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Can Exercise Truly Reverse Aging? New Research Shows Reduction in Age-Related Fat

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Glowing Human Strength Longevity

Researchers have discovered that certain fats accumulate in tissues with age but can be reduced through regular exercise. This finding, which sheds new light on the biological processes of aging, was derived from studies conducted on both mice and humans, emphasizing the potential for new aging interventions.

Scientists have found that a specific kind of fat builds up in tissues as they age, and that exercise can reverse this process. A team from Amsterdam UMC, in collaboration with researchers from Maastricht UMC+, studied tissue from both mice and humans before and after exercise to reach this conclusion.

The results were recently published in the journal Nature Aging.

“The idea that we could reverse aging is something that was long considered science fiction, but these findings do allow us to understand a lot more about the aging process,” says Riekelt Houtkooper, Professor at the laboratory Genetic Metabolic Diseases of Amsterdam UMC. “Everyone says that ‘it’s just part of getting older,’ but this doesn’t actually have to be true. By understanding more about the aging process, we can also look into new ways of intervening,” says Georges Janssens, first author of the paper and assistant professor at Amsterdam UMC.

Research on Age-Related Diseases

In recent years, laboratory research has shown that we may be able to counteract age-related diseases by intervening in the fundamental processes that lead to aging. Although science has increasingly mapped out how metabolism changes during aging, large parts remained uncharted. “We wanted to add a new chapter to the atlas. Lipids are an important part of our diet, and crucial for the functioning of our body cells. Specific lipids make up the membrane of cells, which ensures that the inside and outside remain separate,” says Houtkooper.

In order to add this new chapter, the research team investigated how the composition of fats changes in mice. They looked at ten different tissues, including muscles, kidneys, liver, and heart. It was noticed that one type of lipid, the bis(monoacylglycero)phosphates (or BMPs), were elevated in all tissues from the older animals. Suggesting an accumulation of these lipids during aging. They then investigated whether this also happens in humans. Although it was not possible to obtain as many different tissues, the accumulation of BMP was also visible in muscle biopsies of older people. Finally, they then completed more muscle biopsies from people before and after a healthy intervention that included one hour of exercise a day and saw the level of BMPs decreased in the active participants.

“These results are an important new step for our understanding of the aging process, but they are certainly not the final answer. We plan to conduct follow-up studies to better understand how BMPs contribute to aging, what are the consequences of BMP accumulation on the aging process, and whether this can only be influenced by exercise or are the other ways to affect BMPs levels,” concludes Houtkooper.

Reference: “A conserved complex lipid signature marks human muscle aging and responds to short-term exercise” by Georges E. Janssens, Marte Molenaars, Katharina Herzog, Lotte Grevendonk, Carlijn M. E. Remie, Martin A. T. Vervaart, Hyung L. Elfrink, Eric J. M. Wever, Bauke V. Schomakers, Simone W. Denis, Hans R. Waterham, Mia L. Pras-Raves, Michel van Weeghel, Antoine H. C. van Kampen, Alessandra Tammaro, Loes M. Butter, Sanne van der Rijt, Sandrine Florquin, Aldo Jongejan, Perry D. Moerland, Joris Hoeks, Patrick Schrauwen, Frédéric M. Vaz and Riekelt H. Houtkooper, 12 April 2024, Nature Aging.
DOI: 10.1038/s43587-024-00595-2

New Holographic Technique Breaks Computational Barriers

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Medical Imaging Hologram Technology

A new method developed by researchers significantly simplifies the creation of computer-generated holograms, allowing for real-time generation of 3D images with accurate depth. This breakthrough could revolutionize holographic display technology across various industries.

A groundbreaking approach utilizes a split Lohmann lens-based diffraction model for the real-time creation of Computer-Generated Holography (CGH), dramatically lowering computational demands while preserving the quality of 3D visualizations.

Holographic displays present an exciting pathway toward producing realistic 3D images that give the illusion of continuous depth, promising transformative impacts in areas like entertainment, medical imaging, and virtual reality. Yet, traditional approaches to creating computer-generated holograms (CGHs) are hampered by the need for repetitive calculations, resulting in high computational demands and making them unsuitable for real-time applications.

To tackle this issue, researchers from the University of Shanghai for Science and Technology (China) have introduced a novel method for CGH generation that significantly reduces computational overhead while maintaining high-quality 3D visualization. As reported in Advanced Photonics Nexus, their approach leverages a split Lohmann lens-based diffraction model, enabling rapid synthesis of 3D holograms through a single-step backward propagation calculation.

By incorporating a specially designed virtual digital phase modulation into the split Lohmann lens, their method achieves highly accurate reconstruction of 3D scenes with precise depth perception.

