Engineers bring efficient optical neural networks into focus

EPFL researchers have published a programmable framework that overcomes a key computational bottleneck of optics-based artificial intelligence systems. In a series of image classification experiments, they used scattered light from a low-power laser to perform accurate, scalable computations using a fraction of the energy of electronics.

As digital artificial intelligence systems grow in size and impact, so does the energy required to train and deploy them -- not to mention the associated carbon emissions. Recent research suggests that if current AI server production continues at its current pace, their annual energy consumption could outstrip that of a small country by 2027. Deep neural networks, inspired by the architecture of the human brain, are especially power-hungry due to the millions or even billions of connections between multiple layers of neuron-like processors.

To counteract this mushrooming energy demand, researchers have doubled down on efforts to implement optical computing systems, which have existed experimentally since the 1980s. These systems rely on photons to process data, and although light can theoretically be used to perform computations much faster and more efficiently than electrons, a key challenge has hindered optical systems' ability to surpass the electronic state-of-the art.

"In order to classify data in a neural network, each node, or 'neuron', must make a 'decision' to fire or not based on weighted input data. This decision leads to what is known as a nonlinear transformation of the data, meaning the output is not directly proportional to the input," says Christophe Moser, head of the Laboratory of Applied Photonics Devices in EPFL's School of Engineering.

Moser explains that while digital neural networks can easily perform nonlinear transformations with transistors, in optical systems, this step requires very powerful lasers. Moser worked with students Mustafa Yildirim, Niyazi Ulas Dinc, and Ilker Oguz, as well as Optics Laboratory head Demetri Psaltis, to develop an energy-efficient method for performing these nonlinear computations optically. Their new approach involves encoding data, like the pixels of an image, in the spatial modulation of a low-power laser beam. The beam reflects back on itself several times, leading to a nonlinear multiplication of the pixels.

"Our image classification experiments on three different datasets showed that our method is scalable, and up to 1,000 times more power-efficient than state-of-the-art deep digital networks, making it a promising platform for realizing optical neural networks," says Psaltis.

The research, supported by a Sinergia grant from the Swiss National Science Foundation, has recently been published in Nature Photonics.

A simple structural solution

In nature, photons do not directly interact with each other the way charged electrons do. To achieve nonlinear transformations in optical systems, scientists have therefore had to 'force' photons to interact indirectly, for example by using a light intense enough to modify the optical properties of the glass or other material it passes through.

The scientists worked around this need for a high-power laser with an elegantly simple solution: they encoded the pixels of an image spatially on the surface of a low-power laser beam. By performing this encoding twice, via adjustment of the trajectory of the beam in the encoder, the pixels are multiplied by themselves, i.e., squared. Since squaring is a non-linear transformation, this structural modification achieves the non-linearity essential to neural network calculations, at a fraction of the energy cost. This encoding can be carried out two, three or even ten times, increasing the non-linearity of the transformation and the precision of the calculation.

"We estimate that using our system, the energy required to optically compute a multiplication is eight orders of magnitude less than that required for an electronic system," Psaltis says.

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3D-printed blood vessels bring artificial organs closer to reality

Growing functional human organs outside the body is a long-sought "holy grail" of organ transplantation medicine that remains elusive. New research from Harvard's Wyss Institute for Biologically Inspired Engineering and John A. Paulson School of Engineering and Applied Science (SEAS) brings that quest one big step closer to completion.

A team of scientists created a new method to 3D print vascular networks that consist of interconnected blood vessels possessing a distinct "shell" of smooth muscle cells and endothelial cells surrounding a hollow "core" through which fluid can flow, embedded inside a human cardiac tissue. This vascular architecture closely mimics that of naturally occurring blood vessels and represents significant progress toward being able to manufacture implantable human organs. The achievement is published in Advanced Materials.

"In prior work, we developed a new 3D bioprinting method, known as "sacrificial writing in functional tissue" (SWIFT), for patterning hollow channels within a living cellular matrix. Here, building on this method, we introduce coaxial SWIFT (co-SWIFT) that recapitulates the multilayer architecture found in native blood vessels, making it easier to form an interconnected endothelium and more robust to withstand the internal pressure of blood flow," said first author Paul Stankey, a graduate student at SEAS in the lab of co-senior author and Wyss Core Faculty member Jennifer Lewis, Sc.D.

