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A new paper led by Professor Imanuel Lerman of UC San Diego provides a review of the field of bioelectronic medicine and the most promising opportunities for life-changing new therapies and diagnostics.

A new paper led by Professor Imanuel Lerman of UC San Diego provides a review of the field of bioelectronic medicine and the most promising opportunities for life-changing new therapies and diagnostics.

Scientists are unlocking the secrets of halide perovskites -- a material that's poised to reshape our future by bringing us closer to a new age of energy-efficient optoelectronics. Two physics professors are studying the material at the nanoscale: a place where objects are invisible to the naked eye. At this level, the extraordinary properties of halide perovskites come to life, thanks to the material's unique structure of ultra-thin crystals -- making it astonishingly efficient at converting sunlight into energy. Think solar panels that are not only more affordable but also far more effective at powering homes. Or LED lights that burn brighter and last longer while consuming less energy.

Scientists are unlocking the secrets of halide perovskites -- a material that's poised to reshape our future by bringing us closer to a new age of energy-efficient optoelectronics. Two physics professors are studying the material at the nanoscale: a place where objects are invisible to the naked eye. At this level, the extraordinary properties of halide perovskites come to life, thanks to the material's unique structure of ultra-thin crystals -- making it astonishingly efficient at converting sunlight into energy. Think solar panels that are not only more affordable but also far more effective at powering homes. Or LED lights that burn brighter and last longer while consuming less energy.

A team of researchers has developed innovative methods to enhance frequency conversion of terahertz (THz) waves in graphene-based structures, unlocking new potential for faster, more efficient technologies in wireless communication and signal processing.

A team of researchers has developed innovative methods to enhance frequency conversion of terahertz (THz) waves in graphene-based structures, unlocking new potential for faster, more efficient technologies in wireless communication and signal processing.

Experiments have yielded a fascinating new type of matter, neither granular nor crystalline, that responds to some stresses as a fluid would and to others like a solid. The new material, known as PAM (for polycatenated architected materials) could have uses in areas ranging from helmets and other protective gear to biomedical devices and robotics.

Fast radio bursts are mysterious and brief flashes of radio emissions that were thought to be produced by magnetars, highly magnetized rotating neutron stars. Yet magnetars appear primarily in young star clusters. A repeating burst discovered last year has been pinpointed to the distant outskirts of an old but massive elliptical galaxy where, theoretically, such stars would long since have disappeared. Does this mean magnetars are not the source of FRBs?

NASA’s Curiosity Rover has been exploring Mars since 2012 and, more recently has found evidence of ice-free ancient ponds and lakes on the surface. The rover found small undulations like those seen in sandy lake-beds on Earth. They would have been created by wind-driven water moving back and forth across the surface. The inescapable conclusion is that the water would have been open to the elements instead of being covered by ice. The discovery suggests the ripples formed 3.7 billion years ago. 

Mars it the fourth planet in our Solar System and the second smallest of all the major planets. It’s known for its strong red colour which is caused by iron oxide in the surface material. Classed as a terrestrial planet, Mars is similar in many ways to Earth with valleys, volcanoes and even evidence of dried up river beds. The similarities end there though with polar caps made mostly of carbon dioxide ice, an unbreathable atmosphere and a surface that is cold and dry. It’s always held a special fascination for us due largely to vague hints through the centuries of alien intelligent but more recently that it may have once been habitable. 

A full-disk view of Mars, courtesy of VMC. Credit: ESA

Once such rover that has been exploring the Martian landscape is the Curiosity Rover that was sent by NASA in 2011. It arrived at Mars in August 2012 and has been exploring the region around Gale Crater ever since. The main objective of Curiosity is to investigate the climate and geology and to assess if it could support primative life in the past. To achieve that end, it’s equipped with an array of instruments from drills to collect soil samples, cameras and instruments to analyse atmospheric samples. 

New simulations are helping inform the Curiosity rover’s ongoing sampling campaign. Credit:NASA/JPL-Caltech/MSSS

A paper recently published in the journal Science Advances by Caltech’s John Grotzinger, Harold Brown Professor of Geology and Michael Lamb, Professor of Geology shared their findings. They found two sets of what seem to be ancient wave ripples on the surface of Mars now thought to be dried up bodes of water with the ripples preserved in rock. The ripples are tiny undulations and are often seen in beaches and lake-beds on Earth as wind-driven water flows across the shallows. The team are particularly excited that this means the water was not frozen and was once open to the elements as liquid. 

The ripples discovered by Curiosity in Gale Crater are the strongest evidence to date that there have been bodies of liquid water in the history of the red planet. Analysis of the rocks and ripples suggest they formed 3.7 billion years ago. It’s thought that the atmosphere and climate of Mars must have been far warmer than it is today and more dense. Dense enough to support liquid water in open air.

