Electrons from Earth may be forming water on the Moon

A team of researchers, led by a University of Hawai'i (UH) at Manoa planetary scientist, discovered that high energy electrons in Earth's plasma sheet are contributing to weathering processes on the Moon's surface and, importantly, the electrons may have aided the formation of water on the lunar surface. The study was published today in Nature Astronomy.

Understanding the concentrations and distributions of water on the Moon is critical to understanding its formation and evolution, and to providing water resources for future human exploration. The new discovery may also help explain the origin of the water ice previously discovered in the lunar permanently shaded regions.

Due to Earth's magnetism, there is a force field surrounding the planet, referred to as the magnetosphere, that protects Earth from space weathering and damaging radiation from the Sun. Solar wind pushes the magnetosphere and reshapes it, making a long tail on the night side. The plasma sheet within this magnetotail is a region consisting of high energy electrons and ions that may be sourced from Earth and the solar wind.

Previously, scientists mostly focused on the role of high energy ions on the space weathering of the Moon and other airless bodies. Solar wind, which is composed of high energy particles such as protons, bombards the lunar surface and is thought to be one of the primary ways in which water has been formed on the Moon.

Building on his previous work that showed oxygen in Earth's magnetotail is rusting iron in the Moon's polar regions, Shuai Li, assistant researcher in the UH Manoa School of Ocean and Earth Science and Technology (SOEST), was interested in investigating the changes in surface weathering as the Moon passes through Earth's magnetotail, an area that almost completely shields the Moon from solar wind but not the Sun's light photons.

"This provides a natural laboratory for studying the formation processes of lunar surface water," said Li. "When the Moon is outside of the magnetotail, the lunar surface is bombarded with solar wind. Inside the magnetotail, there are almost no solar wind protons and water formation was expected to drop to nearly zero."

Li and co-authors analyzed the remote sensing data that were collected by the Moon Mineralogy Mapper instrument onboard India's Chandrayaan 1 mission between 2008 and 2009. Specifically they assessed the changes in water formation as the Moon traversed through Earth's magnetotail, which includes the plasma sheet.

"To my surprise, the remote sensing observations showed that the water formation in Earth's magnetotail is almost identical to the time when the Moon was outside of the Earth's magnetotail," said Li. "This indicates that, in the magnetotail, there may be additional formation processes or new sources of water not directly associated with the implantation of solar wind protons. In particular, radiation by high energy electrons exhibits similar effects as the solar wind protons."

"Altogether, this finding and my previous findings of rusty lunar poles indicate that the mother Earth is strongly tied with its Moon in many unrecognized aspects," said Li.

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Earth's stability and ability to support civilization at risk: Six of nine planetary boundaries exceeded

A new study updates the planetary boundary framework and shows human activities are increasingly impacting the planet and, thereby, increasing the risk of triggering dramatic changes in overall Earth conditions.

For over 3 billion years, the interaction between life (represented by the planetary boundary, Biosphere Integrity) and climate have controlled the overall environmental conditions on Earth. Human activities, for example replacing nature with other land uses, changing the amount of water in rivers and in soil, the introduction of synthetic chemicals to the open environment, and the emission of greenhouse gases to the atmosphere all influence these interactions.

Respecting and maintaining interactions in the Earth system so that they remain similar to those that have controlled Earth conditions over the past ~12,000 years are critical for ensuring human activities do not trigger dramatic changes in Earth condition -- changes that likely would decrease the Earth's ability to support modern civilizations.

The nine "planetary boundaries" represent components of the global environment that regulate that stability and liveability of the planet for people. The degree of breaching of the safe boundary levels is caused by human-driven activities impacting the components. The planetary boundaries framework applies the newest scientific understanding of the functioning of the Earth system to identify a "safe operating space" for humanity by proposing limits for the extent to which human activities can be allowed to impact critical processes without risk of potentially triggering irreversible changes in the Earth conditions that support us.

For the first time, metrics for all boundaries are presented. Six of the boundaries are found to be transgressed, and transgression is increasing for all boundaries except the degradation of the Earth's ozone layer. A global focus on climate is not enough. Development of Earth system models that accurately reproduce interactions between boundaries, especially Climate and Biosphere Integrity, is an urgent priority.

The study, published in Science Advances, represents the third update of the framework carried out by twenty-nine scientists from eight different countries.

The Earth's "blood pressure" is too high

The trend of increasing transgression of the boundaries is worrying explains Katherine Richardson, professor at Globe Institute, Leader of the Sustainability Science Centre at the University of Copenhagen, and leader of the study:

"Crossing six boundaries in itself does not necessarily imply a disaster will ensue but it is a clear warning signal. We can regard it as we do our own blood pressure. A BP over 120/80 is not a guarantee of a heart attack but it increases the risk of one. Therefore, we try to bring it down. For our own -- and our children's -- sakes we need to reduce the pressure on these six planetary boundaries."

An important conclusion of the study is that more focus is needed on interactions between the boundaries:

"Focus on human-caused climate change is not enough if we want to protect the earth system from irreversible harm," says Johan Rockström, Director of the Potsdam Institute for Climate Impact Research (PIK), and original proposer of the framework in 2009.

"Next to climate change, integrity of the biosphere is the second pillar of stability of our planet. Our research shows that mitigating global warming and saving a functional biosphere for the future have to go hand in hand," co-author Wolfgang Lucht, Head of PIK's department of Earth System Analysis, stresses.

Use of biomass affects biodiversity

The need to respect the Land Use Change boundary puts focus on the increasing global use of biomass as an alternative for coal, oil, and gas. Biomass is the product of photosynthesis, the process where plants convert the sun's energy to energy that can be used by other living organisms and, thus, supplies the energy that supports biodiversity.

"Our study shows that humans are appropriating the equivalent of ~30 % of the energy that was available to support biodiversity before the Industrial Revolution," says Richardson.

"Surely, the removal of so much of the energy that otherwise would have been available to nature must be a driver of biodiversity loss. Therefore, we propose the adoption of Human Appropriation of Net Primary Production (HANPP), i.e., biomass use, as one of two metrics when assessing human impacts on biodiversity."

Better Earth system models needed

"A world that develops within science defined boundaries is the only way to navigate our current situation with rising, potentially catastrophic risks, at the planetary scale. We already recognise this on Climate, where the Paris agreement has adopted the climate planetary boundary of holding the 1.5°C limit. Similarly, the world has accepted the planetary boundary on biodiversity, when decided at the 2022 Montreal-Kunming COP15, to halt and reverse biodiversity loss on land and in the ocean," says Johan Rockström and continues:

"Our study shows, however, that this is by far not enough. The Planetary Boundaries science provides a 'guide for action' if we truly want to secure prosperity and equity for all on Earth, and this goes well beyond climate only, requiring novel Earth system modelling and analysis, and systematic efforts to protect, recover and rebuild planetary resilience."

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'Night owls' more likely than 'early birds' to develop diabetes

Investigators found evening 'chronotype,' or going to bed late and waking up late, was associated with a 19 percent increased risk of diabetes after accounting for lifestyle factors

A new study has an important message for people who consider themselves night owls. Investigators from Brigham and Women's Hospital, a founding member of the Mass General Brigham healthcare system, found that people with later sleep and wake times had less healthy lifestyles and were at greater risk of developing diabetes than those with early-bird sleep habits. Their results are published in the Annals of Internal Medicine.

"Chronotype, or circadian preference, refers to a person's preferred timing of sleep and waking and is partly genetically determined so it may be difficult to change," said corresponding author Tianyi Huang, MSc, ScD, an associate epidemiologist in the Brigham's Channing Division of Network Medicine. "People who think they are 'night owls' may need to pay more attention to their lifestyle because their evening chronotype may add increased risk for type 2 diabetes."

The researchers previously found that people with more irregular sleep schedules are at higher risk of developing diabetes and cardiovascular disease and that people with evening chronotypes are more likely to have irregular sleep patterns. For this study, they wanted to understand the relationship between chronotype and diabetes risk and looked at the role of lifestyle factors as well.

The team analyzed data from 63,676 female nurses from the Nurses' Health Study II collected from 2009-2017 and included self-reported chronotype (the extent to which participants perceived themselves to be an evening person or a morning person), diet quality, weight and body mass index, sleep timing, smoking behaviors, alcohol use, physical activity, and family history of diabetes. The team determined diabetes status from the participants' self-reports and medical records.

The Nurses' Health Study II, a joint effort between the Brigham's Channing Division of Network Medicine and Harvard T.H. Chan School of Public Health, is among the largest investigations into risk factors for major chronic diseases in women. One of the study's strengths is its regular follow-up of study participants and repeated assessment of health and lifestyle factors.

Approximately 11 percent of participants reported having a 'definite evening' chronotype and about 35 percent reported having 'definite morning' chronotype. The remaining population, around half, were labeled as 'intermediate,' meaning they either identified as being neither a morning nor evening type or as being only slightly more one than the other.

The evening chronotype was associated with a 72 percent increased risk for diabetes before accounting for lifestyle factors. After accounting for lifestyle factors, evening chronotype was associated with a 19 percent increased risk of diabetes. Among those in the study with the healthiest lifestyles, only 6 percent had evening chronotypes. Among those with the unhealthiest lifestyles 25 percent were evening chronotypes.

Those with evening chronotypes were found to be more likely to drink alcohol in higher quantities, have a low-quality food diet, get less hours of sleep per night, currently smoke, and have weight, BMI, and physical activity rates in the unhealthy range.