The key innovation developed by the team was a unique core-shell nozzle with two independently controllable fluid channels for the "inks" that make up the printed vessels: a collagen-based shell ink and a gelatin-based core ink. The interior core chamber of the nozzle extends slightly beyond the shell chamber so that the nozzle can fully puncture a previously printed vessel to create interconnected branching networks for sufficient oxygenation of human tissues and organs via perfusion. The size of the vessels can be varied during printing by changing either the printing speed or the ink flow rates.

To confirm the new co-SWIFT method worked, the team first printed their multilayer vessels into a transparent granular hydrogel matrix. Next, they printed vessels into a recently created matrix called uPOROS composed of a porous collagen-based material that replicates the dense, fibrous structure of living muscle tissue. They were able to successfully print branching vascular networks in both of these cell-free matrices. After these biomimetic vessels were printed, the matrix was heated, which caused collagen in the matrix and shell ink to crosslink, and the sacrificial gelatin core ink to melt, enabling its easy removal and resulting in an open, perfusable vasculature.

Moving into even more biologically relevant materials, the team repeated the printing process using a shell ink that was infused with smooth muscle cells (SMCs), which comprise the outer layer of human blood vessels. After melting out the gelatin core ink, they then perfused endothelial cells (ECs), which form the inner layer of human blood vessels, into their vasculature. After seven days of perfusion, both the SMCs and the ECs were alive and functioning as vessel walls -- there was a three-fold decrease in the permeability of the vessels compared to those without ECs.

Finally, they were ready to test their method inside living human tissue. They constructed hundreds of thousands of cardiac organ building blocks (OBBs) -- tiny spheres of beating human heart cells, which are compressed into a dense cellular matrix. Next, using co-SWIFT, they printed a biomimetic vessel network into the cardiac tissue. Finally, they removed the sacrificial core ink and seeded the inner surface of their SMC-laden vessels with ECs via perfusion and evaluated their performance.

Not only did these printed biomimetic vessels display the characteristic double-layer structure of human blood vessels, but after five days of perfusion with a blood-mimicking fluid, the cardiac OBBs started to beat synchronously -- indicative of healthy and functional heart tissue. The tissues also responded to common cardiac drugs -- isoproterenol caused them to beat faster, and blebbistatin stopped them from beating. The team even 3D-printed a model of the branching vasculature of a real patient's left coronary artery into OBBs, demonstrating its potential for personalized medicine.

"We were able to successfully 3D-print a model of the vasculature of the left coronary artery based on data from a real patient, which demonstrates the potential utility of co-SWIFT for creating patient-specific, vascularized human organs," said Lewis, who is also the Hansjörg Wyss Professor of Biologically Inspired Engineering at SEAS.

In future work, Lewis' team plans to generate self-assembled networks of capillaries and integrate them with their 3D-printed blood vessel networks to more fully replicate the structure of human blood vessels on the microscale and enhance the function of lab-grown tissues.

Read more at Science Daily

Detecting climate change using aerosols

Researchers analyzed long-term aerosol satellite observation big data focusing on the Pacific Ocean downwind of China. Using a newly developed metric that considered aerosols as tracers, they detected altered atmospheric transport patterns associated with climate change. They observed that the distance of transboundary air pollution moving east from China had shortened. Thus, long-term satellite-based Earth observations are crucial for early climate change detection and accurate evaluation of this trend.

Climate change is one of the most significant environmental challenges of present times, leading to extreme weather events, including droughts, forest fires, and floods. The primary driver for climate change is the release of greenhouse gases into the atmosphere due to human activities, which trap heat and raise Earth's temperature. Aerosols (such as particulate matter, PM2.5) not only affect public health but also influence the Earth's climate by absorbing and scattering sunlight and altering cloud properties. Although future climate change predictions are being reported, it is possible that the impacts of climate change could be more severe than predicted. Therefore, it is necessary to detect climate change accurately and as early as possible.

