchers in Otago’s Coastal People: Southern Skies Centre of Research Excellence are undertaking a project into what is driving current declines of kōauau/giant kelp in Aotearoa New Zealand.
The kelp is found from the bottom of the North Island down to the subantarctic islands and is a key habitat for many culturally, recreationally, and commercially important species such as pāua and kōura (crayfish).
In a study, just published in international journal PLoS ONE, the group aimed to understand the effects of increasing temperature on the early developmental stages of the kelp.
Lead author Duong Le, PhD candidate in the Department of Marine Science, says, while increasing sea temperatures are known to be behind the decline, the particular mechanisms driving the loss are not well understood.
The researchers found higher temperatures stimulated greater spore release during the process of sporulation. However, spore settlement, germination, and germ-tube length were negatively impacted by increased temperature and significantly declined above 23.8˚C, 21.7˚C, and 19.8˚C, respectively.
“This study highlights the vulnerability of early life stages of giant kelp development and helps us better understand past changes and the future trajectory of kelp forest ecosystems in Aotearoa,” he says.
Co-author Dr Mathew Desmond, also of the Department of Marine Science, says this is the first study to measure the thermal threshold of spore and germling life stages of giant kelp.
“This information is key for making predictions of how such a valuable ecosystem engineer will perform in decades to come.
“This piece of work adds to our wider understanding of this species and aids our attempts to help protect and rebuild it.”
The researchers hope their work will motivate people to take an interest in the changes to natural environments going on around them and seek to understand what might be driving them, specifically issues around climate change and warming oceans.
*This ongoing research was funded through an MBIE Smart Ideas grant; an Otago University PhD scholarship to Duong Le; and by Otago’s Coastal People: Southern Skies Centre of Research Excellence.
Publication details:
Effect of temperature on sporulation and spore development of giant kelp (Macrocystis pyrifera)
Duong M. Le, Mathew J. Desmond, Daniel W. Pritchard, Christopher D. Hepburn
ITHACA, N.Y. - Electric cars – and their continued sales growth – are expected to have a greener, cleaner influence on air pollution and reduce human mortality in most, if not all, U.S. metropolitan areas, according to Cornell University research published inRenewable and Sustainable Energy Reviews(March 2023).
As the microscopic soot discharged from carbon-fueled cars continues to drop substantially, the research measured the potential of the large-scale use of passenger electric vehicles on air pollution and associated economic gains throughout the U.S. by 2050.
“While we enjoy the mobility that passenger vehicles provide, many of us don’t realize how bad those carbon emissions are, that come out from tailpipes, and how they’re impacting our health,” said senior author Oliver Gao, the Howard Simpson Professor of Civil and Environmental Engineering in the College of Engineering at Cornell University.
Gao and his colleagues examined data from the Environmental Protection Agency’s National Emission Inventory, the Community Multi-scale Air Quality modeling system and an associated tool, which estimates the economic value of health impacts resulting from changes in air quality – specifically ground-level fine particles (2.5 micrometers and smaller, known as PM2.5.)
With fresher air, in 27 years greater Los Angeles will have 1,163 fewer premature deaths annually, corresponding to $12.61 billion in improved economic health benefits, according to the paper. Greater New York City could see 576 fewer such deaths annually and have $6.24 billion in associated economic gains and health benefits, while Chicago could have 276 fewer deaths and gain about $3 billion in financial well-being.
In California’s San Joaquin Valley, the scientists calculated there would be 260 fewer annual deaths and a $2.82 billion economic benefit, while Dallas-Fort Worth would see 186 fewer annual deaths and $2 billion in economic and health gains, to round out the top five areas.
Global sales of electric vehicles have grown steadily, the researchers said. While electric cars sold around the world was less than 1% of market share in 2016, the share grew to 2.2% by 2018. The market share globally doubled to about 4.1% in 2020 and then to 6.6% in 2021.
