Researchers Uncover How Photosynthetic Organisms Regulate and Synthesize ATP

The redox regulation mechanism responsible for efficient production of ATP under varying light conditions in photosynthetic organisms has now been unveiled by Tokyo Tech researchers. They investigated the enzyme responsible for this mechanism and uncovered how the amino acid sequences present in the enzyme regulate ATP production. Their findings provide valuable insights into the process of photosynthesis and the ability to adapt to changing metabolic conditions.

ATP, the compound essential for the functioning of photosynthetic organisms such as plants and algae, is produced by an enzyme called "chloroplast ATP synthase" (CFoCF1). To control ATP production under varying light conditions, the enzyme uses a redox regulatory mechanism that modifies the ATP synthesis activity in response to changes in the redox state of cysteine (Cys) residues, which exist as dithiols under reducing (light) conditions, but forms a disulfide bond under oxidizing (dark) conditions. However, this mechanism has not been fully understood so far.

Now, in a study published in the Proceedings of the National Academy of Sciences, a team of researchers from Japan, led by Prof. Toru Hisabori from Tokyo Institute of Technology (Tokyo Tech), has uncovered the role of the amino acid sequences present in CFoCF1, revealing how the enzyme regulates ATP production in photosynthetic organisms.

New Study Shows Archery Appeared in Europe Thousands of Years Earlier than Previously Thought

Laure Metz making experimental bow and arrow shots with arrows armed with Neronian light points.
 Photo Credit: Ludovic Slimak

The use of bow-and-arrow technology gave humans an edge over Neanderthal neighbors in hunting game

A new study published in Science Advances contextualizes the traditions and technological knowledge of early, pioneering Homo sapiens. The study demonstrates the mastery of archery by modern populations and extends the evidence of archery in Europe back by about 40,000 years.

The researchers analyzed lithic artifacts from a cave in Mediterranean France called Grotte Mandrin, which reveals the oldest occupation of modern humans on the European continent. The study focuses on a very rich level, attributed to the Neronian culture, and testifies to Homo sapiens occupations dating back 54,000 years, interposed between numerous Neanderthal occupations in the cave before and after the modern humans. That’s roughly 10,000 years earlier than what had been previously believed to be the earliest occupation of modern humans in Europe.

The research was directed by Laure Metz, an associated researcher at UMR 7269 (UMR LAMPEA, CNRS, Aix-Marseille University), and Ludovic Slimak, CNRS researcher (UMR 5608 TRACES, Toulouse Jean Jaurès University). Metz is a UConn-affiliated researcher and former post-doctoral researcher in the UConn Department of Anthropology Deep History Lab led by Professor Christian Tryon.

Custom, 3D-printed heart replicas look and pump just like the real thing

No two hearts beat alike. The size and shape of the heart can vary from one person to the next. These differences can be particularly pronounced for people living with heart disease, as their hearts and major vessels work harder to overcome any compromised function.

MIT engineers are hoping to help doctors tailor treatments to patients’ specific heart form and function, with a custom robotic heart. The team has developed a procedure to 3D print a soft and flexible replica of a patient’s heart. They can then control the replica’s action to mimic that patient’s blood-pumping ability.

The procedure involves first converting medical images of a patient’s heart into a three-dimensional computer model, which the researchers can then 3D print using a polymer-based ink. The result is a soft, flexible shell in the exact shape of the patient’s own heart. The team can also use this approach to print a patient’s aorta — the major artery that carries blood out of the heart to the rest of the body.

To mimic the heart’s pumping action, the team has fabricated sleeves similar to blood pressure cuffs that wrap around a printed heart and aorta. The underside of each sleeve resembles precisely patterned bubble wrap. When the sleeve is connected to a pneumatic system, researchers can tune the outflowing air to rhythmically inflate the sleeve’s bubbles and contract the heart, mimicking its pumping action. 

SLAC, Stanford researchers make a new type of quantum material with a dramatic distortion pattern

This illustration shows how an electronic tug-of-war between the layers of a new quantum material has warped its atomic lattice into a dramatic herringbone-like pattern. Scientists at SLAC and Stanford who created the material are just starting to explore how this 'huge' distortion affects the material's properties.   
Illustration Credit: Greg Stewart/SLAC National Accelerator Laboratory

Created by an electronic tug-of-war between the material's atomic layers, this ‘beautiful’ herringbone-like pattern could give rise to unique features that scientists are just starting to explore.

