Red-supergiant supernova: Secrets of an earlier Universe

An international research team led by the University of Minnesota Twin Cities has measured the size of a star dating back 2 billion years after the Big Bang, or more than 11 billion years ago. Detailed images show the exploding star cooling and could help scientists learn more about the stars and galaxies present in the early Universe.

The paper is published in Nature, the world's leading peer-reviewed, multidisciplinary science journal.

"This is the first detailed look at a supernova at a much earlier epoch of the Universe's evolution," said Patrick Kelly, a lead author of the paper and an associate professor in the University of Minnesota School of Physics and Astronomy. "It's very exciting because we can learn in detail about an individual star when the Universe was less than a fifth of its current age, and begin to understand if the stars that existed many billions of years ago are different from the ones nearby."

The red supergiant in question was about 500 times larger than the sun, and it's located at redshift three, which is about 60 times farther away than any other supernova observed in this detail.

Using data from the Hubble Space Telescope with follow-up spectroscopy using the University of Minnesota's access to the Large Binocular Telescope, the researchers were able to identify multiple detailed images of the red supergiant because of a phenomenon called gravitational lensing, where mass, such as that in a galaxy, bends light. This magnifies the light emitted from the star.

"The gravitational lens acts as a natural magnifying glass and multiplies Hubble's power by a factor of eight," Kelly said. "Here, we see three images. Even though they can be seen at the same time, they show the supernova as it was at different ages separated by several days. We see the supernova rapidly cooling, which allows us to basically reconstruct what happened and study how the supernova cooled in its first few days with just one set of images. It enables us to see a rerun of a supernova."

The researchers combined this discovery with another one of Kelly's supernova discoveries from 2014 to estimate how many stars were exploding when the Universe was a small fraction of its current age. They found that there were likely many more supernovae than previously thought.

"Core-collapse supernovae mark the deaths of massive, short-lived stars. The number of core-collapse supernovae we detect can be used to understand how many massive stars were formed in galaxies when the Universe was much younger," said Wenlei Chen, first author of the paper and a postdoctoral researcher in the University of Minnesota School of Physics and Astronomy.

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Rats bop to the beat

Accurately moving to a musical beat was thought to be a skill innately unique to humans. However, new research now shows that rats also have this ability. The optimal tempo for nodding along was found to depend on the time constant in the brain (the speed at which our brains can respond to something), which is similar across all species. This means that the ability of our auditory and motor systems to interact and move to music may be more widespread among species than previously thought. This new discovery offers not only further insight into the animal mind, but also into the origins of our own music and dance.

Can you move to the beat, or do you have two left feet? Apparently, how well we can time our movement to music depends somewhat on our innate genetic ability, and this skill was previously thought to be a uniquely human trait. While animals also react to hearing noise, or might make rhythmic sounds, or be trained to respond to music, this isn't the same as the complex neural and motor processes that work together to enable us to naturally recognize the beat in a song, respond to it or even predict it. This is referred to as beat synchronicity.

Only relatively recently, research studies (and home videos) have shown that some animals seem to share our urge to move to the groove. A new paper by a team at the University of Tokyo provides evidence that rats are one of them. "Rats displayed innate -- that is, without any training or prior exposure to music -- beat synchronization most distinctly within 120-140 bpm (beats per minute), to which humans also exhibit the clearest beat synchronization," explained Associate Professor Hirokazu Takahashi from the Graduate School of Information Science and Technology. "The auditory cortex, the region of our brain that processes sound, was also tuned to 120-140 bpm, which we were able to explain using our mathematical model of brain adaptation."

But why play music to rats in the first place? "Music exerts a strong appeal to the brain and has profound effects on emotion and cognition. To utilize music effectively, we need to reveal the neural mechanism underlying this empirical fact," said Takahashi. "I am also a specialist of electrophysiology, which is concerned with electrical activity in the brain, and have been studying the auditory cortex of rats for many years."

The team had two alternate hypotheses: The first was that the optimal music tempo for beat synchronicity would be determined by the time constant of the body. This is different between species and much faster for small animals compared to humans (think of how quickly a rat can scuttle). The second was that the optimal tempo would instead be determined by the time constant of the brain, which is surprisingly similar across species. "After conducting our research with 20 human participants and 10 rats, our results suggest that the optimal tempo for beat synchronization depends on the time constant in the brain," said Takahashi. "This demonstrates that the animal brain can be useful in elucidating the perceptual mechanisms of music."

The rats were fitted with wireless, miniature accelerometers, which could measure the slightest head movements. Human participants also wore accelerometers on headphones. They were then played one-minute excerpts from Mozart's Sonata for Two Pianos in D Major, K. 448, at four different tempos: Seventy-five percent, 100%, 200% and 400% of the original speed. The original tempo is 132 bpm and results showed that the rats' beat synchronicity was clearest within the 120-140 bpm range. The team also found that both rats and humans jerked their heads to the beat in a similar rhythm, and that the level of head jerking decreased the more that the music was sped up.

"To the best of our knowledge, this is the first report on innate beat synchronization in animals that was not achieved through training or musical exposure," said Takahashi. "We also hypothesized that short-term adaptation in the brain was involved in beat tuning in the auditory cortex. We were able to explain this by fitting our neural activity data to a mathematical model of the adaptation. Furthermore, our adaptation model showed that in response to random click sequences, the highest beat prediction performance occurred when the mean interstimulus interval (the time between the end of one stimulus and the start of another) was around 200 milliseconds (one-thousandth of a second). This matched the statistics of internote intervals in classical music, suggesting that the adaptation property in the brain underlies the perception and creation of music."

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A supernova in distant space allows us to understand the origin of the elements in the universe

A supernova is a stellar explosion, which occurs when the lives of some really massive stars come to an end. In this violent epilogue, the star expels the material from its outer layers by means of a shock wave, allowing us to see the various elements it was composed of.

The research team developed a model of the gravitational field of the galaxy that acted as a lens, and that way it was possible to determine that the light from these three images travelled along three different paths, differing in distance by a few days. This accounts for the three colours obtained in the images, because a variation in the colour emitted takes place as the gas in the supernova expands and cools. The higher the temperature is, the bluer the light emitted will be, and as the temperature falls, the light emitted tends towards red. So the blue image is a photograph of the supernova a few hours after the stellar explosion, while the green and red images correspond to 2 and 8 days, respectively, after the explosion.

This information enabled the radius of the star that exploded to be determined; it was a red super-giant with a radius equal to 500 times that of the Sun, and exploded 11.5 billion years ago, long before the Earth was born, specifically at the moment when our Galaxy is thought to have formed. The images of this supernova captured by the Hubble Space Telescope are highly magnified by the gravitational field of a nearby galaxy that acts as a lens and allows us to see much further in distance and in time than all local supernovae in nearby galaxies.

The study of the explosions of these red super-giant stars tallies with the current understanding of how the heavier atomic elements were created inside stars and during supernova explosions: elements forged inside stars are released in these supernova explosions to become the next generation of gas and material from which solar systems and life as we know it are created. Without these explosions, the gas in today's galaxies would only include the hydrogen and helium that formed during the Big Bang and would not support complex life that requires other heavier chemical elements. Moreover, this supernova observed through a gravitational lens demonstrates that an event taking place in the distant Universe can be witnessed several times, so in principle we could focus our instruments in advance to get a detailed view of the eruption of a star turning into a supernova.

From Science Daily

Thirsty wheat needed new water management strategy in ancient China

Research from Washington University in St. Louis shows that a practice of purposeful water management, or irrigation, was adopted in northern China about 4,000 years ago as part of an effort to grow new grains that had been introduced from southwest Asia.

But the story gets more complex from there. Wheat and barley arrived on the scene at about the same time, but early farmers only used water management techniques for wheat. The results, reported Nov. 9 in the journal Antiquity, raise awareness that the dispersal of domesticated crops and the knowledge of best using them can be traced independently across time and space.

"Pioneering farmers who cultivated wheat in this region managed water to meet the higher demand of this newly introduced grain," said Xinyi Liu, an associate professor of archaeology in Arts & Sciences, who collaborated on this study with researchers from several prominent institutions in China and Australia, including Guanghui Dong from Lanzhou University, who led the field expedition on the Loess Plateau. "The water management may have been achieved either by deliberate watering or by strategic planting in soils with higher water retention."

On the other hand, early farmers were able to grow the other new grain, barley, in a rainfed system as if it were just another kind of millet -- the locally domesticated and most commonly grown grain in northern China at the time -- without using any form of irrigation.

Liu published the study with Washington University graduate student Yufeng Sun. Other co-authors include Haiming Li and Petra Vaiglova, former members of Liu's lab group.

Introducing irrigation

Both wheat and barley were domesticated in an area known to archaeologists as the hilly flanks of the Fertile Crescent in southwest Asia, where they originally were grown as winter crops. Traditionally, farmers there sowed their seeds in autumn -- to avoid the summer drought period -- and harvested them in late spring or early summer before the next drought season.

When these Fertile Crescent crops, wheat and barley, were introduced to East Asia about 4,000 years ago, they would have encountered a markedly different climate compared with where they originated.

"Every summer, the East Asian monsoon brings rains from the Pacific Ocean to a region otherwise arid throughout the rest of the year. This environment is perfect for rainfed millet cultivation as these local grains are drought tolerant but need considerable water in the summer growing season," Liu said. "But it is a different story if you try to grow wheat there, not only because it is water demanding, but also the growing cycle doesn't match the rainy season."

