Chance twists ordered carbon nanotubes into ‘tornado films’

Jacques Doumani is a graduate student in applied physics at Rice and the lead author of a study published in Nature Communications.
Photo Credit: Jeff Fitlow/Rice University

Chiral materials interact with light in very precise ways that are useful for building better displays, sensors and more powerful devices. However, engineering properties such as chirality reliably at scale is still a significant challenge in nanotechnology.

Rice University scientists in the lab of Junichiro Kono have developed two ways of making wafer-scale synthetic chiral carbon nanotube (CNT) assemblies starting from achiral mixtures. According to a study in Nature Communications, the resulting “tornado” and “twisted-and-stacked” thin films can control ellipticity ⎯ a property of polarized light ⎯ to a level and in a range of the spectrum that was previously largely beyond reach.

“These approaches have granted us the ability to deliberately and consistently introduce chirality to materials that, until now, did not exhibit this property on a macroscopic scale,” said Jacques Doumani, a graduate student in applied physics at Rice and the lead author of the study. “Our methods yield thin, flexible films with tunable chiral properties.”

A good night’s sleep may help to generate false memories, a new study reveals

Sleep may play a key role in distorting memories
Photo Credit: Vlada Karpovich
Edited: Scientific Frontline 

From misremembering that movie quote to forgetting that vital ingredient from the shops for the evening dinner, the human memory is not always reliable. Now, researchers have discovered that sleep may play a key role in distorting memories, but perhaps in a good way.

In psychological experiments, false memories often arise when people are given a list of related words to memorize, and falsely remember a word being there that would have fit the category but in fact was missing.

Lure words

As part of this study, published in the journal Royal Society Open Science, researchers from the University of York’s Department of Psychology tested 488 participants on their ability to recall a list of words 12 hours after seeing them, with some of the participants being allowed to sleep in the 12-hour interim.

They found that those who had slept remembered more of the words on the list than those who had not, but they were also more likely to give words that weren't on the list, but were related. 

The related incorrect words are known as "lure words". If a list contained words like nurse, hospital and sick, the false memories may include lure words like doctor.

Shedding Light on the Synthesis of Sugars Before the Origin of Life

A recent study reveals that aldonates found in the Murchison meteorite can lead to the generation of pentoses via a non enzymatic process. A new study provides clues about primitive biochemistry and bring us closer to understanding the Origins of Life.
Illustration Credit: NASA's Goddard Space Flight Center Conceptual Image Lab.

Pentoses are essential carbohydrates in the metabolism of modern lifeforms, but their availability during early Earth is unclear since these molecules are unstable. A new study led by the Earth-Life Science Institute (ELSI) at Tokyo Institute of Technology, Japan, reveals a chemical pathway compatible with early Earth conditions and by which C6 aldonates could have acted as a source of pentoses without the need for enzymes. Their findings provide clues about primitive biochemistry and bring us closer to understanding the Origins of Life.

The emergence of life on Earth from simple chemicals is one of the most exciting yet challenging topics in biochemistry and perhaps all of science. Modern lifeforms can transform nutrients into all sorts of compounds through complex chemical networks; what's more, they can catalyze very specific transformations using enzymes, achieving a very fine control over what molecules are produced. However, enzymes did not exist before life emerged and became more sophisticated. Thus, it is likely that various nonenzymatic chemical networks existed at an earlier point in Earth's history, which could convert environmental nutrients into compounds that supported primitive cell-like functions.

Ryugu Samples Illuminate Terrestrial Weathering Effects on Primitive Meteorites

Optical images of the Ryugu sample (left) and the CI chondrite (Orgueil ; right).
Image Credit: ©Kana Amano et al.

A groundbreaking study conducted by a team of international scientists has unveiled unprecedented insights into the nature of the asteroid Ryugu and shed light on the composition of water- and carbon-rich small bodies in the solar system.

