The European Space Agency (ESA) is hosting a one-hour livestream on YouTube on June 2, 2023, to celebrate the 20th birthday of the Mars Express mission. Using the Visual Monitoring Camera (VMC), images will be streamed directly from Mars to Earth roughly every 50 seconds, marking a first in space livestreaming. Credit: ESA

The European Space Agency (ESA) is hosting a one-hour Mars livestream on June 2, 2023, for the 20th anniversary of Mars Express. Direct images from Mars will be broadcast roughly every 50 seconds via the Visual Monitoring Camera, marking a first in space livestreaming. Despite an 18-minute delay due to light travel and signal processing, this initiative will bring Mars to Earth in as close to real-time as currently possible.

For one hour on Friday, June 2, 2023, join ESA on YouTube for a space first as live images stream down direct from Mars – this will be the closest you can get to a live view from the Red Planet.

Does Mars really exist? Yes, but we only have evidence of it as it was in the past, once light has bounced off it or is sent by orbiters and landers exploring it, and travels to Earth. Depending on the two planets’ relative positions in orbit around the Sun, this can take anywhere from 3 to 22 minutes.

In this way, there’s actually no such thing as ‘live’ news in space as we are limited by the speed of light traversing great distances.

But, on Friday, to celebrate the 20th birthday of ESA’s Mars Express, you’ll have the chance to get as close as it’s currently possible get to Mars. Tune in to be amongst the first to see new pictures roughly every 50 seconds as they’re beamed down directly from the Visual Monitoring Camera (VMC) on board ESA’s long-lived but-still-highly-productive Martian orbiter.

Get live updates via @esaoperations on Twitter and with the hashtag #MarsLIVE. Livestream starts 9:00 a.m. PDT (12:00 p.m. EDT, 18:00 CEST, 17:00 BST).

Finally, live on Mars

Most observations and data gathered by spacecraft are taken during periods when they are not in direct contact with a ground station antenna on Earth. Either because of geometry – for example, on the other side of the Sun or Mars – or the spacecraft’s antenna is pointing away from Earth while gathering science data.

For science, this is no problem. The data is stored on board and beamed down a few hours or even days later, once the spacecraft is in contact with the ground again. What normally happens for the Visual Monitoring Camera on Mars Express, is every couple of days a new batch are ‘downlinked’, processed, and made available to the world.

For most space missions, this works perfectly. Scientists then pore over the data that come in for years, discovering new secrets about the Universe. This makes ‘live’ footage rather rare.

In fact, there are only a few examples in the history of spaceflight; including NASA’s DART and LCROSS missions which filmed the view as they intentionally crashed into asteroid Dimorphos and the Moon, respectively, and of course, the Apollo missions sent back spectacular live video that captured the globe, showing astronauts walking on the Moon’s surface.

These missions were all pretty close to home and others farther away sent perhaps an image or two in near real-time. When it comes to a lengthy livestream from deep space, this is a first.

The post ESA’s Mars Express: Live Streaming From Mars for the First Time appeared first on Tekh Decoded.

Lead Image: The James Webb Space Telescope is revolutionizing our understanding of galaxy evolution in the early universe through redshift analysis and advanced imaging techniques, leading to significant discoveries and emphasizing the need for precise spectroscopic data. Credit: SciTechDaily.com

Using redshift and photometry, NASA’s James Webb Space Telescope is uncovering the secrets of early galaxies, demonstrating the need for precise spectral data in understanding the universe’s history.

One of NASA’s James Webb Space Telescope’s science goals is to understand how galaxies in the early universe formed and evolved into much larger galaxies like our own Milky Way. This goal requires that we identify samples of galaxies at different moments in the universe’s history to explore how their properties evolve with time.

We asked Micaela Bagley, a postdoctoral fellow at the University of Texas at Austin, to explain how astronomers analyze light from distant galaxies and determine “when in the universe’s history” we are observing them.

“Light takes time to travel through space. When light from a distant galaxy (or any object in space) reaches us, we are seeing that galaxy as it appeared in the past. To determine the  ‘when’ in the past, we use the galaxy’s redshift.

“Redshift tells us how long the light has spent being stretched to longer wavelengths by the expansion of the universe as it travels to reach us. We can calculate the redshift using features in the galaxy’s spectrum, which is an observation that spreads out the light from a target by wavelength, essentially sampling the light at very small intervals. We can measure the emission lines and spectral breaks (abrupt changes in the light intensity at specific wavelengths), and compare their observed wavelengths with their known emitted wavelengths.

“One of the most efficient ways to identify galaxies is through imaging, for example with the observatory’s NIRCam (Near-Infrared Camera) instrument. We take images using multiple filters to collect the object’s light in several different colors. When we measure a galaxy’s photometry, or how bright it is in an image, we’re measuring the brightness of the object averaged across the full range of wavelengths transmitted by the filter. We can observe a galaxy with NIRCam’s broadband imaging filters, but there is a lot of detailed information hidden within each single measurement for every 0.3–1.0 microns in wavelength coverage.

“Yet we can start to constrain the shape of a galaxy’s spectrum. The spectrum’s shape is affected by several properties including how many stars are forming in the galaxy, how much dust is present within it, and how much the galaxy’s light has been redshifted. We compare the measured brightness of the galaxy in each filter to the predicted brightness for a set of galaxy models spanning a range of those properties at a range of redshifts. Based on how well the models fit the data, we can determine the probability that the galaxy is at a given redshift or ‘ moment in history.’ The best-fitting redshift determined through this analysis is called the photometric redshift.

“In July 2022, teams used NIRCam images from the CEERS Survey to identify two galaxies with photometric redshifts greater than 11 (when the universe was less than 420 million years old.) Neither of these objects were detected by NASA’s Hubble Space Telescope observations in this field because they are either too faint or are detectable only at wavelengths outside of Hubble’s sensitivity. These were very exciting discoveries with the new telescope!

“However, photometric redshift of a galaxy is somewhat uncertain. For example, we may be able to determine that a spectral break is present in a filter, but not the precise wavelength of the break. While we can estimate a best-fit redshift based on modeling the photometry, the resulting probability distribution is often broad. Additionally, galaxies at different redshifts can have similar colors in broadband filters, making it difficult to distinguish their redshifts based only on photometry. For example, red, dusty galaxies at redshifts less than 5 (or when the universe was 1.1 billion years old or older) and cool stars in our own galaxy can sometimes mimic the same colors of a high-redshift galaxy. We therefore consider all galaxies that are selected based on their photometric redshifts to be high-redshift candidates until we can obtain a more precise redshift.

“We can determine a more precise redshift for a galaxy by obtaining a spectrum. As illustrated in the following figure, our calculation of the redshift probability distribution improves as we measure the photometry of a galaxy in ever finer wavelength steps. The probability distribution narrows as we move from using broadband filters for imaging (top) to a larger number of narrower filters (middle), to a spectrum (bottom). In the bottom row we can start to key off specific features like the spectral break on the far left and emission lines to obtain a redshift probability distribution that is very precise – a spectroscopic redshift.

“In February 2023, the CEERS teams followed up their high-redshift candidates with observatory’s NIRSpec (Near-Infrared Spectrograph) instrument to measure precise, spectroscopic redshifts. One candidate (Maisie’s Galaxy) has been confirmed to be at redshift 11.4 (when the universe was 390 million years old), while the second candidate was discovered to actually be at a lower redshift of 4.9 (when the universe was 1.2 billion years old.)

About the Author:

Micaela Bagley is a postdoctoral fellow at the University of Texas at Austin and a member of CEERS. They study galaxy formation and evolution in the early universe. Micaela is also responsible for processing all the NIRCam images for the CEERS team.

The post Redshift Riddles: Decoding Distance With Space Telescopes appeared first on Tekh Decoded.

Lead Image: Researchers conducted a novel study on the runaway greenhouse effect, revealing how a critical threshold of water vapor can lead to catastrophic climate changes on Earth and other planets. The research reveals a significant cloud pattern that contributes to this irreversible climate change, providing insights into exoplanet climates and their potential to support life.