In the U.S., market share of electric passenger vehicles was 4.5% in 2021, but at the city sales level, according to the paper, passenger vehicle market shares were 22% in San Francisco, 11.9% in Los Angeles, 11.7% in Seattle and 3.4% in New York City.
With carbon-fueled passenger vehicles still all around now, tailpipe emissions surround us, said Gao, a faculty fellow at the Cornell Atkinson Center for Sustainability. “It’s not like power plants, where the stacks are usually far away,” he said. “If we fully electrify transportation, we’re not only helping defeat global climate change, but we’re also helping the regional improvement of air quality.”
The benefits of electric vehicle adoption on air quality and public health are quite clear, it is also important to accelerate the implementation of this mitigation strategy, said the paper’s lead author Shuai Pan, a former Cornell post-doctoral researcher, now at Nanjing University of Information Science and Technology (NUIST), China.
“In addition to sound policies at the national level,” he said, “the successful implementation of zero-emission vehicle goals requires commitments and actions at the regional level.”
Electrifying transportation has comprehensive advantages. “We all want to win this battle against climate change and we all want to electrify transportation,” Gao said. “I hope this research can help local decision-makers to carry out real action and policy that improve the air and gain health rewards for regional residents in many ways.”
IMAGE: SOUTHER, LEFT, WORKING IN AN EMORY OAK GROVE WITH STUDENTS MEGAN QUINN, BRANDEE JOE AND TIMBERLEE CASTILLO AND WITH ANNA JACKSON, A CITIZEN OF THE YAVAPAI APACHE NATION, CENTER.view more
CREDIT: CREDIT: SIERRA BRYAN, KNAU
Assistant professor Sara Souther of Northern Arizona University’s School of Earth and Sustainability (SES) is principal investigator on a major new project focused on restoring a tree species important to the cultural heritage of tribal communities in the Southwest.
Acorns from the Emory oak tree are a critically important resource for the Western Apache Tribal Nations—including the Yavapai-Apache, Tonto Apache, San Carlos Apache and White Mountain Apache Tribal Nations in east and central Arizona—who use it both for food and for cultural and ceremonial purposes. Groves of Emory oak have been declining in health and yielding fewer acorns with each harvest for several decades due to loss of habitat, fire suppression, livestock grazing, groundwater reductions, species competition and climate change.
With $1.5 million in funding from the National Science Foundation (NSF), Souther will launch a five-year project starting in March 2023 entitled “DISES: Restoration of a southwestern cultural keystone species: Integrating socio‐ecological systems to predict resilience of traditional acorn harvest by western Apache communities.” Co-principal investigators on the multidisciplinary conservation project, representing SES and NAU’s School of Forestry as well as the departments of Biology, Sociology and Geography and Planning & Recreation, are associate professor Clare Aslan, Regents’ professor Peter Fulé, assistant professor Alark Saxena, associate teaching professor Amanda Stan, associate professor Diana Stuart, professor Andi (Andrea) Thode and associate professor Amy Whipple.
“I am extremely excited to have the resources to explore this amazing social-ecological system. For a long time, I’ve felt that wild harvest and traditional ecological practices and traditions have been viewed as niche issues within the world of conservation. It is thrilling to see this work elevated by the NSF,” Souther said.
“We are taking a holistic landscape-level approach to understand the threats to these woodlands. Emory oaks are a cultural keystone species for western Apache Tribes and the dominant oak in the Madrean oak woodlands, which cover around 80,000 km2 across the Southwest and US-Mexico borderlands,” she said. “Despite this, the Madrean oak system is understudied. In order to conserve Emory oak, we need to quickly learn a lot about this ecosystem, and in particular, we must understand what constrains population growth and viability. My work has always focused on understanding ecocultural interactions, supporting communities connected to these landscapes and conserving land and traditions. The DISES funding will support these same goals, providing the opportunity to rapidly learn about the Madrean oak woodlands as a coupled human and natural system.”