Full Color Holographic Near Eye Display Employs an Eyepiece Lens To Magnify 3D Images

Full-color holographic near-eye display employs an eyepiece lens to magnify 3D images, which are then recorded by adjusting the focus of the camera lens. A fast hologram is then generated using a Split-Lohmann lens-based diffraction algorithm. Credit: Chang et al., doi 10.1117/1.APN.3.3.036001

Revolutionizing Holographic Display Creation

The significance of this research lies in its potential to revolutionize the creation of holographic displays by offering a practical solution for real-time CGH generation. Unlike traditional methods that suffer from computational bottlenecks, the proposed approach ensures consistent computation speed regardless of the depth sampling density, thereby enabling seamless integration into various applications requiring immersive 3D visualization.

To validate the effectiveness of their method, the researchers conducted both simulations and experiments, demonstrating its ability to generate realistic 3D holographic displays with accurate depth perception.

Overall, the study presents a promising advancement in the field of computer-generated holography, offering a practical solution for creating immersive 3D visualizations without the computational limitations of traditional methods. It helps pave the way for the widespread adoption of holographic displays in diverse industries and applications.

Reference: “Split Lohmann computer holography: fast generation of 3D hologram in single-step diffraction calculation” by Chenliang Chang, Xian Ding, Di Wang, Zhizhou Ren, Bo Dai, Qi Wang, Songlin Zhuang and Dawei Zhang, 28 March 2024, Advanced Photonics Nexus.
DOI: 10.1117/1.APN.3.3.036001

Brain Synchrony in Family Dynamics

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Parents Child Brain Art Concept

A study found that mothers with insecure attachments have heightened brain-to-brain synchrony with their children, suggesting a compensatory mechanism for relationship challenges. Credit: SciTechDaily.com

More synchrony between parents and children may not always be better, new research has revealed.

For the first time a new University of Essex study looked at behavioural and brain-to-brain synchrony in 140 families with a special focus on attachment.

It looked at how they feel and think about emotional bonds whilst measuring brain activity as mums and dads solved puzzles with their kids.

The study – published in the journal Developmental Science – discovered that mums with insecure attachment traits showed more brain-to-brain synchrony with their children.

Importance of Attachment

Dr. Pascal Vrticka, from the Department of Psychology, said: “For secure child attachment development, sensitive and mutually attuned interactions with parents are crucial.

“If the parent, here the mother, has more insecure attachment traits it may be more difficult for the dyad to achieve optimal behavioral synchrony.

“Increased brain-to-brain synchrony may reflect a neural compensation mechanism to overcome otherwise less attuned interaction elements.”

The study also discovered different behavioral and brain-to-brain synchrony patterns depending on whether the parent was a mum or a dad.

Gender Differences in Synchrony

Fathers and children showed stronger brain-to-brain synchrony, whereas mums and their kids had stronger behavioral synchrony.

These findings suggest higher father-child brain-to-brain synchrony may reflect a neural compensation strategy to counteract a relative lack of behavioral synchrony.

It hopes this research will springboard studies into parent-child relationships and open up new avenues for intervention and prevention.

Future Research and Applications

It comes as Dr. Vrticka prepares to work with the NHS to explore family relationships.

He added: “Together with the East Suffolk and North Essex NHS Foundation Trust, we will soon start looking at synchrony within families with neurodivergent children and children with experiences of care and adoption.

“Our aim is to find behavioral and neurobiological correlates of an optimal range of synchrony to help all families with their relationships and child attachment development.

“In doing so, we must appreciate that not only low but also high synchrony can signal interaction and relationship difficulties.”

Methodology of the Study

Attachment was assessed in parents with an interview and in children with a story completion task.

Brain-to-brain synchrony between parents and children was studied with functional near-infrared spectroscopy (fNIRS) hyper scanning.

Finally, the parent-child interaction was video-recorded and coded for behavioral synchrony.

Reference: “Visualizing the invisible tie: Linking parent–child neural synchrony to parents’ and children’s attachment representations” by Trinh Nguyen, Melanie T. Kungl, Stefanie Hoehl, Lars O. White and Pascal Vrtička, 24 March 2024, Developmental Science.
DOI: 10.1111/desc.13504

The study was led by Dr. Trinh Nguyen who now works at the Italian Institute of Technology in Rome, Italy, and Dr. Melanie Kungl from the University of Erlangen-Nuremberg, Germany – along with colleagues from Vienna, Berlin, and Leipzig.

The Chaotic Birth of Brown Dwarfs Revealed

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Forming Brown Dwarf Art Concept

New observations reveal that brown dwarfs may form through dynamic processes similar to larger stars, featuring collisions and magnetic influences in their early development stages. (Artist’s concept.) Credit: SciTechDaily.com

New observations provide insights into whether the birth of the giant planets takes a similar course to that of stars.