Liu and his colleagues wanted to know: Did the farmers who sought to grow the new grains in northern China also introduce new systems of irrigation to support them?

"The introduction of a new irrigation system is something that scholars have speculated about, but now we have the technology to seek direct evidence," Liu said.

Using relatively new techniques, the actual growing conditions of past crops -- including past water and soil conditions during plant growth -- can be measured using the stable carbon and nitrogen isotope compositions of charred plant remains. These methods initially were established in plant science for research concerning environmental conditions of modern-day agriculture and have been subsequently applied to archaeological research.

Previous studies using similar approaches have shed significant light on early crop management in Europe and the Middle East. This research is one of the first attempts to apply it to East Asian monsoon environments with innovative questions.

For this study, the scientists identified more than 35,000 charred seed remains of cereal plants, including wheat, barley and millet, from more than 50 archaeological sites excavated on the Loess Plateau of China spanning a timeframe over eight millennia. Selected plant remains from this collection were radiocarbon dated and isotopically measured.

The results showed major differences between wheat and barley.

Despite the arid local environment, the majority of the wheat samples from all time periods had isotopic values above an optimal watering threshold, indicating that their growth was not limited by water availability.

"We see this in the Qijia culture period, when wheat and barley were just introduced to this region," Liu said. "The isotopic data of wheat show a significant level of water manipulation unambiguously since 4,000 years ago, indicating the new crop was introduced with water management strategies to support it."

Simple ditches can be powerful

This evidence alone does not necessarily imply large-scale irrigation, Liu is quick to point out; instead, wheat crops may have been strategically sown in areas with the best water availability, either close to local springs or in soils with high water retention.

"In those locations, small ditches to diffuse water is sufficient," Liu said. "This explains why there is no archaeological evidence of channels or other irrigation installations in the area until much later."

Barley, on the other hand, appears to have been grown on the dry hills of the Loess Plateau without a special water management approach -- a landscape and cultivation strategy that had been familiar to the Neolithic millet farmers since 8,000 years ago.

This and other evidence suggest to Liu and his collaborators that ancient farmers sought to optimize land use and crop yield by taking advantage of the different water demands of these two crops.

"Our results raise an awareness that the dispersal of domesticated crops and the knowledge of best using them can be traced independently across time and space," Liu said.

"Central to our inquiry is the tension between non-native crops and indigenous farming practices," he said. "When non-native innovations were adopted in another cultural and physical environment, they would have been transformed within the local context. How this happens is an enduring question that is relevant to globalization in the past and present."

This study resonates with other archaeological investigations led by Liu's research group, the Laboratory for the Analysis of Early Food-Webs at Washington University. For example, co-author Sun's previous work with Washington University graduate student Melissa Ritchey demonstrated a similar geographic decoupling of the dispersal of grains and cuisines, such that wheat and barley dispersed into ancient China 4,000 years ago, but the western grinding-and-baking cuisines did not. The eastern movement of these grains involved selections of phenotypic traits adapted to ancient China's cooking tradition of using steaming-and-boiling.

It has been a long time since some scholars assumed the association between the origin of bureaucracy and irrigation, and ancient China had been used as an example of "oriental despotism," according to Liu. The "hydraulic empire" hypothesis speculated that a centralized government structure that maintained power would have been derived from the need for flood control and irrigation.

Read more at Science Daily

No sign of decrease in global CO2 emissions

Global carbon emissions in 2022 remain at record levels -- with no sign of the decrease that is urgently needed to limit warming to 1.5°C, according to the Global Carbon Project science team.

If current emissions levels persist, there is now a 50% chance that global warming of 1.5°C will be exceeded in nine years.

The new report projects total global CO2 emissions of 40.6 billion tonnes (GtCO2) in 2022. This is fuelled by fossil CO2 emissions which are projected to rise 1.0% compared to 2021, reaching 36.6 GtCO2 -- slightly above the 2019 pre-COVID-19 levels[1]. Emissions from land-use change (such as deforestation) are projected to be 3.9 GtCO2 in 2022.

Projected emissions from coal and oil are above their 2021 levels, with oil being the largest contributor to total emissions growth. The growth in oil emissions can be largely explained by the delayed rebound of international aviation following COVID-19 pandemic restrictions.

The 2022 picture among major emitters is mixed: emissions are projected to fall in China (0.9%) and the EU (0.8%), and increase in the USA (1.5%) and India (6%), with a 1.7% rise in the rest of the world combined.

The remaining carbon budget for a 50% likelihood to limit global warming to 1.5°C has reduced to 380 GtCO2 (exceeded after nine years if emissions remain at 2022 levels) and 1230 GtCO2 to limit to 2°C (30 years at 2022 emissions levels).

To reach zero CO2 emissions by 2050 would now require a decrease of about 1.4 GtCO2 each year, comparable to the observed fall in 2020 emissions resulting from COVID-19 lockdowns, highlighting the scale of the action required.

Land and ocean, which absorb and store carbon, continue to take up around half of the CO2 emissions. The ocean and land CO2 sinks are still increasing in response to the atmospheric CO2 increase, although climate change reduced this growth by an estimated 4% (ocean sink) and 17% (land sink) over the 2012-2021 decade.

This year's carbon budget shows that the long-term rate of increasing fossil emissions has slowed. The average rise peaked at +3% per year during the 2000s, while growth in the last decade has been about +0.5% per year.

The research team -- including the University of Exeter, the University of East Anglia (UEA), CICERO and Ludwig-Maximilian-University Munich -- welcomed this slow-down, but said it was "far from the emissions decrease we need."

The findings come as world leaders meet at COP27 in Egypt to discuss the climate crisis.

"This year we see yet another rise in global fossil CO2 emissions, when we need a rapid decline," said Professor Pierre Friedlingstein, of Exeter's Global Systems Institute, who led the study.

"There are some positive signs, but leaders meeting at COP27 will have to take meaningful action if we are to have any chance of limiting global warming close to 1.5°C. The Global Carbon Budget numbers monitor the progress on climate action and right now we are not seeing the action required."

Professor Corinne Le Quéré, Royal Society Research Professor at UEA's School of Environmental Sciences, said: "Our findings reveal turbulence in emissions patterns this year resulting from the pandemic and global energy crises.

"If governments respond by turbo charging clean energy investments and planting, not cutting, trees, global emissions could rapidly start to fall.

"We are at a turning point and must not allow world events to distract us from the urgent and sustained need to cut our emissions to stabilise the global climate and reduce cascading risks."

Land-use changes, especially deforestation, are a significant source of CO2 emissions (about a tenth of the amount from fossil emissions). Indonesia, Brazil and the Democratic Republic of the Congo contribute 58% of global land-use change emissions.

Carbon removal via reforestation or new forests counterbalances half of the deforestation emissions, and the researchers say that stopping deforestation and increasing efforts to restore and expand forests constitutes a large opportunity to reduce emissions and increase removals in forests.

The Global Carbon Budget report projects that atmospheric CO2 concentrations will reach an average of 417.2 parts per million in 2022, more than 50% above pre-industrial levels.

The projection of 40.6 GtCO2 total emissions in 2022 is close to the 40.9 GtCO2 in 2019, which is the highest annual total ever.

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Previously unknown monumental temple discovered near the Tempio Grande in Vulci

An interdisciplinary team headed by archeologists Dr. Mariachiara Franceschini of the University of Freiburg and Paul P. Pasieka of the University of Mainz has discovered a previously unknown Etruscan temple in the ancient city of Vulci, which lies in the Italian region of Latium. The building, which is 45 meters by 35 meters, is situated west of the Tempio Grande, a sacred building which was excavated back in the 1950s. Initial examination of the strata of the foundation of the northeast corner of the temple and the objects they found there, led the researchers to date the construction of the temple towards the end of the sixth or beginning of the fifth century BCE.

"The new temple is roughly the same size and on a similar alignment as the neighboring Tempio Grande, and was built at roughly the same Archaic time," explains Franceschini. "This duplication of monumental buildings in an Etruscan city is rare, and indicates an exceptional finding," adds Pasieka. The team discovered the temple when working on the Vulci Cityscape project, which was launched in 2020 and aimed to research the settlement strategies and urbanistic structures of the city of Vulci. Vulci was one of the twelve cities of the Etruscan federation and in pre-Roman times was one of the most important urban centers in what is now Italy.

New discoveries about city design and development

"We studied the entire northern area of Vulci, that's 22.5 hectares, using geophysical prospecting and Ground Penetrating Radar," explains Pasieka. "We discovered remains from the city's origins that had previously been overlooked in Vulci and are now better able to understand the dynamics of settlement and the road system, besides identifying different functional areas in the city." The researchers were able in 2021 to uncover the first sections of wall, made of solid tuff. "Our knowledge about the appearance and organization of Etruscan cities has been limited until now," says Franceschini. "The intact strata of the temple are offering us insights into more than a thousand years of development of one of the most important Etruscan cities."

Over the coming years the scientists want to study the different phases of use and the precise architectural appearance of the temple in more depth, in order to learn more about the religion of the Etruscans, the social structures in Vulci and what the lives of the city's inhabitants were really like.