Researchers at the Department of Energy’s SLAC National Accelerator Laboratory and Stanford University have created a new type of quantum material whose atomic scaffolding, or lattice, has been dramatically warped into a herringbone pattern.

The resulting distortions are “huge” compared to those achieved in other materials, said Woo Jin Kim, a postdoctoral researcher at the Stanford Institute for Materials and Energy Sciences (SIMES) at SLAC who led the study. 

“This is a very fundamental result, so it’s hard to make predictions about what may or may not come out of it, but the possibilities are exciting,” said SLAC/Stanford Professor and SIMES Director Harold Hwang. 

“Based on theoretical modeling from members of our team, it looks like the new material has intriguing magnetic, orbital and charge order properties that we plan to investigate further,” he said. Those are some of the very properties that scientists think give quantum materials their surprising characteristics. 

The research team described their work in a paper published in Nature today.

WVU physicists give the first law of thermodynamics a makeover

Research findings led by Paul Cassak, WVU professor and associate director of the WVU Center for KINETIC Plasma Physics, have broken new ground on how scientists can understand the first law of thermodynamics and how plasmas in space and laboratories get heated. In this photo, argon plasma glows a bluish color in a Center experiment.
Photo Credit: Brian Persinger / West Virginia University

West Virginia University physicists have made a breakthrough on an age-old limitation of the first law of thermodynamics.

Paul Cassak, professor and associate director of the Center for KINETIC Plasma Physics, and graduate research assistant Hasan Barbhuiya, both in the Department of Physics and Astronomy, are studying how energy gets converted in superheated plasmas in space. Their findings, funded by a grant from the National Science Foundation and published in the Physical Review Letters journal, will revamp scientists’ understanding of how plasmas in space and laboratories get heated up, and may have a wide variety of further applications across physics and other sciences.

The first law of thermodynamics states that energy can neither be created nor destroyed, but it can be converted into different forms.

“Suppose you heat up a balloon,” Cassak said. “The first law of thermodynamics tells you how much the balloon expands and how much hotter the gas inside the balloon gets. The key is that the total amount of energy causing the balloon to expand and the gas to get hotter is the same as the amount of heat you put into the balloon. The first law has been used to describe many things — including how refrigerators and car engines work. It’s one of the pillars of physics.”

Trawlers intermix with whale ‘supergroup’ in Southern Ocean

Fin whales surround the research vessel National Geographic Endurance in January 2022.
Video Credit: Eric Wehrmeister

Trawlers working amidst a whale ‘supergroup’ raise red flag about human-whale conflicts in a changing ocean, Stanford study says

Scientists observed close to 1,000 fin whales foraging near Antarctica, while fishing vessels trawled for krill in their midst. Without action, such encounters are likely to become more common as this endangered species recovers and krill harvesting intensifies in the Southern Ocean.

Once driven nearly to extinction, the second-largest animals of all time have recently been spotted in big numbers in the Southern Ocean, competing directly with industrial trawlers for prey, according to research led by scientists from Stanford University and Lindblad Expeditions.

Published in Ecology, the study focuses on scientists’ sighting of an enormous “supergroup” of fin whales foraging for shrimplike animals called krill northwest of the South Orkney Islands in January 2022, with four commercial fishing vessels trawling among them for the same tiny creatures.

The researchers, led by Matthew Savoca of Stanford and Conor Ryan of Lindblad Expeditions, estimate at least 830 and possibly more than 1,100 fin whales were present. This ranks among the largest groups of baleen whales ever recorded since commercial whaling decimated their populations last century.

New zirconia-based catalyst can make plastics upcycling more sustainable

A representation of the zirconia catalyst. The teal shows the mesoporous silica plates, the red represents the zirconia nanoparticles between the two sheets. The polymer chains enter the pores, contact the zirconia nanoparticles, and are cut into shorter chains.
Illustration Credit: Courtesy of Ames National Laboratory

A new type of catalyst breaks down polyolefin plastics into new, useful products. This project is part of a new strategy to reduce the amount of plastic waste and its impact on our environment, as well as recover value that is lost when plastics are thrown away. The catalyst was developed by a team from the Institute for Cooperative Upcycling of Plastic (iCOUP), a U.S. Department of Energy, Energy Frontier Research Center. The effort was led by Aaron Sadow, the director of iCOUP, scientist at Ames National Laboratory, and professor at Iowa State University; Andreas Heyden, professor at the University of South Carolina; and Wenyu Huang, scientist at Ames Lab and professor at Iowa State. The new catalyst is made only of earth-abundant materials, which they demonstrated can break carbon-carbon (CC) bonds in aliphatic hydrocarbons.