A team from UNIGE together with CNRS has managed to simulate the entire runaway greenhouse effect, which can make a planet completely unhabitable.

The Earth is a wonderful blue and green dot covered with oceans and life, while Venus is a yellowish sterile sphere that is not only inhospitable but also sterile. However, the difference between the two bears to only a few degrees in temperature.

A team of astronomers from the University of Geneva (UNIGE) and members of the National Centre of Competence in Research (NCCR) PlanetS, with the support of the CNRS laboratories of Paris and Bordeaux, has achieved a world’s first by managing to simulate the entirety of the runaway greenhouse process which can transform the climate of a planet from idyllic and perfect for life, to a place more than harsh and hostile.

The scientists have also demonstrated that from initial stages of the process, the atmospheric structure and cloud coverage undergo significant changes, leading to an almost-unstoppable and very complicated to reverse runaway greenhouse effect. On Earth, a global average temperature rise of just a few tens of degrees, subsequent to a slight rise of the Sun’s luminosity, would be sufficient to initiate this phenomenon and to make our planet inhabitable.

Greenhouse Effect and Runaway Scenario

The idea of a runaway of the greenhouse effect is not new. In this scenario, a planet can evolve from a temperate state like on Earth to a true hell, with surface temperatures above 1000°C. The cause? Water vapor, a natural greenhouse gas. Water vapor prevents the solar irradiation absorbed by Earth to be reemitted towards the void of space, as thermal radiation. It traps heat a bit like a rescue blanket. A dash of greenhouse effect is useful – without it, Earth would have an average temperature below the freezing point of water, looking like a ball covered with ice and hostile to life.

On the opposite, too much greenhouse effect increases the evaporation of oceans, and thus the amount of water vapor in the atmosphere. “There is a critical threshold for this amount of water vapor, beyond which the planet cannot cool down anymore. From there, everything gets carried away until the oceans end up getting fully evaporated and the temperature reaches several hundred degrees,” explains Guillaume Chaverot, former postdoctoral scholar in the Department of Astronomy at the UNIGE Faculty of Science and main author of the study.

Groundbreaking Study on Climate Transition

“Until now, other key studies in climatology have focused solely on either the temperate state before the runaway, or either the inhabitable state post-runaway,” reveals Martin Turbet, researcher at CNRS laboratories of Paris and Bordeaux, and co-author of the study. “It is the first time a team has studied the transition itself with a 3D global climate model, and has checked how the climate and the atmosphere evolve during that process.”

One of the key points of the study describes the appearance of a very peculiar cloud pattern, increasing the runaway effect, and making the process irreversible. “From the start of the transition, we can observe some very dense clouds developing in the high atmosphere. Actually, the latter does not display anymore the temperature inversion characteristic of the Earth atmosphere and separating its two main layers: the troposphere and the stratosphere. The structure of the atmosphere is deeply altered,” points out Guillaume Chaverot.

Serious Consequences for the Search of Life Elsewhere

This discovery is a key feature for the study of climate on other planets, and in particular on exoplanets – planets orbiting other stars than the Sun. “By studying the climate on other planets, one of our strongest motivations is to determine their potential to host life,” indicates Émeline Bolmont, assistant professor and director of the UNIGE Life in the Universe Center (LUC), and co-author of the study.

The LUC leads state-of-the-art interdisciplinary research projects regarding the origins of life on Earth, and the quest for life elsewhere in our solar system and beyond, in exoplanetary systems. “After the previous studies, we suspected already the existence of a water vapor threshold, but the appearance of this cloud pattern is a real surprise!” discloses Émeline Bolmont. “We have also studied in parallel how this cloud pattern could create a specific signature, or ‘‘fingerprint’’, detectable when observing exoplanet atmospheres. The upcoming generation of instruments should be able to detect it,” unveils Martin Turbet. The team is also not aiming to stop there, Guillaume Chaverot having received a research grant to continue this study at the “Institut de Planétologie et d’Astrophysique de Grenoble” (IPAG). This new step of the research project will focus on the specific case of the Earth.

A Planet Earth in a Fragile Equilibrium

With their new climate models, the scientists have calculated that a very small increase of the solar irradiation – leading to an increase of the global Earth temperature, of only a few tens of degrees – would be enough to trigger this irreversible runaway process on Earth and make our planet as inhospitable as Venus. One of the current climate goals is to limit global warming on Earth, induced by greenhouse gases, to only 1.5 degrees by 2050. One of the questions of Guillaume Chaverot’s research grant is to determine if greenhouse gases can trigger the runaway process as a slight increase of the Sun luminosity might do. If so, the next question will be to determine if the treshold temperatures are the same for both processes.

The Earth is thus not so far from this apocalyptical scenario. “Assuming this runaway process would be started on Earth, an evaporation of only 10 meters of the oceans’ surface would lead to a 1 bar increase of the atmospheric pressure at ground level. In just a few hundred years, we would reach a ground temperature of over 500°C. Later, we would even reach 273 bars of surface pressure and over 1 500°C, when all of the oceans would end up totally evaporated,” concludes Guillaume Chaverot.

Reference: “First exploration of the runaway greenhouse transition with a 3D General Circulation Model” by Guillaume Chaverot, Emeline Bolmont and Martin Turbet, 18 December 2023, Astronomy & Astrophysics.
DOI: 10.1051/0004-6361/202346936

Exoplanets in Geneva: 25 Years of Expertise Honored With a Nobel Prize

The first exoplanet was discovered in 1995 by two researchers from the University of Geneva, Michel Mayor and Didier Queloz, recipients of the 2019 Nobel Prize in Physics. This discovery put the University of Geneva’s Astronomy Department at the forefront of research in the field, with the construction and installation of HARPS on ESO’s 3.6m telescope at La Silla in 2003.

For two decades, this spectrograph was the most powerful in the world for determining the mass of exoplanets. However, HARPS was surpassed in 2018 by ESPRESSO, another spectrograph built in Geneva and installed on the Very Large Telescope (VLT) in Paranal, Chile.

Switzerland is also involved in space-based observations of exoplanets with the CHEOPS mission, the result of two national areas of expertise: the space know-how of the University of Bern, in collaboration with its counterpart in Geneva, and the ground-based experience of the University of Geneva, assisted by its counterpart in the Swiss capital. These two areas of scientific and technical expertise have also led to the creation of the PlanetS National Centre of Competence in Research (NCCR).

Life in the Universe Center (LUC): An Interdisciplinary Excellence Pole

The Life in the Universe Center (LUC) is an interdisciplinary research center of the University of Geneva (UNIGE) founded in 2021 following the awarding in 2019 of the Nobel Prize in Physics by professors Michel Mayor and Didier Queloz. Thanks to the progress made during the last decade, both in the domains of the solar system exploration, of exoplanets and of the organic structure of life, the question of the emergence of life on other planets can now be tackled in a tangible way, and no more only speculatively. At the crossroads of astronomy, chemistry, physics, biology and of Earth and climate sciences, the LUC has for objective to understand the origins and the distribution of life in the universe. At the initiative of the Astronomy Department, the LUC brings together researchers from numerous UNIGE institutes and departments, as well as from several partner universities internationally.

The post Temperate to Terrifying: Decoding Exoplanet Climate Catastrophes appeared first on Tekh Decoded.

Lead Image: Scientists have employed artificial intelligence to analyze over a billion waves spanning 700 years, leading to a groundbreaking formula for predicting rogue waves. This study, which transforms vast ocean data into an equation for rogue wave probability, challenges previous theories and offers significant implications for maritime safety. The research’s accessibility and AI’s role in enhancing human understanding mark a significant advancement in the field. Credit: SciTechDaily.com

Utilizing seven centuries of oceanic wave data, encompassing over a billion wave observations, researchers from the University of Copenhagen and the University of Victoria have employed advanced artificial intelligence techniques to find a formula for how to predict the occurrence of these maritime monsters.