This project builds on work done through the Emory Oak Collaborative Tribal Restoration Initiative (EOCTRI), a collaborative partnership between NAU, the U.S. Forest Service and five different Apache tribes. Their goal is to restore and protect Emory oak stands to ensure the long-term persistence of Emory oak using tribal traditional ecological knowledge to guide goals and activities. Since 2018, the partners have worked together to identify and assess important Emory oak stands, complete clearances and begin implementing restoration and protection activities for several groves. With this new project, the team’s goals are to expand their knowledge of the Emory oak system, support the goals of EOCTRI—to conserve Emory oak trees and the traditional acorn harvest by Western Apache Tribes—and provide knowledge to the EOCTRI group according to the ethics of the Chi’Chil Advisory Committee. Watch this video to learn more about the EOCTRI’s efforts.
Souther’s project is also related to an initiative that was launched to better understand how to manage ecocultural resources on public lands—the Tribal Nations Botanical Research Collaborative (TNBRC), a U.S. Forest Service Citizen Science program in which volunteers collect information on traditionally used plants that have cultural, medicinal or economic values important to tribal communities. They record observations of these plants using the iNaturalist app on their cell phones. Scientists gather and analyze the data and use it to shape conservation and land management goals for increased sustainability.
Research related to Souther’s roots in rural Appalachia
“My work with the Emory oak builds on my past research on traditional use plant conservation in Appalachia,” Souther said. “I grew up in West Virginia, which has a rich heritage of harvesting wild plants for food, medicine and other essentials. It wasn’t until I went to Paraguay, as a Peace Corps volunteer, that I realized how much of this traditional knowledge had been lost in Appalachian culture. In Paraguay, small children knew the names and uses of all the plants growing in forests and fields nearby—which meant that most children had a working knowledge of hundreds of plants. Meanwhile, in West Virginia, most of this ecological knowledge was held by the elderly and was not actively passed down to youth. I could see our Appalachian culture disappearing, and for me, this ecocultural erosion was devastating. Harvest expeditions in Appalachia, whether to pick ramps (wild onions), blueberries or pawpaw (a fruit related to custard-apples), were part of the experience growing up in West Virginia and important for connecting with family and the land. More broadly, I feel that maintaining human connections to the land is key to human health and well-being and critical to inspire conservation of our wild spaces.”
Project designed to involve students from underrepresented groups
Souther is dedicated to outreach, mentorship and training to promote participation of underrepresented groups in STEM, and she is using this project as an opportunity to hire several students. Souther is also a co-PI with Amy Whipple on another project designed to increase diversity in STEM targeting post-baccalaureate training for underrepresented groups, principally Indigenous communities.
“Coming from rural Appalachia, I connect with students who may feel like outsiders in STEM fields. It is extremely important to me to support underrepresented groups as they navigate graduate school and academia. My commitment to increasing diversity in STEM fields is personal, since support from NSF and university faculty launched my career, and also practical, because I believe that the sciences will be strengthened by diverse opinions and thinkers.”
“We are recruiting four graduate students for this project and will be hiring undergraduate students as well to support field work in the summer. I encourage students to apply for these positions on my lab website.”
Souther said, “The broader impacts of this project will be to advance understanding and predictive modeling of stochastic drought events, which will likely drive ecological change in the Southwest and other arid regions. Integrating information from Native American tribal collaborators, we will contribute to diversity and inclusion in environmental resource management, ensuring that Indigenous perspectives and needs are incorporated into decision-making.”
She is also working on a two-year project funded through a $538,203 award from the National Oceanic and Atmospheric Administration entitled, “Projecting socio-ecological impacts of drought in southwestern ecosystems to prioritize restoration initiatives.” Stuart and Steven Chischilly from the Navajo Technical Institute are co-PIs on this project.