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Death of a star reveals midsize black hole lurking in a dwarf galaxy

An intermediate-mass black hole lurking undetected in a dwarf galaxy revealed itself to astronomers when it gobbled up an unlucky star that strayed too close. The shredding of the star, known as a "tidal disruption event" or TDE, produced a flare of radiation that briefly outshone the combined stellar light of the host dwarf galaxy and could help scientists better understand the relationships between black holes and galaxies.

The flare was captured by astronomers with the Young Supernova Experiment (YSE), a survey designed to detect cosmic explosions and transient astrophysical events. An international team led by scientists at UC Santa Cruz, the Niels Bohr Institute at the University of Copenhagen, and Washington State University reported the discovery in a paper published November 10 in Nature Astronomy.

"This discovery has created widespread excitement because we can use tidal disruption events not only to find more intermediate-mass black holes in quiet dwarf galaxies, but also to measure their masses," said coauthor Ryan Foley, an assistant professor of astronomy and astrophysics at UC Santa Cruz who helped plan the YSE survey.

First author Charlotte Angus at the Niels Bohr Institute said the team's findings provide a baseline for future studies of midsize black holes.

"The fact that we were able to capture this midsize black hole whilst it devoured a star offered us a remarkable opportunity to detect what otherwise would have been hidden from us," Angus said. "What is more, we can use the properties of the flare itself to better understand this elusive group of middle-weight black holes, which could account for the majority of black holes in the centers of galaxies."

Supermassive black holes are found at the centers of all massive galaxies, including our own Milky Way. Astronomers conjecture that these massive beasts, with millions or billions of times the mass of the sun, could have grown from smaller "intermediate-mass" black holes with thousands to hundreds of thousands of solar masses.

One theory for how such massive black holes were assembled is that the early universe was rampant with small dwarf galaxies with intermediate-mass black holes. Over time, these dwarf galaxies would have merged or been gobbled up by more massive galaxies, their cores combining each time to build up the mass in the center of the growing galaxy. This merger process would eventually create the supermassive black holes seen today.

"If we can understand the population of intermediate-mass black holes out there -- how many there are and where they are located -- we can help determine if our theories of supermassive black hole formation are correct," said coauthor Enrico Ramirez-Ruiz, professor of astronomy and astrophysics at UCSC and Niels Bohr Professor at the University of Copenhagen.

But do all dwarf galaxies have midsize black holes?

"That's difficult to assert, because detecting intermediate-mass black holes is extremely challenging," Ramirez-Ruiz said.

Classic black hole hunting techniques, which look for actively feeding black holes, are often not sensitive enough to uncover black holes in the centers of dwarf galaxies. As a result, only a minuscule fraction of dwarf galaxies is known to host intermediate-mass black holes. Finding more midsize black holes with tidal disruption events could help to settle the debate about how supermassive black holes form.

"One of the biggest open questions in astronomy is currently how supermassive black holes form," said coauthor Vivienne Baldassare, professor of physics and astronomy at Washington State University.

Data from the Young Supernova Experiment enabled the team to detect the first signs of light as the black hole began to eat the star. Capturing this initial moment was pivotal to unlocking how big the black hole was, because the duration of these events can be used to measure the mass of the central black hole. This method, which until now had only been shown to work well for supermassive black holes, was first proposed by Ramirez-Ruiz and coauthor Brenna Mockler at UC Santa Cruz.

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Evolution of tree roots may have driven mass extinctions

The evolution of tree roots may have triggered a series of mass extinctions that rocked the Earth's oceans during the Devonian Period over 300 million years ago, according to a study led by scientists at IUPUI, along with colleagues in the United Kingdom.

Evidence for this new view of a remarkably volatile period in Earth's pre-history is reported in the Geological Society of America Bulletin. The study was led by Gabriel Filippelli, Chancellor's Professor of Earth Sciences in the School of Science at IUPUI, and Matthew Smart, a Ph.D. student in his lab at the time of the study.

"Our analysis shows that the evolution of tree roots likely flooded past oceans with excess nutrients, causing massive algae growth," Filippelli said. "These rapid and destructive algae blooms would have depleted most of the oceans' oxygen, triggering catastrophic mass extinction events."

The Devonian Period, which occurred 419 million to 358 million years ago, prior to the evolution of life on land, is known for mass extinction events, during which it's estimated nearly 70 percent of all life on Earth perished.

The process outlined in the study -- known scientifically as eutrophication -- is remarkably similar to modern, albeit smaller-scale, phenomenon currently fueling broad "dead zones" in the Great Lakes and the Gulf of Mexico, as excess nutrients from fertilizers and other agricultural runoff trigger massive algae blooms that consume all of the water's oxygen.

The difference is that these past events were likely fueled by tree roots, which pulled nutrients from the land during times of growth, then abruptly dumped them into the Earth's water during times of decay.

The theory is based upon a combination of new and existing evidence, Filippelli said.

Based upon a chemical analysis of stone deposits from ancient lake beds -- whose remnants persist across the globe, including the samples used in the study from sites in Greenland and off the northeast coast of Scotland -- the researchers were able to confirm previously identified cycles of higher and lower levels of phosphorus, a chemical element found in all life on Earth.

They were also able to identify wet and dry cycles based upon signs of "weathering" -- or soil formation -- caused by root growth, with greater weathering indicating wet cycles with more roots and less weathering indicating dry cycles with fewer roots.

Most significantly, the team found the dry cycles coincided with higher levels of phosphorus, suggesting dying roots released their nutrients into the planet's water during these times.

"It's not easy to peer over 370 million years into the past," said Smart. "But rocks have long memories, and there are still places on Earth where you can use chemistry as a microscope to unlock the mysteries of the ancient world."

In light of the phosphorus cycles occurring at the same time as the evolution of the first tree roots -- a feature of Archaeopteris, also the first plant to grow leaves and reach heights of 30 feet -- the researchers were able to pinpoint the decay of tree roots as the prime suspect behind the Devonian Periods extinction events.

Fortunately, Filippelli said, modern trees don't wreak similar destruction since nature has since evolved systems to balance out the impact of rotting wood. The depth of modern soil also retains more nutrients compared to the thin layer of dirt that covered the ancient Earth.

But the dynamics revealed in the study shed light on other newer threats to life in Earth's oceans. The study's authors note that others have made the argument that pollution from fertilizers, manure and other organic wastes, such as sewage, have placed the Earth's oceans on the "edge of anoxia," or a complete lack of oxygen.

"These new insights into the catastrophic results of natural events in the ancient world may serve as a warning about the consequences of similar conditions arising from human activity today," Fillipelli said.

Read more at Science Daily

The world will probably warm beyond the 1. 5-degree limit, but peak warming can be curbed

The world's current climate pledges are insufficient to keep the goal of the 2015 Paris Agreement firmly within grasp. Global warming will likely surpass the 1.5-degree Celsius limit. We are going to overshoot.

But countries can curb time spent in a warmer world by adopting more ambitious climate pledges and decarbonizing faster, according to new research led by scientists at the Department of Energy's Pacific Northwest National Laboratory, the University of Maryland and the U.S. Environmental Protection Agency. Doing so, they warn, is the only way to minimize the overshoot.

While exceeding the 1.5-degree limit appears inevitable, the researchers chart several potential courses in which the overshoot period is shortened, in some cases by decades. The study published today in the journal Nature Climate Change, during the 2022 United Nations Climate Change Conference, also known as COP27, held in Sharm El Sheikh, Egypt.

"Let's face it. We are going to breach the 1.5 degrees limit in the next couple of decades," said corresponding author and PNNL scientist Haewon McJeon. "That means we'll go up to 1.6 or 1.7 degrees or above, and we'll need to bring it back down to 1.5. But how fast we can bring it down is key."

Every second shaved off the overshoot translates to less time courting the most harmful consequences of global warming, from extreme weather to rising sea levels. Forgoing or delaying more ambitious goals could lead to "irreversible and adverse consequences for human and natural systems," said lead author Gokul Iyer, a scientist alongside McJeon at the Joint Global Change Research Institute, a partnership between PNNL and the University of Maryland.

"Moving fast means hitting net-zero pledges sooner, decarbonizing faster, and striking more ambitious emissions targets," said Iyer. "Every little bit helps, and you need a combination of all of it. But our results show that the most important thing is doing it early. Doing it now, really."

During COP26 in 2021, the same research team found that the then updated pledges could substantially increase the chance of limiting warming to 2 degrees Celsius over pre-industrial levels. In their new paper, the authors take an additional step in answering the question of how to move the needle from 2 to 1.5 degrees.

"The 2021 pledges don't add up to anywhere near 1.5 degrees -- we are forced to focus on the overshoot," said PNNL scientist Yang Ou, who co-led the study. "Here, we're trying to provide scientific support to help answer the question: What type of ratcheting mechanism would get us back down and below 1.5 degrees? That's the motivation behind this paper."

The Paths Forward

The authors model scenarios -- 27 emissions pathways in total, each ranging in ambition -- to explore what degree of warming would likely follow which course of action. At a base level, the authors assume that countries will meet their emissions pledges and long-term strategies on schedule.

In more ambitious scenarios, the authors model how much warming is limited when countries decarbonize faster and advance the dates of their net-zero pledges. Their results underscore the significance of "ratcheting near-term ambition," which entails rapid reductions in carbon dioxide emissions from all sectors of the energy system, immediately and through 2030.