Building on these insights, a research team from Japan, led by Professor Hitoshi Irie from the Center for Environmental Remote Sensing at Chiba University, utilized long-term observational data to study the effect of climate change on transboundary air pollution in the downwind area of China by using aerosols. They utilized a completely unique perspective on how aerosols impact climate and developed a new metric to detect climate change by considering aerosols as tracers.

"The significance of this study lies in the fact that most of its results are derived from observational data. In natural sciences focused on Earth studies, the ultimate goal is to piece together highly accurate data obtained from observations to quantitatively understand the processes occurring on Earth and to pursue immutable truths. Therefore, the more observational data we have, the better. With the continued Earth observations by Japan's major Earth observation satellites (such as the GCOM series, GOSAT series, Himawari series, and ALOS series), we aim to complement these efforts with numerical simulations and data science methodologies to achieve a safe and secure global environment that mitigates the impacts of the climate crisis." explains Prof. Irie.

The research team included Ms. Ying Cai from the Graduate School of Science and Engineering, Chiba University, Dr. Alessandro Damiani from the Center for Climate Change Adaptation, National Institute for Environmental Studies, Dr. Syuichi Itahashi and Professor Toshihiko Takemura from the Research Institute for Applied Mechanics, Kyushu University, and Dr. Pradeep Khatri from Faculty of Science and Engineering, Soka University. Their study was made available online on May 23, 2024, and published in Science of The Total Environment on August 20, 2024.

China is a major contributor to air pollution in East Asia. The downwind area of China analyzed in this study is a unique open ocean area with minimal human interference yet an important zone of transboundary air pollution pathways, making it an ideal location for studying meteorological variations due to climate change.

In their study, the researchers analyzed aerosol optical depth (AOD) datasets derived from satellites, reanalysis datasets, and numerical simulations focused on the Pacific Ocean in the downwind area of China, over 19 years from 2003 to 2021. AOD, a measure of the amount of sunlight blocked by aerosols, is a key factor is analyzing aerosols and their impact on climate change.

The researchers developed a new metric called RAOD which utilized the potential of aerosols as tracers to evaluate the impact of climate change on transboundary air pollution pathways. Using RAOD the researchers were able to quantify significant temporal variations in aerosol transport. They discovered that long-term changes in RAOD due to climate change were outweighed by larger year-to-year variations in the meteorological field. Moreover, seasonal trends showed that aerosols moved west to east during spring and winter, and northward in summer. They concluded that the probability of aerosols from China to be transported far eastward was low, highlighting a shift in transboundary pollution pathways due to global warming. In this study the authors successfully detected climate change using long-term satellite observational data, in contrast to most existing studies that tracked transboundary air pollution using model simulations.

"These results suggest that RAOD is a valuable metric for quantifying the long-term changes in transboundary air pollution pathways due to climate change. These results are particularly significant because most of them are derived from observational data," says Prof. Irie, highlighting the importance of the study. Sharing the future implications of their study he concludes, "The effects of climate change could be more severe than currently predicted. This study will help verify climate change predictions from an unconventional perspective of 'aerosol observation,' enabling a more accurate understanding of climate change progression and implementation of rational countermeasures."

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Early mammals lived longer

What distinguishes the growth and development patterns of early mammals of the Jurassic period? This is the question jointly investigated by researchers of Queen Mary University of London and the University of Bonn. Paleontologists have been able to gauge the lifespan and growth rates of these ancient animals, and even when they reached sexual maturity, by studying growth rings in fossilized tooth roots. The study has now been published in the journal Science Advances.

"Never before have we been able to reconstruct the growth patterns of these early mammals in such detail," says lead author Dr. Elis Newham, a postdoc at Queen Mary University of London who during the study was an Alexander von Humboldt Research Fellow at the University of Bonn, up to March 31, 2024.