Asteroids like Ryugu are remnants of planetary embryos that never reached larger sizes, making them invaluable windows into materials that formed in the early solar system. The study centered on laboratory measurements of the samples brought back to the Earth by the Hayabusa2 spacecraft in 2020. Led by the Japan Aerospace Exploration Agency (JAXA), Hayabusa2 aimed to uncover the true nature of Ryugu and explore how astrologists can use knowledge from meteorites to interpret telescopic observations of other hydrous asteroids.

Unlike meteorites derived from similar hydrous asteroids, the Ryugu samples avoided terrestrial alteration - the interaction with oxygen and water in the Earth's atmosphere.

Advanced MRI technology detects changes in the brain after COVID-19

Ida Blystad and her colleagues examine the brain using MRI. 
Photo Credit: Emma Busk Winquist

Researchers at LiU have examined the brains of 16 patients previously hospitalized for COVID-19 with persisting symptoms. They have found differences in brain tissue structure between patients with persisting symptoms after COVID-19 and healthy people. Their findings can bring insights into the underlying mechanisms of persisting neurological problems after COVID-19.

Several previous studies of persisting problems after COVID have involved MRI brain scanning. Although researchers have found differences compared with healthy brains, these differences are not specific to COVID-19.

“It can be frustrating for me as a doctor when I understand that the patients have problems, but I can’t find an explanation because there’s nothing in the MRI scan to explain it. To me, this underlines the importance of trying other examination technologies to understand what’s happening in the brain in patients with persisting symptoms after COVID-19,” says Ida Blystad, neuroradiologist in the Department of Radiology at Linköping University Hospital and researcher affiliated with the Department of Health, Medicine and Caring Sciences at Linköping University and the Centre for Medical Image Science and Visualization (CMIV).

Belgium And Lockheed Martin Celebrate Rollout of First F-35A For Belgium

Belgium F-35A
Photo Credit: Lockheed Martin Corporation

Lockheed Martin presented Belgium's first F-35A Lightning II to the Belgian government during a rollout ceremony at Lockheed Martin's F-35 production facility. This event marks a significant milestone in the Belgian Air Force's history and strengthens the alliance between the United States and Belgium, a key NATO ally.  

"The introduction of the F-35 within the Belgian Air Force will enable us to continue to fulfil all our missions in the coming decades, in cooperation with our allies and partners in NATO, the EU and beyond," said Chief of Defense for the Belgian Armed Forces, Admiral Michel Hofman.

Building on the strong legacy of the F-16, the F-35 will provide the next generation of air power to ensure the Belgian Air Force can fulfill its NATO missions and protect the alliance's key interests. By serving as the most advanced 21st Century Security solution, the F-35 will connect assets across domains to increase situational awareness for Belgium and its key European partners. 

"We congratulate Belgium on this significant achievement," said Lt. Gen. Mike Schmidt, program executive officer, F-35 Joint Program Office. "The growth of the F-35 in Europe strengthens international partnerships, interoperability, and warfighting capability; and emphasizes the importance the aircraft provides as a deterrent against potential adversaries." 

Researchers stunned by Webb’s new high-definition look at exploded star

A roughly circular cloud of gas and dust with complex structure. The inner shell is made of bright pink and orange filaments studded with clumps and knots that look like tiny pieces of shattered glass. Around the exterior of the inner shell, there are curtains of wispy gas that look like campfire smoke. Around and within the nebula, various stars are seen as points of blue and white light. Outside the nebula, there are also clumps of dust, colored yellow in the image
Hi-Res Zoomable Image
Source/Credit: NASA, ESA, CSA, STScI, D. Milisavljevic (Purdue University), T. Temim (Princeton University), I. De Looze (University of Gent)

Like a shiny, round ornament ready to be placed in the perfect spot on the holiday tree, supernova remnant Cassiopeia A (Cas A) gleams in a new image from the NASA/ESA/CSA James Webb Space Telescope. However, this scene is no proverbial silent night — all is not calm.