The birth of stars is a chaotic and dynamic process, especially in the early phase, which is characterized by complex gas structures in the form of spirals and streamers. Such structures are termed “feeding filaments” because they feed the gaseous material from the surroundings to the newly born star, akin to cosmic umbilical cords.

Cosmic Umbilical Cord

Brown dwarfs are celestial objects with masses less than one-tenth of the mass of the Sun. This makes them too small to undergo nuclear fusion and shine like stars. Before now, scientists did not know whether brown dwarfs form like sun-like stars or not. A test of this hypothesis requires high-sensitivity and high-angular resolution observations of brown dwarfs during their earliest formation stages. An international team led by LMU astrophysicist Dr. Basmah Riaz from the University Observatory Munich has now accomplished just that: The researchers conducted observations of the extremely young brown dwarf, Ser-emb 16, using the highly sophisticated ALMA observatory in Chile and recently published their results in the journal Monthly Notices of the Royal Astronomical Society.

Brown Dwarf Ser-emb ALMA

ALMA observations of the spiral (left) and the tail (right) towards the extremely young brown dwarf Ser-emb 16. Credit: Basmah Riaz

“Our observations have revealed spectacular large-scale spiral and streamer structures that have never been seen before towards a newly born brown dwarf,” says Riaz. The filaments cover a vast area of about 2,000-3,000 astronomical units and are connected to Ser-emb 16. Clumps of matter were also seen around it, which themselves could potentially evolve into young brown dwarfs. “These observations show, for the first time, the influence of the external environment, which results in asymmetric mass accretion via feeding filaments on to a brown dwarf in the making,” says the astronomer.

Collapsing Clumps or Magnetic Cores?

The spiral structures and streamers provide important clues about how brown dwarfs form. Having simulated possible scenarios, the researchers compared them with data from the ALMA observatory. The large structures could be explained, for example, by collisions of collapsing clumps within a star-forming region. For this to occur, such collisions would have to happen at least once during the lifetime of star-forming cores. “We have shown through new numerical simulations that collisions trigger the collapse of even small clumps to form brown dwarfs. Spirals and streamers of various sizes and morphologies form due to the collisions happening sideways, not head-on,” says co-author Dr. Dimitris Stamatellos from the University of Central Lancashire in England. If this model is correct, it implies a dynamic brown dwarf formation process, similar to Sun-like stars, where chaotic interactions in a star-forming environment are common from an early age.

In another scenario, the simulations showed that the observed structures correspond to the large (pseudo)-disk around a very young brown dwarf, where the (pseudo)-disk has been twisted by the rotation of the brown dwarf core in the presence of a strong magnetic field. If this model is correct, it means the magnetic field plays an important role in the brown dwarf formation process.

“Our ALMA observations provide a unique insight into the early formation stages of brown dwarfs,” says Riaz. A comparison of the observations with the models supports a gravitational infall scenario which can explain the asymmetric mass accretion seen in the shape of spirals and streamers, as seen around forming stars. “Consequently, Ser-emb 16 constitutes a unique case of a brown dwarf caught in the process of forming in a star-like fashion,” explains Professor Masahiro Machida from Kyushu University in Japan, also co-author of the study.

Reference: “Observations of spiral and streamer on a candidate proto-brown dwarf” by B Riaz, D Stamatellos and M N Machida, 11 March 2024, Monthly Notices of the Royal Astronomical Society.
DOI: 10.1093/mnras/stae724

A Super Cosmic Ray Accelerator – Chinese Astronomers Discover Giant Ultra-High-Energy Gamma-Ray Bubble

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Giant Ultra High Energy Gamma Ray Bubble Structure

LHAASO has identified a super cosmic ray accelerator in a gamma-ray bubble in the Cygnus region, marking a significant advancement in understanding cosmic rays with energies exceeding 10 PeV and their origins within the Milky Way. Rendering of a giant ultra-high-energy gamma-ray bubble structure. Credit: China Media Group

The Large High Altitude Air Shower Observatory (LHAASO) has discovered a giant ultra-high-energy gamma-ray bubble structure in the Cygnus star-forming region, which is the first time that the origin of cosmic rays with energy higher than 10 Peta-Electronvolt (PeV, 1PeV=1015eV) has been discovered.

This achievement was published in the form of a cover article in Science Bulletin on February 26.

The research was completed by the LHAASO Collaboration led by Prof. Cao Zhen as the spokesperson from the Institute of High Energy Physics of the Chinese Academy of Sciences. Dr. Gao Chuandong, Dr. Li Cong, Prof. Liu Ruoyu, and Prof. Yang Ruizhi are the co-corresponding authors of the paper.

