Existing research shows that natural sounds, like birdsong, can lower blood pressure, heart, and respiratory rates, as well as self-reported stress and anxiety. Conversely, anthropogenic soundscapes, like traffic or aircraft noise, are hypothesized to have negative effects on human health and wellbeing in a variety of ways.

In the new study, 68 student volunteers listened to three 3-minute soundscapes: a nature soundscape recorded at sunrise in West Sussex, U.K., the same soundscape combined with 20 mile per hour road traffic sounds, and the same soundscape with 40 mile per hour traffic sounds. General mood and anxiety were assessed before and after the soundscapes using self-reported scales.

The study found that listening to a natural soundscape reduced self-reported stress and anxiety levels, and also enhanced mood recovery after a stressor. However, the benefits of improved mood associated with the natural soundscape was limited when traffic sounds were included. The natural soundscape alone was associated with the lowest levels of stress and anxiety, with the highest levels reported after the soundscape that included 40 mile per hour traffic.

The authors conclude that reducing traffic speed in urban areas might influence human health and wellbeing not only through its safety impacts, but also through its effect on natural soundscapes.

The authors add: “Our study shows that listening to natural soundscapes can reduce stress and anxiety, and that anthropogenic sounds such as traffic noise can mask potential positive impacts. Reducing traffic speeds in cities is therefore an important step towards more people experiencing the positive effects of nature on their health and wellbeing.”

Almost 10 billion people are expected to inhabit Earth by 2050, so agricultural production will become increasingly critical to feeding the growing population. Over the past six decades, much of the growth in food production has stemmed from technological advances, including the widespread development and use of better crop varieties. But some studies have suggested that the growth in production has leveled off, raising concerns about future food availability, especially in the low- and middle-income countries with the highest population growth.

In the new study, the researchers developed standardized measures for production and yield for 144 crops, covering 98 percent of global agricultural land. These measures allow scientists and policymakers to compare agricultural productivity across different countries and regions. The researchers found that there has been no discernable slowdown in the global growth of crop yields during the last six decades — any observed slowdown in specific crops, regions or countries has been offset by gains in others. Their findings show that yields grew annually at a rate equivalent to about 33 kg of wheat per hectare.

While the study’s findings are reassuring from a global food supply perspective, the researchers caution that sustainable food production and the affordability of food will continue to be challenges to global food security. They emphasize that these concerns are particularly relevant in the face of intensifying climate change and increased demand for food due to population and income growth.

The authors add: “Utilizing a comprehensive caloric-based index of production and yield for 144 crops, covering 98% of global agricultural land and food output, this paper reveals that, on an aggregate level, global yield growth — a vital indicator of agricultural productivity — has not slowed over the past six decades. This steady growth equates to an annual increase of approximately 33 kilograms of wheat per hectare, highlighting continued productivity gains worldwide.”

The study, published in the journal Science Advances, shows that the oceans not only capture and redistribute the sun’s heat, but produce gases that make particles with immediate climatic effects, for example through the brightening of clouds that reflect this heat.

It broadens the climatic impact of marine sulfur because it adds a new compound, methanethiol, that had previously gone unnoticed. Researchers only detected the gas recently, because it used to be notoriously hard to measure and earlier work focussed on warmer oceans, whereas the polar oceans are the emission hotspots.

The research was led by a team of scientists from the Institute of Marine Sciences (ICM-CSIC) and the Blas Cabrera Institute of Physical Chemistry (IQF-CSIC) in Spain. They included Dr Charel Wohl, previously at ICM-CSIC and now at the University of East Anglia (UEA) in the UK.

Their findings represent a major advance on one of the most groundbreaking theories proposed 40 years ago about the role of the ocean in regulating the Earth’s climate.

This suggested that microscopic plankton living on the surface of the seas produce sulfur in the form of a gas, dimethyl sulphide, that once in the atmosphere, oxidizes and forms small particles called aerosols.

Aerosols reflect part of the solar radiation back into space and therefore reduce the heat retained by the Earth. Their cooling effect is magnified when they become involved in making clouds, with an effect opposite to, but of the same magnitude as, that of the well-known warming greenhouse gases, such as carbon dioxide or methane.

The researchers argue that this new work improves our understanding of how the climate of the planet is regulated by adding a previously overlooked component and illustrates the crucial importance of sulfur aerosols. They also highlight the magnitude of the impact of human activity on the climate and that the planet will continue to warm if no action is taken.

Dr Wohl, of UEA’s Centre for Ocean and Atmospheric Sciences and one of the lead authors, said: “This is the climatic element with the greatest cooling capacity, but also the least understood. We knew methanethiol was coming out of the ocean, but we had no idea about how much and where. We also did not know it had such an impact on climate.