For the study, the team analyzed fossilized tooth roots of mammal species from the Early to Late Jurassic periods (200-150 million years ago) found at three separate sites. The finds made in Wales are of some of the oldest known mammalian precursors from the Early Jurassic period, while the fossils found in Oxfordshire, UK are of a very broad array of coexisting early mammals. The fossils from the third site in Portugal date from the Late Jurassic.

Fossil tooth roots X-rayed

The research team studied the fossils using a technique called synchrotron X-ray tomography in which electrons are accelerated to near light speed (unlike regular X-ray imaging). The technique affords several advantages, starting with the fact that the fossils no longer have to be prepared, i.e. cut up into slices, so they can be analyzed whole. Furthermore, images obtained via synchrotron X-ray tomography are of higher quality than images from conventional X-ray microtomography.

Researchers were able to image tiny growth rings in fossilized root cement -- the bone tissue that attaches the teeth to the jaw. "The rings are similar to those in trees, but on a microscopic level," explains Professor Thomas Martin of the Vertebrates -- Mammals working group at the University of Bonn Institute of Organismic Biology, who is a senior author of the study. "Counting the rings and analyzing their thickness and texture enabled us to reconstruct the growth patterns and lifespans of these extinct animals."

The researchers determined that the first signs of the growth patterns characteristic of modern mammals, such as a puberty growth spurt, started emerging roughly 150 million years ago. Early mammals grew much more slowly but lived substantially longer than today's small mammals, with lifespans of eight to fourteen years instead of just one or two as in modern mice, for example. However, it took early mammals years to reach sexual maturity, again in contrast to their modern descendants which reach sexual maturity in just a few months.

"Our findings suggest that the distinctive life history patterns of mammals, characterized by high metabolic rates and extended parental care phases for example, have evolved over millions of years," Dr. Elis Newham explains, "The Jurassic period appears to have been a crucial time for this shift."

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Record-breaking recovery of rocks that originated in Earth's mantle could reveal secrets of planet's history

Scientists have recovered the first long section of rocks that originated in the Earth's mantle, the layer below the crust and the planet's largest component.

The rocks will help unravel the mantle's role in the origins of life on Earth, the volcanic activity generated when it melts, and how it drives the global cycles of important elements such as carbon and hydrogen, according to the team.

The nearly continuous 1,268 metres of mantle rock was recovered from a "tectonic window," a section of the seabed where rocks from the mantle were exposed along the Mid-Atlantic Ridge, during Expedition 399 "Building Blocks of Life, Atlantis Massif" of the ocean drilling vessel JOIDES Resolution in Spring 2023.

With attempts dating back to the early 1960s, the recovery was a record-breaking achievement led by the International Ocean Discovery Program, an international marine research consortium of more than 20 countries that retrieves cores -- cylindrical samples of sediment and rock -- from the ocean floor to study Earth's history.

Since then, the expedition team has been compiling an inventory of the recovered mantle rocks to understand their composition, structure and context.

Their findings, presented in the journal Science, reveal a more extensive history of melting in the recovered rocks than expected.

Lead author Professor Johan Lissenberg from Cardiff University's School of Earth and Environmental Sciences, said: "When we recovered the rocks last year, it was a major achievement in the history of the Earth sciences, but, more than that, its value is in what the cores of mantle rocks could tell us about the makeup and evolution of our planet.

"Our study begins to look at the composition of the mantle by documenting the mineralogy of the recovered rocks, as well as their chemical makeup.

"Our results differ from what we expected. There is a lot less of the mineral pyroxene in the rocks, and the rocks have got very high concentrations of magnesium, both of which results from much higher amounts of melting than what we would have predicted."

This melting occurred as the mantle rose from the deeper parts of the Earth towards the surface.

Results from further analysis of this process could have major implications for the understanding of how magma is formed and leads to volcanism, the researchers claim.

"We also found channels through which melt was transported through the mantle, and so we are able to track the fate of magma after it is formed and travels upwards to the Earth's surface.

"This is important because it tells us how the mantle melts and feeds volcanoes, particularly those on the ocean floor that account for the majority of volcanism on Earth. Having access to these mantle rocks will allow us to make the connection between the volcanoes and the ultimate source of their magmas."