Long believed to be mere myths, freakishly large rogue waves are very real and can split apart ships and even damage oil rigs. By analyzing seven centuries’ worth of data from over a billion ocean waves, researchers from the University of Copenhagen and the University of Victoria have employed artificial intelligence to devise a predictive formula for these formidable sea giants. The new knowledge can make shipping safer.

Stories about monster waves, called rogue waves, have been the lore of sailors for centuries. But when a 26-metre-high rogue wave slammed into the Norwegian oil platform Draupner in 1995, digital instruments were there to capture and measure the North Sea monster. It was the first time that a rogue had been measured and provided scientific evidence that abnormal ocean waves really do exist.

Since then, these extreme waves have been the subject of much study. And now, researchers from the University of Copenhagen’s Niels Bohr Institute have used AI methods to discover a mathematical model that provides a recipe for how – and not least when – rogue waves can occur.

With the help of enormous amounts of big data about ocean movements, researchers can predict the likelihood of being struck by a monster wave at sea at any given time.

“Basically, it is just very bad luck when one of these giant waves hits. They are caused by a combination of many factors that, until now, have not been combined into a single risk estimate. In the study, we mapped the causal variables that create rogue waves and used artificial intelligence to gather them in a model that can calculate the probability of rogue wave formation,” says Dion Häfner.

Häfner is a former Ph.D. student at the Niels Bohr Institute and first author of the scientific study, which has just been published in the prestigious journal Proceedings of the National Academy of Sciences (PNAS).

Rogue waves happen every day

In their model, the researchers combined available data on ocean movements and the sea state, as well as water depths and bathymetric information. Most importantly, wave data was collected from buoys in 158 different locations around US coasts and overseas territories that collect data 24 hours a day. When combined, this data – from more than a billion waves – contains 700 years’ worth of wave height and sea state information.

The researchers analyzed the many types of data to find the causes of rogue waves, defined as being waves that are at least twice as high as the surrounding waves – including extreme rogue waves that can be over 20 meters high. With machine learning, they transformed it all into an algorithm that was then applied to their dataset.

“Our analysis demonstrates that abnormal waves occur all the time. In fact, we registered 100,000 waves in our dataset that can be defined as rogue waves. This is equivalent to around 1 monster wave occurring every day at any random location in the ocean. However, they aren’t all monster waves of extreme size,” explains Johannes Gemmrich, the study’s second author.

Artificial intelligence as a scientist

In the study, the researchers were helped by artificial intelligence. They used several AI methods, including symbolic regression which gives an equation as output, rather than just returning a single prediction as traditional AI methods do.

By examining more than 1 billion waves, the researchers’ algorithm has analyzed its own way into finding the causes of rogue waves and condensed it into equation that describes the recipe for a rogue wave. The AI learns the causality of the problem and communicates that causality to humans in the form of an equation that researchers can analyze and incorporate into their future research.

“Over decades, Tycho Brahe collected astronomical observations from which Kepler, with lots of trial and error, was able to extract Kepler’s Laws. Dion used machines to do with waves which Kepler did with planets. For me, it is still shocking that something like this is possible,” says Markus Jochum.

Phenomenon known since the 1700s

The new study also breaks with the common perception of what causes rogue waves. Until now, it was believed that the most common cause of a rogue wave was when one wave briefly combined with another and stole its energy, causing one big wave to move on.

However, the researchers establish that the most dominant factor in the materialization of these freak waves is what is known as “linear superposition”. The phenomenon, known since the 1700s, occurs when two wave systems cross over each other and reinforce one another for a brief period of time.

“If two wave systems meet at sea in a way that increases the chance to generate high crests followed by deep troughs, the risk of extremely large waves arises. This is knowledge that has been around for 300 years and which we are now supporting with data,” says Dion Häfner.

Safer shipping

The researchers’ algorithm is good news for the shipping industry, which at any given time has roughly 50,000 cargo ships sailing around the planet. Indeed, with the help of the algorithm, it will be possible to predict when this “perfect” combination of factors is present to elevate the risk of a monster wave that could pose a danger for anyone at sea.

“As shipping companies plan their routes well in advance, they can use our algorithm to get a risk assessment of whether there is a chance of encountering dangerous rogue waves along the way. Based on this, they can choose alternative routes,” says Dion Häfner.

Both the algorithm and research are publicly available, as are the weather and wave data deployed by the researchers. Therefore, Dion Häfner says that interested parties, such as public authorities and weather services, can easily begin calculating the probability of rogue waves. And unlike many other models created using artificial intelligence, all of the intermediate calculations in the researchers’ algorithm are transparent.

“AI and machine learning are typically black boxes that don’t increase human understanding. But in this study, Dion used AI methods to transform an enormous database of wave observations into a new equation for the probability of rogue waves, which can be easily understood by people and related to the laws of physics,” concludes Professor Markus Jochum, Dion’s thesis supervisor and co-author.

Reference: “Machine-guided discovery of a real-world rogue wave model” by Dion Häfner, Johannes Gemmrich and Markus Jochum, 20 November 2023, Proceedings of the National Academy of Sciences.
DOI: 10.1073/pnas.2306275120

The post Navigating Maritime Monsters: AI Formula Cracks the Code of Rogue Waves appeared first on Tekh Decoded.

Lead Image: CU Boulder researchers have innovated a new imaging method using doughnut-shaped light beams, advancing the field of ptychography. This technique allows for detailed imaging of tiny, regularly patterned structures like semiconductors, overcoming previous limitations of traditional microscopy. This advancement promises significant improvements in nanoelectronics and biological imaging. (Artist’s concept.) Credit: SciTechDaily.com

In a new study, researchers at CU Boulder have used doughnut-shaped beams of light to take detailed images of objects too tiny to view with traditional microscopes.

Advancements in Nanoelectronics Imaging

The new technique could help scientists improve the inner workings of a range of “nanoelectronics,” including the miniature semiconductors in computer chips. The discovery was highlighted on December 1 in a special issue of Optics & Photonics News called Optics in 2023.

Ptychography: A Lens into the Microscopic World

The research is the latest advance in the field of ptychography, a difficult to pronounce (the “p” is silent) but powerful technique for viewing very small things. Unlike traditional microscopes, ptychography tools don’t directly view small objects. Instead, they shine lasers at a target, then measure how the light scatters away—a bit like the microscopic equivalent of making shadow puppets on a wall.

Overcoming the Ptychography Challenge

So far, the approach has worked remarkably well, with one major exception, said study senior author and Distinguished Professor of physics Margaret Murnane.

“Until recently, it has completely failed for highly periodic samples, or objects with a regularly repeating pattern,” said Murnane, fellow at JILA, a joint research institute of CU Boulder and the National Institute of Standards and Technology (NIST). “It’s a problem because that includes a lot of nanoelectronics.”

She noted that many important technologies like some semiconductors are made up of atoms like silicon or carbon joined together in regular patterns like a small grid or mesh. To date, those structures have proved tricky for scientists to view up close using ptychography.

Breakthrough With Doughnut-Shaped Light

In the new study, however, Murnane and her colleagues came up with a solution. Instead of using traditional lasers in their microscopes, they produced beams of extreme ultraviolet light in the shape of doughnuts.

The team’s novel approach can collect accurate images of tiny and delicate structures that are roughly 10 to 100 nanometers in size, or many times smaller than a millionth of an inch. In the future, the researchers expect to zoom in to view even smaller structures. The doughnut, or optical angular momentum, beams also won’t harm tiny electronics in the process—as some existing imaging tools, like electron microscopes, sometimes can.

“In the future, this method could be used to inspect the polymers used to make and print semiconductors for defects, without damaging those structures in the process,” Murnane said.

Bin Wang and Nathan Brooks, who earned their doctoral degrees from JILA in 2023, were first authors of the new study.