If countries uphold their nationally determined contributions through 2030 and follow a two percent minimum decarbonization rate, for example, global carbon dioxide levels would not reach net zero this century.

Taking the most ambitious path outlined, however, could bring net-zero carbon dioxide emissions by 2057. Such a path, the authors write, is marked by "rapid transformations throughout the global energy system" and the scaling up of "low-carbon technologies like renewables, nuclear energy, as well as carbon capture and storage."

"The technologies that help us get to zero emissions include renewables, hydrogen, electric cars, and so on. Of course those are important players," said Iyer. "Another important piece of the puzzle is the technologies that can remove carbon dioxide from the atmosphere, like direct air capture or nature-based solutions."

The most ambitious scenarios outlined in their work are meant to be illustrative of the pathways on offer. But the central takeaway remains clear throughout all modeled scenarios: if 1.5 degrees is to be reattained sooner after we warm past it, more ambitious climate pledges must come.

Read more at Science Daily

New technology creates carbon neutral chemicals out of thin air

It is possible to capture carbon dioxide (CO2) from the surrounding atmosphere and repurpose it into useful chemicals usually made from fossil fuels, according to a study from the University of Surrey.

The technology could allow scientists to both capture CO2 and transform it into useful chemicals such as carbon monoxide and synthetic natural gas in one circular process.

Dr Melis Duyar, Senior Lecturer of Chemical Engineering at the University of Surrey commented:

"Capturing CO2 from the surrounding air and directly converting it into useful products is exactly what we need to approach carbon neutrality in the chemicals sector. This could very well be a milestone in the steps needed for the UK to reach its 2050 net-zero goals.

"We need to get away from our current thinking on how we produce chemicals, as current practices rely on fossil fuels which are not sustainable. With this technology we can supply chemicals with a much lower carbon footprint and look at replacing fossil fuels with carbon dioxide and renewable hydrogen as the building blocks of other important chemicals."

The technology uses patent-pending switchable Dual Function Materials (DFMs), that capture carbon dioxide on their surface and catalyse the conversion of captured CO2 directly into chemicals. The "switchable" nature of the DFMs comes from their ability to produce multiple chemicals depending on the operating conditions or the composition of the added reactant. This makes the technology responsive to variations in demand for chemicals as well as availability of renewable hydrogen as a reactant.

Dr Duyar continued:

"These outcomes are a testament to the research excellence at Surrey, with continuously improving facilities, internal funding schemes and a collaborative culture."

Loukia-Pantzechroula Merkouri, Postgraduate student leading this research at the University of Surrey added:

"Not only does this research demonstrate a viable solution to the production of carbon neutral fuels and chemicals, but it also offers an innovative approach to combat the ever-increasing CO2 emissions contributing to global warming."

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Beer hops compounds could help protect against Alzheimer's disease

Beer is one of the oldest and most popular beverages in the world, with some people loving and others hating the distinct, bitter taste of the hops used to flavor its many varieties. But an especially "hoppy" brew might have unique health benefits. Recent research published in ACS Chemical Neuroscience reports that chemicals extracted from hop flowers can, in lab dishes, inhibit the clumping of amyloid beta proteins, which is associated with Alzheimer's disease (AD).

AD is a debilitating neurodegenerative disease, often marked by memory loss and personality changes in older adults. Part of the difficulty in treating the disease is the time lag between the start of underlying biochemical processes and the onset of symptoms, with several years separating them. This means that irreversible damage to the nervous system occurs before one even realizes they may have the disease. Accordingly, preventative strategies and therapeutics that can intervene before symptoms appear are of increasing interest.

One of these strategies involves "nutraceuticals," or foods that have some type of medicinal or nutritional function. The hop flowers used to flavor beers have been explored as one of these potential nutraceuticals, with previous studies suggesting that the plant could interfere with the accumulation of amyloid beta proteins associated with AD. So, Cristina Airoldi, Alessandro Palmioli and colleagues wanted to investigate which chemical compounds in hops had this effect.

To identify these compounds, the researchers created and characterized extracts of four common varieties of hops using a method similar to that used in the brewing process. In tests, they found that the extracts had antioxidant properties and could prevent amyloid beta proteins from clumping in human nerve cells. The most successful extract was from the Tettnang hop, found in many types of lagers and lighter ales. When that extract was separated into fractions, the one containing a high level of polyphenols showed the most potent antibiotic and aggregation-inhibiting activity. It also promoted processes that allow the body to clear out misfolded, neurotoxic proteins. Finally, the team tested the Tettnang extract in a C. elegans model and found that it protected the worms from AD-related paralysis, though the effect was not very pronounced. The researchers say that although this work may not justify drinking more bitter brews, it shows that hop compounds could serve as the basis for nutraceuticals that combat the development of AD.

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Water is critical for success on climate action

New research shows that water is much more important in mitigating climate change than previously believed. Better management of water is critical to tackling today's food and energy crises, both of which are exacerbated by climate change.

The report titled "The essential drop to reach Net-Zero: Unpacking Freshwater's Role in Climate Change Mitigation," released today, is the first-ever summary of current research on the role of water in climate mitigation. A key message is the need to better understand global water shortages and scarcity in order to plan climate targets that do not backfire in future. If not planned carefully, negative impacts of climate action on freshwater resources might threaten water security and even increase future adaptation and mitigation burdens.

"Most of the measures needed to reach net-zero carbon targets can have a big impact on already dwindling freshwater resources around the world," said Dr Lan Wang Erlandsson from Stockholm Resilience Centre at Stockholm University. "With better planning, such risks can be reduced or avoided."

The report describes why, where, and how freshwater should be integrated into climate change mitigation plans to avoid unexpected consequences and costly policy mistakes. Even efforts usually associated with positive climate action -- such as forest restoration or bioenergy -- can have negative impacts if water supplies are not considered.

Done right, however, water-related and nature-based solutions can instead address both the climate crisis and other challenges, said Dr Malin Lundberg Ingemarsson from Stockholm International Water Institute (SIWI).

"We have identified water risks, but also win-win solutions that are currently not used to their full potential. One example is restoration of forests and wetlands which bring social, ecological, and climate benefits all at once. Another example is that better wastewater treatment can reduce greenhouse gas emissions from untreated wastewater, while improving surface water and groundwater quality, and even provide renewable energy through biogas."

The report highlights five key messages on the interlinkage between water and mitigation:

• Climate mitigation measures depend on freshwater resources. Climate mitigation planning and action need to account for current and future freshwater availability.

• Freshwater impacts -- both positive and negative -- need to be evaluated and included in climate mitigation planning and action.

• Water and sanitation management can reduce greenhouse gas emissions. More efficient drinking water and sanitation services save precious freshwater resources and reduce emissions.

• Nature-based solutions to mitigate climate change can deliver multiple benefits for people and the environment. Measures safeguarding freshwater resources, protecting biodiversity, and ensuring resilient livelihoods are crucial.

• Joint water and climate governance need to be coordinated and strengthened. Mainstreaming freshwater in all climate mitigation planning and action requires polycentric and inclusive governance.

"Climate change mitigation efforts will not succeed if failing to consider water needs," said Marianne Kjellén, United Nations Development Programme (UNDP). "Water must be part of powerful solutions for enhancing ecosystem resilience, preserving biodiversity and regenerative food and energy production systems. In short, water security needs to be factored in to climate action," she adds.

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Rare 'fossil' clam discovered alive

Discovering a new species is always exciting, but so is finding one alive that everyone assumed had been lost to the passage of time. A small clam, previously known only from fossils, has recently been found living at Naples Point, just up the coast from UC Santa Barbara. The discovery appears in the journal Zookeys.

"It's not all that common to find alive a species first known from the fossil record, especially in a region as well-studied as Southern California," said co-author Jeff Goddard, a research associate at UC Santa Barbara's Marine Science Institute. "Ours doesn't go back anywhere near as far as the famous Coelacanth or the deep-water mollusk Neopilina galatheae -- representing an entire class of animals thought to have disappeared 400 million years ago -- but it does go back to the time of all those wondrous animals captured by the La Brea Tar Pits."

On an afternoon low tide in November 2018, Goddard was turning over rocks searching for nudibranch sea slugs at Naples Point, when a pair of small, translucent bivalves caught his eye. "Their shells were only 10 millimeters long," he said. "But when they extended and started waving about a bright white-striped foot longer than their shell, I realized I had never seen this species before." This surprised Goddard, who has spent decades in California's intertidal habitats, including many years specifically at Naples Point. He immediately stopped what he was doing to take close-up photos of the intriguing animals.

With quality images in hand, Goddard decided not to collect the animals, which appeared to be rare. After pinning down their taxonomic family, he sent the images to Paul Valentich-Scott, curator emeritus of malacology at the Santa Barbara Museum of Natural History. "I was surprised and intrigued," Valentich-Scott recalled. "I know this family of bivalves (Galeommatidae) very well along the coast of the Americas. This was something I'd never seen before."

He mentioned a few possibilities to Goddard, but said he'd need to see the animal in-person to make a proper assessment. So, Goddard returned to Naples Point to claim his clam. But after two hours combing just a few square meters, he still hadn't caught sight of his prize. The species would continue to elude him many more times.