Webb’s NIRCam (Near-Infrared Camera) view of Cas A displays a very violent explosion at a resolution previously unreachable at these wavelengths. This high-resolution look unveils intricate details of the expanding shell of material slamming into the gas shed by the star before it exploded.

Cas A is one of the best-studied supernova remnants in all the cosmos. Over the years, ground-based and space-based observatories, including the NASA/ESA Hubble Space Telescope, have collectively assembled a multiwavelength picture of the object’s tattered remains.

However, astronomers have now entered a new era in the study of Cas A. In April 2023, Webb’s MIRI (Mid-Infrared Instrument) started this story, revealing new and unexpected features within the inner shell of the supernova remnant. But many of those features are invisible in the new NIRCam image, and astronomers are investigating why that is.

Atomic dance gives rise to a magnet

Tong Lin (from left), Hanyu Zhu and Jiaming Luo at EQUAL lab.
Photo Credit: Jeff Fitlow/Rice University

Quantum materials hold the key to a future of lightning-speed, energy-efficient information systems. The problem with tapping their transformative potential is that, in solids, the vast number of atoms often drowns out the exotic quantum properties electrons carry.

Rice University researchers in the lab of quantum materials scientist Hanyu Zhu found that when they move in circles, atoms can also work wonders: When the atomic lattice in a rare-earth crystal becomes animated with a corkscrew-shaped vibration known as a chiral phonon, the crystal is transformed into a magnet.

According to a study published in Science, exposing cerium fluoride to ultrafast pulses of light sends its atoms into a dance that momentarily enlists the spins of electrons, causing them to align with the atomic rotation. This alignment would otherwise require a powerful magnetic field to activate, since cerium fluoride is naturally paramagnetic with randomly oriented spins even at zero temperature.

A closer look at rebel T cells

Video Credit: La Jolla Institute

Scientists at La Jolla Institute for Immunology (LJI) are investigating a talented type of T cell.

Most T cells only work in the person who made them. Your T cells fight threats by responding to molecular fragments that belong to a pathogen—but only when these molecules are bound with markers that come from your own tissues. Your influenza-fighting T cells can’t help your neighbor, and vice versa.

“However, we all have T cells that do not obey these rules,” says LJI Professor and President Emeritus Mitchell Kronenberg, Ph.D. “One of these cell types is mucosal-associated invariant T (MAIT) cells.”

Now Kronenberg and his LJI colleagues have uncovered another MAIT cell superpower: MAIT cells can recognize the same markers whether they come from humans or mice. Kronenberg calls this finding “astounding.” “Humans diverged from mice in evolution 60 million years ago,” he says.

This new research, published in Science Immunology, sheds light on the genes and nutrients that give MAIT cells their fighting power. The findings are an important step toward one day harnessing these cells to treat infectious diseases and improve cancer immunotherapies.

Researchers identify previously unknown step in cholesterol absorption in the gut

Illustration Credit: Scientific Frontline

UCLA researchers have described a previously unknown step in the complex process by which dietary cholesterol is processed in the intestines before being released into the bloodstream – potentially revealing a new pathway to target in cholesterol treatment.

Although an existing drug and statins impact part of the process, an experimental drug being studied in UCLA research labs appears to specifically target the newfound pathway, possibly adding a new approach to the cholesterol management toolbox.

“Our results show that certain proteins in the Aster family play a critical role in moving cholesterol through the absorption and uptake process,” said Dr. Peter Tontonoz, a UCLA professor and researcher in Pathology and Laboratory Medicine and Biological Chemistry, senior author of an article in Science. “The Aster pathway appears to be a potentially attractive target for limiting intestinal cholesterol absorption and reducing levels of plasma cholesterol.”

Cholesterol from food is absorbed by cells that line the inner surface of the intestines – enterocytes – where it is processed into droplets that eventually reach the bloodstream. But this journey involves a multistep process.