The study also provides initial results on how olivine, an abundant mineral in mantle rocks, reacts with seawater, leading to a series of chemical reactions that produce hydrogen and other molecules that can fuel life.

Scientists believe this might have been one of the underpinning processes in the origin of life on Earth.

Dr Susan Q Lang, an associate scientist in Geology and Geophysics at the Woods Hole Oceanographic Institution, who was a co-chief scientist on the expedition and part of a team continuing to analyse rock and fluid samples, said: "The rocks that were present on early Earth bear a closer resemblance to those we retrieved during this expedition than the more common rocks that make up our continents today.

"Analysing them gives us a critical view into the chemical and physical environments that would have been present early in Earth's history, and that could have provided a consistent source of fuel and favorable conditions over geologically long timeframes to have hosted the earliest forms of life."

The international team of more than 30 scientists from the JOIDES Resolution expedition will continue their research on the recovered drill cores to address a wide range of problems.

Read more at Science Daily

Scientists lay out revolutionary method to warm Mars

Ever since we learned that the surface of planet Mars is cold and dead, people have wondered if there is a way to make it friendlier to life.

In a groundbreaking study published Aug. 7 in Science Advances, researchers from the University of Chicago, Northwestern University, and the University of Central Florida have proposed a revolutionary approach towards terraforming Mars. This new method, using engineered dust particles released to the atmosphere, could potentially warm the Red Planet by more than 50 degrees Fahrenheit, to temperatures suitable for microbial life -- a crucial first step towards making Mars habitable.

The proposed method is over 5,000 times more efficient than previous schemes to globally warm Mars, representing a significant leap forward in our ability to modify the Martian environment.

What sets this approach apart is its use of resources readily available on Mars, making it far more feasible than earlier proposals that relied on importing materials from Earth or mining rare Martian resources.

This strategy would take decades. But it appears logistically easier than other plans proposed so far.

"This suggests that the barrier to warming Mars to allow liquid water is not as high as previously thought," said Edwin Kite, an associate professor of geophysical sciences at the University of Chicago and corresponding author on the study. The lead author was Samaneh Ansari, a graduate student in Prof. Hooman Mohseni's group at Northwestern University.

Astronauts still won't be able to breathe Mars' thin air; making the planet suitable for humans to walk on the surface unaided requires much more work. But perhaps groundwork could be laid, by making the planet habitable for microbes and food crops that could gradually add oxygen to the atmosphere -- much as they have done for Earth during its geologic history.

A new approach to an age-old dream

There is a rich history of proposals to make Mars habitable; Carl Sagan himself came up with one back in 1971. These have ranged from outright daydreams, such as science fiction writers depicting turning one of Mars' moons into a sun, to more recent and scientifically plausible ideas, such as engineering transparent gel tiles to trap heat.

Any plan to make Mars habitable must address several hurdles, including deadly UV rays and salty soil. But the biggest is the planet's temperature; the surface of Mars averages about -80 degrees Fahrenheit.

One strategy to warm the planet could be the same method that humans are unintentionally using here on Earth: releasing material into the atmosphere, which would enhance Mars' natural greenhouse effect, trapping solar heat at the surface.

The trouble is that you would need tons of these materials -- literally. Previous schemes depended on bringing gases from Earth to Mars, or attempting to mine Mars for a large mass of ingredients that aren't very common there -- both are costly and difficult propositions. But the team wondered whether it could be done by processing materials that already exist abundantly on Mars.

We know from rovers like Curiosity that dust on Mars is rich in iron and aluminum. By themselves, those dust particles aren't suitable to warm the planet; their size and composition mean they tend to cool the surface slightly rather than warm it. But if we engineered dust particles that had different shapes or compositions, the researchers hypothesized, perhaps they could trap heat more efficiently.

The researchers designed particles shaped like short rods -- similar in size to commercially available glitter. These particles are designed to trap escaping heat and scatter sunlight towards the surface, enhancing Mars' natural greenhouse effect.