Nine trips later, in March 2019, and nearly ready to give up for good, Goddard turned over yet another rock and saw the needle in the haystack: A single specimen, next to a couple of small white nudibranchs and a large chiton. Valentich-Scott would get his specimen at last, and the pair could finally set to work on identification.

Valentich-Scott was even more surprised once he got his hands on the shell. He knew it belonged to a genus with one member in the Santa Barbara region, but this shell didn't match any of them. It raised the exciting possibility that they had found a new species.

"This really started 'the hunt' for me," Valentich-Scott said. "When I suspect something is a new species, I need to track back through all of the scientific literature from 1758 to the present. It can be a daunting task, but with experience it can go pretty quickly."

The two researchers decided to check out an intriguing reference to a fossil species. They tracked down illustrations of the bivalve Bornia cooki from the paper describing the species in 1937. It appeared to match the modern specimen. If confirmed, this would mean that Goddard had found not a new species, but a sort of living fossil.

It is worth noting that the scientist who described the species, George Willett, estimated he had excavated and examined perhaps 1 million fossil specimens from the same location, the Baldwin Hills in Los Angeles. That said, he never found B. cooki himself. Rather, he named it after Edna Cook, a Baldwin Hills collector who had found the only two specimens known.

Valentich-Scott requested Willett's original specimen (now classified as Cymatioa cooki) from the Natural History Museum of Los Angeles County. This object, called the "type specimen," serves to define the species, so it's the ultimate arbiter of the clam's identification.

Meanwhile, Goddard found another specimen at Naples Point -- a single empty shell in the sand underneath a boulder. After carefully comparing the specimens from Naples Point with Willett's fossil, Valentich-Scott concluded they were the same species. "It was pretty remarkable," he recalled.

Small size and cryptic habitat notwithstanding, all of this begs the question of how the clam eluded detection for so long. "There is such a long history of shell-collecting and malacology in Southern California -- including folks interested in the harder to find micro-mollusks -- that it's hard to believe no one found even the shells of our little cutie," Goddard said.

He suspects the clams may have arrived here on currents as planktonic larvae, carried up from the south during marine heatwaves from 2014 through 2016. These enabled many marine species to extend their distributions northward, including several documented specifically at Naples Point. Depending on the animal's growth rate and longevity, this could explain why no one had noticed C. cooki at the site prior to 2018, including Goddard, who has worked on nudibranchs at Naples Point since 2002.

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Differences between brains of primates are small but significant, study shows

While the physical differences between humans and non-human primates are quite distinct, a new study reveals their brains may be remarkably similar. And yet, the smallest changes may make big differences in developmental and psychiatric disorders.

Understanding the molecular differences that make the human brain distinct can help researchers study disruptions in its development. A new study, published recently in the journal Science by a team including University of Wisconsin-Madison neuroscience professor Andre Sousa, investigates the differences and similarities of cells in the prefrontal cortex -- the frontmost region of the brain, an area that plays a central role in higher cognitive functions -- between humans and non-human primates such as chimpanzees, Rhesus macaques and marmosets.

The cellular differences between these species may illuminate steps in their evolution and how those differences can be implicated in disorders, such as autism and intellectual disabilities, seen in humans. Sousa, who studies the developmental biology of the brain at UW-Madison's Waisman Center, decided to start by studying and categorizing the cells in the prefrontal cortex in partnership with the Yale University lab where he worked as a postdoctoral researcher.

"We are profiling the dorsolateral prefrontal cortex because it is particularly interesting. This cortical area only exists in primates. It doesn't exist in other species," Sousa says. "It has been associated with several relevant functions in terms of high cognition, like working memory. It has also been implicated in several neuropsychiatric disorders. So, we decided to do this study to understand what is unique about humans in this brain region."

Sousa and his lab collected genetic information from more than 600,000 prefrontal cortex cells from tissue samples from humans, chimpanzees, macaques and marmosets. They analyzed that data to categorize the cells into types and determine the differences in similar cells across species. Unsurprisingly, the vast majority of the cells were fairly comparable.

"Most of the cells are actually very similar because these species are relatively close evolutionarily," Sousa says.

Sousa and his collaborators found five cell types in the prefrontal cortex that were not present in all four of the species. They also found differences in the abundancies of certain cell types as well as diversity among similar cell populations across species. When comparing a chimpanzee to a human the differences seem huge -- from their physical appearances down to the capabilities of their brains. But at the cellular and genetic level, at least in the prefrontal cortex, the similarities are many and the dissimilarities sparing.

"Our lab really wants to know what is unique about the human brain. Obviously from this study and our previous work, most of it is actually the same, at least among primates," Sousa says.

The slight differences the researchers found may be the beginning of determining some of those unique factors, and that information could lead to revelations about development and developmental disorders at a molecular level.

"We want to know what happened after the evolutionary split between humans and other primates," Sousa says. "The idea is you have a mutation in a gene or in several genes and those genes now have slightly different functions. But if these genes are relevant for brain development, for example, how many of a certain cell is produced, or how cells are connecting to other cells, how is it affecting the neuronal circuitry and their physiological properties? We want to understand how these differences lead to differences in the brain and then lead to differences we can observe in adults."

The study's observations were made in the brains of adults, after much of the development is complete. This means that the differences may be occurring during the brain's development. So, the researchers' next step is to study samples from developing brains and extend their area of investigation past the prefrontal cortex to potentially find where and when these differences originate. The hope is that this information will lead to a more robust foundation to lay developmental disorder research on top of.

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Early planetary migration can explain missing planets

A new model that accounts for the interplay of forces acting on newborn planets can explain two puzzling observations that have cropped up repeatedly among the more than 3,800 planetary systems cataloged to date.

One puzzle known as the "radius valley" refers to the rarity of exoplanets with a radius about 1.8 times that of Earth. NASA's Kepler spacecraft observed planets of this size about 2-3 times less frequently than it observed super-Earths with radii about 1.4 times that of Earth and mini-Neptunes with radii about 2.5 times Earth's. The second mystery, known as "peas in a pod," refers to neighboring planets of similar size that have been found in hundreds of planetary systems. Those include TRAPPIST-1 and Kepler-223, which also feature planetary orbits of near-musical harmony.

"I believe we are the first to explain the radius valley using a model of planet formation and dynamical evolution that self-consistently accounts for multiple constraints of observations," said Rice University's André Izidoro, corresponding author of a study published this week in Astrophysical Journal Letters. "We're also able to show that a planet-formation model incorporating giant impacts is consistent with the peas-in-a-pod feature of exoplanets."

Izidoro, a Welch Postdoctoral Fellow at Rice's NASA-fundedCLEVER Planets project, and co-authors used a supercomputer to simulate the first 50 million years of the development of planetary systems using a planetary migration model. In the model, protoplanetary disks of gas and dust that give rise to young planets also interact with them, pulling them closer to their parent stars and locking them in resonant orbital chains. The chains are broken within a few million years, when the disappearance of the protoplanetary disk causes orbital instabilities that lead two or more planets to slam into one another.

Planetary migration models have been used to study planetary systems that have retained their resonant orbital chains. For example, Izidoro and CLEVER Planets colleagues used a migration model in 2021 to calculate the maximum amount of disruption TRAPPIST-1's seven-planet system could have withstood during bombardment and still retained its harmonious orbital structure.

In the new study, Izidoro partnered with CLEVER Planets' investigators Rajdeep Dasgupta and Andrea Isella, both of Rice, Hilke Schlichting of the University of California, Los Angeles, and Christian Zimmermann and Bertram Bitsch of the Max Planck Institute for Astronomy in Heidelberg, Germany.

"The migration of young planets towards their host stars creates overcrowding and frequently results in cataclysmic collisions that strip planets of their hydrogen-rich atmospheres," Izidoro said. "That means giant impacts, like the one that formed our moon, are probably a generic outcome of planet formation."

The research suggests planets come in two "flavors," super-Earths that are dry, rocky and 50% larger than Earth, and mini-Neptunes that are rich in water ice and about 2.5 times larger than Earth. Izidoro said new observations seem to support the results, which conflict with the traditional view that both super-Earths and mini-Neptunes are exclusively dry and rocky worlds.

Based on their findings, the researchers made predictions that can be tested by NASA's James Webb Space Telescope. They suggest, for instance, that a fraction of planets about twice Earth's size will both retain their primordial hydrogen-rich atmosphere and be rich in water.

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Geobiologists shine new light on Earth's first known mass extinction event 550 million years ago

A new study by Virginia Tech geobiologists traces the cause of the first known mass extinction of animals to decreased global oxygen availability, leading to the loss of a majority of animals present near the end of the Ediacaran Period some 550 million years ago.

The research spearheaded by Scott Evans, a postdoctoral researcher in the Department of Geosciences, part of the Virginia Tech College of Science, shows this earliest mass extinction of about 80 percent of animals across this interval. "This included the loss of many different types of animals, however those whose body plans and behaviors indicate that they relied on significant amounts of oxygen seem to have been hit particularly hard," Evans said. "This suggests that the extinction event was environmentally controlled, as are all other mass extinctions in the geologic record."

Evans' work was published Nov. 7 in the Proceedings of the National Academy of Sciences, a peer-reviewed journal of the National Academy of Sciences. The study was co-authored by Shuhai Xiao, also a professor in the Department of Geosciences, and several researchers led by Mary Droser from the University of California Riverside's Department of Earth and Planetary Sciences, where Evans earned his master's degree and Ph.D.