About Northern Arizona University
Founded in 1899, Northern Arizona University is a community-engaged, high-research university that delivers an exceptional student-centered experience to its nearly 28,000 students in Flagstaff, at 22 statewide campuses and online. Building on a 123-year history of distinctive excellence, NAU aims to be the nation’s preeminent engine of opportunity, vehicle of economic mobility and driver of social impact by delivering equitable postsecondary value in Arizona and beyond. NAU is committed to meeting talent with access and excellence through its impactful academic programs and enriching experiences, paving the way to a better future for the diverse students it serves and the communities they represent.
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Scientist mimic nature to make nano particle metallic snowflakes
Scientists in New Zealand and Australia working at the level of atoms created something unexpected: tiny metallic snowflakes.
IMAGE: NANO-SCALE SNOWFLAKE FROM GALLIUM SOLVENTview more
CREDIT: IMAGE: WAIPAPA TAUMATA RAU, UNIVERSITY OF AUCKLAND
Scientists in New Zealand and Australia working at the level of atoms created something unexpected: tiny metallic snowflakes. Why’s that significant? Because coaxing individual atoms to cooperate in desired ways is leading to a revolution in engineering and technology via nanomaterials (And creating snowflakes is cool.) Nanoscale structures (a nanometre is one billionth of a metre) can aid electronic manufacturing, make materials stronger yet lighter, or aid environmental clean-ups by binding to toxins.
To create metallic nanocrystals, New Zealand and Australian scientists have been experimenting with gallium, a soft, silvery metal which is used in semiconductors and, unusually, liquifies at just above room temperature. Their results were just reported in the journal Science.
Professor Nicola Gaston and research fellow Dr Steph Lambie, both of Waipapa Taumata Rau, University of Auckland, and Dr Krista Steenbergen of Te Herenga Waka, Victoria University of Wellington, collaborated with colleagues in Australia led by Professor Kourosh Kalantar-Zadeh at the University of New South Wales.
The Australian team worked in the lab with nickel, copper, zinc, tin, platinum, bismuth, silver and aluminium, growing metal crystals in a liquid solvent of gallium. Metals were dissolved in gallium at high temperatures. Once cooled, the metallic crystals emerged while the gallium remained liquid. The New Zealand team, part of the MacDiarmid Institute for Advanced Materials and Nanotechnology, a national Centre of Research Excellence, carried out simulations of molecular dynamics to explain why differently shaped crystals emerge from different metals. (The government’s Marsden Fund supported the research.)
“What we are learning is that the structure of the liquid gallium is very important,” says Gaston. “That’s novel because we usually think of liquids as lacking structure or being only randomly structured.” Interactions between the atomistic structures of the different metals and the liquid gallium cause differently shaped crystals to emerge, the scientists showed.
The crystals included cubes, rods, hexagonal plates and the zinc snowflake shapes. The six-branched symmetry of zinc, with each atom surrounded by six neighbours at equivalent distances, accounts for the snowflake design. “In contrast to top-down approaches to forming nanostructure – by cutting away material – this bottom-up approaches relies on atoms self-assembling,” says Gaston. “This is how nature makes nanoparticles, and is both less wasteful and much more precise than top-down methods.” She says the research has opened up a new, unexplored pathway for metallic nanostructures. “There’s also something very cool in creating a metallic snowflake!”
A prudent approach to health and care, incorporating the values people, patients and local communities attribute to their health and care services, is key to transforming the health and care system.
Leaders from Welsh health and care think tank the Bevan Commission, writing in the Journal of the Royal Society of Medicine, say that the range of effects regarded as valuable by patients should be taken into account. They also say that prudent planning and decision-making should include stopping low-value work, using all skills and resources to best effect, and redirecting resources to those in greatest need.
Helen Howson, Director of the Bevan Commission, said: “The COVID-19 pandemic highlighted the importance of marrying our values with value to focus on what really matters. A prudent approach to health and care aims to work co-productively with people, managing all the skills and resources we have available to us in a way that helps us to achieve the best possible outcomes for all.”