"When we controlled for unhealthy lifestyle behaviors, the strong association between chronotype and diabetes risk was reduced but still remained, which means that lifestyle factors explain a notable proportion of this association," said first author Sina Kianersi, DVM, PhD, a postdoctoral research fellow in the Brigham's Channing Division of Network Medicine.

They also found the association between evening chronotype and diabetes risk only in those nurses who worked day shifts and not those who worked overnight shifts.

"When chronotype was not matched with work hours we saw an increase in type 2 diabetes risk," said Huang. "That was another very interesting finding suggesting that more personalized work scheduling could be beneficial."

The Nurses' Health Study is comprised mainly of white female nurses -- future investigations will be needed to determine if the patterns detected here are consistent across populations. The study's results point to associations but cannot determine causality -- it's possible that other factors may contribute to a person's chronotype, propensity for unhealthy habits and risk of diabetes.

Next, the researchers plan to investigate genetic determinants of chronotype and its association with cardiovascular disease, in addition to diabetes, in larger, more diverse populations.

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Snaps supersonic outflow of young star

Herbig-Haro (HH) objects are luminous regions surrounding newborn stars, formed when stellar winds or jets of gas spewing from these newborn stars form shock waves colliding with nearby gas and dust at high speeds. This image of HH 211 from NASA's James Webb Space Telescope reveals an outflow from a Class 0 protostar, an infantile analog of our Sun when it was no more than a few tens of thousands of years old and with a mass only 8% of the present-day Sun (it will eventually grow into a star like the Sun).

Infrared imaging is powerful in studying newborn stars and their outflows, because such stars are invariably still embedded within the gas from the molecular cloud in which they formed. The infrared emission of the star's outflows penetrates the obscuring gas and dust, making a Herbig-Haro object like HH 211 ideal for observation with Webb's sensitive infrared instruments. Molecules excited by the turbulent conditions, including molecular hydrogen, carbon monoxide, and silicon monoxide, emit infrared light that Webb can collect to map out the structure of the outflows.

The image showcases a series of bow shocks to the southeast (lower-left) and northwest (upper-right) as well as the narrow bipolar jet that powers them. Webb reveals this scene in unprecedented detail -- roughly 5 to 10 times higher spatial resolution than any previous images of HH 211. The inner jet is seen to "wiggle" with mirror symmetry on either side of the central protostar. This is in agreement with observations on smaller scales and suggests that the protostar may in fact be an unresolved binary star.

Earlier observations of HH 211 with ground-based telescopes revealed giant bow shocks moving away from us (northwest) and moving towards us (southeast) and cavity-like structures in shocked hydrogen and carbon monoxide respectively, as well as a knotty and wiggling bipolar jet in silicon monoxide. Researchers have used Webb's new observations to determine that the object's outflow is relatively slow in comparison to more evolved protostars with similar types of outflows.

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Freshwater connectivity can transport environmental DNA through the landscape

A new paper published in the journal Proceedings of the Royal Society B used environmental DNA (eDNA) metabarcoding to analyze fish and zooplankton communities. The study found that the movement of water between freshwater bodies, or freshwater connectivity, can transport eDNA. This highlights the potential of eDNA to provide a comprehensive view of freshwater biodiversity.

Aquatic ecosystems are connected by waterways, which allow fish, plants, and other organisms to move from one place to another. This connectivity is important for the resilience of aquatic populations, but it can also make it difficult to track the DNA of these organisms.

The study, led by Dr Joanne Littlefair, a lecturer in biological sciences at Queen Mary University of London, looked at three lake networks containing 21 lakes in Canada's Boreal Forest at IISD Experimental Lakes Area. The researchers found that within-lake eDNA generally reflected the habitat preferences of the species, but that some eDNA was also transported into downstream lakes. Lakes with a higher degree of connectivity had more eDNA detections that could not be explained by conventional monitoring techniques.

The findings have implications for the use of eDNA to monitor biodiversity in freshwater ecosystems. eDNA is a promising tool for biodiversity monitoring, but data must be interpreted in light of connectivity in the landscape.

"eDNA can be used to detect the presence of species that are not easily monitored using conventional methods, including invasive species, or for monitoring the presence of rare or endangered species," said Dr Littlefair." "Our study showed that eDNA surveys can be carefully designed to consider the connectivity of the freshwater system being studied. In systems with high levels of connectivity, it is important to collect samples from multiple locations, which will allow us to build a complete picture of the biodiversity present."

The study also highlights the need for more research on the factors, such as effects of water movement, influencing the spatial resolution of eDNA detection. For example, if the water in an ecosystem is moving quickly, then it may be necessary to collect more samples to increase the chances of detecting eDNA. This research will help to improve scientists' understanding of how eDNA can be used to monitor and conserve aquatic biodiversity.

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How just one set of animal tracks can provide a wealth of information

Rock faces in Namibia are decorated with hundreds of stone-age images not only of animals and human footprints, but also of animal tracks. These have been largely neglected to date as researchers lacked the knowledge required to interpret them. Archaeologists from Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU) and the University of Cologne have now worked together with animal tracking experts from the Nyae Nyae Conservancy in Tsumkwe, Namibia, to investigate the engraved animal tracks on six rock faces in more detail, and were able to determine detailed information on the species, age, sex, limbs, side of the body, trackway and relative direction of the tracks.

In the Doro !nawas mountains in the Namib desert in northwest Central Namibia, vegetation is sparse, trees and bushes generally only grow along small dry river beds. Thanks to various permanent waterholes, however, there is an unusually high occurrence of different animals: springboks, giraffes, elephants, lions and leopards all cross the area. The area remains untouched by humans at the current time. It is not inhabited or exploited in any other way. It was a different story in the past, however. Numerous instances of rock art representing animals as well as human footprints and animal tracks show that stone age hunters and gatherers lived here in the past.

Until now, archaeologists have only been able to interpret the species of the animals depicted in the rock art. Animal tracks tended to be classified together with the abstract symbols. "Researchers have until now completely neglected the fact that traces and tracks are also a valuable source of information," explains PD Dr. Andreas Pastoors from the Institute for Prehistory and Protohistory at FAU. Together with his FAU colleagues Prof. Dr. Thorsten Uthmeier and Dr. Tilman Lenssen-Erz from the African Research Institute at the University of Cologne, Pastoors has therefore taken a new approach, merging western archaeological science with indigenous knowledge in an innovative research project. The project began in 2013, when San tracking experts from Namibia read human footprints on the floor of caves in France decorated with rock art from the Ice Age. Now together with the Namibian tracking experts Tsamgao Ciqae, Ui Kxunta and Thui Thao from the Nyae Nyae Conservancy in Namibia, the three researchers set up camp for approximately one week in the Doro !nawas mountains, and investigated six rock faces depicting a particularly large number of human footprints and animal tracks.

The investigated rock faces are at the edge of an area resembling a crater with a diameter of approximately one kilometer in the Doro !nawas mountains. "At the upper edge there are large boulders with flat surfaces which people in the Stone Age decorated with rock art," explains Pastoors. The rock art shows various different motifs, ranging from human footprints to people and animals such as elephants, giraffes, rhinoceroses and ostriches. "These images are easily recognizable by western archaeologists," says Pastoors. However, they also depict animal tracks that have until now only been classified together with the abstract symbols. "Seen from the perspective of western art history, researchers are unable to recognize anything in these images, as they are lacking the relevant expertise. For this reason, the tracks have not yet been assessed as a legible source of information, which has in turn led to misleading hierarchies being created with regard to the value of the various images."

Stone age illustrations of animal tracks prove to be a valuable source of information

The study that has now been published counteracts this trend. Tsamgao Ciqae, Ui Kxunta und Thui Thao have discovered surprising details in the rock art. In more than 90 percent of the analyzed 513 images they were able to determine the species, age range, sex, specific limbs, side of the body and the direction of the animal tracks or human footprints. Interestingly, the animal tracks indicated a larger variety of species than those in the pictures of animals illustrated in profile in rock art in neighboring regions. The team of researchers was able to identify 20 further animal species in the animal tracks, ranging from bushpig, buffalo, monkey and caracal to various different types of antelopes (duiker, bushbuck, roan antelope, ibex), to bird species such as red-crested korhaan and marabou. One rather surprising aspect is that some of these species require damper conditions than those found in this part of Namibia, at least at the current time. But then why did the stone-age artists draw them? How did they know about them? "We cannot answer these questions with the state of research as it stands at present," admits Pastoors. However, it is plausible that the artists knew other regions with damper environmental conditions, as the Doro !nawas mountains were similarly dry as they are today."

In addition, the analyses show patterns that are obviously the result of cultural preferences. This includes, for example, the relative direction of the individual animal tracks that the tracking experts were able to decipher from the images. "We beamed a virtual clock onto the rock face and then noted the direction of the tracks according to the hours on the clock face." The result: Most tracks pointed upwards towards 12 o'clock, only a few pointed down towards 6 o'clock. The one exception were the zebra tracks. They were depicted traveling in all directions. "It's really exciting to see that the animal tracks can give us far more information that we originally thought," summarizes Pastoors.

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New evidence indicates patients recall death experiences after cardiac arrest

Up to an hour after their hearts had stopped, some patients revived by cardiopulmonary resuscitation (CPR) had clear memories afterward of experiencing death and had brain patterns while unconscious linked to thought and memory, report investigators in the journal Resuscitation, published by Elsevier.

In a study led by researchers at NYU Grossman School of Medicine, in cooperation with 25 mostly US and British hospitals, some survivors of cardiac arrest described lucid death experiences that occurred while they were seemingly unconscious. Despite immediate treatment, fewer than 10% of the 567 patients studied, who received CPR in the hospital, recovered sufficiently to be discharged. Four in 10 of patients who survived, however, recalled some degree of consciousness during CPR not captured by standard measures.