"Environmental changes, such as global warming and deoxygenation events, can lead to massive extinction of animals and profound disruption and reorganization of the ecosystem," said Xiao, who is an affiliated member of the Global Change Center, part of the Virginia Tech Fralin Life Sciences Institute. "This has been demonstrated repeatedly in the study of Earth history, including this work on the first extinction documented in the fossil record. This study thus informs us about the long-term impact of current environmental changes on the biosphere."

What exactly caused the drop in global oxygen? That's still up for debate. "The short answer to how this happened is we don't really know," Evans said. "It could be any number and combination of volcanic eruptions, tectonic plate motion, an asteroid impact, etc., but what we see is that the animals that go extinct seem to be responding to decreased global oxygen availability."

The study by Evans and Xiao is timelier than one would think. In an unconnected study, Virginia Tech scientists recently found that anoxia, the loss of oxygen availability, is affecting the world's fresh waters. The cause? The warming of waters brought on by climate change and excess pollutant runoff from land use. Warming waters diminish fresh water's capacity to hold oxygen, while the breakdown of nutrients in runoff by freshwater microbes gobbles up oxygen.

"Our study shows that, as with all other mass extinctions in Earth's past, this new, first mass extinction of animals was caused by major climate change -- another in a long list of cautionary tales demonstrating the dangers of our current climate crisis for animal life," said Evans, who is an Agouron Institute Geobiology fellow.

Some perspective: The Ediacaran Period spanned roughly 96 million years, bookended on either side by the end of Cryogenian Period -- 635 million years ago -- and the beginning of the Cambrian Period -- 539 million years ago. The extinction event comes just before a significant break in the geologic record, from the Proterozoic Eon to the Phanerozoic Eon.

There are five known mass extinctions that stand out in the history of animals, the "Big Five," according to Xiao, including the Ordovician-Silurian Extinction (440 million years ago), the late Devonian Extinction (370 million years ago), the Permian-Triassic Extinction (250 million years ago), the Triassic-Jurassic Extinction (200 million years ago), and the Cretaceous-Paleogene Extinction (65 million years ago).

"Mass extinctions are well recognized as significant steps in the evolutionary trajectory of life on this planet," Evans and team wrote in the study. Whatever the instigating cause of the mass extinction, the result was multiple major shifts in environmental conditions. "Particularly, we find support for decreased global oxygen availability as the mechanism responsible for this extinction. This suggests that abiotic controls have had significant impacts on diversity patterns throughout the more than 570 million-year history of animals on this planet," the authors wrote.

Fossil imprints in rock tell researchers how the creatures that perished in this extinction event would have looked. And they looked, in Evans' words, "weird."

"These organisms occur so early in the evolutionary history of animals that in many cases they appear to be experimenting with different ways to build large, sometimes mobile, multicellular bodies," Evans said. "There are lots of ways to recreate how they look, but the take-home is that before this extinction the fossils we find don't often fit nicely into the ways we classify animals today. Essentially, this extinction may have helped pave the way for the evolution of animals as we know them."

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Ceramics that breathe oxygen at lower temperatures help us breathe cleaner air

Although much of the discourse on reducing vehicle emissions centres on electric vehicles (EV), their sales remain low -- with EV vehicles accounting for a mere 1% of car purchases in Japan in 2021. Meanwhile, the European Union is expected to pass stricter emission standards in the near future. This makes improving the performance and functionality of exhaust gas purification catalysts in petrol or diesel-powered vehicles a critical component in the push towards carbon neutrality.

Nearly all petrol or diesel cars are equipped with catalytic converters that remove harmful hydrocarbons, carbon monoxide and nitrogen oxide and convert them into safer gases such as nitrogen, carbon dioxide and water vapor. The toxic gases flow through a honeycomb structure, coated with exhaust gas purifying catalysts.

Ceramics with an oxygen storage capacity (OSC) play a crucial role in the purification process. They help remove noxious gases and prevent the precious metals in catalytic converters from coarsening, which degrades their purification capabilities.

To improve their potential, however, a lower operating temperature is required. But scientists have struggled to achieve this since reducing the temperature to less than 500 ºC results in slower ion diffusion.

Now, a research group at Tohoku University's Graduate School of Engineering has developed a Cerium-Zirconium-based (Ce-Zr) oxide with excellent OSC at 400 ºC by controlling its crystal structure. The OSC at 400 ºC was higher than conventional materials by a factor of 13.5, even without precious metal catalysts.

"The key to our success was introducing a tiny amount of transition metals, such as iron, to the Ce-Zr-based oxides," said Professor Hitoshi Takamura, leader of the research group.

The 'transition metal doping' had two notable effects in the oxides. It accelerated the oxygen diffusion by easing the formation of oxygen vacancies and promoted cation ordering.

"Cation ordering tidies up the crystal structure and makes oxygen readily released," explained Takamura.

The iron doping reduced the cation-ordering temperature, which in turn enabled a larger surface area for the Ce-Zr-based oxides. This enhanced their durability and ability to purify toxic gases.

In the future, Takamura and his group hope to test the material by loading it with palladium on honeycomb supports.

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Want to fire up the dance floor? Play low-frequency bass

To find out how different aspects of music influence the body, researchers turned a live electronic music concert into a lab study. By introducing levels of bass over speakers that were too low to hear and monitoring the crowd's movements, scientists found that people danced 11.8 percent more when the very low frequency bass was present. The study appears November 7 in the journal Current Biology.

"I'm trained as a drummer, and most of my research career has been focused on the rhythmic aspects of music and how they make us move," says first author Daniel Cameron, a neuroscientist from McMaster University. "Music is a biological curiosity -- it doesn't reproduce us, it doesn't feed us, and it doesn't shelter us, so why do humans like it and why do they like to move to it?"

Cameron conducts research at the McMaster LIVELab, which connects science with live performance in a unique research theater. It is equipped with 3D motion capture, a Meyer sound system that can replicate various concert environments, and enhanced speakers that can produce extremely low frequencies, so low they were undetectable to the human ear.

For the Current Biology study, Cameron and colleagues recruited participants attending a LIVELab concert for electronic musical duo Orphx. The concertgoers were equipped with motion-sensing headbands to monitor their dance moves. Additionally, they were asked to fill out survey forms before and after the event. These forms were used to ensure the sound was undetectable, measure concert enjoyment, and examine how the music felt physically.

Throughout the 45-minute concert, the researchers manipulated the very-low bass-playing speakers, turning them on and off every two minutes. They found the amount of movement was 12 percent greater when the speakers were on.

"The musicians were enthusiastic to participate because of their interest in this idea that bass can change how the music is experienced in a way that impacts movement," says Cameron. "The study had high ecological validity, as this was a real musical and dance experience for people at a real live show."

The feeling of vibration through touch and the interactions between the inner ear and the brain have close links to the motor system. The researchers speculate these physical processes are at work in the neurological connection between music and movement. This anatomy can pick up on low frequencies and can affect the perception of "groove," spontaneous movement, and rhythm perception.

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Magnetized dead star likely has solid surface

The study, published in the journal Science and led by researchers at the University of Padova, uses data from a NASA satellite, the Imaging X-ray Polarimetry Explorer (IXPE), which was launched last December. The satellite, a collaboration between NASA and the Italian Space Agency, provides a new way of looking at X-ray light in space by measuring its polarisation -- the direction of the light waves' wiggle.

The team looked at IXPE's observation of magnetar 4U 0142+61, located in the Cassiopeia constellation, about 13,000 light years away from Earth. This was the first time polarised X-ray light from a magnetar had been observed.

Magnetars are neutron stars -- very dense remnant cores of massive stars that have exploded as supernovae at the ends of their lives. Unlike other neutron stars, they have an immense magnetic field -- the most powerful in the universe. They emit bright X-rays and show erratic periods of activity, with the emission of bursts and flares which can release in just one second an amount of energy millions of times greater than our Sun emits in one year. They are believed to be powered by their ultra-powerful magnetic fields, 100 to 1,000 times stronger than standard neutron stars.

The research team found a much lower proportion of polarised light than would be expected if the X-rays passed through an atmosphere. (Polarised light is light where the wiggle is all in the same direction -- that is, the electric fields vibrate only in one way. An atmosphere acts as a filter, selecting only one polarisation state of the light.)

The team also found that, for particles of light at higher energies, the angle of polarisation -- the wiggle -- flipped by exactly 90 degrees compared to light at lower energies, following what theoretical models would predict if the star had a solid crust surrounded by an external magnetosphere filled with electric currents.

Co-lead author Professor Silvia Zane (UCL Mullard Space Science Laboratory), a member of the IXPE science team, said: "This was completely unexpected. I was convinced there would be an atmosphere. The star's gas has reached a tipping point and become solid in a similar way that water might turn to ice. This is a result of the star's incredibly strong magnetic field.

"But, like with water, temperature is also a factor -- a hotter gas will require a stronger magnetic field to become solid.

"A next step is to observe hotter neutron stars with a similar magnetic field, to investigate how the interplay between temperature and magnetic field affects the properties of the star's surface."

Lead author Dr Roberto Taverna, from the University of Padova, said: "The most exciting feature we could observe is the change in polarisation direction with energy, with the polarisation angle swinging by exactly 90 degrees.