"How light interacts with sub-wavelength objects is fascinating. Importantly, engineering

nanoparticles can lead to optical effects that far exceed what is conventionally expected from

such small particles," said Ansari. Mohseni, who is a co-author, believes that they have just scratched the surface: "We believe it is possible to design nanoparticles with higher efficiency, and even those that can dynamically change their optical properties."

"You'd still need millions of tons to warm the planet, but that's five thousand times less than you would need with previous proposals to globally warm Mars," said Kite. "This significantly increases the feasibility of the project."

Calculations indicate that if the particles were released into Mars' atmosphere continuously at 30 liters per second, the planet would warm by more than 50 degrees Fahrenheit -- and the effect could be noticeable within as soon as months. Similarly, the warming would be reversible, stopping within a few years if release was switched off.

Potential impact and future research

Much work remains to be done, the scientists said. We don't know exactly how fast the engineered dust would cycle out of Mars' atmosphere, for example. Mars does have water and clouds, and, as the planet warms, it's possible that water would increasingly start to condense around the particles and fall back to the surface as rain.

"Climate feedbacks are really difficult to model accurately," Kite cautioned. "To implement something like this, we would need more data from both Mars and Earth, and we'd need to proceed slowly and reversibly to ensure the effects work as intended."

While this method represents a significant leap forward in terraforming research, the researchers emphasize that the study focuses on warming Mars to temperatures suitable for microbial life and possibly growing food crops -- not on creating a breathable atmosphere for humans.

"This research opens new avenues for exploration and potentially brings us one step closer to the long-held dream of establishing a sustainable human presence on Mars," said Kite.

Read more at Science Daily

New report on Great Barrier Reef shows coral cover increases before onset of serious bleaching, cyclones

Coral cover has increased in all three regions on the Great Barrier Reef and is at regional highs in two of the three regions, according to a report by the Australian Institute of Marine Science (AIMS). But the results come with a note of caution.

Most of the underwater surveys contributing to these findings published today, were conducted before and during the recent mass bleaching event, one of the most extensive and serious on record, and have not yet captured how many corals survived or died following the bleaching.    

Surveys in the Central region were also completed before the passage of tropical Cyclone Jasper in December 2023.    

AIMS' Long-Term Monitoring Program (LTMP) leader Dr Mike Emslie said coral cover increases were a positive sign but did not reflect the potentially destructive consequences of the 2024 mass bleaching event. 

"We saw evidence of early onset mortality, particularly in the Southern region, but the full picture of mortality was not yet apparent during this year's surveys," he said.

"While bleached corals are very stressed, they are still alive and are recorded as live coral on our surveys. 

"Some types of corals can remain bleached for months, remaining on a knife edge between survival and death. This is why returning and repeating surveys of the reefs in this vast, complex and dynamic system is so important. This year's results serve as a very important reference against which to measure the impacts of the summer's events."

The next (LTMP) survey season recommences in September and will capture impacts on coral cover from this summer's mass bleaching event and the cyclones, with a full assessment complete by mid-2025.  

"Climate change remains the greatest threat to the Reef because it drives these mass bleaching events. This most recent one was the fifth such event since 2016. These more frequent and extensive marine heatwaves will lead to shortened 'windows' for coral recovery. Recent gains, while encouraging, can be lost in a short amount of time," Dr Emslie said.

Surveys were conducted at 94 Reefs spread through the Northern, Central and Southern Great Barrier Reef between August 2023 and June 2024.    

The Report recorded the following average hard coral coverage:    

•     Northern region (north of Cooktown) -- 39.5%, up from 35.8% last year;    
•     Central region (Cooktown to Proserpine) -- 34%, up from 30.7%;   
•     Southern region (south of Proserpine) -- 39.1%, up from 34%.   

The AIMS report finds that small rises in coral cover this year bring the Northern and Central regions to their highest levels in 38 years of monitoring.  

The surveys also found that crown-of-thorns starfish outbreaks have persisted on some reefs in the Southern region.    

The long term monitoring team surveyed reefs off Townsville after the passage of tropical Cyclone Kirrily in late January, finding evidence of storm damage and declines in hard coral cover ranging from 6% to 10% at Kelso, John Brewer, Helix and Chicken Reefs. Other reefs appear to have escaped with little impact.    