NASA’s Curiosity rover continues to search for signs that Mars’ Gale Crater conditions could support microbial life. Photo credit: NASA/JPL-Caltech/MSSS.

The team were able to create computer models from the ripples they found to attempt to discover the size of lake. The size of the ripples and separation helps to determine how much water was present. The ripple height of 6mm and 4 to 5 cm separation tells us that the lake was shallow, possibly even less than 2 metres deep. One of the sets of ripples known as the Prow outcrop was found in an area that was once wind blown dunes. The other set was found nearby in the sulcate-rich Amapari Marker Band of rocks. The two regions come from slightly different times telling us that the warm dense atmosphere occurred at multiple times or at least for a long period of time. 

The discovery has been a massive help to Mars paleoclimate studies that have tried to map the changing conditions on Mars. NASA’s Opportunity rover was the first mission to discover ripples on the surface but the nature of the bodies of water was uncertain. This latest discovery has given a fascinating insight into the early conditions on Mars, with perhaps, bodies of liquid dotted across the landscape. Further investigation is needed to see how commonplace the ripples are. 

Source : Signatures of Ice-Free Ancient Ponds and Lakes Found on Mars

The post Curiosity Finds Ancient Wave Ripples on Mars appeared first on Universe Today.

The US contributes around a fifth of the budget for the World Health Organization – its withdrawal from the public health body will impede efforts to control the global spread of diseases and could put the US at risk

Gas is the stuff of star formation, and most galaxies have enough gas in their budget to form some stars. However, the picture is a little different for dwarf galaxies. They lack the mass required to hold onto their gas when more massive neighbouring galaxies are siphoning it off.

New research shows that even isolated dwarf galaxies with no overbearing galactic neighbours struggle to form stars. What’s going on?

The research is centred on ultra-faint dwarf (UFD) galaxies. These tiny galaxies are the faintest galaxies in the Universe and contain only a few hundred stars, up to about one thousand. UFDs also contain ample amounts of dark matter. They’re different from globular clusters because globulars contain tens of thousands up to millions of stars and have very little dark matter, maybe none at all.

Because they’re so faint, astronomers struggle to locate them. The ones that have been found are close to the Milky Way. However, that makes them difficult to study because their massive neighbour dominates them. The Milky Way’s gravity and hot corona can siphon the UFDs’ gas away, making it challenging to understand their natural evolution.

Astronomers working with the DECam and the Gemini South Telescope have successfully located three UFDs well beyond the Milky Way’s gravitational influence. Although they weren’t easy to find, astronomers have made significant discoveries about UFDs from them.

The results are in new research published in The Astrophysical Journal Letters. It’s titled “Three Quenched, Faint Dwarf Galaxies in the Direction of NGC 300: New Probes of Reionization and Internal Feedback.” The lead author is David Sand, an astronomer from the Steward Observatory at the University of Arizona.

Sand found the three UFDs during a painstaking manual search. The UFDs are so faint that algorithmic searches couldn’t detect them.

“It was during the pandemic,” recalled Sand. “I was watching TV and scrolling through the DESI Legacy Survey viewer, focusing on areas of sky that I knew hadn’t been searched before. It took a few hours of casual searching, and then boom! They just popped out.”

The three UFDs are in the direction of the spiral galaxy NGC 300 and the Sculptor constellation. They’re called Sculptor A, Sculptor B, and Sculptor C.

Sculptor A is about 1.35 Mpc away and is likely at the edge of the Local Group, similar to Tucana B. It’s not a direct satellite of NGC 300.

Sculptor B is about 2.48 Mpc away and is likely behind NGC 300.

Sculptor C is about 2.04 Mpc away and is a satellite of NGC 300.

All three UFDs share some characteristics. They contain mostly old, metal-poor stars, are quenched and do not form any new stars, contain no neutral atomic hydrogen (H i), and emit no UV. “None of the three dwarfs are detected in H i line emission in the H i Parkes All Sky Survey, suggesting that they are not gas rich,” Sand and his co-researchers explain in their paper.

The lack of H I and UV both indicate that the galaxies are quenched and star formation has ceased. “Any younger blue stellar population either has few stars associated with it or is below our detection limit,” the authors write.

The discovery of the Sculptor galaxies, as they’re called, supports theories that say UFDs are dead galaxies that ceased star formation a long time ago in the early Universe. So, finding these faint quenched galaxies is entirely expected.

The jarring thing about their discovery is that they’re isolated. They’re not in proximity to any other larger galaxies that could’ve stripped away their gas and quenched their star formation. “The three dwarf galaxies in this work are among the faintest quenched dwarfs discovered outside the Local Group,” the authors write.