The study also found that in a subset of these patients, who received brain monitoring, nearly 40% had brain activity that returned to normal, or nearly normal, from a "flatline" state, at points even an hour into CPR. As captured by EEG, a technology that records brain activity with electrodes, the patients saw spikes in the gamma, delta, theta, alpha, and beta waves associated with higher mental function.

Survivors have long reported having heightened awareness and powerful, lucid experiences, say the study authors. These have included a perception of separation from the body, observing events without pain or distress, and a meaningful evaluation of their actions and relationships. This new work found these experiences of death to be different from hallucinations, delusions, illusions, dreams, or CPR-induced consciousness.

The study authors hypothesize that the "flatlined," dying brain removes natural inhibitory (braking) systems. These processes, known collectively as disinhibition, may open access to "new dimensions of reality," they say, including lucid recall of all stored memories from early childhood to death, evaluated from the perspective of morality. While no one knows the evolutionary purpose of this phenomenon, it "opens the door to a systematic exploration of what happens when a person dies."

Senior study author Sam Parnia, MD, PhD, associate professor in the Department of Medicine at NYU Langone Health and director of critical care and resuscitation research at NYU Langone, says, "Although doctors have long thought that the brain suffers permanent damage about 10 minutes after the heart stops supplying it with oxygen, our work found that the brain can show signs of electrical recovery long into ongoing CPR. This is the first large study to show that these recollections and brain wave changes may be signs of universal, shared elements of so-called near-death experiences."

Dr. Parnia adds, "These experiences provide a glimpse into a real, yet little understood dimension of human consciousness that becomes uncovered with death. The findings may also guide the design of new ways to restart the heart or prevent brain injuries and hold implications for transplantation."

Called the AWAreness during REsuscitation (AWARE)-II study -- it followed 567 men and women who suffered cardiac arrest during hospital stays between May 2017 and March 2020 in the United States and United Kingdom. Only hospitalized patients were enrolled to standardize the CPR and resuscitation methods used, as well as recording methods for brain activity. A subset of 85 patients received brain monitoring during CPR. Additional testimony from 126 community survivors of cardiac arrest with self-reported memories was also examined to provide greater understanding of the themes related to the recalled experience of death.

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Discovery of two potential Polar Ring galaxies suggests these stunning rare clusters might be more common than previously believed

A group of international astronomers, including researchers from Queen's University, has identified two potential polar ring galaxies, according to results published today in the Monthly Notices of the Royal Astronomical Society.

Queen's researchers Nathan Deg and Kristine Spekkens (Physics, Engineering Physics & Astronomy) led the analysis of data obtained using a telescope owned and operated by CSIRO, Australia's national science agency. Looking at sky maps of hydrogen gas in over 600 galaxies as part of CSIRO's ASKAP radio telescope's WALLABY survey, they identified two potential polar ring galaxies, a type of galaxy that exhibits a ring of stars and gas perpendicular to its main spiral disk.

Although this is not the first time that astronomers have observed polar ring galaxies, they are the first observed using the ASKAP telescope located at Inyarrimanha Ilgari Bundara, CSIRO's Murchison radio astronomy observatory on Wajarri Yamaji Country in Western Australia.

These new detections in gas alone suggest polar ring galaxies might be more common than previously believed.

Understanding how galaxies evolve

Further investigation of polar ring structures can help us better understand how galaxies evolve. For example, one of the main hypotheses to explain the origin of polar rings is a merger where a larger galaxy 'swallows' a smaller one. If polar ring galaxies are more common than previously thought, this could mean that these mergers are more frequent.

In the future, polar ring galaxies can also be used to deepen our understanding of the universe, with potential applications in dark matter research. It is possible to use polar rings to probe the shape of dark matter of the host galaxy, which could lead to new clues about the mysterious properties of the elusive substance.

Visualizing polar ring galaxies

Jayanne English, a member of the WALLABY research team and also an expert in astronomy image-making at the University of Manitoba, developed the first images of these gaseous polar ring galaxies using a combination of optical and radio data from the different telescopes. First, optical and infrared data from the Subaru telescope in Hawaii provided the image for the spiral disk of the galaxy. Then, the gaseous ring was added based on data obtained from the WALLABY survey, an international project using CSIRO's ASKAP radio telescope to detect atomic hydrogen emission from about half a million galaxies.

The creation of this and other astronomical images are all composite because they include information that our eyes can't capture. In this particular case, the cold hydrogen gas component, invisible to the human eye, is seen in radio "light" using CSIRO's ASKAP. The subtle colour gradient of this ring represents the orbital motions of the gas, with purple-ish tints at the bottom tracing gas that moves towards the viewer while the top portion moves away. The emission from the ring was separated from the radio emission emanating from the disk of the galaxy using virtual reality tools, in collaboration with Professor Tom Jarrett (University of Cape Town, South Africa).

Over 25 global collaborators from Canada, Australia, South Africa, Ecuador, Burkina Faso, Germany, China, and beyond worked together to analyze the data from the first public data release of the WALLABY survey, resulting in the newly published paper.

The next step for the team is to confirm the polar ring galaxies finding through additional observations using different telescopes, including the MeerKAT radio telescope in South Africa.

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100-year floods could occur yearly by end of 21st century

Most coastal communities will encounter 100-year floods annually by the end of the century, even under a moderate scenario where carbon dioxide emissions peak by 2040, a new study finds. And as early as 2050, regions worldwide could experience 100-year floods every nine to fifteen years on average.

A 100-year flood is an extreme water level that has a 1% chance of being exceeded in any given year and is based on historical data. Despite the name, 100-year floods can strike the same area multiple years in a row or not at all within a century. But a new study finds that those historical trends will no longer provide an accurate outlook for future floods.

"The threshold that we expect to be exceeded once every hundred years on average is going to be exceeded much more frequently in a warmer climate until they are no longer considered 100-year events," said Hamed Moftakhari, a civil engineer and professor at the University of Alabama who supervised the project. The study was published in Earth's Future, AGU's journal for interdisciplinary research on the past, present and future of our planet and its inhabitants.

On the coast, extreme floods can be caused by water pushed inland by storms, tides and waves, but this study focuses on a component that contributes to flooding over a much longer time scale -- sea level rise. As higher seas creep up the shore, coastal infrastructure will be closer to the water, making storms, tides and waves more likely to impact communities.

The researchers used data from more than 300 tide gauges around the world to conduct trend analyses and estimate future extreme sea levels under two carbon emission scenarios outlined by the International Panel on Climate Change: if carbon dioxide emissions continue to rise through the end of the century, and if carbon dioxide emissions reach their peak by 2040 and then decline. In both scenarios they found that sea level rise will lead to an increase in 100-year flood events in most of the locations they studied.

A proactive approach to land planning, urban development and coastal protective measures could help communities reduce flooding and avoid disaster, Moftakhari said, and that starts with realistic forecasts of future coastal conditions.

Building a safer future

Engineers who design structures such as sea dykes, seawalls and breakwaters to protect communities from these extreme floods rely on a concept known as stationarity to predict future water levels.

"In stationarity, we assume that the patterns we have observed in the past are going to remain unchanged in the future, but there are a lot of factors under climate change that are modulating these patterns," said Moftakhari. "We can't assume stationarity in coastal flooding anymore."

Previous studies relied on stationary estimates of extreme sea levels to predict 100-year floods, but this study used non-stationary methods and found that the shift in extreme sea levels will not be uniform for many tide-gauge locations.

As the climate changes, warmer ocean temperatures and meltwater from glaciers are causing sea levels to rise, increasing the frequency and severity of coastal flooding. As a result, engineers need accurate estimates of future flood risk that don't assume our changing future will reflect historic coastal patterns.

"What makes it so challenging is that the majority of tools, design guidelines, manuals of practice and more are all based on the assumption of stationarity," said Moftakhari. "They need to be updated to enable us to keep pace with the rate of change."

More than 600 million people live in low-lying coastal regions, according to another study. That number is expected to rise. Well-designed coastal defense structures play an important role in coastal communities' ability to withstand major flooding.

While mean sea level is rising, the outcome won't be the same everywhere. Higher latitudes may experience a drop in sea levels as heavy ice sheets melt and the land underneath rises. Alternatively, regions like the Gulf of Mexico are experiencing rates of sea level rise that are faster than the global average because the land is gradually sinking. According to Moftakhari, coastal communities will require unique solutions based on local information to match their needs.

"We know that mean sea level is rising, the question is: how are we going to deal with it?" said Moftakhari. "We've already seen that many portions of the coast are permanently inundated and losing land, and many coastal cities and islands are experiencing flooding much more frequently than in the past -- it's time to learn how to deal with non-stationarity."

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Shipboard cannon found off the Swedish coast may be the oldest in Europe

An international research team led by maritime archaeologist Staffan von Arbin of the University of Gothenburg has studied what might be Europe's oldest shipboard cannon. The cannon was found in the sea off Marstrand on the Swedish west coast and dates back to the 14th century. The findings from the interdisciplinary study contribute new knowledge about the early development of artillery on land and at sea, but also bears witness to a troubled period for seafarers as well as coastal populations.

The small, muzzle-loading cast copper-alloy cannon, found by a recreational diver at a depth of 20 metres in the sea off Marstrand, is believed to come from a shipwreck. The researchers conclude that it is a shipboard cannon, and not a cannon that was being transported as cargo, because it still had parts of a charge left in its powder chamber when it was found. This means the cannon was loaded and ready for use in combat at the time it ended up on the sea floor.

