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)
Wednesday, December 18, 2024
How to print a car: High-performance multi-material 3D printing techniques
Tohoku University
image:
Full-scale prototype of a topologically optimized automotive suspension tower manufactured via L-PBF.
Researchers at Tohoku University's Institute for Materials Research and New Industry Creation Hatchery Center have made a breakthrough in a multi-material 3D printing technique, demonstrating the process for creating a lightweight yet durable automobile part.
The process of metal 3D printing involves building objects by depositing metals layer by layer, using heat to bind them together. The precision of 3D printing allows for the production of unique, highly customizable shapes that often create less wasteful byproducts than traditional manufacturing methods. "Multi-material structures" which strategically combine different materials for optimal performance of a component can also be created via 3D printing. For example, steel automobile parts can be made more lightweight by combining them with aluminum. Due to these benefits, mastering such 3D printing techniques is garnering considerable attention from researchers.
However, this technique does come with some challenges.
"Multi-materials are a hot topic in the field of additive manufacturing due to its process flexibility," explains Associate Professor Kenta Yamanaka (Tohoku University), "However, a major challenge in practical implementation is that for certain metal combinations, such as steel and aluminum, brittle intermetallic compounds can be formed at the dissimilar metal interfaces. So, while the material is now lighter, it ends up being more brittle."
The goal of this study was to produce a steel-aluminum alloy that was lightweight but did not compromise on strength. To do so, the research team used Laser Powder Bed Fusion (L-PBF), one of the primary metal 3D printing technologies that employs a laser to selectively melt metal powders. They discovered that increasing the scan speed of the laser significantly suppresses the formation of brittle intermetallic compounds (such as Al5Fe2 and Al13Fe4). They proposed that this higher scanning speed leads to something called non-equilibrium solidification, which minimizes solute partitioning that result in weak points in the material. The resulting product they created consequently demonstrated strong bonding interfaces.
"In other words, you can't just slap two metals together and expect them to stick without a plan," says Specially Appointed Assistant Professor Seungkyun Yim (Tohoku University),"We had to fully understand the in-situ alloying mechanism first."
Based on this achievement, they successfully prototyped the world's first full-scale automotive multi-material component (suspension tower) with a tailored geometry. The research group intends to apply these findings to other metal combinations where similar issues with bonding need improvement, which will allow for more broad applications.
The results were published in Additive Manufacturing on November 19, 2024.
Steel/Al alloy interfaces obtained using L-PBF at different scan speeds.
Some people can’t imagine a dog barking or a police siren. Songs can’t get stuck in their heads. They have no inner voices.
‘Anauralia’ was proposed in 2021 by scientists from Waipapa Taumata Rau, University of Auckland to describe the little-known condition of a silent mind.
Now, as their investigations into the phenomenon continue, the University will host a global conference on sounds imagined in the mind, an event intended not just for scientists but also philosophers, musicians, poets and writers. ‘Mind’s Ear and Inner Voice’ will run from 14-16 April in Auckland.
“Scientists are fascinated by how the brain makes – or doesn’t make – imaginary sounds such as the inner voice,” says Professor Tony Lambert, of the School of Psychology. “But for writers, musicians and poets, it can be a key part of the creative process, so they have insights to share, too.”
Charles Dickens said he heard his characters’ voices; Alice Walker, too. Some readers conjure up characters’ voices in their minds.
For University of Auckland student Sang Hyun Kim, who has a silent mind, the idea that other people are hearing imaginary voices can seem “freaky”, and he’ll be fascinated to see what research turns up about auditory imagery.
The conference hopes to include personal accounts from individuals who experience anauralia and hyperauralia, the experience of extremely vivid auditory imagery.
Some people say they can recreate a symphony in great detail in their minds. Others report weaker auditory imagery, and a small number report none. In New Zealand, it’s estimated close to 1 percent of people experience anauralia, which is often accompanied by aphantasia, a lack of visual imagination. It seems there’s no downside to a silent mind; on the contrary, recent work suggests there may be an upside, involving improved attention.
The notion of a musician experiencing anauralia seems perplexing – how could you perform that role without being able to summon up sounds in your head?
“I don’t understand this either,” says Lambert. He surmises that the minds of such musicians may contain representations of music without the sensory qualities, akin to the difference between hearing music and music represented as a score.
“Overall, auditory imagery has attracted far less research attention than visual imagery,” says Lambert. “Our conference is unique in focusing on these issues from a strongly inter-disciplinary perspective.”