“Many of the recently discovered faint dwarf galaxies beyond the Local Group show distinct signs of recent star formation, although a growing subset also appears to be quenched, with little to no recent star formation,” the authors explain. “The mix of stellar populations of faint dwarf galaxies in the “field” is a critical ingredient for understanding the role of reionization, stellar feedback, and ram pressure from the cosmic web in driving the evolution of the smallest galaxies.”

Finding these three UFDs is significant because of their isolation. Only one of them, Sculptor C, is clearly associated with the nearby NGC 300. Sculptors A and B are isolated. Studying them is an opportunity to learn more about how star formation is affected by internal feedback mechanisms in low-mass galaxies. It’s also an opportunity to learn more about ram-pressure stripping, which is when gas is removed from a galaxy through interactions with the surrounding medium and even cosmic reionization.

During cosmic reionization, also known as the Epoch of Reionization, light from the first stars and galaxies reionized the neutral hydrogen in the intergalactic medium. The high-energy UV photons from the stars and galaxies could’ve effectively boiled away the gas in dwarf galaxies, ending their star formation.

An alternative explanation for UFDs losing their gas is supernova explosions. If some of the first stars in UFDs exploded, they could have expelled the gas and ended star formation. Ram-pressure stripping could also have been responsible.

Astronomers still need to learn more about reionization and if it’s responsible, and the Sculptor galaxies can help them.

“We don’t know how strong or uniform this reionization effect is,” explained Sand. “It could be that reionization is patchy, not occurring everywhere all at once. We’ve found three of these galaxies, but that isn’t enough. It would be nice if we had hundreds of them. If we knew what fraction was affected by reionization, that would tell us something about the early Universe that is very difficult to probe otherwise.”

“The Epoch of Reionization potentially connects the current day structure of all galaxies with the earliest formation of structure on a cosmological scale,” said Martin Still, NSF program director for the International Gemini Observatory. “The DESI Legacy Surveys and detailed follow-up observations by Gemini allow scientists to perform forensic archeology to understand the nature of the Universe and how it evolved to its current state.”

Ultimately, astronomers need to find more of these isolated UFDs to constrain their findings.

“Many more faint and ultrafaint dwarf galaxies are predicted at the edges of the Local Group and in nearby, low-density environments, but initial efforts to find them have not always been successful,” the authors write in their conclusion. That only emphasizes the importance of this discovery.

“Several upcoming programs such as Euclid, the Roman Space Telescope, and the Rubin Observatory Legacy Survey of Space and Time are sure to find many more examples in the years ahead, which will provide demographic properties across environments,” the authors conclude.

Sand presented these results at the recent 245th Meeting of the American Astronomical Society. Find them at the 32:00 mark of this video.

The post The Star-Forming Party Ended Early in Isolated Dwarf Galaxies appeared first on Universe Today.

A brain-computer interface, surgically placed in a research participant with tetraplegia, paralysis in all four limbs, provided an unprecedented level of control over a virtual quadcopter -- just by thinking about moving his unresponsive fingers.

Water desalination plants could replace expensive chemicals with new carbon cloth electrodes that remove boron from seawater, an important step of turning seawater into safe drinking water.

A new computational method gleans more information than its predecessors from maps showing how galaxies are clustered and threaded throughout the universe.

A new computational method gleans more information than its predecessors from maps showing how galaxies are clustered and threaded throughout the universe.

Scientists have developed a computing chip that can learn, correct errors, and process AI tasks.

An interdisciplinary team has developed a groundbreaking technology that addresses key limitations in clean hydrogen production using microwaves. They have also successfully elucidated the underlying mechanism of this innovative process.

Transition metals have long been used as catalysts to activate small molecules and turn them into valuable products. However, as these metals can be expensive and less abundant, scientists are increasingly looking at more common elements as alternatives. In a recent study, researchers used a concept called 'frustrated Lewis pairs' to develop a transition metal-free catalyst for activating hydrogen. This breakthrough could lead to more sustainable, cost-effective, and efficient chemical processes.

Astronomers have discovered extremely powerful winds pummeling the equator of WASP-127b, a giant exoplanet. Reaching speeds up to 33,000 km/h, the winds make up the fastest jet-stream of its kind ever measured on a planet. The discovery provides unique insights into the weather patterns of a distant world.

If you've ever tossed a generous pinch of salt into your pasta pan's water for flavor or as an attempt to make it boil faster, you've likely ended up with a whitish ring of deposits inside the pan. A group of scientists, inspired by this observation during an evening of board games and pasta dinner, wondered what it would take to create the most beautiful salt ring inside the pasta pan they report their findings about what causes these peculiar salt particle cloud deposits to form.