"Thanks to the preserved remains of the charge, it has been possible to use radiocarbon dating to establish the age of the find," says Staffan von Arbin, maritime archaeologist at the University of Gothenburg.

"The study's findings show that the Marstrand cannon is probably from the 14th century, making it one of the oldest artillery pieces ever found in Europe."

The researchers documented the find with 3D scanning, and also conducted a chemical analysis of the metal used to cast the cannon. The analysis showed that it was a copper alloy containing about 14 weight per cent lead and only small amounts of tin.

This alloy is far from optimal for casting cannon according to the researchers, and it is likely that the cannon would have cracked and been rendered unusable if used intensively for longer periods.

"Clearly, the person who cast the cannon did not have the necessary knowledge and understanding of the properties of various copper alloys," says Staffan von Arbin.

"This shows that the noble art of cannon casting had not yet been fully mastered at that time, and that production was largely based on trial and error."

The analysis also indicates that the copper ore used in the cannon's production was mined in present-day Slovakia, while the lead probably came from England or the border region between Poland and the Czech Republic.

Important hub for commercial shipping

In this interdisciplinary study published in the English maritime history journal The Mariner's Mirror, the researchers present the results of the analyses they carried out, but also discuss the find in light of documentary, iconographic and archaeological sources. In the 14th century, the town of Marstrand, famous for its excellent port, was an important hub for commercial shipping between Western Europe and the Baltic Sea area. But the sea was also an arena for war and conflict, and coastal civilian populations were often hit hard. In addition, there was always a risk of attacks by pirates.

The new types of firearms developed at this time provided great tactical advantages in battles at sea. But it wasn't just warships that were armed -- during the late Middle Ages merchant ships also started being equipped with cannon more and more often to defend themselves against pirates and other hostile vessels. The study of the Marstrand cannon provides new knowledge and perspectives on the development of this military technology.

Funnel-shaped cannons of the Marstrand cannon type are usually attributed to the 15th-16th centuries, but this find is testimony to the fact that this model already existed in the 14th century. The preserved remains of the charge in the cannon's powder chamber also show that the use of cartouches, a kind of textile packaging for the powder charge, came into use much earlier than previously known.

"Now, of course, we also want to try to locate and document the ship that the cannon belonged to. Although it is probably severely degraded and broken up, it should be possible to find scattered remains of the wreck if we conduct a thorough inventory of the site and its surroundings," says Staffan von Arbin.

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Mysterious family of microbial proteins hijack crops' cellular plumbing

Many of the bacteria that ravage crops and threaten our food supply use a common strategy to cause disease: they inject a cocktail of harmful proteins directly into the plant's cells.

For 25 years, biologist Sheng-Yang He and his senior research associate Kinya Nomura have been puzzling over this set of molecules that plant pathogens use to cause diseases in hundreds of crops worldwide ranging from rice to apple trees.

Now, thanks to a team effort between three collaborating research groups, they may finally have an answer to how these molecules make plants sick -- and a way to disarm them.

The findings appear Sept. 13 in the journal Nature.

Researchers in the He lab study key ingredients in this deadly cocktail, a family of injected proteins called AvrE/DspE, that cause diseases ranging from brown spot in beans and bacterial speck in tomatoes to fire blight in fruit trees.

Ever since their discovery in the early 1990s, this family of proteins has been of great interest to those who study plant disease. They are key weapons in the bacterial arsenal; knocking them out in a lab renders otherwise-dangerous bacteria harmless. But, despite decades of effort, many questions about how they work remain unanswered.

Researchers had identified a number of proteins in the AvrE/DspE family that suppressed the plant's immune system, or that caused dark water-soaked spots on a plant's leaves -- the first telltale signs of infection. They even knew the underlying sequence of amino acids that linked to form the proteins, like beads on a string. But they didn't know how this string of amino acids folded into a 3D shape, so they couldn't easily explain how they worked.

Part of the problem is that the proteins in this family are huge. Whereas an average bacterial protein might be 300 amino acids long; AvrE/DspE-family proteins are 2000.

Researchers have looked for other proteins with similar sequences for clues, but none with any known functions showed up.

"They're weird proteins," He said.

So they turned to a computer program released in 2021 called AlphaFold2, which uses artificial intelligence to predict what 3D shape a given string of amino acids will take.

The researchers knew that some members of this family help the bacteria evade the plant's immune system. But their first glimpse of the proteins' 3D structure suggested an additional role.

"When we first saw the model, it was nothing like what we had thought," said study co-author Pei Zhou, a professor of biochemistry at Duke whose lab contributed to the findings.

The researchers looked at AI predictions for bacterial proteins that infect crops including pears, apples, tomatoes and corn, and they all pointed to a similar 3D structure. They appeared to fold into a tiny mushroom with a cylindrical stem, like a straw.

The predicted shape matched up well with images of a bacterial protein that causes fire blight disease in fruit trees that was captured using a cryo-electron microscope. From the top down, this protein looked very much like a hollow tube.

Which got the researchers thinking: Perhaps bacteria use these proteins to punch a hole in the plant cell membrane, to "force the host for a drink" during infection, He said.

Once bacteria enter the leaves, one of the first areas they come across is a space between cells called the apoplast. Normally, plants keep this area dry to enable gas exchange for photosynthesis. But when bacteria invade, the inside of the leaf becomes waterlogged, creating a moist cozy haven for them to feed and multiply.

Further examination of the predicted 3D model for the fire blight protein revealed that, while the outside of the straw-like structure is water-resistant, its hollow inner core has a special affinity for water.

To test the water channel hypothesis, the team joined forces with Duke biology professor Ke Dong and co-first-author Felipe Andreazza, a postdoctoral associate in her lab. They added the gene readouts for the bacterial proteins AvrE and DspE to frog eggs, using the eggs as cellular factories for making the proteins. The eggs, placed in a dilute saline solution, quickly swelled and burst with too much water.

The researchers also tried to see if they could disarm these bacterial proteins by blocking their channels. Nomura focused on a class of tiny spherical nanoparticles called PAMAM dendrimers. Used for more than two decades in drug delivery, these dendrimers can be made with precise diameters in a lab.

"We were tinkering with the hypothesis that if we found the right diameter chemical, maybe we could block the pore," He said.

After testing different sized particles, they identified one they thought might be just the right size for jamming the water channel protein produced by the fire blight pathogen, Erwinia amylovora.

They took frog eggs engineered to synthesize this protein and doused them with the PAMAM nanoparticles, and water stopped flowing into the eggs. They didn't swell.

They also treated Arabidopsis plants infected with the pathogen Pseudomonas syringae, which causes bacterial speck. The channel-blocking nanoparticles prevented the bacteria from taking hold, reducing pathogen concentrations in the plants' leaves by 100-fold.

The compounds were effective against other bacterial infections too. The researchers did the same thing with pear fruits exposed to the bacteria that cause fire blight disease, and the fruits never developed symptoms -- the bacteria didn't make them sick.

"It was a long shot, but it worked," He said. "We're excited about this."

The findings could offer a new line of attack against many plant diseases, the researchers said.

Plants produce 80% of the food we eat. And yet more than 10% of global food production -- crops such as wheat, rice, maize, potato and soybean -- are lost to plant pathogens and pests each year, costing the global economy a whopping $220 billion.

The team has filed a provisional patent on the approach.

The next step, said Zhou and co-first-author Jie Cheng, a Ph.D. student in Zhou's lab, is to figure out how this protection works, by getting a more detailed look at how the channel-blocking nanoparticles and the channel proteins interact.

"If we can image those structures we can have a better understanding and come up with better designs for crop protection," Zhou said.

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Dark matter halos measured around ancient quasars

At the center of every galaxy is a supermassive black hole. Beyond a certain size, these become active, emitting huge amounts of radiation, and are then called quasars. It is thought these are activated by the presence of massive dark matter halos (DMH) surrounding the galaxy, directing matter towards the center, feeding the black hole. A team including researchers from the University of Tokyo have, for the first time, surveyed hundreds of ancient quasars and found this behavior is very consistent throughout history. This is surprising, as many large-scale processes show variation throughout the life of the universe, so the mechanism of quasar activation could have implications for the evolution of the entire universe.

Measuring the mass of DMHs is not easy; it's famously a very elusive substance, if substance is even the right word to use, given the actual nature of dark matter is unknown. We only know it exists at all due to its gravitational impact on large structures such as galaxies. Thus, dark matter can only be measured by making observations about its gravitational effects on things. This includes the way it might pull on something or affect its movement, or through the lensing (bending of light) of objects behind a suspected area of dark matter.

The challenge becomes greater at large distances, given how weak the light from more distant, and therefore ancient, phenomena can be. But this did not stop Professor Nobunari Kashikawa from the Department of Astronomy, and his team, from trying to answer a long-standing question in astronomy: How are black holes born, and how do they grow? The researchers are especially keen to explore this in relation to supermassive black holes, the largest kind, which exist in the heart of every galaxy. These would be very difficult to study were it not for the fact that some grow so massive they begin to output incredibly powerful jets of matter or spheres of radiation that in either case become what we call quasars. These are so powerful that even at large distances, we can now observe them using modern techniques.

"We measured for the first time the typical mass for dark matter halos surrounding an active black hole in the universe about 13 billion years ago," said Kashikawa. "We find the DMH mass of quasars is pretty constant at about 10 trillion times the mass of our sun. Such measurements have been made for more recent DMH around quasars, and those measurements are strikingly similar to what we see for more ancient quasars. This is interesting because it suggests there is a characteristic DMH mass which seems to activate a quasar, regardless of whether it happened billions of years ago or right now."