Cosmic rays are charged particles from outer space, mainly composed of protons. The origin of cosmic rays is one of the most important frontier issues in modern astrophysics. Measurements of cosmic rays in past decades have revealed a break around 1 PeV in the energy spectrum (i.e., the distribution of cosmic ray abundance as a function of the particle energy), which is called the “knee” of the cosmic ray energy spectrum due to its shape resembling a knee joint.

Ultra High Energy Cosmic Rays Propagation in Interstellar Space

Rendering of ultra-high-energy cosmic rays propagation in interstellar space. Credit: China Media Group

Scientists believe that cosmic rays with energy lower than the “knee” originate from astrophysical objects within the Milky Way, and the existence of the “knee” also indicates that the energy limit for accelerating protons from most of the cosmic ray sources in the Milky Way is around a few PeV. However, the origin of cosmic rays in the “knee” region is still an unsolved mystery and one of the most intriguing topics in cosmic ray research in recent years.

Discovery of a Super Cosmic Ray Accelerator

LHAASO has discovered a giant ultra-high-energy gamma-ray bubble structure in the Cygnus star-forming region, with multiple photons exceeding 1 PeV inside the structure, with the highest energy reaching 2.5 PeV, indicating the presence of a super cosmic ray accelerator inside the bubble, which continuously accelerates high-energy cosmic ray particles with energies of up to 20 PeV and injects them into interstellar space. These high-energy cosmic rays collide with interstellar gas and produce gamma rays. The intensity of these gamma-ray photons is clearly correlated with the distribution of the surrounding gas, and the massive star cluster (the OB association, Cygnus OB2) near the center of the bubble is the most promising candidate for the super cosmic ray accelerator. Cygnus OB2 is composed of many young, hot, massive stars with surface temperatures exceeding about 35,000 °C (O-type stars) and 15,000 °C (B-type stars).

Large High Altitude Air Shower Observatory in Daocheng County

The Large High Altitude Air Shower Observatory in Daocheng County, southwest China’s Sichuan Province. Credit: China Media Group

The radiation luminosity of these stars is hundreds to millions of times that of the Sun, and the huge radiation pressure blows away the surface material of the stars, forming dynamic stellar winds with speeds up to thousands of kilometers per second. The collision of stellar winds with the surrounding interstellar medium and the violent collision between stellar winds have created ideal sites for efficient particle acceleration. This is the first super cosmic ray accelerator identified as of now. With increasing observation time, LHAASO is expected to detect more super cosmic ray accelerators, and hopefully solve the mystery of the origin of cosmic rays in the Milky Way.

LHAASO’s observation has also indicated that the super cosmic ray accelerator inside the bubble significantly increases the cosmic ray density in the surrounding interstellar space, far exceeding the average level of cosmic rays in the Milky Way. The spatial extension of the density excess even exceeds the observed range of bubbles, providing a possible explanation for the excess of diffuse gamma-ray emission from the Galactic Plane previously detected by LHAASO.

Prof. Elena Amato, a renowned astrophysicist from the Italian National Institute for Astrophysical (INAF), highlighted the impact of the discovery on the origin of Cosmic Rays in general. She also commented that these results “not only impacts our understanding of diffuse emission, but has also very relevant consequences on our description of cosmic ray (CR) transport in the Galaxy.”

Reference: “An ultrahigh-energy γ-ray bubble powered by a super PeVatron” by LHAASO Collaboration, 23 December 2023, Science Bulletin.
DOI: 10.1016/j.scib.2023.12.040

Quantum Leap in Window Technology Delivers Dramatic Energy Savings

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New Transparent Window Coating Blocks Heat

Researchers at the University of Notre Dame have developed a new window coating to block heat-generating ultraviolet and infrared light and allow for visible light, regardless of the sun’s angle. Credit: University of Notre Dame

A new window coating reduces indoor temperatures and energy costs by selectively blocking heat-producing light, effective at any sunlight angle.

Windows welcome light into interior spaces, but they also bring in unwanted heat. A new window coating blocks heat-generating ultraviolet and infrared light and lets through visible light, regardless of the sun’s angle. The coating can be incorporated onto existing windows or automobiles and can reduce air-conditioning cooling costs by more than one-third in hot climates.

Efficient Design for Changing Sun Angles

“The angle between the sunshine and your window is always changing,” said Tengfei Luo, the Dorini Family Professor for Energy Studies at the University of Notre Dame and the lead of the study. “Our coating maintains functionality and efficiency whatever the sun’s position in the sky.”