AIMS Research Program Director Dr David Wachenfeld said the regional increases in coral cover are encouraging, showing the Reef's capacity for recovery after reaching their lowest levels within the last 15 years. However, climate change and other disturbances mean this recovery is fragile and Reef resilience is not limitless.    

"In many ways the Reef has had some lucky escapes in recent years. The 2020 and 2022 mass bleaching events had levels of heat stress that were not as intense as the 2016 and 2017 events or the 2024 event. Coupled with very few other events causing widespread coral death, that has led to the levels of coral cover increase we have seen," he said.   

"But the frequency and intensity of bleaching events is unprecedented, and that is only forecast to escalate under climate change, alongside the persistent threat of crown-of-thorns starfish outbreaks and tropical cyclones."    

Aerial surveys undertaken by AIMS and the Great Barrier Reef Marine Park Authority in February and March found bleached corals in the shallows of 73% of reefs surveyed across all three regions.  

In recent weeks, AIMS scientists in separate monitoring programs observed substantial mortality in reefs that were particularly hard hit by the 2024 event.  

"We are only one large scale disturbance event away from a reversal of the recent recovery. The 2024 bleaching event could be that event -- almost half of the 3000 or so reefs that make up the marine park experienced more heat stress than ever recorded," Dr Wachenfeld said.    

"We still don't know how much mortality this event has caused. Our monitoring over the next 12 months will help us to understand how this bleaching event stacks up against the others in the last decade." 

AIMS CEO Professor Selina Stead said AIMS was prioritising research to develop scientific solutions to boost reef resilience under a warming climate.   

"Climate change is increasing pressure on reef systems around the world," she said.  "The 2024 bleaching event was part of the fourth global bleaching event, announced in April.

"These vitally important ecosystems that millions rely upon need strong greenhouse gas emissions reduction, science-based management of local pressures, and input from multiple fields of research if they are to endure.

"At AIMS we are developing a toolbox of interventions to help reefs adapt to and recover from the effects of climate change."

Read more at Science Daily

Giant prehistoric flying reptile took off using similar method to bats, study finds

The pterosaur likely used all four limbs to propel itself in the air, as seen in bats today, researchers have found.

The findings, published today in PeerJ, provide new insights into how pterosaurs managed to take flight despite reaching sizes far larger than modern animals.

The research sheds new light on the flight initiating jumping ability of these animals, some of which had wingspans of over ten meters.

The study, carried out by scientists at the University of Bristol, Liverpool John Moores University, Universidade Federal do ABC and the University of Keele, follows years of analysis and modelling of how muscles interact with bones to create movement in other animals and is now being used to start answering the question of how the largest flying animals known managed to get off the ground.

The team created the first computer model for this kind of analysis of a pterosaur to test three different ways pterosaurs may have taken off: a vertical burst jump using just the legs like those used by primarily ground-dwelling birds, a less vertical jump using just the legs more similar to the jump used by birds that fly frequently, and a four-limbed jump using its wings as well in a motion more like the take-off jump of a bat.

By mimicking these motions, the researchers aimed to understand the leverage available to push the animal into the air.

"Larger animals have greater challenges to overcome in order to fly making the ability of animals as large as pterosaurs to do so especially fascinating." Dr Ben Griffin, the lead author of the study, said.

"Unlike birds which mainly rely on their hindlimbs, our models indicate that pterosaurs were more likely to rely on all four of their limbs to propel themselves into the air."

Read more at Science Daily

Carvings at ancient monument may be world's oldest calendars

Markings on a stone pillar at a 12,000 year-old archaeological site in Turkey likely represent the world's oldest solar calendar, created as a memorial to a devastating comet strike, experts suggest.

The markings at Göbekli Tepe in southern Turkey -- an ancient complex of temple-like enclosures adorned with intricately carved symbols -- could record an astronomical event that triggered a key shift in human civilisation, researchers say.

The research suggests ancient people were able to record their observations of the sun, moon and constellations in the form of a solar calendar, created to keep track of time and mark the change of seasons.