“Climate models have greatly overestimated the solar radiation actually reaching the Southern Ocean, largely because they are not capable of correctly simulating clouds. The work done here partially closes the longstanding knowledge gap between models and observations.”

With this discovery, scientists can now represent the climate more accurately in models that are used to make predictions of +1.5 ºC or +2 ºC warming, a huge contribution to policy making.

“Until now we thought that the oceans emitted sulfur into the atmosphere only in the form of dimethyl sulphide, a residue of plankton that is mainly responsible for the evocative smell of shellfish,” said Dr Martí Galí, a researcher at the ICM-CSIC and another of the main study authors.

Dr Wohl added: “Today, thanks to the evolution of measurement techniques, we know that plankton also emit methanethiol, and we have found a way to quantify, on a global scale, where, when and in what quantity this emission occurs.

“Knowing the emissions of this compound will help us to more accurately represent clouds over the Southern Ocean and calculate more realistically their cooling effect.”

The researchers gathered all the available measurements of methanethiol in seawater, added those they had made in the Southern Ocean and the Mediterranean coast, and statistically related them to seawater temperature, obtained from satellites.

This allowed them to conclude that, annually and on a global average, methanethiol increases known marine sulfur emissions by 25%.

“It may not seem like much, but methanethiol is more efficient at oxidising and forming aerosols than dimethyl sulfide and, therefore, its climate impact is magnified,” said co-lead Dr Julián Villamayor, a researcher at IQF-CSIC.

The team also incorporated the marine emissions of methanethiol into a state-of-the-art climate model to assess their effects on the planet’s radiation balance.

It showed the impacts are much more visible in the Southern Hemisphere, where there is more ocean and less human activity, and therefore the presence of sulfur from the burning of fossil fuels is lower.

The work was supported by funding from organisations including the European Research Council and Spanish Ministry of Science and Innovation.

Led by Xing Wang, a professor of bioengineering and of chemistry at the U. of I., the researchers describe their advance in the journal Science Robotics.

Inspired by the gripping power of the human hand and bird claws, the researchers designed the NanoGripper with four bendable fingers and a palm, all in one nanostructure folded from a single piece of DNA. Each finger has three joints, like a human finger, and the angle and degree of bending are determined by the design on the DNA scaffold.

“We wanted to make a soft material, nanoscale robot with grabbing functions that never have been seen before, to interact with cells, viruses and other molecules for biomedical applications,” Wang said. “We are using DNA for its structural properties. It is strong, flexible and programmable. Yet even in the DNA origami field, this is novel in terms of the design principle. We fold one long strand of DNA back and forth to make all of the elements, both the static and moving pieces, in one step.”

The fingers contain regions called DNA aptamers that are specially programmed to bind to molecular targets — the spike protein of the virus that causes COVID-19, for this first application — and trigger the fingers to bend to wrap around the target. On the opposite side, where the wrist would be, the NanoGripper can attach to a surface or other larger complex for biomedical applications such as sensing or drug delivery.

To create a sensor to detect the COVID-19 virus, Wang’s team partnered with a group led by Illinois electrical and computer engineering professor Brian Cunningham, who specializes in biosensing. They coupled the NanoGripper with a photonic crystal sensor platform to create a rapid, 30-minute COVID-19 test matching the sensitivity of the gold-standard qPCR molecular tests used by hospitals, which are more accurate than at-home tests but take much longer.

“Our test is very fast and simple since we detect the intact virus directly,” Cunningham said. “When the virus is held in the NanoGripper’s hand, a fluorescent molecule is triggered to release light when illuminated by an LED or laser. When a large number of fluorescent molecules are concentrated upon a single virus, it becomes bright enough in our detection system to count each virus individually.”

In addition to diagnostics, the NanoGripper could have applications in preventive medicine by blocking viruses from entering and infecting cells, Wang said. The researchers found that when NanoGrippers were added to cell cultures that were then exposed to COVID-19, multiple grippers would wrap around the outside of the viruses. This blocked the viral spike proteins from interacting with receptors on the cells’ surface, preventing infection.

“It would be very difficult to apply it after a person is infected, but there’s a way we could use it as a preventive therapeutic,” Wang said. “We could make an anti-viral nasal spray compound. The nose is the hot spot for respiratory viruses, like COVID or influenza. A nasal spray with the NanoGripper could prevent inhaled viruses from interacting with the cells in the nose.”

The NanoGripper could easily be engineered to target other viruses, such as influenza, HIV or hepatitis B, Wang said. In addition, Wang envisions using the NaoGripper for targeted drug delivery. For example, the fingers could be programmed to identify specific cancer markers, and grippers could carry cancer-fighting treatments directly to the target cells.