Window coatings used in many recent studies are optimized for light that enters a room at a 90-degree angle. Yet at noon, often the hottest time of the day, the sun’s rays enter vertically installed windows at oblique angles.

Advanced Materials and Techniques

Luo and his postdoctoral associate Seongmin Kim previously fabricated a transparent window coating by stacking ultra-thin layers of silica, alumina, and titanium oxide on a glass base. A micrometer-thick silicon polymer was added to enhance the structure’s cooling power by reflecting thermal radiation through the atmospheric window and into outer space.

Additional optimization of the order of the layers was necessary to ensure the coating would accommodate multiple angles of solar light. However, a trial-and-error approach was not practical, given the immense number of possible combinations, Luo said.

To shuffle the layers into an optimal configuration — one that maximized the transmission of visible light while minimizing the passage of heat-producing wavelengths — the team used quantum computing, or more specifically, quantum annealing, and validated their results experimentally.

Results and Applications

Their model produced a coating that both maintained transparency and reduced temperature by 5.4 to 7.2 degrees Celsius (9.7 to 13 degrees Fahrenheit) in a model room, even when light was transmitted in a broad range of angles. The lab’s results were recently published in Cell Reports Physical Science.

“Like polarized sunglasses, our coating lessens the intensity of incoming light, but, unlike sunglasses, our coating remains clear and effective even when you tilt it at different angles,” Luo said.

The active learning and quantum computing scheme developed to create this coating can be used to design a broad range of materials with complex properties.

Reference: “Wide-angle spectral filter for energy-saving windows designed by quantum annealing-enhanced active learning” by Seongmin Kim, Serang Jung, Alexandria Bobbitt, Eungkyu Lee and Tengfei Luo, 4 March 2024, Cell Reports Physical Science.
DOI: 10.1016/j.xcrp.2024.101847

Hidden Currents Driving Antarctica’s Rapid Melt

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Dotson Ice Shelf

New research highlights how interactions between ocean currents and the ocean floor, rather than just wind, are crucial in driving the rapid melting of Antarctic ice shelves, posing a threat to global sea levels. Dotson Ice Shelf, Amundsen Sea, Antarctica. Credit: Taewook Park

Meandering ocean currents play an important role in the melting of Antarctic ice shelves, threatening a significant rise in sea levels.

A new study published in Nature Communications has revealed that the interplay between meandering ocean currents and the ocean floor induces upwelling velocity, transporting warm water to shallower depths. This mechanism contributes substantially to the melting of ice shelves in the Amundsen Sea of West Antarctica. These ice shelves are destabilizing rapidly and contributing to sea level rise.

Led by Taewook Park and Yoshihiro Nakayama, an international team of researchers from the Korea Polar Research Institute, Hokkaido University, and Seoul National University employed advanced ocean modeling techniques to investigate the underlying forces behind the rapid melting ice shelves. In a departure from prior assumptions linking ice shelf melting primarily to winds over the Southern Ocean, this study underscores the significant role played by the interactions between meandering ocean currents and the ocean floor in driving the melting process.

The Impact on Pine Island and Thwaites Ice Shelves

The Pine Island and Thwaites ice shelves are among the fastest-changing in Antarctica and are of particular interest due to their vulnerability to warming ocean waters. They act as massive barriers restraining the glaciers behind them from flowing into the ocean. However, their rapid melting and potential collapse pose a significant threat to coastal communities worldwide because of the resulting rise in global sea levels.

The study focused on the role of a layer of warm water beneath the frigid surface waters, known as the ‘modified Circumpolar Deep Water,’ in melting these ice shelves from below. “The intensity and trajectory of ocean currents encircling the ice shelves directly govern the influx of warm water, thereby intricately shaping their rate of melting” explains Taewook. This shows the importance of the ocean in understanding and addressing the impacts of climate change.

The researchers paid attention to the ‘thermocline depth’, which is the depth of the interface between warmer deep waters and cooler surface waters. Variations in thermocline depth significantly affect the influx of warm water toward the ice shelves. Until now, it has been believed that intensified westerly winds north of the Amundsen Sea propelled ocean currents along the shelf break, carrying warmer water toward ice shelf cavities. This phenomenon is particularly pronounced during El Niño events.

“Our findings challenge conventional wisdom,” Nakayama asserts. “Our study underscores that the interplay between meandering ocean currents and the ocean floor generates upwelling velocity, bringing warm water to shallower depths. Subsequently, this warm water reaches the ice-ocean interface, accelerating ice shelf melting.” Nakayama concludes, “This internal oceanic process driving ice shelf melting introduces a novel concept. With this in mind, we have to reevaluate winds driving Antarctic ice loss, which can significantly impact future projections.”