Lambert’s heightened interest in the area came after meeting Adam Zeman, the scientist who coined the term aphantasia, and after graduate students in the University’s PSYCH 721 Consciousness & Cognition paper noticed that scientific literature focused on visual imagery and largely ignored auditory imagery.
“This got me thinking about the absence of auditory imagery. Are there people who don’t imagine voices, music or other sounds? If so, how common is this? What are the psychological implications of experiencing a silent inner world?
“We now have good answers to the first two questions,” he says. “The last question is a much larger one, but I believe we have made strong progress.”
The research underway in the University’s Anauralia Lab, supported by a grant from the Marsden Fund, includes a neuroimaging study combining high-density EEG, functional magnetic resonance imaging and electromyography of activity in muscles used for speech.
The line-up of keynote speakers at the conference from around the world includes experts on hearing voices – auditory verbal hallucinations – and in a field called cognitive literary studies.
Method of Research
News article
Subject of Research
People
Air pollution linked to increased hospital admissions for mental/physical illness
Stricter environmental restrictions needed to curb impact in Scotland, conclude researchers
BMJ Group
Cumulative exposure to air pollution over several years is linked to a heightened risk of admission to hospital for mental/behavioural and physical illness, finds Scottish research published in the open access journal BMJ Open.
Stricter environmental restrictions are needed to curb the impact on secondary care, conclude the researchers.
Previously published research on the health effects of long term exposure to ambient air pollution has tended to emphasise deaths rather than hospital admissions, and physical, rather than mental, ill health, suggest the researchers.
In a bid to plug this knowledge gap, the researchers drew on individual level data from the Scottish Longitudinal Study, which represents 5% of the Scottish population and includes demographic information from linked censuses.
In all, 202,237 people aged 17 and above were included in the analysis. Their health and hospital admissions for all causes; cardiovascular, respiratory, or infectious diseases; and mental illness/behaviour disorders were tracked from Public Health Scotland data and linked to levels of 4 key pollutants for each of the years between 2002 and 2017 inclusive.
The 4 pollutants from road traffic and industry comprised: nitrogen dioxide (NO2); sulphur dioxide (SO2); particulate matter diameter of at least 10 μm (PM10); and small particulate matter of 2.5 μm or less (PM2.5) per 1 km2 in each person’s residential postcode.
Fluctuations in pollutant levels were observed across the study period, with higher levels recorded in 2002–04. Over the entire period 2002–17 average levels of NO2, SO2, PM10 and PM2.5 were 12, 2, just over 11, and just over 7 μg/m3, respectively.
The average annual levels for NO2, PM10 and PM2.5 were lower than the 2005 World Health Organization (WHO) guidelines, but the levels of NO2 and PM2.5 were higher than the most recent 2021 WHO guidelines.
Average cumulative exposure to air pollution was strongly associated with higher rates of hospital admissions.
Higher cumulative exposure to NO2, PM10, and PM2.5 was associated with a higher incidence of hospital admissions for all causes, and for cardiovascular, respiratory, and infectious diseases before accounting for residential area.
When fully adjusted for cumulative exposure across time, the incidence rate for respiratory disease hospital admissions rose by just over 4% and just over 1%, respectively, for every 1 μg/m3 increase in PM2.5 and NO2 pollutants.
SO2 was mainly associated with hospital admissions for respiratory disease while NO2 was associated with a higher number of hospital admissions for mental illness/behavioural disorders.
This is an observational study, and as such, no firm conclusions about cause and effect can be drawn.
And the researchers acknowledge that although they accounted for demographics, such as age, sex, ethnicity and education level, they weren’t able to account for other potentially influential factors, such as lifestyle, weight (BMI), noise pollution or the absence of green spaces.
Exposure to ambient air pollution was assessed yearly rather than monthly or daily, so masking seasonal variations, while residential postcode had to serve as a proxy for personal exposure to air pollution.
Nevertheless, the findings echo those of previously published research, say the researchers, who suggest: “Policies and interventions on air pollution through stricter environmental regulations, long term planning, and the shifting towards renewable energy could eventually help ease the hospital care burden in Scotland in the long term.”
The continue: “Specifically, policies aimed at making the zero emission zones (ie small areas where only zero emission vehicles, pedestrians and bikes are permitted) more abundant in Scotland, especially in the central belt of Scotland where busy and more polluted cities such as Glasgow and Edinburgh are located, would improve the air quality and in turn lower the hospital care burden in those cities.”