She went onto say that the health and social care system must ensure that it puts people’s needs first and not those of the system or its services.
Future investment decisions must recognise the prudence of protecting and improving health and wellbeing and population health which should be based on a values-based leadership model, write the authors. Leaders, they say, should be flexible and open to challenge and change at every level and face up to questions about how the workforce will operate and be trained in the future.
Ms Howson added: “There is a need to transform our system through our values while remaining aligned to the founding principles of the National Health Service. By incorporating the prudent principles and vision, the system in Wales will understand and tackle health inequalities as part of a whole-system, values-based approach.”
LIGHT PUBLISHING CENTER, CHANGCHUN INSTITUTE OF OPTICS, FINE MECHANICS AND PHYSICS, CAS
IMAGE: A, THE COLLIMATED GAUSSIAN SHAPED INTO HIGH QUALITY THIN ANNULAR BEAM. B, THE PRINCIPLE OF THE LONGITUDINAL FIELD GENERATION AND THE COMPARISON OF THE CONVENTIONAL FIELD AND THE LONGITUDINAL FIELD FOR MATERIALS ABLATION. C, 10 NM FEATURE GENERATED ON SAPPHIRE AND THE CROSS SECTION OF THE CROSS SECTION OF A HOLE WITH NO TAPER AND DEPTH TO WIDTH ASPECT RATIO OVER 16.view more
CREDIT: BY ZHAOQING LI, OLIVIER ALLEGRE, LIN LI
Towards the end of the 19th century, Abbe and Rayleigh formulated the principles of optical diffraction that limits the resolution of optical instruments in the far-field where the distance between the target and the optical element is far greater than the optical wavelength. These principles remained unchallenged for over a century until new developments in optical technologies opened up new avenues for breaking the diffraction limit. One such technique uses focused annular amplitude collimated laser beams with a radial polarisation, so that opposite direction plane waves propagate towards the same focal point and cause constructive interference in the optical axis, leading to a symmetrical focal spot where all-the electric fields are oriented in the longitudinal direction, parallel to the optical axis. Although a number of prior investigations attempted to demonstrate the possibility to break the optical diffraction limit by using the so-called longitudinal field, the purity of these fields has never been sufficiently high to achieve the best processing resolutions. On the one hand, the spherical aberration of a high NA lens focusing is difficult to overcome by using standard optical lenses. On the other, a high-quality annular collimated beam with a very small width and a uniform distribution is required, which is also difficult to realise by only blocking the central area of the beam. If the focused laser beam is a mixture of longitudinal and transverse fields, the processing resolution is reduced.
In a new paper published in Light: Science & Applications, a team of scientists led by Professor Lin Li and Dr Olivier Allegre from the Laser Processing Research Centre, The University of Manchester, UK, has developed a novel method to experimentally demonstrate a longitudinal femtosecond laser field (i.e., parallel to the optical axis) with an unprecedented high purity (94.7%) and its interactions with polished silicon, copper, and sapphire. A new optical setup is developed using an 800 nm wavelength femtosecond laser source and a pair of spatial light modulators (SLMs) in a double 4-f optical arrangement to tailor the laser light fields and realise high-quality and uniform beam shaping to correct the spherical aberration of the 0.95 NA objective lens. The experiments involved focusing the beam first using an aplanatic 0.75 NA lens to confirm the presence of the longitudinal fields, and then using a 0.95 NA lens to further understand the characteristics of the focused longitudinal fields and their effects on laser materials processing. A number of polarisation states, beam intensity distribution and wavefront ablation profiles were investigated and the results were compared with theoretical models of the longitudinal field. Material processing with a resolution (10 nm, i.e., l/80) well beyond the far-field diffraction limit at the infrared laser wavelength of 800 nm was demonstrated on polished sapphire in air.