Reference: “Amundsen Sea circulation controls bottom upwelling and Antarctic Pine Island and Thwaites ice shelf melting” by Taewook Park, Yoshihiro Nakayama and SungHyun Nam, 11 April 2024, Nature Communications.
DOI: 10.1038/s41467-024-47084-z

The study was funded by the Korea Institute of Marine Science and Technology promotion, the Korea Polar Research Institute, the Ministry of Education, Culture, Sports, Science, and Technology of Japan, and the Inoue Foundation for Science.

“Extraordinary Potential” – The New Dawn of Low-Cost, High-Efficiency Solar Cells

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Detail New Solar Panel

Researchers at Soochow University have highlighted the potential for significant advancements in solar cell efficiency, focusing on high-efficiency perovskite solar cells. Their review outlines the current state of research and future directions, emphasizing the advantages of perovskite solar cells, such as high efficiency, low cost, and flexibility.

Commercial solar panels currently have the capability to transform approximately 15% to 20% of the sunlight they capture into electrical power. However, experts at Soochow University suggest there’s significant room for improvement. They highlight that the upcoming generation of solar cells has achieved an efficiency of 26.1%, indicating potential for even higher efficiency rates. Nonetheless, they emphasize the necessity for more targeted research to not only normalize this level of efficiency but also to exceed it.

They recently published their review of the current state of research on high-efficiency perovskite solar cells and their recommendations for future work in Energy Materials and Devices.

“Metal halide perovskite solar cells are a new type of high-performance solar cell,” said first author Fengren Cao, researcher in Soochow University’s School of Physical Science and Technology. “They exhibit excellent photoelectric properties and have the potential for high efficiency and low cost, making them a promising candidate for future solar energy applications.”

Advantages of Perovskite Solar Cells

The metal halide perovskite in these solar cells is a calcium titanium oxide-like organic material that operates as a light-absorbing semiconductor to capture incidental sunlight and convert it to energy.

“Perovskite solar cells offer high efficiency, exceeding 26% in laboratory conditions; low cost, using relatively inexpensive materials and simple manufacturing processes; flexibility, as they can be made on flexible substrates — such as plastic or metal foils — enabling the development of lightweight, flexible photovoltaic devices; and they can be scaled up to larger sizes,” Cao said. “They have extraordinary potential as the next generation of photovoltaic technology.”

The Potential of Perovskite Solar Cells Graphic

Researchers at Soochow University reviewed the current developments in making perovskite solar cells more efficient and offer directions to guide future research. They currently can achieve slightly more than 25% efficiency but the research said they could achieve more if current limitations are addressed appropriately. Credit: Fengren Cao, Soochow University

However, Cao noted, only a few research teams have developed perovskite solar cells capable of 25% efficiency or more.

“Over the past years, many strategies have been adopted to improve the efficiency of perovskite solar cells,” Cao said. “But achieving more than 25% efficiency is not yet common. As such, in this paper, we summarize recent developments in high-efficiency perovskite solar cells and highlight their effective strategies in crystal regulation, interface passivation, and structural design of component layers.”

Strategies for Improving Efficiency

These strategies could effectively address the main causes of low efficiency, which are preparation process-induced defects and an unsuitable band structure, according to Cao. The band structure refers to the energy levels of electrons in the material: Too low and the cell cannot properly or efficiently convert sunlight into energy, too high and the cell faces the same issue.

Cao also noted that other types of solar cells could be combined to construct “tandem solar cells” that could work together to break the efficiency limits of a single type of solar cell. In addition, Cao said, fabrication methods for larger components need to be optimized to achieve the same efficiencies as the methods to fabricate small areas less than a 10th of a square centimeter.

“We believe that perovskite solar cells are one class of the most promising solar cells, and these efforts will ensure they can be commercialized and industrialized in the future,” Cao said, explaining that additional research would also address such challenges as tolerance to defects and issues related to stability. “The future of perovskite solar cells is incredibly exciting, and the potential for further advancements is vast.”

Reference: “Perovskite solar cells with high-efficiency exceeding 25%: A review” by Fengren Cao, Liukang Bian and Liang Li, 4 February 2024, Energy Materials and Devices.
DOI: 10.26599/EMD.2024.9370018

Other contributors include Liukang Bian and Liang Li, both with the School of Physical Science and Technology, Center for Energy Conversion Materials & Physics, Jiangsu Key Laboratory of Thin Films, Soochow University. Cao is also affiliated with Soochow University’s Jiangsu Key Laboratory of Advanced Negative Carbon Technologies.

The National Natural Science Foundation of China and the Priority Academic Program Development of Jiangsu Higher Education Institutions supported this work.