Pushing the Limits of Microscopes

The research, Murnane said, pushes the fundamental limits of microscopes: Because of the physics of light, imaging tools using lenses can only see the world down to a resolution of about 200 nanometers—which isn’t accurate enough to capture many of the viruses, for example, that infect humans. Scientists can freeze and kill viruses to view them with powerful cryo-electron microscopes, but can’t yet capture these pathogens in action and in real time.

Ptychography, which was pioneered in the mid-2000s, could help researchers push past that limit.

The Mechanics of Ptychography

To understand how, go back to those shadow puppets. Imagine that scientists want to collect a ptychographic image of a very small structure, perhaps letters spelling out “CU.” To do that, they first zap a laser beam at the letters, scanning them multiple times. When the light hits the “C” and the “U” (in this case, the puppets), the beam will break apart and scatter, producing a complex pattern (the shadows). Employing sensitive detectors, scientists record those patterns, then analyze them with a series of mathematical equations. With enough time, Murnane explained, they recreate the shape of their puppets entirely from the shadows they cast.

“Instead of using a lens to retrieve the image, we use algorithms,” Murnane said.

She and her colleagues have previously used such an approach to view submicroscopic shapes like letters or stars.

But the approach won’t work with repeating structures like those silicon or carbon grids. If you shine a regular laser beam on a semiconductor with such regularity, for example, it will often produce a scatter pattern that is incredibly uniform—ptychographic algorithms struggle to make sense of patterns that don’t have much variation in them.

The problem has left physicists scratching their heads for close to a decade.

Doughnut Microscopy

In the new study, however, Murnane and her colleagues decided to try something different. They didn’t make their shadow puppets using regular lasers. Instead, they generated beams of extreme ultraviolet light, then employed a device called a spiral phase plate to twist those beams into the shape of a corkscrew, or vortex. (When such a vortex of light shines on a flat surface, it makes a shape like a doughnut.)

The doughnut beams didn’t have pink glaze or sprinkles, but they did the trick. The team discovered that when these types of beams bounced off repeating structures, they created much more complex shadow puppets than regular lasers.

To test out the new approach, the researchers created a mesh of carbon atoms with a tiny snap in one of the links. The group was able to spot that defect with precision not seen in other ptychographic tools.

“If you tried to image the same thing in a scanning electron microscope, you would damage it even further,” Murnane said.

Advancing Towards Finer Details

Moving forward, her team wants to make their doughnut strategy even more accurate, allowing them to view smaller and even more fragile objects—including, one day, the workings of living, biological cells.

Reference: “High-fidelity ptychographic imaging of highly periodic structures enabled by vortex high harmonic beams” by Michael Tanksalvala, Henry C. Kapteyn, Bin Wang, Peter Johnsen, Yuka Esashi, Iona Binnie, Margaret M. Murnane, Nicholas W. Jenkins and Nathan J. Brooks, 19 September 2023, Optica.
DOI: doi:10.1364/OPTICA.498619

Other co-authors of the new study include Henry Kapteyn, professor of physics and fellow of JILA, and current and former JILA graduate students Peter Johnsen, Nicholas Jenkins, Yuka Esashi, Iona Binnie and Michael Tanksalvala.

The post Tiny Wonders Revealed: How “Doughnut” Light Beams Unlock Microscopic Mysteries appeared first on Tekh Decoded.

Lead Image: Researchers have studied the Ciomadul volcano to understand how long-dormant volcanoes can suddenly erupt. Their findings on the chemical and mineral composition of the magma provide valuable insights into volcanic reactivation and eruption forecasting, highlighting the potential dangers of inactive volcanoes. Credit: SciTechDaily.com

Even in a quiet dormant phase, a volcano can rapidly become active and its eruption can pose a previously unknown threat to the surrounding area.

Can a volcano erupt after tens of thousands of years of dormancy? If so, how can this be explained and what makes volcanic eruptions more dangerous, i.e. explosive? These are key questions in volcanic hazard assessment and can also draw attention to volcanoes that appear to be inactive. Even in a quiet dormant phase, a volcano can rapidly become active and its eruption can pose a previously unknown threat to the surrounding area. New research by Hungarian scientists is helping to reveal the signs before such a volcano erupts.

A team from the ELTE Eötvös Loránd University, Institute of Geography and Earth Sciences, and the HUN-REN-ELTE Volcanology Research Group, in cooperation with other scientists from Europe, studied Ciomadul, the youngest volcano in the Carpathian-Pannonian region.

Using high-resolution integrated mineral texture and chemical composition data, they quantified the conditions of magma evolution, reconstructed the architecture of the subvolcanic magma reservoir, identified the characteristics of the resident crystal mush and the recharge magmas, which triggered the eruptions, and explained why volcanic activity in the last active period became predominantly explosive.

Ciomadul: A Typical Long Dormant Volcano

The eruptive history of Ciomadul was previously revealed by the research team using U-Th-Pb-He geochronology of a tiny crystal, zircon. Szabolcs Harangi, professor and leader of the research project, emphasized that “there have been several long periods of dormancy in the almost million-year life of the volcano, but even after tens of thousands, sometimes even more than 100,000 years of quiescence, volcanic eruptions started again!”

The most significant volcanism took place in the last 160,000 years, with lava domes extrusions between 160 and 95 thousand years ago, and then, after more than 30 thousand years of dormancy, eruptions resumed 56 thousand years ago.

Barbara Cserép, a PhD student at ELTE, is studying the youngest eruption products: “They were formed by more dangerous, explosive eruptions compared to the previous active episode. So, it is important to know what was the reason for this change in eruption style!” The last volcanic eruptions occurred 30,000 years ago, and since then the volcano has been dormant again.

A Petrodetective Work

The cause of the volcanic eruption initiation and the processes that control the eruption style are hidden in the rocks formed during the volcanic activity. These can be revealed by the detailed study of the rock-forming minerals. The research team determined the chemical composition of all the mineral phases, often at high resolution from the crystal core to the rim, in the pumices formed during the explosive volcanism from 56 to 30,000 years ago.

They then critically evaluated the results of various methods for calculating crystallization temperature, pressure, redox state, melt composition and melt water content to quantify the magma conditions and also to constrain how these crystals were incorporated into the erupting magma. This helped to unravel the architecture of the magma reservoir system, the processes that lead to eruptions, and to explain the explosive eruptions.

The Key to Explosive Eruptions

The key player in this petrodetective study was a mineral, called amphibole. “Many elements can enter into the crystal lattice of amphibole, but the element substitutions are strongly controlled by the magma conditions” explains Barbara Cserép. The chemical composition of amphibole in the Ciomadul pumices shows a large variation even in single sample. Some amphiboles represent a low-temperature, highly crystalline magma reservoir at depths of 8-12 kilometers, but most of them were transported to this shallow magma storage by higher-temperature recharge magmas coming from greater depths.

“Compared to the previous, lava dome-forming eruptive period, these fresh recharge magmas carried amphibole with a distinct composition, i.e. these magmas were slightly different, and this could play an important role in why the eruption became explosive,” Harangi points out.

“We identified several amphiboles with a chemical composition not reported in volcanic rocks from other volcanoes,” adds Cserép, as an important result of the research. They interpreted such amphibole as an early crystallization phase in ultra-hydrous magmas, and these water-rich recharge magmas may have played a key role in triggering the explosive eruptions.

The composition of the outermost rim of the crystals and of the iron-titanium oxides provided information about the magma condition just prior to the eruptions. Postdoctoral researcher Máté Szemerédi, another lead author of the study, said, “The composition of iron-titanium oxides equilibrates in a few days when the magma condition changes; they indicate that the erupted magma was at 800-830 degrees Celsius and was oxidized.”

The Importance of the Ciomadul Volcano

At present, the Ciomadul volcano shows no signs for reawakening. However, this study also points out that reactivation can occur rapidly, within weeks or months, in case of recharge by hot, hydrous magma. Quantitative volcano petrology studies are important to reconstruct the subvolcanic magma reservoir structure and the magma storage conditions, which can also help us in eruption forecasting to better understand the pre-eruption signals.