“This approach has bigger potential than the few examples we demonstrated in this work,” Wang said. “There are some adjustments we would have to make with the 3D structure, the stability and the targeting aptamers or nanobodies, but we’ve developed several techniques to do this in the lab. Of course it would require a lot of testing, but the potential applications for cancer treatment and the sensitivity achieved for diagnostic applications showcase the power of soft nanorobotics.”

The National Institutes of Health and the National Science Foundation supported this work. Wang and Cunningham are affiliated with the Carl R. Woese Institute for Genomic Biology and the Holonyak Micro and Nanotechnology Lab at the U. of I.

Editor’s note: To reach Xing Wang, email @illinois.edu” title=”mailto:xingw@illinois.edu”>xingw@illinois.edu.

The paper “Bioinspired designer DNA NanoGripper for virus sensing and potential inhibition” is available from @aaas.org” title=”mailto:robopak@aaas.org”>robopak@aaas.org. DOI: 10.1126/scirobotic

This work was supported in part by NIH grants R21EB031310, R44DE030852 and R21AI166898.

Species most likely to go extinct sooner were endemic to islands, lacked the ability to fly, had larger bodies and sharply angled wings, and occupied ecologically specific niches, according to research published this month.

While some of these findings mirror previous research on extinct birds, they are the first to correlate bird traits with the timing of extinctions, said lead author Kyle Kittelberger, a graduate student in the School of Biological Sciences.

“I’ve been very interested in extinctions and understanding the species that we’ve lost and trying to get a sense of how we can use the past to better inform the present and future,” said Kittelberger, who is completing his dissertation on how the bodies and wings of certain species of migratory songbirds have changed in response to climate change.

His team’s analysis tapped into BirdBase, a dataset of ecological traits for the world’s 11,600+ bird species compiled by U biology professor Ça?an ?ekercio?lu and the Biodiversity and Conservation Ecology Lab at the U. The team simultaneously analyzed a broad range of biogeographical, ecological and life history traits previously associated with extinction and extinction risk for bird species that have gone extinct as well as those that lack recent confirmed sightings and have therefore disappeared.

“Importantly, we examine biological correlates of bird extinctions through the lens of when birds went extinct, providing a novel extinction timing element that helps better inform why birds with certain traits disappeared when they did,” Kittelberger wrote in a series of posts on X. By identifying traits that most predispose birds to extinction, the findings can help guide conservation efforts of hundreds of species that are at peril.

“One of the strengths of the approach that we use is we compared all of these traits simultaneously against each other, whereas a lot of previous studies in the literature just look at traits in isolation.”

While only around 2% of the world’s bird species have gone extinct since 1500, the year Kittelberger’s analysis begins, even more had already disappeared by then. Before 1500, however, there is not as reliable a record of the birds that went extinct and data on their traits and characteristics.

This timing coincides with the rise of scientific observation, resulting in a systematic documentation of plant and animal life. It is also the time when European exploration took off, leading to the disruption of ecosystems around the globe as a result of colonization and introduced species.

Today, 1,314 bird species are at risk of extinction, according to the IUCN Red List of Threatened Species, or about 12% of the total.

Many species, such as the ‘Akikiki (Oreomystis bairdi), endemic to the Hawaiian island of Kauai, are so rare that they are functionally extinct. Kittelberger photographed the pictured ‘Akikiki, also called Kauai’s creeper, in the Alaka’i Wilderness Preserve in 2022, when it was believed around 70 or so remained in the wild; today, only one individual remains.

The proportion of 216 bird species globally extinct or likely lost since 1500 that were endemic to a region, found solely on islands, and were either flightless or partially flightless, as well as the breakdown of species by primary habitat or diet.

As with many other Hawaiian bird species, the main threat to the ‘Akikiki comes in the form of introduced species, principally malaria-carrying mosquitoes and habitat-wrecking livestock, according to Hawaii’s Division of Forestry and Wildlife.

The single most critical trait associated with extinction is insularity, those species endemic to islands. Other traits that appear to increase extinction risk, such as body size, wing shape and ecological specialization, are also associated with island insularity.

Pacific islands are home to a vast array of endemic species, many of which are now on the IUCN list. No archipelago has seen more loss of avian biodiversity than Hawaii, which accounts for 34 post-1500 extinctions, according to the study.

The bird family that experienced the most extinctions is Rallidae, or rails, which are globally distributed medium-sized semi-amphibious bird species. This family lost 26 members, while the entire line of the Mohoidae family, small nectar-sipping songbirds commonly known as Hawaiian honeyeaters, is completely gone (the only bird family to go fully extinct in modern times). The family’s last member, the Kauai O’o (Moho braccatus), was last observed in 1987.

The finding that did surprise Kittelberger’s team was the correlation of wing shape to extinction. They found that bird species with a larger hand-wing index, that is more pointed wings, were more likely to have vanished earlier. Since pointier wings indicate stronger flying and dispersal abilities, the team predicted such birds would be better equipped to respond to environmental pressures than those with rounder wings.