Quasars at great distances appear faint, as the light which left them long ago has spread out, was absorbed by intervening matter, and has been stretched into nearly invisible infrared wavelengths due to the universe expanding over time. So Kashikawa and his team, whose project began in 2016, used multiple surveys of the sky which incorporated a range of different instruments, the main one being Japan's Subaru Telescope, located in U.S. state of Hawaii.

Read more at Science Daily

Movement sensors can detect disease in wild boar

Behavioral sensors attached to wild boars have been used to detect when animals are sick with African Swine Fever, a fatal viral disease that affects both boar and domestic pigs. Accelerometer sensors, which measure tiny changes in movement, showed that wild boars reduced their daily activity by up to 20 percent when infected with the virus. The findings, published by scientists from the Max Planck Institute of Animal Behavior, show that lightweight sensors can detect sickness behavior in wild boar -- raising the possibility of a minimally invasive tool to assist in the control and prevention of African Swine Fever.

Although the virus cannot be transmitted to humans, African Swine Fever is a major threat to the global pig industry and has significant economic and social impact. The highly contagious virus spreads easily between wild boar and domestic pigs, and so knowing when a disease outbreak occurs in the wild and on farms is important for curbing the spread of African Swine Fever. But detecting disease in wild animals is not straight forward. Currently, testing for African Swine Fever in wild boar is done by sampling animals that are either hunted or found dead, which creates a long lag between when the disease emerges in a population to when it is actually detected.

Seeking to reduce this lag, scientists from Germany, Spain and Austria teamed up to investigate if technology that 'reads' an animal's behavior could be harnessed for early detection of disease in wild boar. Their findings point to the potential of accelerometer sensors as an accessible tool that can support the existing disease management approaches for African Swine Fever surveillance and control. "This is a game-changer for wildlife disease monitoring," says Kevin Morelle, first author of the study and a scientist with the Max Planck Institute of Animal Behavior. "We show that a lightweight behavioral sensor deployed on a wild animal can be a sentinel for potential health threats."

Accelometers measure animals' movements

The scientists attached accelerometer tags, weighting 30 grams, on twelve wild boars that were studied in controlled conditions. The boars were infected with African Swine Fever as part of a separate study aimed at developing a vaccine against the disease. The accelerometers, which are the equivalent of 'Fitbits' or pedometers, took ultra-high resolution measurements of the animals' movements. The measurements, called 'Overall Dynamic Body Acceleration', showed how much the boars were active. The scientists found that when boars became sick with African Swine Fever, they were ten to twenty percent less active daily than when they were healthy. To validate the findings, the study authors attached accelerometers to a group of healthy boars living in natural conditions. They then compared the activity patterns of infected and healthy wild boar.

Read more at Science Daily

Exposure to air pollution while in the womb is linked to adverse changes in cell processes in new-born babies

Exposure to air pollution while in the womb is linked to alterations in proteins that can be detected after a baby is born, and which affect cell processes such as autophagy, the "self-eating" of damaged cells that occurs in response to stress.

Dr Olga Gorlanova, a research physician at the University Children's Hospital, University of Basel, Switzerland, told the European Respiratory Society International Congress in Milan, Italy, that her study also showed that healthy, new-born babies had individual and different responses to their mothers' exposure to air pollution during pregnancy. This might mean that some babies were more vulnerable to it than others. This was the case even if they were born into households in areas with relatively low levels of pollution.

Earlier work by Dr Gorlanova and her colleagues had shown that exposure to air pollution during pregnancy could affect lung function and the immune system in new-borns. In the current study, they looked at proteins involved in autophagy, ageing and cell remodelling to see how prenatal exposure to air pollution could affect them.

The researchers measured 11 proteins found in the cord blood of 449 healthy new-born babies from the Bern Basel Infant Lung Development (BILD) cohort study. The BILD study, started in 1999 in Bern, aims to recruit 1000 babies by 2025. It is investigating the effects of genetics and the environment (particularly air pollution) on lung development in babies and children.

Dr Gorlanova and colleagues measured the mothers' exposure to nitrogen dioxide (NO2) and tiny particles called PM10,which areparticulate matter measuring 10 microns or less in diameter. Vehicle emissions, tyre and brake wear, and smoke are some of the sources of these pollutants. They found that NO2 and PM10 were both linked to changes in proteins involved in autophagy. Exposure to NO2 was linked to a decrease in the activity of the proteins SIRT1 and IL-8, and an increase in levels of the Beclin-1 protein.

"Our results indicate that NO2, a pollutant formed mainly from traffic emissions, is associated with increased levels of Beclin-1 protein, which is central to initiating autophagy. Exposure to higher NO2 was also linked to decreased levels of SIRT1, which is a protein that plays a protective role in stress resistance, inflammation and aging. IL-8 is a protein active in certain inflammatory cells," said Dr Gorlanova.

"We grouped the babies into four distinct clusters according to the levels of air pollution they were exposed to while in the womb. The four clusters all had similar concentrations of the proteins being studied but had differences their exposure to NO2 and PM10 air pollution. One cluster had low concentrations of nine proteins, while another cluster, consisting of seven percent of all the babies, had higher levels of proteins that are involved in inflammatory and remodelling processes: IL-8 and IL-1B. Both these groups of new-borns had been exposed to lower, although differing, levels of prenatal air pollution than the other two groups. Our findings suggest that healthy new-borns have an individual response pattern to air pollution. We think that this may be an indication that some babies are more vulnerable to it than others.

"Additionally, our work adds to the growing body of evidence that autophagy-related mechanisms may be involved in how human cells react to air pollution. The findings are consistent with evidence from tissue and animal research. Further exploration of these mechanisms may help to better understand the deleterious effects of pollution on infants."

The researchers plan to examine whether babies with distinct protein response patterns to air pollution will suffer from more breathing problems during infancy and childhood compared to those that do not show the same protein responses.

Professor Marielle Pijnenburg, associate professor of pediatric pulmonology and head of the Department of Pediatric Respiratory Medicine and Allergology at Erasmus Medical Center, Rotterdam, The Netherlands, is head of the ERS group on paediatrics and was not involved with the research. She commented: "This study adds to the growing body of evidence that air pollution can affect the health of children before and after they are born. It contributes to other research showing that autophagy-related mechanisms may be involved in how human cells react to air pollution. We need to know more about how these mechanisms can affect the health of lungs, and we need to understand why some new-borns seem to be more susceptible to air pollution than others.

Read more at Science Daily

Plant-based food alternatives could support a shift to global sustainability

Replacing 50% of meat and milk products with plant-based alternatives by 2050 can reduce agriculture and land use related greenhouse gas (GHG) emissions by 31% and halt the degradation of forest and natural land, according to new research.

According to the study just published in Nature Communications, additional climate and biodiversity benefits could accrue from reforesting land spared from livestock production when meat and milk products are substituted by plant-based alternatives, more than doubling the climate benefits and halving future declines of ecosystem integrity by 2050. The restored area could contribute up to 25% of the estimated global land restoration needs under Target 2 of the Kunming Montreal Global Biodiversity Framework by 2030.

The study is the first to look at the global food security and environmental impacts of plant-based meat and milk consumption at large scales that considers the complexity of food systems. The research was conducted independently by IIASA in partnership with the Alliance of Bioversity and CIAT, as well as USAID, and solicited input from Impossible Foods -- a company that develops plant-based substitutes for meat products -- as a potential user of the data to ensure relevance. The company also provided generic recipes for the plant-based meat substitute products used in the analysis. The data are, however, not specific to Impossible Foods and the science team had complete control over decision making.

"Understanding the impacts of dietary shifts expands our options for reducing GHG emissions. Shifting diets could also yield huge improvements for biodiversity," notes study lead author Marta Kozicka, a researcher in the IIASA Biodiversity and Natural Resources Program.

"Plant-based meats are not just a novel food product, but a critical opportunity for achieving food security and climate goals while also achieving health and biodiversity objectives worldwide. Yet, such transitions are challenging and require a range of technological innovations and policy interventions," adds study coauthor Eva Wollenberg from Alliance of Bioversity International and CIAT and the Gund Institute, University of Vermont.

The authors developed scenarios of dietary changes based on plant-based recipes for beef, pork, chicken, and milk. The recipes were designed to be nutritionally equivalent to the original animal-derived protein products and realistic for the existing food manufacturing capabilities and globally available production ingredients (Fig 1).

The authors found that a 50% substitution scenario would substantially reduce the mounting impacts of food systems on the natural environment by 2050 compared to the reference scenario (Fig 2). The impacts as compared to 2020 include:

• Global agricultural area declines by 12% instead of expanding.
• The decline in areas of forest and other natural land is almost completely halted.
• Nitrogen inputs to cropland are nearly half of the projections.
• Water use declines by 10% instead of increasing.
• Without accounting for any carbon sequestration on spared land, GHG emissions could decline by 2.1 Gt CO2eq year-1 (31%) in 2050 (1.6 Gt CO2eq year-1 on average in 2020-2050).
• Undernourishment globally declines to 3.6%, as compared to 3.8% in the reference scenario (reducing the number of undernourished people by 31 million).

The full environmental benefit of diet shifts can be achieved if the agricultural land spared from livestock and feed production is restored through biodiversity-minded afforestation. In the 50% scenario, the benefits from reduced land-use emissions could double as compared to a scenario without afforestation -- a total reduction of 6.3 Gt CO2eq year-1. At 90% substitution, the reduction of all agriculture and land-use emissions would increase to 11.1 Gt CO2eq year-1 in 2050.