Long term exposure to ambient air pollution and hospital admission burden in Scotland: 16 year prospective population cohort study
Article Publication Date
17-Dec-2024
Wildfire surges in East, Southeast US fueled by new trees and shrubs
Woody vegetation has increased by 37% over the last 30 years in the eastern United States, fueling the rise in large wildfires. Texas and the Appalachian Mountains took the biggest hits
American Geophysical Union
WASHINGTON — The eastern U.S. has more trees and shrubs than three decades ago. This growth, driven by processes such as tree and understory infilling in unmanaged forests, is helping fuel wildfires, contributing to changing fire regimes in the eastern half of the country, according to a new study.
Some parts of the eastern and southeastern United States have experienced a tenfold increase in the frequency of large wildfires over the last forty years, with Texas and the Appalachians seeing the largest increase. However, the Northeast lacked a tie between woody plant growth and large wildfires.
Wildfires thrive on woody vegetation such as trees and shrubs. The new analysis of wildfire and vegetation data shows that the eastern U.S. has seen a 37% increase in woody cover over the last 30 years. In some regions, high levels of woody cover are linked directly to a higher risk of large wildfires over the same period.
The research “is helping us narrow in on regional drivers and focus our efforts to preemptively get ahead of the growing wildfire problem here in the eastern U.S.,” said Victoria Donovan, a landscape ecologist at the University of Florida who was the senior author on the study.
The study was published in Geophysical Research Letters, an open-access AGU journal that publishes high-impact, short-format reports with immediate implications spanning all Earth and space sciences.
Research has shown that woody cover growing in new places or thickening within forests is directly linked to increased wildfire risk in western and central parts of the country. But whether this is true out East has yet to be explored.
To test this, Donovan and her graduate student Michaella Ivey collected data on all wildfires between 1991 and 2021 that were at least 200 hectares — around 500 football fields — or larger in eastern states. They then looked where trees and shrubs were growing in the eastern U.S over the same period. To determine if woody cover influenced wildfire risk, the researchers compared the amount of woody cover within wildfire perimeters to what would be expected if wildfires were distributed at random.
The analysis revealed a strong link between woody cover and large wildfire occurrence — but only in some parts of the country. Across the eastern temperate forest, a region that makes up nearly half of the United States, each 1% increase in woody cover led to an overall 3.9% increase in the odds of a wildfire the next year. The link between woody cover and wildfire risk was strongest in eastern Texas and in and around the Appalachian Mountains.
However, the researchers found no link between woody cover and wildfire risk in the Northeast and across some parts of the Mississippi River valley. This finding “prompts all sorts of questions about what other factors are influencing the system,” Ivey said.
Cooler and wetter conditions in the Northeast, and to some extent the Mississippi River valley, may create conditions less conducive to wildfire. However, many Northeastern ecoregions could not be included in the study due to a low number of wildfires that were large enough to meet the study’s size requirements. Wildfires in these areas may stay small because of agricultural fragmentation, the researchers said.
Because woody vegetation wasn’t tied to wildfire increase consistently throughout the study area, climate change, human actions, or a combination of the two could be more important for wildfires than vegetation in some places. But overall, the research suggests that reducing fuels is a good tactic for reducing wildfire risk in the east, Donovan said.
More prescribed fires may be necessary in southern states as climate change is expected to make the southeast drier, and potentially more prone to wildfires, the researchers caution. This research shows a path forward for states and individuals to help reduce wildfire risk in the future.
“Using fuel management to reduce wildfire risk is a lot more actionable than changing the climate pattern in the short term,” Donovan said, “though addressing climate change will likely be crucial for reducing wildfire risk in the east in the long term.”
Notes for Journalists: This study was published in Geophysical Research Letters, an open-access AGU journal. Neither this press release nor the study is under embargo. View and download a pdf of the study.
Paper title: Woody Cover Fuels Large Wildfire Risk in the Eastern US
Authors:
Michaella A. Ivey, Carissa L. Wonkka, Noah C. Weidig, and Victoria M. Donovan (corresponding author), West Florida Research and Education Center, School of Forest, Fisheries and Geomatic Sciences, Institute of Food and Agricultural Sciences, University of Florida, Milton, FL, USA
AGU (www.agu.org) is a global community supporting more than half a million advocates and professionals in Earth and space sciences. Through broad and inclusive partnerships, AGU aims to advance discovery and solution science that accelerate knowledge and create solutions that are ethical, unbiased and respectful of communities and their values. Our programs include serving as a scholarly publisher, convening virtual and in-person events and providing career support. We live our values in everything we do, such as our net zero energy renovated building in Washington, D.C. and our Ethics and Equity Center, which fosters a diverse and inclusive geoscience community to ensure responsible conduct.