"This is in agreement with what theoretical models predict and confirms that magnetars are indeed endowed with ultra-strong magnetic fields."

Quantum theory predicts that light propagating in a strongly magnetised environment is polarised in two directions, parallel and perpendicular to the magnetic field. The amount and direction of the observed polarisation bear the imprint of the magnetic field structure and of the physical state of matter in the vicinity of the neutron star, providing information inaccessible otherwise.

At high energies, photons (particles of light) polarised perpendicularly to the magnetic field are expected to dominate, resulting in the observed 90-degree polarisation swing.

Professor Roberto Turolla, from the University of Padova, who is also an honorary professor at the UCL Mullard Space Science Laboratory, said: "The polarisation at low energies is telling us that the magnetic field is likely so strong to turn the atmosphere around the star into a solid or a liquid, a phenomenon known as magnetic condensation."

The solid crust of the star is thought to be composed of a lattice of ions, held together by the magnetic field. The atoms would not be spherical, but elongated in the direction of the magnetic field.

It is still a subject of debate whether or not magnetars and other neutron stars have atmospheres. However, the new paper is the first observation of a neutron star where a solid crust is a reliable explanation.

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Sugar molecules as a target in cancer therapy

Cancer cells use sugar molecules on their surface to disable attacks by the body's immune system. Researchers at the University of Basel now report on how this mechanism can be neutralized.

The immune system is actually extremely well equipped to get rid of abnormal cells. As a safety mechanism, special features are built into healthy cells so that the immune system recognizes them, thus preventing a mistaken attack. However, cancer cells sneakily manipulate these safety mechanisms in such a way that the immune system leaves them alone.

Over the past few years, immunotherapies have revolutionized cancer treatment. These include therapies that prevent cancer cells from inhibiting the immune response. This involves blocking what are known as "immune checkpoints" using artificially produced proteins, which allows the immune cells to successfully attack the cancer cells.

"With many tumors, however, there have only been modest levels of success. That's why we're looking for new approaches to engage anti-tumor immune responses more efficiently," explains Professor Heinz Läubli from the Department of Biomedicine at the University of Basel and the University Hospital Basel. In the specialist journal Science Translational Medicine, his team, together with that of recent Nobel laureate Professor Carolyn Bertozzi from Stanford University, reports on a promising new approach. By altering sugar molecules on the surface of cancer cells in mice, the researchers were able to produce a significant increase in anti-tumor immune response.

How immune cells turn traitor

Their focus is on sugar molecules on the surface of the cancer cells, as well as on the cells in their immediate vicinity. These particular sugars, which contain sialic acid, also occur on healthy cells, and are important for cell-to-cell communication. However, tumors boost the proportion of these sugars on their surface.

Certain immune cells called macrophages recognize these sialic acid sugars and inadvertently turn traitor: they give other nearby immune cells the impression that all is well. The research team's experiments on mice have now been able to demonstrate that the sialic acid sugars can be removed, or at least very much reduced, with the help of an enzyme. This means that the macrophages no longer prevent the tumor coming under immunological attack.

A target structure for new therapies

More precise analyses have enabled the researchers to identify in mice exactly which receptor it is on the macrophages that recognizes the sialic acid sugars. If the equivalent receptor could be identified in humans, then that could be another interesting target in the bid to tackle cancer cells with the aid of the patient's own immune system.

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Endangered Devils Hole pupfish is one of the most inbred animals known

As its name implies, the Devil's Hole pupfish lives in a truly hellish environment.

Confined to a single deep limestone cave in Nevada's Mojave Desert, 263 of them live in water that hovers around 93 degrees Fahrenheit year-round, with food resources so scarce that they are always on the edge of starvation, and with oxygen levels so low that most other fish would die immediately. The pupfish, Cyprinodon diabolis, live in the smallest habitat of any known vertebrate.

New research now documents the extreme effect that these harsh and isolated conditions have had on this fish's genetic diversity.

In a paper published this week in the journal Proceedings of the Royal Society B, University of California, Berkeley, biologists report the first complete genome sequences of eight pupfish species from the American Southwest -- 30 individuals in all, including eight Devils Hole pupfish. Astoundingly, the Devils Hole pupfish is so inbred that 58% of the genomes of these eight individuals are identical, on average.

"High levels of inbreeding are associated with a higher risk of extinction, and the inbreeding in the Devils Hole pupfish is equal to or more severe than levels reported so far in other isolated natural populations, such as the Isle Royale wolves in Michigan, mountain gorillas in Africa and Indian tigers," said lead researcher Christopher Martin, UC Berkeley associate professor of integrative biology and curator of ichthyology in the campus's Museum of Vertebrate Zoology. "Although we were not able to directly measure fitness, the increased inbreeding in these pupfish likely results in a substantial reduction in fitness."

Other pupfish species are also inbred, the researchers found, but only between 10% and 30% of their genomes are identical.

Graduate student David Tian, lead author of the study, said that the level of inbreeding in the Devils Hole pupfish is equivalent to what would happen if four to five generations of siblings mated with one another. This tends to burn in or fix, rather than weed out, harmful mutations, potentially dooming a population to extinction by mutational meltdown. The Devils Hole pupfish species is currently doing well in the wild and in captive or "refuge" populations, but such low genetic diversity could spell trouble as the climate changes and human impacts become greater.

In the face of these potential threats, the new genome sequences will help scientists and conservationists assess the health of native pupfish populations and potentially intervene in refuge populations to increase the genetic diversity of these species -- the Devils Hole pupfish, in particular.

"With this new genomic data, there's a lot of potential to look not just at genetic diversity and how these species are related to each other phylogenetically, but also look at inbreeding and mutation load to get an idea of what their current status is, how evolutionary history may have influenced their current genetic variation, and think about where the population is going and what we should do, if anything, to preserve these species," Tian said.

Population decline and rescue

Pupfish species are scattered around the globe and tend to like isolated lakes and springs, often with extreme conditions that most fish would find unsurvivable. About 30 species inhabit warm, salty desert springs and streams in California and Nevada. Martin has studied various pupfish populations, including several on San Salvador Island in the Bahamas, to understand the genetics behind their adaptation to extreme conditions and unusual ecological niches.

The Devils Hole pupfish, however, is unique in its small range and perilous existence, Martin said, making its fluctuating population in the wild worrisome to conservationists.

"Part of the question about these declines is whether they may be due to the genetic health of the population," Martin said. "Maybe the declines are because there are harmful mutations that have become fixed because the population is so small."

The small population is partly a result of human incursions into their habitat, Martin noted. Local ranchers and developers pumped groundwater in the region in the 1960s and '70s that drastically reduced the water level in Devils Hole, leading to a drop in population levels. A 1976 Supreme Court ruling that allowed the federal government to limit groundwater pumping saved Devils Hole and the resident population, while captive breeding at a nearby 100,000-gallon pool in the Ash Meadows National Wildlife Refuge rescued the species. Nevertheless, a decline in the 1990s led the wild population to its nadir in 2013: 35 individuals. The wild population has since recovered, while the refuge population has ballooned to about 400, twice the wild population.

Humans are not totally to blame for the lack of genetic diversity in the Devils Hole pupfish, however. The UC Berkeley researchers also sequenced the genome of a pupfish collected in 1980 and held at the University of Michigan. It showed inbreeding and a lack of genetic diversity similar to that found in individuals collected recently, most of which died a natural death. This implies that the pupfish has likely seen population bottlenecks frequently over hundreds, if not thousands, of years.

One result of this, Martin and Tian found, is that 15 genes have disappeared entirely from the Devils Hole pupfish genome. Five of them seem to be involved in adaptation to living in low-oxygen or hypoxic environments.

"These deletions are a paradox, because this is a habitat where you're most exposed to hypoxia," Martin said. "It could have something to do with the stability of the habitat over time. But it looks to us like the hypoxia pathway is broken. Once you break one gene, it doesn't really matter if you break additional genes in that regulatory pathway. Our future work is to actually look at what these deletions do. Do they increase tolerance of hypoxia? Do they decrease tolerance of hypoxia? I think those two scenarios are equally plausible at this time."

Selective breeding within a captive population of Devils Hole pupfish could help increase the diversity and perhaps save the species from eventual extinction, he said. And to restore genes already lost, CRISPR genome editing could add them back.

The fact that the genome of the fish collected in 1980 was about as inbred as today's fish is "maybe good news," Martin said, "in that the population has historically been highly inbred with very low genetic diversity, suggesting that the recent decline in the '90s, with population bottlenecks to only 35 fish in 2013 and 38 fish in 2007, doesn't seem to have had much of an effect."

Tian is currently analyzing about 150 complete genome sequences of nine species of American pupfish to get a more complete picture of the deleterious mutations and gene deletions in the various Southwestern populations. He sees the study as an example of what conservation genomics can do for endangered and possibly inbred populations around the world.

"We're on a really cool cusp when it comes to using genomic data and applying it to conservation, especially at a time where it's a problem that is likely only going to get worse with climate change and increased habitat fragmentation and just anthropogenic changes," he said.

Tian is leery of genetic interventions, however, since little is known about how genes influence the physical and behavioral characteristics of a species and how this relates to fitness and adaptation to a specific environment. Conservation should still be a priority.