Dr. Zhaoqing Li summarized the operational principle of his PhD project：
“To generate high purity longitudinal field, the laser beam needs to be shaped into a high quality annular beam. We firstly shaped the original collimated Gaussian into a perfect Gaussian beam, and then converted it to a thin annular beam, by using a spatial light modulator (SLM)”
“Before focusing the annular laser beam with radial polarisation with a 0.95 NA objective lens, the spherical aberration needs to be precisely corrected, to make sure the laser beam is focused into a same plane. We realised it by using another spatial light modulator (SLM), so we could achieve the high-quality longitudinal field, with a purity of up to 94.7%”.
“By focusing the longitudinal field on sapphire, holes with a diameter as small as 10 nm could be created, which is much smaller than the previously published results based on strong nonlinear laser materials interaction processes.”
“To verify the cross-section characteristics of these tiny holes, focused ion beam (FIB) cross-sectioning was conducted. For a 30 nm diameter hole, the depth was over 500 nm with a zero taper.”
Dr. Olivier Allegre summarized the principle of the longitudinal ablation:
“The extremely small feature size and very high depth to width aspect ratio with parallel hole walls observed in this study could indicate that the material removal mechanism induced with the longitudinal field is fundamentally different from those induced with a transverse linear polarisation. This phenomenon is rarely seen in laser materials processing at this scale with a single pulse. ”
“In the experimental results demonstrated in this paper, the electrical field is to the laser beam axis. The laser beam with the longitudinal field could behave somewhat like a particle accelerator and enable the electron (with negative charge) and ion (positive charge) to be ejected more effectively than in a standard Coulombic explosion. The very deep holes produced in our experiments show the possibility of electron acceleration and charge polarisation in the holes for material removal.”
Professor Lin Li commented: “The significance of this research is the demonstration of super-resolution materials processing with an infrared laser beam, which breaks the optical diffraction limit in the far field, while most previous approaches are either based on costly extreme ultraviolet (EUV) laser wavelengths that operate within the optical diffraction limit, or on the use of near field optics that make the working distance too close to be practically useful. The very high aspect ratio of the laser processed features points out a new material removal mechanism.”
Wearing a face mask can temporarily disrupt decision-making in some situations according to University of Queensland research.
Dr David Smerdon from UQ’s School of Economics analysed almost three million chess moves played by more than eight thousand people in 18 countries before and during the COVID-19 pandemic and found wearing a mask substantially reduced the average quality of player decisions.
“The decrease in performance was due to the annoyance caused by the masks rather than a physiological mechanism, but people adapted to the distraction over time,” Dr Smerdon said.
“The data showed masks were more likely to decrease performance in situations where there was a demanding mental task with a high working memory load.
“This is something to keep in mind for occupations in the STEM fields of science, technology, engineering and mathematics as well as other professions that demand a high level of working memory such as language interpreters, performers, waiters and teachers.”
Dr Smerdon, an Australian chess Grandmaster, said while mask mandates had helped to curb the spread of COVID-19, almost nothing was known about their impact on cognitive performance.
“At the moment there are no large studies on the impact of mask wearing on the general population,” he said.
“Chess can provide us with that insight as it requires calculation, memory, problem-solving and pattern recognition and has been used extensively in psychology, neuroscience and economics to measure changes in cognitive performance.”
Dr Smerdon’s study found that while mask wearing had a negative impact on chess performance, the effect subsided after four to six hours of playing.
“The results suggest that the effect of masks may depend on the type of task, the duration of the task and working memory load,” he said.
Dr Smerdon said understanding the impact of mask wearing on decision-making could help individuals and organisations better evaluate when and how to use them.
“For example, education policy makers may need to bear in mind the disruptive effects of masks when designing exam conditions to address concerns about student health and fairness,” he said.