“This research is novel in the sense that it is performed in a long-dormant volcano, and as a result, the Ciomadul volcano is receiving an increasing international attention,” Szabolcs Harangi points out. This helps to highlight that, in addition to the 1500 or so potentially active volcanoes on Earth, long-dormant volcanoes can also pose a previously not recognized hazard, especially if there is still melt-bearing magma beneath them.

Reference: “Constraints on the pre-eruptive magma storage conditions and magma evolution of the 56–30 ka explosive volcanism of Ciomadul (East Carpathians, Romania)” by Barbara Cserép, Máté Szemerédi, Szabolcs Harangi, Saskia Erdmann, Olivier Bachmann, István Dunkl, Ioan Seghedi, Katalin Mészáros, Zoltán Kovács, Attila Virág, Theodoros Ntaflos, David Schiller, Kata Molnár and Réka Lukács, 28 November 2023, Contributions to Mineralogy and Petrology.
DOI: 10.1007/s00410-023-02075-z

The post Think That Volcano Is Asleep? Think Again: Explosive Secrets Unveiled appeared first on Tekh Decoded.

Lead Image: A Stanford study using genetic and molecular tools has unraveled the mystery of starfish anatomy, revealing that their “head” is distributed across multiple regions, including the center and each limb. This finding challenges traditional understanding and suggests a complex evolutionary history. The research, exploring the transformation from bilateral to pentaradial body plans, emphasizes the importance of studying diverse life forms to gain insights into evolutionary biology.

If you put a hat on a starfish, where would you put it? On the center of the starfish? Or on the point of an arm and, if so, which one? The question is silly, but it gets at serious questions in the fields of zoology and developmental biology that have perplexed veteran scientists and schoolchildren in introductory biology classes alike: Where is the head on a starfish? And how does their body layout relate to ours?

Now, a new Stanford study that used genetic and molecular tools to map out the body regions of starfish – by creating a 3D atlas of their gene expression – helps answer this longstanding mystery. The “head” of a starfish, the researchers found, is not in any one place. Instead, the headlike regions are distributed with some in the center of the sea star as well as in the center of each limb of its body.

“The answer is much more complicated than we expected,” said Laurent Formery, lead author and postdoc in the labs of Christopher Lowe at the Stanford School of Humanities and Sciences and Daniel S. Rokhsar at the University of California, Berkeley. “It is just weird, and most likely the evolution of the group was even more complicated than this.”

Starfish (sea stars) belong to a group of animals called echinoderms. Echinoderms and humans are closely related, yet the life cycle and anatomy of sea stars are very different from ours.

Sea stars begin life as fertilized eggs that hatch into a free-floating larva. The larvae bob in the ocean in a plankton form for weeks to months before settling to the ocean floor to perform a magic trick of sorts – transforming from a bilateral (symmetric across the midline) body plan into an adult with a five-point star shape called a pentaradial body plan.

“This has been a zoological mystery for centuries,” said Lowe, who is also a researcher at Hopkins Marine Station and senior author of the paper that was recently published in the journal Nature. “How can you go from a bilateral body plan to a pentaradial plan, and how can you compare any part of the starfish to our own body plan?”

Mapping stars

For puzzles such as this one, researchers often conduct comparative studies to identify similar structures in related groups of animals to glean clues about the evolutionary events that prompted the trait of interest.

“The problem with starfish is there is nothing on a starfish anatomically that you can relate to a vertebrate,” said Lowe. “There is just nothing there.”

At least, nothing on the outside of a starfish. And that is where genetic and molecular techniques come in.

During his graduate research, Formery studied early development in sea urchins – echinoderms, like sea stars, that also start their life as bilateral larvae before transforming into adults with fivefold symmetry. When Formery joined Lowe’s lab, Formery’s knowledge of echinoderm development combined with Lowe’s expertise in molecular biology techniques to help tackle the mystery of sea stars’ baffling body plan.

The team used a group of well-studied molecular markers (Hox genes are an example) that act as blueprints for an organism’s body plan by “telling” each cell which body region it belongs to.

“If you strip away the skin of an animal and look at the genes involved in defining a head from a tail, the same genes code for these body regions across all groups of animals,” said Lowe. “So we ignored the anatomy and asked: Is there a molecular axis hidden under all this weird anatomy and what is its role in a starfish forming a pentaradial body plan?”

To investigate this question, the researchers used RNA tomography, a technique that pinpoints where genes are expressed in tissue, and in situ hybridization, a technique that zeroes in on a specific RNA sequence in a cell.

“First we sectioned sea star arms into thin slices from tip to center, top to bottom, and left to right,” said Formery, noting that sea stars regenerate missing limbs. “We used RNA tomography to determine which genes were expressed in each slice and then ‘reassembled’ the slices using computer models. This gave us a 3D map of gene expression.”

“In the second method, in situ hybridization chain reaction, we stained sea star tissue and visually inspected the samples to see where a gene was expressed,” said Formery. This enabled the researchers to examine anterior-posterior (head to tail) body patterning in the outermost layer of cells called the ectoderm.

“This was made possible by the recent, big, technical improvement in in situ hybridization, known as in situ hybridization chain reaction, Formery said. “This new method provides better resolution of where the gene is expressed.”

The research revealed that sea stars have a headlike territory in the center of each “arm” and a tail-like region along the perimeter. In an unexpected twist, no part of the sea star ectoderm expresses a “trunk” genetic patterning program, suggesting that sea stars are mostly headlike.

Mining truly diverse biodiversity

Research is often centered on groups of animals that look like us, the researchers explained. But if we focus on the familiar, we are less likely to learn something new.

“There are 34 different animal phyla living on this planet and in over roughly 600 million years they have all come up with different solutions to the same fundamental biological problems,” Lowe said. “Most animals don’t have spectacular nervous systems and are out chasing prey – they are modest animals that live in burrows in the ocean. People are generally not drawn to these animals, and yet they probably represent how much of life got started.”

This study demonstrates how a comparative approach that uses genetic and molecular techniques can be used to mine biodiversity for insights into why different animals look the way they do and how their body plans evolved.

“Even in recent molecular papers there’s a question mark near echinoderms on the evolutionary tree because we don’t know much about them,” Formery said. “It was nice to show that – at least at the molecular level – we have a new piece of the puzzle that can now be put on the tree.”

Reference: “Molecular evidence of anteroposterior patterning in adult echinoderms” by L. Formery, P. Peluso, I. Kohnle, J. Malnick, J. R. Thompson, M. Pitel, K. R. Uhlinger, D. S. Rokhsar, D. R. Rank and C. J. Lowe, 32 October 2023, Nature.
DOI: 10.1038/s41586-023-06669-2

Formery, Lowe, and Rokhsar are also researchers at the Chan Zuckerberg BioHub. Rokhsar is also a researcher at the Okinawa Institute of Science and Technology. Additional Stanford co-authors are Ian Kohnle, Judith Malnick, and Kevin Uhlinger of Hopkins Marine Station. Additional authors are from Pacific Biosciences in Menlo Park, California, and Columbia Equine Hospital in Gresham, Oregon.

This research was funded by NASA, the National Science Foundation, and the Chan Zuckerberg BioHub.

The post Mysterious Anatomy Unraveled – Stanford Scientists Uncover Location of Starfish’s Head appeared first on Tekh Decoded.

Researchers have mapped over 2.3 million brain cells from mice, shedding light on how different brain cell types are formed through gene regulation. This work, part of a larger effort to create a detailed brain cell atlas, has significant implications for understanding brain function and treating neuropsychiatric disorders.

UC San Diego researchers are translating the language of brain cells, and it’s helping them figure out what goes wrong in diseases of the brain.

Despite all our cells sharing the same DNA, there are thousands of different cell types in the human brain, each with a unique structure and function. One longstanding problem in neuroscience is determining how genes are switched on and off to form the mosaic of different cell types within the brain. Today, scientists from University of California San Diego School of Medicine have published two new studies that bring us closer to solving this mystery.