The restoration of forest ecosystems would also improve biodiversity. The 50% scenario would reduce predicted declines in ecosystem integrity by more than half, while the 90% scenario could reverse biodiversity loss between 2030 and 2040.

"While the analyzed dietary shifts serve as a powerful enabler for reaching climate and biodiversity goals, they must be accompanied by targeted production side policies to deliver their full potential. Otherwise, these benefits will be partly lost due to production extensification and resulting GHG and land-use efficiency losses," explains IIASA Biodiversity and Natural Resources Program Director Petr Havlík, who coordinated the study.

The study points out that impacts across regions could differ due to differences in population size and diets, unequal agricultural productivity, and participation in international trade of agricultural commodities. The main impacts on agricultural input use are in China and on environmental outcomes in Sub-Saharan Africa and South America. These regional differences could also be used to design better interventions.

"A global introduction of all novel alternatives has additional benefits compared to the scenarios with limited product or geographical scope, but regional substitution of specific products may be highly effective, especially if combined with regional strategies and purposeful selection of recipes," Kozicka explains.

Read more at Science Daily

Fewer but more intense tropical storms predicted over the Ganges and Mekong

Climate experts project a decline in the frequency of future tropical storms but an increase in their strength across the Ganges and Mekong basins allowing for better future planning.

The Newcastle University-led team focused on the Ganges and Mekong basins and evaluated the simulation of tropical storms. Their analyses show an increase in tropical storms frequency up until the early 2010s but that climate models project a frequency decline of over 50% on average across both basins by 2050.

In contrast, the results from high resolution climate models show an increase in the future intensity of tropical storms for both basins, with the largest increases for the most intense tropical storms.

These findings can be used to assess the future resilience of existing infrastructure systems to tropical storms across these densely populated basins.

The team, involving scientists from the Met Office and the University of Reading, published their findings in the journal Geophysical Research Letters. The scientists used European Union Horizon 2020 project PRIMAVERA models, which are available at up to 25 km resolution. They also employed two storm tracking algorithms, TRACK and TempExt.

Study lead author, Dr Haider Ali, of Newcastle University's School of Engineering, said: "Tropical storms are one of the world's most damaging natural hazards which result in colossal socioeconomic losses to life, infrastructure and property, especially in low-lying delta rivers basins like the Ganges and Mekong.

"Knowledge of changes to tropical storms activity under climate change can therefore be helpful in developing better disaster risk mitigation and for climate adaptation. Previous modelling studies have used coarse-resolution global climate models unable to capture key tropical storm characteristics.

"In this study, we used finer resolution models and two different tracking algorithms to resolve a part of this uncertainty."

Study author, Hayley Fowler, Professor of Climate Change Impacts, Newcastle University School of Engineering, added: "Our results are consistent with those found for tropical storms and Tropical Cyclones in the Atlantic Basin, where they also project an overall decline in frequency but an increase in the frequency of the most intense TCs. These systems cause massive impacts on society from high winds, rainfall and storm surges causing flooding. Quantifying these changes will allow us to better plan for future events."

Implications for Climate Adaptation Policies

The Ganges and Mekong basins are two significant river systems in Asia that play vital roles in the lives of millions of people living in the region. The basins are essential for agriculture, water supply, and transportation.

However, both the Ganges and Mekong basins are highly vulnerable to the impacts of climate change, including changes in precipitation patterns, extreme weather events, and sea-level rise.

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You say tomato, these scientists say evolutionary mystery

Biologists at the University of Massachusetts Amherst have found evidence for evolutionary "syndromes" -- sets of traits that occur together -- that help to explain how tomatoes first evolved their distinctive blend of color, sweetness, acidity and aroma. The research, represented by a pair of papers recently published in Plants People Planet and The American Journal of Botany, not only shines a light on how fruits evolve in the wild, but will also be valuable to crop-improvement efforts aimed at breeding more nutritious and appealing varieties of fruits.

"Have you ever held a fresh tomato in your hand and wondered why it looks good, smells good and tastes delicious?" asks Jacob Barnett, graduate student in organismic and evolutionary biology at UMass Amherst and the papers' lead author. It turns out that the juicy, red tomatoes with their unique flavor have a long and circuitous evolutionary history.

Barnett and his co-authors, including Ana Caicedo, professor of biology at UMass Amherst, turned to the relatives of our modern tomatoes, a group of several wild species growing in the western coast of South America, from Chile to Ecuador, to explore this question. And those wild species are nothing like what you'd find in your sandwich or salad today.

"For one thing, they're tiny," says Barnett, "about the size of a blueberry. And most of them are green when ripe. Many smell like apples, melons or even cucumbers, and a number of them taste terrible."

So how did we get from a tiny, green, terrible-tasting, melon-smelling fruit to the sublime blend of color, sweetness, acidity and umami that makes tomatoes so beloved in pasta sauces, salads and pizzas?

It turns out that fruits in the wild tend to have sets of traits that occur together, which biologists call syndromes. For example, many fruits are small, brightly colored and high in sugar. But evidence of evolutionary syndromes in wild tomatoes has been hard to gather, because no previous researchers had grown all the species of wild tomatoes together at the same time.

"These two studies are the first to look at fruit traits across all species in the entire tomato group," says Caicedo. "We have been able to tell a comprehensive story of how wild tomatoes compare to each other and to our modern, cultivated varieties."

Part of that story involves the collecting efforts of Charles Rick, from the University of California Davis, who traveled through South America in the 1950s and 1960s collecting seeds from wild species and bringing them back to what would become the C.M. Rick Tomato Genetics Resource Center. Barnett and Caicedo acquired seeds from 13 species of wild tomato, as well seeds from multiple variants within each species, and then grew them at the UMass Crop and Animal Research and Education Farm in South Deerfield, Massachusetts.

When mature, the plants were "wild and scraggly," says Caicedo, and at one point Barnett had to hack his way through them with a machete on his way to gathering their fruits and leaves. Back in the lab, the team scanned the fruits for color and shape, measured sugar and acid content and analyzed the DNA in the leaf samples. With the help of co-author Denise Tieman, research assistant professor at the University of Florida, Barnett measured and classified each sample's volatile organic compounds -- the chemicals responsible for tomatoes' smell.

Not only did the team discover that smell, flavor and color are syndromatic, they also discovered that there is what Barnett calls an "honest signal" -- a match between the outside appearance of the tomato and the inside nutritional content. This match supports a controversial hypothesis that animal preferences shaped the evolution of fruit syndromes, because animals will choose some fruits over others if they learn to associate the fruit's looks with its unique nutrient reward.

Read more at Science Daily

Water world? Methane, carbon dioxide in atmosphere of massive exoplanet

A new investigation with NASA's James Webb Space Telescope into K2-18 b, an exoplanet 8.6 times as massive as Earth, has revealed the presence of carbon-bearing molecules including methane and carbon dioxide. Webb's discovery adds to recent studies suggesting that K2-18 b could be a Hycean exoplanet, one which has the potential to possess a hydrogen-rich atmosphere and a water ocean-covered surface.

The first insight into the atmospheric properties of this habitable-zone exoplanet came from observations with NASA's Hubble Space Telescope, which prompted further studies that have since changed our understanding of the system.

K2-18 b orbits the cool dwarf star K2-18 in the habitable zone and lies 120 light-years from Earth in the constellation Leo. Exoplanets such as K2-18 b, which have sizes between those of Earth and Neptune, are unlike anything in our solar system. This lack of equivalent nearby planets means that these 'sub-Neptunes' are poorly understood, and the nature of their atmospheres is a matter of active debate among astronomers.

The suggestion that the sub-Neptune K2-18 b could be a Hycean exoplanet is intriguing, as some astronomers believe that these worlds are promising environments to search for evidence for life on exoplanets.

"Our findings underscore the importance of considering diverse habitable environments in the search for life elsewhere," explained Nikku Madhusudhan, an astronomer at the University of Cambridge and lead author of the paper announcing these results. "Traditionally, the search for life on exoplanets has focused primarily on smaller rocky planets, but the larger Hycean worlds are significantly more conducive to atmospheric observations."

The abundance of methane and carbon dioxide, and shortage of ammonia, support the hypothesis that there may be a water ocean underneath a hydrogen-rich atmosphere in K2-18 b. These initial Webb observations also provided a possible detection of a molecule called dimethyl sulfide (DMS). On Earth, this is only produced by life. The bulk of the DMS in Earth's atmosphere is emitted from phytoplankton in marine environments.

The inference of DMS is less robust and requires further validation. "Upcoming Webb observations should be able to confirm if DMS is indeed present in the atmosphere of K2-18 b at significant levels," explained Madhusudhan.

While K2-18 b lies in the habitable zone, and is now known to harbor carbon-bearing molecules, this does not necessarily mean that the planet can support life. The planet's large size -- with a radius 2.6 times the radius of Earth -- means that the planet's interior likely contains a large mantle of high-pressure ice, like Neptune, but with a thinner hydrogen-rich atmosphere and an ocean surface. Hycean worlds are predicted to have oceans of water. However, it is also possible that the ocean is too hot to be habitable or be liquid.

"Although this kind of planet does not exist in our solar system, sub-Neptunes are the most common type of planet known so far in the galaxy," explained team member Subhajit Sarkar of Cardiff University. "We have obtained the most detailed spectrum of a habitable-zone sub-Neptune to date, and this allowed us to work out the molecules that exist in its atmosphere."

Characterizing the atmospheres of exoplanets like K2-18 b -- meaning identifying their gases and physical conditions -- is a very active area in astronomy. However, these planets are outshone -- literally -- by the glare of their much larger parent stars, which makes exploring exoplanet atmospheres particularly challenging.