A Fish With Legs? 375-Million-Year-Old Fossil Fish Unveils Evolutionary Secrets

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Tiktaalik Reconstruction

New reconstruction of the skeleton of the 375-million-year-old fossil fish, Tiktaalik roseae. In a new study, researchers used Micro-CT to reveal vertebrae and ribs of the fish that were previously hidden beneath rock. The new reconstruction shows that the fish’s ribs likely attached to its pelvis, an innovation thought to be crucial to supporting the body and for the eventual evolution of walking. Credit: Thomas Stewart, Penn State

New findings from a fossil fish dating back 375 million years provide insights into the evolution of the axial skeleton, potentially shedding light on how our forebears transitioned from aquatic to terrestrial life.

Before the evolution of legs from fins, the axial skeleton — including the bones of the head, neck, back, and ribs — was already going through changes that would eventually help our ancestors support their bodies to walk on land. A research team including a Penn State biologist completed a new reconstruction of the skeleton of Tiktaalik, the 375-million-year-old fossil fish that is one of the closest relatives to limbed vertebrates.

The new reconstruction shows that the fish’s ribs likely attached to its pelvis, an innovation thought to be crucial to supporting the body and for the eventual evolution of walking.

A paper describing the new reconstruction, which used microcomputed tomography (micro-CT) to scan the fossil and reveal vertebrae and ribs of the fish that were previously hidden beneath rock, appeared April 2 in the journal Proceedings of the National Academy of Sciences.

“Tiktaalik was discovered in 2004, but key parts of its skeleton were unknown,” said Tom Stewart, assistant professor of biology in the Eberly College of Science at Penn State and one of the leaders of the research team. “These new high-resolution micro-CT scans show us the vertebrae and ribs of Tiktaalik and allow us to make a full reconstruction of its skeleton, which is vital to understanding how it moved through the world.”

Understanding Vertebrate Evolution

Unlike most fish, which have vertebrae and ribs that are the same along the length of the trunk, the axial skeletons of limbed vertebrates show dramatic differences in the vertebrae and ribs from the head region to the tail region. The evolution of this regionalization allowed the performance of specialized functions, one of which was a mechanical linkage between ribs in the sacral region to the pelvis that enabled support of the body by the hind limbs.

The pelvic fins of fish are evolutionarily related to hind limbs in tetrapods — four-limbed vertebrates, including humans. In fish, the pelvic fins and bones of the pelvic girdle are relatively small and float freely in the body. For the evolution of walking, the researchers explained, the hind limbs and pelvis became much larger and formed a connection to the vertebral column as a way of bracing the forces related to supporting the body.

“Tiktaalik is remarkable because it gives us glimpses into this major evolutionary transition,” Stewart said. “Across its whole skeleton, we see a combination of traits that are typical of fish and life in water as well as traits that are seen in land-dwelling animals.”

Tiktaalik: A Bridge Between Aquatic and Terrestrial Life

The original description of Tiktaalik focused on the front portion of the skeleton. Fossils were meticulously prepared to remove the surrounding matrix of rock and expose the skull, shoulder girdle and pectoral fins. The ribs in this area were large and expanded, suggesting that they may have supported the body in some way, but it was unclear exactly how they would have functioned. In 2014, the fish’s pelvis, discovered in the same location as the rest of the skeleton, was also cleaned of matrix and described.

“From past studies, we knew that the pelvis was large, and we had a sense that the hind fins were large too, but until now couldn’t say if or how the pelvis interacted with the axial skeleton,” Stewart said. “This reconstruction shows, for the first-time, how it all fits together and gives us clues about how walking might have first evolved.”

The researchers explained that, unlike our own hips where our bones fit tightly together, the connection between the pelvis and axial skeleton of Tiktaalik was likely a soft-tissue connection made of ligaments.

“Tiktaalik had specialized ribs that would have connected to the pelvis by a ligament,” Stewart said. “It’s astonishing really. This creature has so many traits — large pair of hind appendages, large pelvis, and a connection between the pelvis and axial skeleton — that were key to the origin of walking. And while Tiktaalik probably wasn’t walking across land, it was definitely doing something new. This was a fish that could likely prop itself up and push with its hind fin.”

The new reconstruction of the skeleton also sheds light on specializations for head mobility in Tiktaalik and new details of the fish’s pelvic fin anatomy.

“It’s incredible to see the skeleton of Tiktaalik captured in such vivid detail,” said Neil Shubin, Robert R. Bensley Distinguished Service Professor of Organismal Biology and Anatomy at the University of Chicago and one of the authors of the paper. “This study sets the stage for ones that explore how the animal moved about and interacted with its environment 375 million years ago.”