IMAGE: RESEARCHERS AT CHIBA UNIVERSITY, JAPAN, PREPARED POLYACRYLONITRILE (PAN)-BASED ACTIVATED CARBON FIBERS THAT ARE CAPABLE OF REMOVING NITRATE IONS FROM THE ENVIRONMENT. A. ADSORBENT STRUCTURE AND ITS SURFACE FUNCTIONAL GROUPS. QUATERNARY NITROGEN (N-Q), INCLUDING GRAPHITIC NITROGEN, AND ALIPHATIC AMINE COULD BE EFFECTIVE FOR THE REMOVAL OF ANIONIC POLLUTANTS, SUCH AS NITRATE, PHOSPHATE, CHROMIUM, AND ARSENIC ANIONS. B. A GRAPH REPRESENTING THE INFLUENCE OF EQUILIBRIUM SOLUTION PH (PHE) ON THE AMOUNT OF NO3- ADSORPTION.view more
CREDIT: MOTOI MACHIDA FROM CHIBA UNIVERSITY, JAPAN
Nitrate ion is a common pollutant produced by municipal waste treatment systems, agricultural run-offs, and livestock waste. Although an essential component of fertilizers and necessary for growing food, nitrates can be harmful when left to circulate in our ecosystem without proper treatment. It can, for instance, lead to algal bloom in water bodies, which reduces the amount of dissolved oxygen in water, posing a threat to aquatic organisms. Nitrate ions have also been associated with blood disorders in infants and digestive cancers in adults. Hence, an easy and cost-effective way to remove nitrate ions from our ecosystem is crucial.
Over the years, researchers have tried and tested several materials that can remove nitrate ions via adsorption. A popular approach is to use adsorbent materials, such as activated carbon fibers (ACF). The porous structure of ACFs enables the introduction of a wide range of functional groups that can be chosen per the adsorption requirements. They are also easy to recover and reuse. Unfortunately, there are certain shortcomings of ACF that hinder its applications.
Prof. Motoi Machida from Chiba University, Japan, who leads the research on nitrate ion removal, sheds some light on the issues faced. “Carbonaceous materials like activated carbons are usually functionalized with negatively charged functional groups, such as carboxy, carbonyl or phenol, which show excellent adsorption performance for positively charged ions and organic pollutants but are ineffective against inorganic negatively charged ions,” he explains. “So, we wanted to develop a durable ACF-based material that can efficiently adsorb nitrate ions and retain adsorption capacity for multiple uses.”
In a recent breakthrough made available online on 10 October 2022 and published in SN Applied Sciences on 22 October 2022, Prof. Machida, along withMs. Natsuho Sato and Associate Prof. Yoshimasa Amano from Chiba University, designed sodium carbonate activated, polyacrylonitrile (PAN)-based ACF with high nitrogen content for nitrate ion removal. To increase the adsorption property of the PAN-ACF, the team activated them with sodium carbonate at 800°C. They further heat-treated the fibers at 950°C, which reduced the nitrogen content but increased the amount of quaternary nitrogen (N-Q), a positively charged functional group capable of nitrate adsorption.
Following the preparation process, the team carried out tests to analyze the nitrate ion adsorption dynamics of the material. The results showed that heat treatment increased the nitrate adsorption capacity by eliminating nitrate-repelling functional groups, such as –COOH and –COO–. The PAN-ACF material showed excellent adsorption properties, with an adsorption capacity of 0.5 mmol/g nitrate ions from water.
The team also conducted long-term degradation studies under different storage conditions to figure out the best way of storing the material for optimum reuse results. They found that keeping the ACFs in hydrochloric acid solution or under vacuum kept them stable. The adsorption capacity and degradation studies revealed that the material showed a consistent adsorption rate at a pH of 4-5, an encouraging find since 4-5 is the pH range of groundwater.
“Our new robust material can withstand treatments with boiling water, and strong acidic and basic solutions, thereby still easily regenerate with minimal loss in adsorption capacity,” adds Prof. Machida.
Overall, the new PAN-ACF presented in the study can not only treat environmental water by removing harmful nitrate ions but also help reduce the dependence on conventional plastic material-based ion exchange resins by replacing them with more environment-friendly active carbon-based ion removers.