The team sidestepped this challenge by analyzing light from K2-18 b's parent star as it passed through the exoplanet's atmosphere. K2-18 b is a transiting exoplanet, meaning that we can detect a drop in brightness as it passes across the face of its host star. This is how the exoplanet was first discovered in 2015 with NASA's K2 mission. This means that during transits a tiny fraction of starlight will pass through the exoplanet's atmosphere before reaching telescopes like Webb. The starlight's passage through the exoplanet atmosphere leaves traces that astronomers can piece together to determine the gases of the exoplanet's atmosphere.

"This result was only possible because of the extended wavelength range and unprecedented sensitivity of Webb, which enabled robust detection of spectral features with just two transits," said Madhusudhan. "For comparison, one transit observation with Webb provided comparable precision to eight observations with Hubble conducted over a few years and in a relatively narrow wavelength range."

"These results are the product of just two observations of K2-18 b, with many more on the way," explained team member Savvas Constantinou of the University of Cambridge. "This means our work here is but an early demonstration of what Webb can observe in habitable-zone exoplanets."

The team's results were accepted for publication in The Astrophysical Journal Letters.

The team now intends to conduct follow-up research with the telescope's MIRI (Mid-Infrared Instrument) spectrograph that they hope will further validate their findings and provide new insights into the environmental conditions on K2-18 b.

Read more at Science Daily

Healthy lifestyle can help prevent depression -- and new research may explain why

A healthy lifestyle that involves moderate alcohol consumption, a healthy diet, regular physical activity, healthy sleep and frequent social connection, while avoiding smoking and too much sedentary behaviour, reduces the risk of depression, new research has found.

In research published today in Nature Mental Health, an international team of researchers, including from the University of Cambridge and Fudan University, looked at a combination of factors including lifestyle factors, genetics, brain structure and our immune and metabolic systems to identify the underlying mechanisms that might explain this link.

According to the World Health Organization, around one in 20 adults experiences depression, and the condition poses a significant burden on public health worldwide. The factors that influence the onset of depression are complicated and include a mixture of biological and lifestyle factors.

To better understand the relationship between these factors and depression, the researchers turned to the UK Biobank, a biomedical database and research resource containing anonymised genetic, lifestyle and health information about its participants.

By examining data from almost 290,000 people -- of whom 13,000 had depression -- followed over a nine-year period, the team was able to identify seven healthy lifestyle factors linked with a lower risk of depression. These were:
 

• moderate alcohol consumption
• healthy diet
• regular physical activity
• healthy sleep
• never smoking
• low-to-moderate sedentary behaviour
• frequent social connection

Of all of these factors, having a good night's sleep -- between seven and nine hours a night -- made the biggest difference, reducing the risk of depression, including single depressive episodes and treatment-resistant depression, by 22%.

Frequent social connection, which in general reduced the risk of depression by 18%, was the most protective against recurrent depressive disorder.

Moderate alcohol consumption decreased the risk of depression by 11%, healthy diet by 6%, regular physical activity by 14%, never smoking by 20%, and low-to-moderate sedentary behaviour by 13%.

Based on the number of healthy lifestyle factors an individual adhered to, they were assigned to one of three groups: unfavourable, intermediate, and favourable lifestyle. Individuals in the intermediate group were around 41% less likely to develop depression compared to those in the unfavourable lifestyle, while those in the favourable lifestyle group were 57% less likely.

The team then examined the DNA of the participants, assigning each a genetic risk score. This score was based on the number of genetic variants an individual carried that have a known link to risk of depression. Those with the lowest genetic risk score were 25% less likely to develop depression when compared to those with the highest score -- a much smaller impact than lifestyle.

In people at high, medium, and low genetic risk for depression, the team further found that a healthy lifestyle can cut the risk of depression. This research underlines the importance of living a healthy lifestyle for preventing depression, regardless of a person's genetic risk.

Professor Barbara Sahakian, from the Department of Psychiatry at the University of Cambridge, said: "Although our DNA -- the genetic hand we've been dealt -- can increase our risk of depression, we've shown that a healthy lifestyle is potentially more important.

"Some of these lifestyle factors are things we have a degree control over, so trying to find ways to improve them -- making sure we have a good night's sleep and getting out to see friends, for example -- could make a real difference to people's lives."

To understand why a healthy lifestyle might reduce the risk of depression, the team studied a number of other factors.

First off, they examined MRI brain scans from just under 33,000 participants and found a number of regions of the brain where a larger volume -- more neurons and connections -- was linked to a healthy lifestyle. These included the pallidum, thalamus, amygdala and hippocampus.

Next, the team looked for markers in the blood that indicated problems with the immune system or metabolism (how we process food and produce energy). Among those markers found to be linked to lifestyle were the C-reactive protein, a molecule produced in the body in response to stress, and triglycerides, one of the primary forms of fat that the body uses to store energy for later.

These links are supported by a number of previous studies. For example, exposure to stress in life can affect how well we are able to regulate blood sugar, which may lead to a deterioration of immune function and accelerate age-related damage to cells and molecules in the body. Poor physical activity and lack of sleep can damage the body's ability to respond to stress. Loneliness and lack of social support have been found to increase the risk of infection and increase markers of immune deficiency.

The team found that the pathway from lifestyle to immune and metabolic functions was the most significant. In other words, a poorer lifestyle impacts on our immune system and metabolism, which in turn increases our risk of depression.

Dr Christelle Langley, also from the Department of Psychiatry at the University of Cambridge, said: "We're used to thinking of a healthy lifestyle as being important to our physical health, but it's just as important for our mental health. It's good for our brain health and cognition, but also indirectly by promoting a healthier immune system and better metabolism."

Professor Jianfeng Feng, from Fudan University and Warwick University, added: "We know that depression can start as early as in adolescence or young adulthood, so educating young people on the importance of a healthy lifestyle and its impact on mental health should begin in schools."

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How to prevent biofilms in space

After exposure in space aboard the International Space Station, a new kind of surface treatment significantly reduced the growth of biofilms, scientists report. Biofilms are mats of microbial or fungal growth that can clog hoses or filters in water processing systems, or potentially cause illness in people.

In the experiment, researchers investigated a variety of surfaces treated in different ways and exposed to a bacteria called Pseudomonas aeruginosa, which is an opportunistic pathogen than can cause infections in humans, especially in hospitals. The surfaces were incubated for three days aboard the space station, starting in 2019. The results show that textured surfaces impregnated with a lubricant were highly successful at preventing biofilm growth during their long exposure in space. The findings are described in a paper in the journal Nature Microgravity, by Samantha McBride PhD '20 and Kripa Varanasi of MIT, Pamela Flores and Luis Zea at the University of Colorado, and Jonathan Galakza at NASA Ames Research Center.

Clogs in water recovery system hoses aboard the ISS have been so severe at times, the hoses had to be sent back to Earth for cleaning and refurbishing. And while it isn't known whether biofilms have directly contributed to astronaut illnesses, on Earth, biofilms are associated with 65 percent of microbial infections, and 80 percent of chronic infections, the researchers say.

One approach to preventing biofilms is to use surfaces coated with certain metals or oxides that kill microbes, but this approach can fail when a layer of dead microbes builds up on the surface and allows biofilm to form above it. But this was not the case with the liquid-infused surface that performed well in the ISS experiments: Rather than killing the microbes, it prevented them from adhering to the surface in the first place.

The specific surface used was made of silicon that was etched to produce a nanoscale forest of pillars. This spiky surface is then infused with a silicon oil, which is drawn into the texture and held in place by capillary action, leaving a smooth and highly slippery surface that significantly reduces the adhesion of microbes and prevents them from forming a biofilm.

Identical experiments were conducted on Earth as well as on the space station to determine the differences produced by the microgravity environment in orbit. To the researchers' surprise, the liquid-infused surface performed even better in space than it did on Earth at preventing microbial adhesion.

On previous and current space stations, including the USSR's Mir station, Salyut 6, and Salyut 7, as well as the International Space Station, "they've seen these biofilms, and they jeopardize a variety of instruments or equipment, including space suits, recycling units, radiators, and water treatment facilities, so it's a very important problem that needed to be understood," says Varanasi, a professor of mechanical engineering and founder of a company called LiquiGlide, which makes liquid-impregnated surfaces for containers to help their contents slide out.

Previous tests on Earth had shown that these treated surfaces could significantly reduce biofilm adhesion. When the samples from the space station were retrieved and tested, "we found that these surfaces are extremely good at preventing biofilm formation in the space station as well," Varanasi says. This is important because past work has found that microgravity can have a significant influence on biofilm morphologies, attachment behavior, and gene expression, according to McBride. Thus, strategies that work well on Earth for biofilm mitigation may not necessarily be applicable to microgravity situations.

Preventing biofilms will be especially important for future long-duration missions, such as to the moon or Mars, where the option of quickly returning fouled equipment or sick astronauts to Earth will not be available, the team says. If further testing confirms its long-term stability and successful biofilm prevention, coatings based on the liquid-treated surface concept could be applied to a variety of critical components that are known to be susceptible to biofilm fouling, such as water treatment hoses and filters, or to parts that come in close contact with astronauts, such as gloves or food preparation surfaces.

In the terrestrial samples, biofilm formation was reduced by about 74 percent, while the space station samples showed a reduction of about 86 percent, says Flores, who did much of the testing of the ISS-exposed samples. "The results we got were surprising," she says, because earlier tests carried out by others had shown biofilm formation was actually greater in space than on Earth. "We actually found the opposite on these samples," she says.