Yet birds with rounder wings, those with smaller hand-wing ratios, proved to be more resilient.

“It likely ties with the fact that a lot of these birds that went extinct were on islands. For these species or their ancestors to have arrived at these islands to begin with, they would’ve needed the ability to fly across large, open distances. So a lot of these birds on islands have, not necessarily longer, but more pointed wings,” Kittelberger said. “Think of a swift or a swallow or a bird like an albatross that flies over the ocean. They have really pointy wings that allow them to fly really well, whereas birds in dense tropical rainforests are not flying these large distances, so they have rounded wings because they’re just moving in their local habitat patches.”

Ecological specialists, as opposed to generalists, face great challenges when their specific ecological niche is altered, so they tend to be less able to respond and adapt to disturbances, like invasive species or disruption of a food source.

In other findings, the study concluded more than 87% were endemic to islands; nearly two-thirds inhabited forests; 45% ate primarily insects and other invertebrates; and 20% were completely or partially flightless. Finally, species with big bodies were overly represented on the extinct list.

“Heavier birds have been more likely to be targeted for hunting, with several well-known examples of birds being hunted to extinction in part for food, including the Dodo, Great Auk (Pinguinus impennis), and Spectacled Cormorant (Urile perspicillatus),” the study said. “Body mass has also been linked with a species’ inhabitance of islands, as island birds tend to be larger than mainland species.” Of the 43 species whose average body weight exceeded 500 grams, or 1.1 pounds, three-quarters were endemic to an island.

The decade of the 1890s saw the highest number on extinctions, with 21 recorded. The 1980s was another bad decade for bird loss with 20 species, including the Kauai O’o. This latter decade “is noteworthy since focused and targeted conservation efforts were already underway globally before and during this period,” the study said. “Though the rate of extinction declined in the subsequent decades, the number of globally threatened species has only increased.”

The study, “Correlates of avian extinction timing around the world since 1500 CE,” was published Nov. 7 in the journal Avian Research. The research team included Colby J. Tanner, Amy N. Buxton, Amira Prewett and Ça?an ?ekercio?lu. Support for this research came from the University of Utah’s Graduate Research Fellowship.

CTE is a neurodegenerative disease associated with repeated head injuries, often seen in athletes and military personnel, that can lead to mood changes and dementia.

“This appears to be a case where together these risk factors add up to a greater risk for aggression than they each do on their own, where people with CTE and a family history of mental illness are much more likely to have aggressive behavior than those with just CTE or just the family history,” said study author Jesse Mez, MD, MS, of Boston University Chobanian & Avedisian School of Medicine and a member of the American Academy of Neurology.

The study involved 845 men who were exposed to repetitive head impacts through contact sports or military service. A total of 329 of them played professional football. All donated their brains to research after their death, which was at an average age of 60. Of the total group, 589, or 70%, had CTE and 383, or 45%, had a family history of mental illness.

Researchers interviewed family members or spouses of the participants about their aggressive behavior. They were also asked whether the participants’ parents, siblings or children were ever diagnosed with major depression, bipolar disorder, anxiety, post-traumatic stress disorder, obsessive-compulsive disorder or other mood or psychiatric disorders. If any family member had a diagnosis, the participant was considered to have a family history of mental illness.

Researchers then divided participants into four groups: 256 people, or 30%, with CTE and a family history of mental illness; 333 people, or 40%, with CTE and without a family history of mental illness; 127 people, or 15%, without CTE and with a family history of mental illness; and 129 people, or 15%, without CTE and without a family history of mental illness.

Researchers asked family members about the participants’ aggressive behavior, such as whether they had severe arguments with others or got in physical fights, where scores ranged from zero to 44. They found that during adulthood people with CTE and a family history of mental illness had an average score of 19 compared to people with CTE without a family history of mental illness who had an average score of 17.

“This relationship was most striking for participants who died between 40 and 59 years old,” Mez added.

After adjusting for other factors, such as total years playing contact sports and military history, researchers found that those who died between 40 and 59 years old who had CTE and a family history of mental illness scored an average of 0.64 standard deviations higher on a scale measuring aggression when compared to those with CTE, but without a family history of mental illness. For people who did not have CTE, having a family history of mental illness did not increase their risk for aggressive behavior.

“The link between a family history of mental illness and aggression may be through a shared genetic background and also through shared environment and common behaviors, such as childhood experiences with family members,” said Mez. “Identifying people who are more likely to show symptoms of aggression based on family history of mental illness would give us a way to predict the consequences of CTE and identify who may benefit most from treatment options.”

A limitation of the study was that the study relied on past information from family members and spouses who may not have remembered information accurately.

The study was funded by the National Institutes of Health, Department of Veterans Affairs and the Nick and Lynn Buoniconti Foundation.