Research uncovers high extinction risk for many Amazonian tree species
Wiley
Among tree species in the Ecuadorian Amazon, investigators at the Universidad de las Américas, in Ecuador, found that 14% are critically endangered and 47% are endangered. The Plants, People, Planet study indicates that trees with smaller fruits face the greatest threats due to declines of specific animal species that disperse them.
The findings reveal that the extinction risk for endemic trees is associated not only with extrinsic factors such as deforestation but also with complex relationships with other living organisms in their environment.
“Thus, our results highlight the importance of incorporating meaningful ecological traits in extinction risk estimates, such as those related to reproduction and life history strategies,” said co–corresponding author María-José Endara, PhD.
Results of this research also call into question the effectiveness of conservation strategies in formally protected areas. "For example, we found that some endemic tree species populations are experiencing high levels of threat by deforestation inside the Yasuní National Park, the biggest and most iconic protected area in the Ecuadorian Amazon,” said lead author Juan Ernesto Guevara-Andino, PhD.
Additional Information NOTE: The information contained in this release is protected by copyright. Please include journal attribution in all coverage. For more information or to obtain a PDF of any study, please contact: Sara Henning-Stout, newsroom@wiley.com.
About the Journal Plants, People, Planet publishes innovative research at the interface between plants, society, and the planet. Owned by the New Phytologist Foundation, we aim to publish studies that generate societal impact and address global issues with plant-focused solutions.
About Wiley Wiley is one of the world’s largest publishers and a trusted leader in research and learning. Our industry-leading content, services, platforms, and knowledge networks are tailored to meet the evolving needs of our customers and partners, including researchers, students, instructors, professionals, institutions, and corporations. We empower knowledge-seekers to transform today’s biggest obstacles into tomorrow’s brightest opportunities. For more than two centuries, Wiley has been delivering on its timeless mission to unlock human potential. Visit us at Wiley.com. Follow us on Facebook, X, LinkedIn and Instagram.
It’s well established that urban tree cover provides numerous environmental and psychological benefits to city dwellers. Urban trees may also bolster education outcomes and their loss could disproportionately affect students from low-income families, according to new research by University of Utah social scientists.
Economics professor Alberto Garcia looked at changes in school attendance and standardized test scores at schools in the Chicago metropolitan region over the decade after a non-native beetle called the emerald ash borer appeared in North America, eventually killing millions of ash trees along the streets and yards of Midwestern cities. His results are both alarming and insightful, revealing a complex interplay between environmental degradation and social inequities.
Linking tree loss to education
The study analyzes how the loss of tree cover influenced education outcomes in the Chicago metropolitan region, which was hit hard by the infestation. Ash had been the region’s most common non-invasive tree species, accounting for 18% of its street trees, or about 85,000 trees. Between 2010 and 2020 Chicago lost half its standing ash, with the remaining half already dead or in decline, according to the Morton Arboretum.
The study tracked changes in student performance on a standardized test administered to 3rd- through 8th-graders in Illinois, from 2003 to 2012.
“We found that test scores in areas with ash borer infestations were reduced after the onset of those infestations relative to unaffected areas that were similar,” Garcia said.
“We also looked at heterogeneity in the income distribution, and we found that schools with more low-income students were less likely to experience infestations. These neighborhoods have less tree cover, so there is less likelihood that ash borer is going to establish,” he continued. “We don't think that the low-income students in unaffected areas are impacted, but the low-income students at these impacted schools seem to be affected more than better-off students at these same schools.”
The results were reported this month in the journal Global Environmental Change. The study was co-authored by ecologist Michelle Lee, who recently joined the School of Environment, Society & Sustainability as a professor in the Utah’s College of Social & Behavioral Science after completing a postdoctoral fellowship at Penn State.
Prior research shows students in neighborhoods with greater tree cover see better test scores. A recent study by U sociologists and geographers, for example, demonstrated how low-income Utah neighborhoods have less tree canopy near their schools. Meanwhile, schools with greater tree cover had fewer students testing below proficient on year-end math and language arts exams.
Generally speaking, better education outcomes could simply be a function of these leafy neighborhoods’ higher incomes, Garcia noted.