Innovative Studies Unveil Brain’s Genetic Secrets

The researchers analyzed more than 2.3 million individual brain cells from mice to create a comprehensive map of the mouse brain and used artificial intelligence to help predict what stretches of DNA are used to determine a brain cell’s type. The researchers also looked at the brains of humans and primates to study the evolution of the processes cells use to turn genes on and off. The findings will be published on December 14, 2023, in a special edition of the journal Nature.

Understanding the Brain’s Molecular Language

“A cell’s DNA is like its language,” said senior author Bing Ren, PhD, professor at UC San Diego School of Medicine. “Just like there are certain root words that many languages share, there are certain genes and gene expression patterns that are conserved across different species. Learning to understand and interpret the brain’s molecular language can help us learn more about how the brain works in general and about what happens to the brain in neuropsychiatric conditions.”

Comprehensive Brain Cell Atlas and the BRAIN Initiative

The two new papers are part of a package of 10 studies describing the first complete cell type atlas of a mammalian brain, led by researchers at UC San Diego, the Salk Institute for Biological Studies, the Allen Institute for Brain Science and other institutions. The research is part of the National Institutes of Health’s Brain Research Through Advancing Innovative Neurotechnologies® Initiative, or the BRAIN Initiative®, which launched in 2014 to deepen our understanding of the inner workings of the human mind and improve how we treat, prevent, and cure disorders of the brain.

“This work is helping us establish a baseline understanding of what the brain is like at the cellular level,” said Ren. “This will make it possible to draw comparisons between our baseline and brains with neurological and psychiatric disorders. Studying the brain this way could help us discover new therapeutic approaches for these conditions.”

The Cell Census Network and Its Findings

One of the most ambitious projects under the Brain Initiative is the Cell Census Network (BICNN), which seeks to describe human brain cells in unprecedented molecular detail, classifying them into more precise subtypes, pinpointing their locations in the brain and tracking how cellular features change over a lifetime. Earlier this year, Ren and other scientists from the BICCN published a first-of-its kind atlas of the human brain, which identified more than a hundred types of brain cell. Their new atlas of the mouse brain complements this work and expands upon it by drawing comparisons between the brains of different species.

For example, by comparing the brains of mice with those of humans and nonhuman primates, the researchers found that cell-type-specific patterns of gene expression evolve much more rapidly than patterns that are shared across cell types. This could help explain why there are so many different cell types in the brain.

“Humans have evolved over millions of years, and much of that evolutionary history is shared with other animals,” said Joseph Ecker, PhD, a professor at the Salk Institute for Biological Studies who co-led one of the new studies with Ren. “Data from humans alone is never going to be enough to tell us everything we want to know about how the brain works. By filling in these gaps with other mammalian species, we can continue to answer those questions and improve the machine-learning models we use by providing them more data.”

Relevance to Human Diseases

While the BRAIN Initiative and BICCN are still very much ongoing projects, some insights are already proving relevant to human diseases. For example, the researchers found that many of the genetic programs that determine cell type were in parts of the genome that have already been implicated in human diseases, such multiple sclerosis, anorexia nervosa and tobacco use disorder. This could help shed light on how neuropsychiatric disorders affect the brain.

“The brain isn’t homogenous, and diseases don’t affect all parts of the brain equally,” said Ren. “Insights from this research and the BRAIN initiative as a whole are helping us better understand what types of cells are affected in specific diseases. We hope this will pave the way for more precise, targeted therapies that can heal diseased cells without affecting the rest of the brain.”

References:

13 December 2023, Nature.
DOI: 10.1038/s41586-023-06824-9

Full link to first study:

Co-authors of the first study include: Songpeng Zu, Yang Eric Li, Kangli Wang, Ethan Armand, Sainath Mamde, Maria Luisa Amaral, Yuelai Wang, Andre Chu, Yang Xie, Michael Miller, Jie Xu, Zhaoning Wang, Kai Zhang, Bojing Jia, Xiaomeng Hou, Bin Li, Samantha Kuan, Zihan Wang, Jingbo Shang, Allen Wang and Sebastian Preissl at UC San Diego, Hanqing Liu, Jingtian Zhou, Antonio Pinto-Duarte, Jacinta Lucero, Julia Osteen, Michael Nunn, and M. Margarita Behrens at the Salk Institute for Biological Studies, and Kimberly A. Smith, Bosiljka Tasic, Zizhen Yao and Hongkui Zeng at the Allen Institute for Brain Science.

The first study was supported, in part, by the NIH BRAIN Initiative (grants U19MH114831 and U19MH114830).

13 December 2023, Nature.
DOI: 10.1038/s41586-023-06819-6

Co-authors of the second study include: Nathan R. Zemke, Ethan J Armand, Seoyeon Lee, Jingtian Zhou, Yang Eric Li, Daofeng Li, Xiaoyu Zhuo, Vincent Xu and Michael Miller at UC San Diego, Wenliang Wang Hanqing Liu, Wei Tian, Joseph R. Nery, Rosa G Castanon, Anna Bartlett, Julia K. Osteen, Edward M. Callaway, Margarita Behrens and Joseph R. Ecker at the Salk Institute for Biological Studies, Daofeng Li, Xiaoyu Zhuo, Vincent Xu and Ting Wang at Washington University School of Medicine, Fenna M. Krienen at Princeton University, Qiangge Zhang and Guoping Feng at The Broad Institute of MIT and Harvard, Naz Taskin, Jonathan Ting and Ed S. Lein at the Allen Institute for Brain Science and Steven A. McCarroll at Harvard Medical School.

The second study was supported, in part, by the NIH BRAIN Initiative (grants U19MH11483, U19MH114831-04s1, 5U01MH121282, and UM1HG011585).

The post Decoding Humanity: How Mapping the Mouse Brain Unveils Human Secrets appeared first on Tekh Decoded.

Lead Image: A Harvard Medical School study found a sharp increase in U.S. youth visiting emergency departments for mental health crises during COVID-19’s second year. The study highlights the urgent need for improved mental health resources and policies, especially as adolescent girls face a higher risk of severe mental health issues like self-harm and suicide attempts.

A surge in girls’ visits drove the trend, fueling longer waits for inpatient care.

During the second year of the COVID-19 pandemic, there was a significant rise in the number of young Americans seeking emergency hospital care for mental health crises. This was revealed in a study by researchers at the Department of Health Care Policy, Blavatnik Institute, Harvard Medical School, and published in JAMA Psychiatry.

Rising Mental Health Emergencies Among Youth

Amid escalating concerns over a youth mental health crisis, these results offer critical insights into acute medical service use by young people facing mental health issues like self-harm and suicide attempts.

The findings, the researchers said, highlight the critical need for policies to increase resources for mental health for all aspects of care, including emergency departments, inpatient pediatric mental health facilities, primary care, and prevention.

“The bottom line is that as a society, we need to do more to protect the mental health and wellbeing of our young people,” said Haiden Huskamp, Henry J. Kaiser Professor of Health Care Policy at HMS.

Pandemic Aggravates Existing Mental Health Issues

Numerous reports have noted that the stress and isolation of the COVID-19 pandemic have exacerbated what US Surgeon General Vivek Murthy has described as a crisis of adolescent mental health.

And the trend is not new, as numerous studies have shown. The suicide rate among young people increased by 57 percent in the decade before the pandemic, compared with the preceding decade. With increasing prevalence of mental illness among youth and a chronic lack of providers, the mental health care system has been stressed for a long time, the researchers said.

The pandemic helped bring those festering problems to a head, the authors said. The multiple and compounding stressors of COVID-19 have taken a grave toll on the mental health of a whole generation of young people and are taxing a mental health care system that’s already stretched to capacity, they said.

“One of the most concerning findings was the dramatic increase in the number of adolescents waiting multiple days in the emergency room before being admitted to facilities that can provide the level of treatment they need,” said Huskamp.