Reference: “The axial skeleton of Tiktaalik roseae” by Thomas A. Stewart, Justin B. Lemberg, Emily J. Hillan, Isaac Magallanes, Edward B. Daeschler and Neil H. Shubin, 2 April 2024, Proceedings of the National Academy of Sciences.
DOI: 10.1073/pnas.2316106121

In addition to Stewart and Shubin, the research team includes Justin B. Lemberg, Emily J. Hillan, and Isaac Magallanes at The University of Chicago, and Edward B. Daeschler at Academy of Natural Sciences of Drexel University.

Support from the Brinson Foundation, the Biological Sciences Division of The University of Chicago, an anonymous donor to the Academy of Natural Sciences of Drexel University, and the U.S. National Science Foundation funded this research. Fieldwork was made possible by the Polar Continental Shelf Project of Natural Resources, Canada; the Department of Heritage and Culture, Nunavut; the hamlets of Resolute Bay and Grise Fiord of Nunavut; and the Iviq Hunters and Trappers of Grise Fiord.

Insights From JWST’s Discovery of an Einstein-Ringed Galaxy

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JWST-ER1g

JWST discovered the ancient galaxy JWST-ER1g, featuring a unique Einstein ring that aids in studying the galaxy’s high dark matter density and testing dark matter properties. Credit: Van Dokkum et al. 2023

The James Webb Space Telescope discovered an ancient galaxy, JWST-ER1g, which exhibits a phenomenon called strong gravitational lensing, forming an Einstein ring. This galaxy, rich in dark matter, provides new insights into dark matter’s properties and density.

Last September, the James Webb Space Telescope, or JWST, discovered JWST-ER1g, a massive ancient galaxy that formed when the universe was just a quarter of its current age. Surprisingly, an Einstein ring is associated with this galaxy. That’s because JWST-ER1g acts as a lens and bends light from a distant source, which then appears as a ring — a phenomenon called strong gravitational lensing, predicted in Einstein’s theory of general relativity.

Analyzing Dark Matter

The total mass enclosed within the ring has two components: stellar and dark matter components.

“If we subtract the stellar mass from the total mass, we get the dark matter mass within the ring,” said Hai-Bo Yu, a professor of physics and astronomy at the University of California, Riverside, whose team has published new work about JWST-ER1g in the journal The Astrophysical Journal Letters. “But the value for the dark matter mass seems higher than expected. This is puzzling. In our paper, we offer an explanation.”

Hai-Bo Yu, Demao Kong, and Daneng Yang

Photo shows from L to R: Hai-Bo Yu, Demao Kong, and Daneng Yang. Credit: Hai-Bo Yu, UC Riverside

The Dark Matter Halo

A dark matter halo is the halo of invisible matter that permeates and surrounds a galaxy like JWST-ER1g. Although dark matter has never been detected in laboratories, physicists are confident dark matter, which makes up 85% of the universe’s matter, exists.

“When ordinary matter — pristine gas and stars — collapses and condenses into the dark matter halo of JWST-ER1g, it may be compressing the halo, leading to a high density,” said Demao Kong, a second-year graduate student at UCR, who led the analysis. “Our numerical studies show that this mechanism can explain the high dark matter density of JWST-ER1g — more dark matter mass in the same volume, resulting in higher density.”

Unique Lensing Features and Research Opportunities

According to Daneng Yang, a postdoctoral researcher at UCR and co-author on the paper, JWST-ER1g, formed 3.4 billion years after the Big Bang, provides “a great chance to learn about dark matter.”

“This strong lensing object is unique because it has a perfect Einstein ring, from which we can obtain valuable information about the total mass within the ring, a critical step for testing dark matter properties,” he said.

Contributions of the James Webb Space Telescope

Launched on Christmas Day in 2021, NASA’s JWST is an orbiting infrared observatory. Also called Webb, it is designed to answer questions about the universe. It is the largest, most complex, and powerful space telescope ever built.

“JWST provides an unprecedented opportunity for us to observe ancient galaxies formed when the universe was young,” Yu said. “We expect to see more surprises from JWST and learn more about dark matter soon.”

The title of the open access research paper is “Cold Dark Matter and Self-interacting Dark Matter Interpretations of the Strong Gravitational Lensing Object JWST-ER1.”

Reference: “Cold Dark Matter and Self-interacting Dark Matter Interpretations of the Strong Gravitational Lensing Object JWST-ER1” by Demao Kong, Daneng Yang and Hai-Bo Yu, 11 April 2024, The Astrophysical Journal Letters.
DOI: 10.3847/2041-8213/ad394b

The study was supported by the John Templeton Foundation and the U.S. Department of Energy.