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Entomologists issue warning about effects of climate change on insects

In a new scientific review, a team of 70 scientists from 19 countries warned that if no steps are taken to shield insects from the consequences of climate change, it will "drastically reduce our ability to build a sustainable future based on healthy, functional ecosystems."

Citing research from around the world, the team painted a bleak picture of the short- and long-term effects of climate change on insects, many of which have been in a state of decline for decades. Global warming and extreme weather events are already threatening some insects with extinction -- and it will only get worse if current trends continue, scientists say. Some insects will be forced to move to cooler climes to survive, while others will face impacts to their fertility, life cycle and interactions with other species.

Such drastic disruptions to ecosystems could ultimately come back to bite people, explained Anahí Espíndola, an assistant professor of entomology at the University of Maryland and one of the paper's co-authors.

"We need to realize, as humans, that we are one species out of millions of species, and there's no reason for us to assume that we're never going to go extinct," Espíndola said. "These changes to insects can affect our species in pretty drastic ways."

Insects play a central role in ecosystems by recycling nutrients and nourishing other organisms further up the food chain, including humans. In addition, much of the world's food supply depends on pollinators like bees and butterflies, and healthy ecosystems help keep the number of pests and disease-carrying insects in check.

These are just a few of the ecosystem services that could be compromised by climate change, the team of scientists cautioned. Unlike mammals, many insects are ectotherms, which means they are unable to regulate their own body temperature. Because they are so dependent on external conditions, they may respond to climate change more acutely than other animals.

One way that insects cope with climate change is by shifting their range, or permanently relocating to places with lower temperatures. According to one study cited by Espíndola and other scientists, the ranges of nearly half of all insect species will diminish by 50% or more if the planet heats up 3.2°C. If warming is limited to 1.5°C -- the goal of the global Paris Agreement on climate change -- the ranges of 6% of insects will be affected.

Espíndola, who studies the ways in which species respond to environmental changes over time, contributed to the sections of the paper that address range shifts. She explained that drastic changes to a species' range can jeopardize their genetic diversity, potentially hampering their ability to adapt and survive.

On the other hand, climate change may make some insects more pervasive -- to the detriment of human health and agriculture. Global warming is expected to expand the geographical range of some disease vectors (such as mosquitoes) and crop-eating pests.

"Many pests are actually pretty generalist, so that means they are able to feed on many different types of plants," Espíndola said. "And those are the insects that -- based on the data -- seem to be the least negatively affected by climate change."

The team noted that the effects of climate change are often compounded by other human-caused impacts, such as habitat loss, pollution and the introduction of invasive species. Combined, these stressors make it more difficult for insects to adapt to changes in their environment.

Though these effects are already being felt by insects, it is not too late to take action. The paper outlined steps that policymakers and the public can take to protect insects and their habitats. Scientists recommended "transformative action" in six areas: phasing out fossil fuels, curbing air pollutants, restoring and permanently protecting ecosystems, promoting mostly plant-based diets, moving towards a circular economy and stabilizing the global human population.

The paper's lead author, Jeffrey Harvey of the Netherlands Institute of Ecology (NIOO-KNAW) and Vrije Universiteit Amsterdam, said in a statement that urgent action is needed to protect insects and the ecosystems they support.

"Insects are tough little critters, and we should be relieved that there is still room to correct our mistakes," Harvey said. "We really need to enact policies to stabilize the global climate. In the meantime, at both government and individual levels, we can all pitch in and make urban and rural landscapes more insect-friendly."

The paper suggested ways that individuals can help, including managing public, private or urban gardens and other green spaces in a more ecologically-friendly way -- for instance, incorporating native plants into the mix and avoiding pesticides and significant changes in land usage when possible.

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Mars's crust more complex, evolved than previously thought

Early crust on Mars may be more complex than previously thought -- and it may even be similar to our own planet's original crust.

The Martian surface is uniformly basaltic, a product of billions of years of volcanism and flowing lava on the surface that eventually cooled. Because Mars did not undergo full-scale surface remodeling like the shifting of continents on Earth, scientists had thought Mars' crustal history was a relatively simple tale.

But in a new study, researchers found locations in the Red Planet's southern hemisphere with greater concentrations of silicon, a chemical element, than what would be expected in a purely basaltic setting. The silica concentration had been exposed by space rocks that slammed into Mars, excavating material that was embedded miles below the surface, and revealing a hidden past.

"There is more silica in the composition that makes the rocks not basalt, but what we call more evolved in composition," says Valerie Payré, assistant professor in the Department of Earth and Environmental Sciences at the University of Iowa and the study's corresponding author. "That tells us how the crust formed on Mars is definitely more complex than what we knew. So, it's more about understanding that process, and especially what it means for how Earth's crust first formed."

Scientists believe Mars formed about 4.5 billion years ago. Exactly how the Red Planet came into being is a mystery, but there are theories. One idea is that Mars formed via a titanic collision of rocks in space that, with its intense heat, spawned an entirely liquefied state, also known as a magma ocean. The magma ocean gradually cooled, the theory goes, yielding a crust, like a layer of skin, that would be singularly basaltic.

Another theory is that the magma ocean was not all-encompassing, and that parts of the first crust on Mars had a different origin, one that would show silica concentrations different from basaltic.

Payré and her research partners analyzed data gathered by the Mars Reconnaissance Orbiter for the planet's southern hemisphere, which previous research had indicated was the oldest region. The researchers found nine locations -- such as craters and fractures in the terrain -- that were rich in feldspar, a mineral associated with lava flows that are more silicic than basaltic.

"This was the first clue," Payré says. "It is because the terrains are feldspar-rich that we explored the silica concentrations there."

Feldspar had been found previously in other regions on Mars, but further analysis showed the chemical composition in those areas was more basaltic. That did not deter the researchers, who turned to another instrument, called THEMIS, which can detect silica concentrations through infrared wavelength reflections from the Martian surface. With data from THEMIS, the team determined the terrain at their chosen locations was more silicic than basaltic.

Adding further credence to their observations, meteorites such as Erg Chech 002, discovered in the Sahara and dating roughly to the birth of the solar system, show similar silicic and other mineral compositions that the team observed in the nine locations on Mars.

The researchers also dated the crust to about 4.2 billion years, which would make it the oldest crust found on Mars to date.

Payré says she was mildly surprised at the discovery.

"There have been rovers on the surface that have observed rocks that were more silicic than basaltic," she says. "So, there were ideas that the crust could be more silicic. But we never knew, and we still don't know, how the early crust was formed, or how old it is, so it's kind of a mystery still."

While Mars' crustal origin remains shrouded, Earth's crustal history is even less clear, as any vestiges of our planet's original crust have been long erased due to the shifting of continental plates for billions of years. Still, the finding may offer insights into Earth's origins.

"We don't know our planet's crust from the beginning; we don't even know when life first appeared," Payré says. "Many think the two could be related. So, understanding what the crust was like a long time ago could help us understand the whole evolution of our planet."

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Researchers seek to understand why vaccine responses vary from person to person

While vaccines are one of the most powerful public health tools for protecting against infectious disease, not everybody is conferred the same level of protection. Many factors determine whether an individual responding to vaccination will generate an effective response, including specific biomarkers within a person's immune system, but until now there has been no evidence showing whether these factors were universal across a wide range of vaccines.

New findings from a meta-analysis published in Nature Immunology examine the biological mechanisms responsible for why some people's immune systems respond differently to vaccinations, which could have global implications for the development and administration of vaccines.

As part of a series of studies for The Human Immunology Project Consortium (HIPC), a network of national research institutions studying the range of responses to different infections and vaccinations, Emory researchers analyzed the molecular characteristics of 820 healthy young adults who were immunized with 13 different vaccines to identify specific biomarkers that generate antibody response to vaccines.

The participants were separated into three endotypes, or groups with a common gene expression, based on the level of inflammatory response prior to vaccination -- a high inflammatory group, a low inflammatory group, and a mid-inflammatory group. After studying the immunological changes that occurred in participants following vaccination, researchers found the group that had the highest levels of inflammation prior to vaccine had the strongest antibody response.

"We were surprised because inflammation is usually depicted as something that is bad," says Slim Fourati, PhD, bioinformatic research associate at Emory University and first author on the paper. "These data indicate that some types of inflammation can actually foster a stronger response from a vaccine."

Fourati, Dr. Rafick-Pierre Sekaly, professor and senior author of the paper, and the HIPC team identified specific biomarkers among this group and cellular features that characterized the pre-vaccination inflammatory signature, information that can be used to predict how well an individual will respond to a vaccine.

"With the knowledge we now have about what characteristics of the immune system enable a more robust response, vaccines can be tailored to induce this response and maximize their effectiveness," says Fourati. "But we still have more questions to answer."

More research is needed to determine the cause of this inflammation in otherwise healthy adults. Additionally, Fourati suggests future studies should look at how these biomarkers facilitate vaccine protection in older age groups and among populations who are immunocompromised.

Published simultaneously with three other HIPC studies by researchers at Yale's School of Medicine, Stanford University, University of Cincinnati, Harvard Medical School, and Columbia University Medical Center, these findings can serve to improve vaccine response across all individuals. Better understanding of how various pre-vaccine immune states impact antibody responses opens the possibility of altering these states in more vulnerable individuals. For example, scientists may give patients predicted to have a weaker immune response an adjuvant with the vaccine to trigger the inflammatory genes associated with greater protection.

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