Alarming Trends in Adolescent Mental Health Services

For their analysis, the researchers looked at private health insurance claims submitted between March 2019 and February 2022 for more than 4 million people between the ages of 5 and 17. The researchers compared numbers and outcomes of emergency department visits related to mental health conditions from the year before the COVID-19 pandemic (March 2019 to February 2020) with data from the second year of the pandemic (March 2021 to February 2022).

The young people in the study sample were 7 percent more likely to have had an ED visit for mental health in the second year of the pandemic than they were in the 12 months prior to the pandemic. The overall increase was driven by a dramatic surge in emergency department visits among adolescent girls, who were 22 percent more likely to have an emergency room visit during the second year of the pandemic compared with the year before the virus hit.

“One surprising and concerning finding was that the increase in ED visits was largely driven by girls who came to the hospital for conditions such as suicidal thoughts or plans, suicide attempts, and self-harm,” first author Lindsay Overhage, an HMS MD/PhD student with an interest in mental health policy, said. “It’s critical that we do all we can to prevent these serious illnesses and to treat those who are suffering.”

Overall, the likelihood that a child who visited the ED for mental health care would be admitted to an inpatient mental health program increased by 8 percent in the second year of the pandemic, relative to the year before the outbreak. The number of young people who spent at least two days waiting to be admitted from the ED to an inpatient psychiatric service increased by 76 percent.

Critical Approaches to Addressing the Youth Mental Health Crisis

The findings underscore an urgent need to identify and relieve the underlying stresses that are driving this steep rise in depression, anxiety, self-harm, and other serious mental health problems among young people in an effort to prevent suffering, the researchers said. These efforts, they added, must include research to help understand why girls have been affected worse than boys.

The study also highlights the importance of working rapidly to increase inpatient and outpatient child psychiatry capacity to give young people in crisis the care that they need and to reduce the strain on the acute mental health care system, the researchers said. The researchers point to a variety of ways to address this problem including improving inpatient capacity, increasing the availability of mental health providers, preventing and fighting burnout among mental health care providers, and supporting non-specialist primary care and emergency care clinicians who provide mental health care.

Promising Treatments

For children in crisis now, the researchers note that there are promising treatments that can be delivered in emergency departments, in person, or using telemedicine. These therapies may reduce the need for hospital admissions or at least allow patients to begin some effective treatment while they are waiting for a spot in an inpatient program.

Reference: “Trends in Acute Care Use for Mental Health Conditions Among Youth During the COVID-19 Pandemic” by Lindsay Overhage, Ruth Hailu, Alisa B. Busch, Ateev Mehrotra, Kenneth A. Michelson, Haiden A. Huskamp, 12 July 2023, JAMA Psychiatry.
DOI: 10.1001/jamapsychiatry.2023.2195

Additional authors included Ruth Hailu, Alisa B. Busch, Ateev Mehrotra, and Kenneth Michelson of HMS.

The study was supported by the National Institute of Mental Health (R01 MH112829 and T32 MH019733), Agency for Healthcare Research and Quality (K08HS026503), and the National Institute of Aging (T32AG51108).

The post HomeHealth News Spike in Child Mental Health Emergencies During Second Year of COVID Pandemic appeared first on Tekh Decoded.

Lead Image: The NexGen 7T MRI scanner marks a breakthrough in brain imaging, providing unprecedented resolution that could transform neuroscience research and the diagnosis of brain disorders. Funded by the BRAIN Initiative, this technology enables detailed imaging of brain circuitry and could lead to significant advancements in understanding mental and neurological disorders.

Higher resolution will allow neuroscientists to more precisely localize and trace brain networks.

An intense international effort to improve the resolution of magnetic resonance imaging (MRI) for studying the human brain has culminated in an ultra-high resolution 7 Tesla scanner that records up to 10 times more detail than current 7T scanners and over 50 times more detail than current 3T scanners, the mainstay of most hospitals.

Enhanced Detail in Brain Imaging

The dramatically improved resolution means that scientists can see functional MRI (fMRI) features 0.4 millimeters across, compared to the 2 or 3 millimeters typical of today’s standard 3T fMRIs.

“The NexGen 7T scanner is a new tool that allows us to look at the brain circuitry underlying different diseases of the brain with higher spatial resolution in fMRI, diffusion and structural imaging, and therefore to perform human neuroscience research at higher granularity. This puts UC Berkeley at the forefront of human neuroimaging research,” said David Feinberg, the director of the project to build the scanner, acting professor at the Helen Wills Neuroscience Institute at the University of California, Berkeley, and president of Advanced MRI Technologies (AMRIT), a research company based in Sebastopol, California.

“The ultra-high resolution scanner will allow research on underlying changes in brain circuitry in a multitude of brain disorders, including degenerative diseases, schizophrenia and developmental disorders, including autism spectrum disorder.”

This next generation or NexGen 7T MRI scanner is described in a paper that will be published today (November 27) in the journal Nature Methods.

A New Era in Neuroscience Research

The improved resolution will help neuroscientists probe the neuronal circuits in different regions of the brain’s neocortex and allow researchers to track signals propagating from one area of the cortex to another as we think and reason, and perhaps discover underlying causes of developmental disorders. This could lead to better ways of diagnosing brain disorders, perhaps by identifying new biomarkers that would allow diagnosis of mental disorders earlier or, more specifically, in order to choose the best therapy.

“Normally, MRI is not fast enough at all to see the direction of the information being passed from one area of the brain to another,” Feinberg said. “The scanner’s higher spatial resolution can identify activity at different depths in the brain’s cortex to indirectly reveal brain circuitry by differentiating activity in different cell layers of the cortex.”

This is possible because neuroscientists have found in vision brain areas that the superficial and deepest cortex layers (blue arrows in image on right) incorporate “top-down” circuits, that is, they receive information from higher cortical brain areas, whereas the middle cortex involves “bottom-up” circuitry, receiving input to the brain from our senses. Pinpointing the fMRI activity to a specific depth in the cortex lets neuroscientists track the flow of information throughout the brain and cortex.

With the higher spatial resolution, neuroscientists will be able to home in on the activity of something on the order of 850 individual neurons within a single voxel — a 3D pixel — instead of the 600,000 recorded with standard hospital MRIs, said Silvia Bunge, a UC Berkeley professor of psychology who is one of the first to use the NexGen 7T to conduct research on a human brain.

“We were able to look at the layer profile of the prefrontal cortex, and it’s beautiful,” said Bunge, who studies abstract reasoning. “It’s so exciting to have this state-of-the-art, world-class machine.”

Revolutionizing Brain Disorder Research

For William Jagust, a UC Berkeley professor of public health who studies the brain changes associated with Alzheimer’s disease, the improved resolution could finally help connect the dots between observed changes due to Alzheimer’s that occur in the brain — abnormal clumps of protein called beta amyloid and tau — and changes in memory.

“We know that part of the memory system in the brain degenerates as we get older, but we know little about the actual changes to the memory system — we can only go so far because of the resolution of our current MRI systems,” said Jagust. “With this new scanner, we think we’re going to be able to take apart a lot more carefully exactly where things have gone wrong. This could help with diagnosis or predicting outcomes in normal people.”

Jack Gallant, a UC Berkeley professor of psychology, hopes the scanner will help neuroscientists discover how functional changes in the brain lead to developmental and mental disorders such as dyslexia, autism and schizophrenia, or that result from neurological disorders, such as dementia and stroke.

“Mental disorders have an enormous impact on individuals, families and society. Together they represent about 10% of the U.S. GDP. Mental disorders are fundamentally disorders of brain function, but functional measures are not used currently to diagnose most brain disorders or to look to see if a treatment’s working. Instead, these disorders are diagnosed behaviorally. This is a weak approach, because there are a lot of different mental brain states that can lead to exactly the same behavior,” Gallant said. “What we need is more powerful MRI machines like this so that we can map, at high resolution, how information is represented in the brain. To me this is the big potential clinical benefit of ultra-high resolution MRI.”