“Our study is trying to come a little closer to establishing a causal link,” Garcia said. “We used this natural experiment of the emerald ash borer beetle being introduced and then idiosyncratically spreading around the different neighborhoods in the Chicago metropolitan area.”
To conduct the study, Garcia and Lee built a novel dataset, combining satellite imagery with Illinois’ standardized testing data and emerald ash borer survey efforts.
“We got kind of lucky that the state of Illinois was administering this standardized test in that same window when the ash borer first arrived in the area,” Garcia explained. “Every school in Illinois was taking the same test, so we had consistent data across schools and through time.”
Disparate impacts on students
Instead of merely reaffirming the tree cover-test score correlation, Garcia and Lee were able to track changes in school attendance and scores on standardized tests as the beetle infestation ran its course, laying waste to Chicago’s ash trees over the span of a decade.
The study identified a 1.22% reduction in the number of students meeting or exceeding Illinois' standardized testing benchmarks in areas hit by the ash borer. This seemingly modest drop carries significant implications when scaled across the entire student population.
“We found that schools with more low-income students were less likely to experience infestations because these neighborhoods have less tree cover,” Garcia noted. “But the low-income students at wealthier schools, where infestations were more common, seemed to bear the brunt of the impacts.”
Speculating on the mechanisms driving these effects, Garcia noted loss of tree cover could exacerbate urban heat islands, increase air pollution, and diminish the psychological and physiological benefits that greenery provides.
“Some possible explanations are just that those students don't have the same resources to go home and recover from, for example, extreme temperatures or pollution-induced headaches the same way that higher-income students at the same schools might have,” Garcia said.
Low-income students may also spend more time outdoors in their neighborhoods or remain longer near the school, increasing their exposure to degraded environmental conditions. Conversely, wealthier students might commute from more distant areas or have access to climate-controlled environments that mitigate these impacts.
Environmental justice implications
The findings highlight how environmental changes disproportionately affect vulnerable populations. While low-income neighborhoods were less likely to lose tree cover, low-income students—particularly those attending wealthier schools—suffered setbacks when infestations occurred.
“It’s not just about access to environmental amenities,” Garcia said. “It’s about understanding how their absence can create inequities that ripple through critical aspects of life, like education.”
The study underscores the importance of urban forestry initiatives and invasive species management. Efforts to maintain and restore tree cover could play a vital role in mitigating environmental and social disparities. Garcia’s work also opens the door for further exploration into how ecosystem changes shape human outcomes, particularly in urban settings where environmental inequities are stark.
Unequally distributed education impacts of ecosystem degradation: Evidence from an invasive species
How did the COVID-19 pandemic and lockdown affect the identity of trans and gender diverse youth?
Wiley
Research published in the British Journal of Developmental Psychology indicates that the COVID-19 pandemic and lockdown had largely positive impacts on gender identity development in trans and gender diverse youth.
For the study, 295 transgender and gender diverse U.S. youth, ages 13–22 years, were asked the open-ended question “How has the COVID pandemic changed or affected your own understanding of your gender identity?”
Responses revealed several themes. The most prevalent was “time for identity development,” suggesting that the pandemic and lockdown created space and time to explore and resolve their gender identity.
“The lockdown period of the pandemic gave many people the space and time to figure out who they are and what is important to them, which for many of our participants, included their gender identity,” said corresponding author Sydney Hainsworth, who was a PhD student at the University of Arizona while conducting this research and is now a postdoctoral fellow at the University of Minnesota.
NOTE: The information contained in this release is protected by copyright. Please include journal attribution in all coverage. For more information or to obtain a PDF of any study, please contact: Sara Henning-Stout, newsroom@wiley.com.
About the Journal The British Journal of Developmental Psychology is an international journal covering all aspects of psychological development across the lifespan. We publish research in biological, social, motor, perceptual, cognitive, language, neural, clinical, personality, social, and emotional development as well as atypical development. We welcome original empirical research, novel theoretical reviews, methodological papers, and systematic reviews. The journal is committed to open science and encourages research and theory relevant to underrepresented populations.
About Wiley Wiley is one of the world’s largest publishers and a trusted leader in research and learning. Our industry-leading content, services, platforms, and knowledge networks are tailored to meet the evolving needs of our customers and partners, including researchers, students, instructors, professionals, institutions, and corporations. We empower knowledge-seekers to transform today’s biggest obstacles into tomorrow’s brightest opportunities. For more than two centuries, Wiley has been delivering on its timeless mission to unlock human potential. Visit us at Wiley.com. Follow us on Facebook, X, LinkedIn and Instagram.