Fresh analysis of V-shaped symbols carved onto pillars at the site has found that each V could represent a single day. This interpretation allowed researchers to count a solar calendar of 365 days on one of the pillars, consisting of 12 lunar months plus 11 extra days.

The summer solstice appears as a separate, special day, represented by a V worn around the neck of a bird-like beast thought to represent the summer solstice constellation at the time. Other statues nearby, possibly representing deities, have been found with similar V-markings at their necks.

Since both the moon's and the sun's cycles are depicted, the carvings could represent the world's earliest so-called lunisolar calendar, based on the phases of the moon and the position of the sun -- pre-dating other known calendars of this type by many millennia.

Ancient people may have created these carvings at Göbekli Tepe to record the date a swarm of comet fragments hit Earth nearly 13,000 years ago -- or 10,850 BC -- researchers say.

The comet strike is suggested to have ushered in a mini ice age lasting over 1,200 years, wiping out many species of large animals. It could also have triggered changes in lifestyle and agriculture thought to be linked to the birth of civilisation soon afterwards in the fertile crescent of West Asia.

Another pillar at the site appears to picture the Taurid meteor stream -- which is thought to be the source of the comet fragments -- lasting 27 days and emanating from the directions of Aquarius and Pisces.

The find also appears to confirm that ancient people were able to record dates using precession -- the wobble in Earth's axis which affects the movement of constellations across the sky -- at least 10,000 years before the phenomenon was documented by Hipparchus of Ancient Greece in 150 BC.

The carvings appear to have remained important to the people of Göbekli Tepe for millennia, suggesting the impact event may have triggered a new cult or religion that influenced the development of civilisation.

The find also supports a theory that Earth faces increased comet strikes as its orbit crosses the path of circling comet fragments, which we normally experience as meteor streams.

Read more at Science Daily

Astronomers uncover risks to planets that could host life

A groundbreaking study has revealed that red dwarf stars can produce stellar flares that carry far-ultraviolet (far-UV) radiation levels much higher than previously believed. This discovery suggests that the intense UV radiation from these flares could significantly impact whether planets around red dwarf stars can be habitable. Led by current and former astronomers from the University of Hawaii Institute for Astronomy (IfA), the research was recently published in the Monthly Notices of the Royal Astronomical Society.

"Few stars have been thought to generate enough UV radiation through flares to impact planet habitability. Our findings show that many more stars may have this capability," said astronomer Vera Berger, who undertook the study while in the Research Experiences for Undergraduates program at IfA, an initiative supported by the National Science Foundation.

Berger and her team used archival data from the GALEX space telescope to search for flares among 300,000 nearby stars. GALEX is a now-decommissioned NASA mission that simultaneously observed most of the sky at near-and far-UV wavelengths from 2003 to 2013. Using new computational techniques, the team mined novel insights from the data.

"Combining modern computer power with gigabytes of decades-old observations allowed us to search for flares on thousands and thousands of nearby stars," said Michael Tucker, a PhD graduate of IfA and now a postdoctoral fellow at Ohio State University.

UV's double edge

According to researchers, UV radiation from stellar flares can either erode planetary atmospheres, threatening their potential to support life, or contribute to the formation of RNA building blocks, which are essential for the creation of life.

This study challenges existing models of stellar flares and exoplanet habitability, showing that far-UV emission from flares is on average three times more energetic than typically assumed, and can reach up to twelve times the expected energy levels.

"A change of three is the same as the difference in UV in the summer from Anchorage, Alaska to Honolulu, where unprotected skin can get a sunburn in less than 10 minutes," said Benjamin J. Shappee, an Associate Astronomer at IfA who mentored Berger.

Hidden causes

The exact cause of this stronger far-UV emission remains unclear. The team believes it might be that flare radiation is concentrated at specific wavelengths, indicating the presence of atoms like carbon and nitrogen.

"This study has changed the picture of the environments around stars less massive than our Sun, which emit very little UV light outside of flares," said Jason Hinkle, a PhD candidate at IfA who co-authored the study.

Read more at Science Daily