While the tests used a specific and well-studied gram-negative kind of bacteria, she says, the results should apply to any kind of gram-negative bacteria, and likely to gram-positive bacteria as well. They found that the areas of the surface where no bacterial growth took place were covered by a thin layer of nucleic acids, which have a slight negative electric charge that may have helped to prevent microbes from adhering. Both gram-positive and gram-negative bacteria have a slight negative charge, which could repel them from that negatively charged surface, Flores says.

Other types of anti-fouling surfaces, Varanasi says, "work mostly on a biocidal property, which usually only works for a first layer of cells because after those cells die they can form a deposit, and microbes can grow on top of them. So, usually it's been a very hard problem." But with the liquid-impregnated surface, where what is exposed is mostly just the liquid itself, there are very few defects or points where the bacteria can find a footing, he says.

Although the test material was on the space station for more than a year, the actual tests were only performed over a three-day period because they required active participation by the astronauts whose schedules are always very busy. But one recommendation the team has made, based on these initial results, is that longer-duration tests should be carried out on a future mission. In these first tests, Flores says, the results after the third day looked the same as after the first and second days. "We don't know for how long it will be able to keep up this performance, so we definitely recommend a longer time of incubation, and also, if possible, a continuous analysis, and not just end points."

Zea, who initiated the project with NASA, says that this was the first time the agency has conducted tests that involved joint participation by two of its science programs, biology and physical sciences. "I think it stresses the importance of multidisciplinarity because we need to be able to combine these different disciplines to find solutions to real world problems."

Biofilms are also a significant medical issue on Earth, especially on medical devices or implants including catheters, where they can lead to significant disease problems. The same kind of liquid-impregnated surfaces may have a role to play in helping to address these issues, Varanasi says.

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A finer picture of global migration reveals complex patterns

While public discussions often focus on climate change driving people to emigrate, new research published in Nature Human Behaviour shows that net-migration patterns around the world are actually more strongly linked with socio-economic factors. The study also provides a new, high-resolution dataset of net-migration over the past two decades to inform policy-making and fuel further research.

'Our findings don't really match the narrative that's repeated by the public about climate-induced migration,' says Venla Niva, a postdoctoral researcher at Aalto University who was lead author of the study. 'When you look at the different factors together, the analysis shows that human development factors are more important drivers than climate.'

Societal factors override climate considerations

The research group, which included researchers from Aalto University, International Institute for Applied Systems Analysis and the University of Bologna, published similar research last year covering the period 1990-2000. The new analysis covers the past two decades, 2000-2019. The high-resolution dataset they prepared makes it possible to answer questions that can't be addressed with coarser data, such as national averages. 'There was a real need for a dataset like this, but it didn't exist. So we decided to make it ourselves,' says Niva. The new dataset is openly available and can be easily explored through an online interactive map.

The team combined birth and death rates with overall population growth to estimate net migration. The role of socio-economics and climate were incorporated through the Human Development Index (HDI) and the aridity index.

By starting with sub-national death and birth ratios and scaling them down to 10 km resolution, the researchers produced a net-migration dataset of unprecedented resolution. This makes it possible to address questions that can't be answered using national aggregates. 'Climate factors don't follow administrative boundaries, so data like this is needed if you want to study these patterns,' explains Niva.

The researchers found high levels of emigration in regions that were on the middle of the scale in both HDI and aridity, such as areas in Central America, northeast Brazil, Central Africa and southeast Asia. 'It's not the poorest of the poor who are fleeing environmental disasters or environmental changes. Migration is an adaptation method used by people who have the capacity to move,' says Niva.

By the same token, areas with a high HDI experienced positive net migration regardless of their climate condition. For example, regions in the Arabian Peninsula, North America, Australia, and the North Mediterranean are net receivers despite their aridity.

'Decision-makers should pay attention to this. Rather than focusing solely on border closures and combating migration, we should work to support and empower individuals in economically disadvantaged countries. That would help reduce the drivers that compel people to migrate in search of better opportunities,' says Matti Kummu, associate professor of global water and food issues at Aalto and senior author of the study.

National averages mask local patterns

The granularity of the new dataset reveals complexities in migration patterns that are hidden when national data is used. 'In France and Italy, for example, there are really interesting differences between north and south, and in Spain there's an east-west difference. There are so many patterns that national experts could look into, and of course the reasons behind them might be different for each country,' says Kummu.

Unexpected patterns also showed up in urban-rural migration. 'There's a very common belief that urban areas are pulling the people from the rural areas, but that wasn't the case everywhere. For example, there are a lot of places for example in Europe where the opposite is true,' says Kummu. Migration from cities to rural areas was also evident in parts of Indonesia, Congo, Venezuela, and Pakistan, and when the analysis is done of the level of communities, the picture becomes even more complex.

'Overall, migration is more complex than people tend to think,' says Niva. 'Our findings contribute to the discussion of where and how migration is happening -- it's not actually a Eurocentric phenomenon, because most migration happens elsewhere in the world.'

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Where is the love? Musical recognition crosses cultures — with an exception

Music can take on many forms in cultures across the globe, but Yale researchers have found in a new study that some themes are universally recognizable by people everywhere with one notable exception -- love songs.

"All around the world, people sing in similar ways," said senior author Samuel Mehr, who splits his time between the Yale Child Study Center, where he is an assistant professor adjunct, and the University of Auckland, where he is senior lecturer in psychology. "Music is deeply rooted in human social interaction."

For the new study, published Sept. 7 in the journal Proceedings of the National Academy of Sciences, Yale researchers played 14-second snippets of vocals from a bank of songs that originated from a host of cultures to more than 5,000 people from 49 countries. The research team included subjects not only from the industrialized world, but more than 100 individuals who live in three small, relatively isolated groups of no more than 100.

They then asked the listeners to rank the likelihood of each sample as being one of four music types: dance, lullabies, "healing" music, or love music.

Unlike most psychology experiments, which are conducted in one language, this experiment was performed in 31 languages. Yet regardless of the language used in the survey, people from all cultures could easily identify dance music, lullabies, and, to a lesser extent, even music created to heal. Recognition of what the researchers identified as love songs, however, lagged these other categories.

For instance, when we they analyzed responses based on language groupings, they found that 27 of the 28 groups correctly rated dance songs as more appropriate for dancing than other songs. All 28 of the groups were able to identify lullabies. But only 12 of the 28 groups were able to identify love songs.

Why the difficulty in identifying musical themes about love?

"One reason for this could be that love songs may be a particularly fuzzy category that includes songs that express happiness and attraction, but also sadness and jealousy," said lead author Lidya Yurdum, who works as research assistant at the Yale Child Study Center and is also a graduate student at the University of Amsterdam. "Listeners who heard love songs from neighboring countries and in languages related to their own actually did a little better, likely because of the familiar linguistic and cultural clues."

But other than love songs, the authors discovered, the listeners' "ratings were largely accurate, consistent with one another, and not explained by their linguistic or geographical proximity to the singer -- showing that musical diversity is underlain by universal psychological phenomena."

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'Brainless' robot can navigate complex obstacles

Researchers who created a soft robot that could navigate simple mazes without human or computer direction have now built on that work, creating a "brainless" soft robot that can navigate more complex and dynamic environments.

"In our earlier work, we demonstrated that our soft robot was able to twist and turn its way through a very simple obstacle course," says Jie Yin, co-corresponding author of a paper on the work and an associate professor of mechanical and aerospace engineering at North Carolina State University. "However, it was unable to turn unless it encountered an obstacle. In practical terms this meant that the robot could sometimes get stuck, bouncing back and forth between parallel obstacles.

"We've developed a new soft robot that is capable of turning on its own, allowing it to make its way through twisty mazes, even negotiating its way around moving obstacles. And it's all done using physical intelligence, rather than being guided by a computer."

Physical intelligence refers to dynamic objects -- like soft robots -- whose behavior is governed by their structural design and the materials they are made of, rather than being directed by a computer or human intervention.

As with the earlier version, the new soft robots are made of ribbon-like liquid crystal elastomers. When the robots are placed on a surface that is at least 55 degrees Celsius (131 degrees Fahrenheit), which is hotter than the ambient air, the portion of the ribbon touching the surface contracts, while the portion of the ribbon exposed to the air does not. This induces a rolling motion; the warmer the surface, the faster the robot rolls.

However, while the previous version of the soft robot had a symmetrical design, the new robot has two distinct halves. One half of the robot is shaped like a twisted ribbon that extends in a straight line, while the other half is shaped like a more tightly twisted ribbon that also twists around itself like a spiral staircase.

This asymmetrical design means that one end of the robot exerts more force on the ground than the other end. Think of a plastic cup that has a mouth wider than its base. If you roll it across the table, it doesn't roll in a straight line -- it makes an arc as it travels across the table. That's due to its asymmetrical shape.

"The concept behind our new robot is fairly simple: because of its asymmetrical design, it turns without having to come into contact with an object," says Yao Zhao, first author of the paper and a postdoctoral researcher at NC State. "So, while it still changes directions when it does come into contact with an object -- allowing it to navigate mazes -- it cannot get stuck between parallel objects. Instead, its ability to move in arcs allows it to essentially wiggle its way free."

The researchers demonstrated the ability of the asymmetrical soft robot design to navigate more complex mazes -- including mazes with moving walls -- and fit through spaces narrower than its body size. The researchers tested the new robot design on both a metal surface and in sand.

"This work is another step forward in helping us develop innovative approaches to soft robot design -- particularly for applications where soft robots would be able to harvest heat energy from their environment," Yin says.

Read more at Science Daily