BRAIN Initiative

The breakthrough came about through an initial $13.4 million in funding from the Brain Research through Advancing Innovative Neurotechnologies (BRAIN) Initiative of the U.S. National Institutes of Health (NIH). The initiative aims to develop new technologies that will produce a dynamic picture of the brain showing how individual cells and complex neural circuits interact across the brain and over time.

Additional funding from UC Berkeley’s Chancellor’s Office and the Weill Neurohub brought the total funding to over $22 million, which allowed Feinberg to assemble a multidisciplinary team of academics and leading scientists at the multinational corporation Siemens Healtheneers, a major manufacturer of hospital and research MRI scanners; MR CoilTech Limited of Glasgow, Scotland, maker of transmitter and receiver detector coils used in MRI to generate and record signals; and AMRIT, a designer of imaging pulse sequences that control the scanner hardware.

Incorporating newly developed hardware technology from those groups, Siemens collaborated with Feinberg’s team to rebuild a conventional 7 Tesla MRI scanner delivered to UC Berkeley in 2000 to improve the spatial resolution in pictures captured during brain scans.

“There’s been a large increase throughout the world of sites that use 7T MRI scanners, but they were mostly for development and were difficult to use,” said Nicolas Boulant, a physicist visiting from the NeuroSpin project at the University of Paris in Saclay, where he leads the team that operates the world’s only 11.7 Tesla MRI scanner, the strongest magnetic field employed to date. “David’s team really put together many ingredients to make a quantum leap at 7 Tesla, to go beyond what was achievable before and gain performance.”

Boulant hopes to adapt some of the new ingredients in the NexGen 7T — in particular, redesigned gradient coils — to eventually achieve even better resolution with the 11.7 Tesla MRI scanner. The gradient coils generate a rising magnetic field across the brain so that each part of the brain sees a different field strength, which helps to precisely map brain activity.

“The higher the magnetic field, the more difficult it is to really grab the potential promised by these higher-field MRI scanners to see finer details in the human brain,” he said. “You need all this peripheral equipment, which needs to be on steroids to meet those promises. The NexGen 7T is really a game-changer when you want to do neuro MRI.”

Innovative Technology

To reach higher spatial resolution, the NexGen 7T scanner had to be designed with a greatly improved gradient coil and with larger receiver array coils — which detect the brain signals — using from 64 to 128 channels to achieve a higher signal-to-noise ratio (SNR) in the cortex and faster data acquisition. All these improvements were combined with a higher signal from the ultra-high field 7T magnet to achieve cumulative gains in the scanner performance.

The extremely powerful gradient coil is the first to be made with three layers of wire windings. Designed by Peter Dietz at Siemens in Erlangen, Germany, the “Impulse” gradient has 10 times the performance of gradient systems in current 7T scanners. Mathias Davids, then a physics graduate student at Heidelberg University in Mannheim, Germany, and a member of Feinberg’s team, collaborated with Dietz in performing physiologic modeling to allow a faster gradient slew rate — a measure of how quickly the magnetic field changes across the brain — while remaining under the neuronal stimulation thresholds of the human body.

“It’s designed so that the gradient pulses can be turned on and off much quicker — in microseconds — to record the signals much quicker, and also so the much higher amplitude gradients can be utilized without stimulating the peripheral nerves in the body or stimulating the heart, which are physiologic limitations,” Feinberg said.

A second key development in the scanner, Feinberg said, is the 128-channel receiver system that replaces the standard 32 channels. The large receiver coil arrays built by Shajan Gunamony of MR CoilTech in Glasgow, UK, gave a higher signal-to-noise ratio in the cerebral cortex and also provided higher parallel imaging acceleration for faster data acquisition to encode large image matrices for ultra high resolution fMRI and structural MRI.

To take advantage of the new hardware technology, Suhyung Park, Rüdiger Stirnberg, Renzo Huber, Xiaozhi Cao and Feinberg designed new pulse sequences of precisely timed gradient pulses to rapidly achieve ultra high resolution. The smaller voxels, measured in units of cubic millimeters and less than 0.1 microliter, provide a 3D image resolution that is 10 times higher than that of previous 7T fMRIs and 125 times higher than the typical hospital 3T MRI scanners used for medical diagnosis.

Voxels Matter

The most common MRI scanners employ superconducting magnets that produce a steady magnetic field of 3 Tesla — 90,000 times stronger than Earth’s magnetic field.

“A 3T fMRI scanner can resolve spatial details with a resolution of about 2 to 3 mm. The cortical circuits that underpin thought and behavior are about 0.5 mm across, so standard research scanners cannot resolve these important structures,” Gallant said.

In contrast, fMRI focuses on blood flow in arteries and veins and can vividly distinguish oxygenated hemoglobin funneling into working areas of the brain from deoxygenated hemoglobin in less active areas. This allows neuroscientists to determine which areas of the brain are engaged during a specific task.

But again, the 3 mm resolution of a 3T fMRI can distinguish only large veins, not the small ones that could indicate activity within microcircuits.

The NexGen 7T will allow neuroscientists to pinpoint activity within the thin cortical layers in the gray matter, as well as within the narrow column circuits that are organized perpendicular to the layers. These columns are of special interest to Gallant, who studies how the world we see is represented in the visual cortex. He has actually been able to reconstruct what a person is seeing based solely on recordings from the brain’s visual cortex.

“The machine that David has built, in theory, should get down to 500 microns, or something like that, which is way better than anything else — we’re very near the scale you would want if you’re getting signals from a single column, for example,” Gallant said. “It’s fantastic. The whole thing about MRI is how big is the little volumetric unit, the voxel, the three-dimensional pixel that you’re recording from. That’s the only thing that matters.”

For the moment, NexGen 7T brain scanners must be custom-built from regular 7T scanners. The cost should be considerably lower than the $22 million required to build the first one, however. These funds came not only from the BRAIN Initiative, but also from UC Berkeley funds through the Helen Wills Neuroscience Center, with which Feinberg, Bunge, Gallant, and Jagust are affiliated.

Feinberg said that UC Berkeley’s NexGen 7T scanner technology will be disseminated by Siemens and MR CoilTech Ltd.

“My view is that we may never be able to understand the human brain on the cellular synaptic circuitry level, where there are more connections than there are stars in the universe,” Feinberg said. ” But we are now able to see signal patterns of brain circuits and begin to tease apart feedback and feed forward circuitry in different depths of the cerebral cortex. And in that sense, we will soon be able to understand the human brain organization better, which will give us a new view into disease processes and ultimately allow us to test new therapies. We are seeking a better understanding and view of brain function that we can reliably test and reproducibly use noninvasively.”

Reference: “Next-generation MRI scanner designed for ultra-high-resolution human brain imaging at 7 Tesla” 27 November 2023, Nature Methods.
DOI: 10.1038/s41592-023-02068-7

Other co-authors of the paper are Alexander Beckett of Advanced MRI Technologies; Chunlei Liu of UC Berkeley’s Helen Wills Neuroscience Institute; An (Joseph) Vu of UC San Francisco; Lawrence Wald, Bernhard Gruber, Jon Polimeni and Jason Stockmann of the A. A. Martinos Center for Biomedical Imaging at Massachusetts General Hospital; Kawin Setsompop of Stanford University in California; Rudiger Sternberg of the German Center for Neurodegenerative Diseases in Bonn, Germany; Laurentius (Renzo) Huber of Maastricht University in the Netherlands; and Suhyung Park at Chonnam National University, South Korea.

The work was supported by BRAIN Initiative grants through the NIH (U01-EB025162, R01-322 MH111444) and other NIH grants (P41-EB030006, NIH R44-MH129278), as well as by funds from UC Berkeley’s Chancellor’s Office and the Weill Neurohub.

The post Brain Imaging Redefined: NexGen 7T MRI Achieves 10x Better Resolution appeared first on Tekh Decoded.