Aliphatic hydrocarbons are organic compounds made up of only hydrogen and carbon. Polyolefin plastics are aliphatic hydrocarbon materials composed of long chains of carbon atoms linked together to form strong materials. These materials are a big part of the plastic waste crisis. Wenyu Huang said, “More than half of produced plastics so far are polyolefin based.”

Simulations show aftermath of black hole collision

New simulations of two black holes colliding near the speed of light reveal the mysterious physics of what one astrophysicist calls "one of the most violent events you can imagine in the universe."

"It's a bit of a crazy thing to blast two black holes head-on very close to the speed of light," said Thomas Helfer, a postdoctoral fellow at Johns Hopkins University who produced the simulations. "The gravitational waves associated with the collision might look anticlimactic, but this is one of the most violent events you can imagine in the universe."

The work, which appears today in Physical Review Letters, is the first detailed look at the aftermath of such a cataclysmic clash, and shows how a remnant black hole would form and send gravitational waves through the cosmos.

Black hole mergers are one of the few events in the universe energetic enough to produce detectable gravitational waves, which carry energy produced by massive cosmic collisions. Like ripples in a pond, these waves flow through the universe distorting space and time. But unlike waves traveling through water, they are extremely tiny, and propagate through "spacetime," the mind-bending concept that combines the three dimensions of space with the idea of time.

Cells take on dual identities with competing factors trapped in the nucleus

Image showing one cellular response to Leptomycin B, with F-actin (pink), vimentin (yellow), and DAPI (cyan), in canine epithelial cells (MDCK I) cultured on soft hydrogels. This study demonstrates diverse epithelial-mesenchymal responses to nuclear export inhibition, including concurrent elevation of epithelial and mesenchymal cellular traits. The image was acquired on a laser-scanning confocal microscope using a 40X objective.
Image Credit: Carly Krull, Department of Biomedical Engineering

Cells migrate to different tissues for a variety of reasons, including organ development, tissue repair and the spread of cancer. Researchers in the McKelvey School of Engineering at Washington University in St. Louis has found unexpected activity in the nucleus of healthy cells that provides new insight into cell mechanics.

Amit Pathak, associate professor of mechanical engineering & materials science, working with Carly Krull, a doctoral student in biomedical engineering, and Haiyi Li, who earned a bachelor’s degree in computer science & engineering in 2022, found that when they gave the cancer drug Leptomycin B to healthy cells, the cells stopped growing, but several competing genes in their nuclei became active.

“All of a sudden, everything is happening in the nucleus,” Pathak said. “The factors that slow down the cells, the factors that make the cells faster, the factors that make the cells cohesive and the factors that generate forces in cells all became active. All of these factors are normally competing with each other, and they all became active together.”

NASA's Chandra Discovers Giant Black Holes on Collision Course

NASA’s Chandra X-ray Observatory helped identify two pairs of dwarf galaxies on track to merge.  Dwarf galaxies, which are at least about 20 times less massive than the Milky Way, likely formed larger galaxies through collisions in the early Universe.  These newly-discovered merging dwarf galaxies can be used as analogs for more distant ones that are too faint to observe.  The dwarf galaxies are on collision courses and are found in the galaxy clusters Abell 133 and Abell 1758S.
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Image Credit: X-ray: NASA/CXC/Univ. of Alabama/M. Micic et al.; Optical: International Gemini Observatory/NOIRLab/NSF/AURA

Astronomers have discovered the first evidence for giant black holes in dwarf galaxies on a collision course. This result from NASA’s Chandra X-ray Observatory has important ramifications for understanding how the first wave of black holes and galaxies grew in the early universe.

Collisions between the pairs of dwarf galaxies identified in a new study have pulled gas towards the giant black holes they each contain, causing the black holes to grow. Eventually the likely collision of the black holes will cause them to merge into much larger black holes. The pairs of galaxies will also merge into one.

Scientists think the universe was awash with small galaxies, known as “dwarf galaxies,” several hundred million years after the big bang. Most merged with others in the crowded, smaller volume of the early universe, setting in motion the building of larger and larger galaxies now seen around the nearby universe.