. Scientific Frontline

Thursday, December 2, 2021

Color-changing magnifying glass gives clear view of infrared light

Nano-antennas convert invisible infrared into visible light 
Credit: NanoPhotonics Cambridge/Ermanno Miele, Jeremy Baumberg
Detecting light beyond the visible red range of our eyes is hard to do, because infrared light carries so little energy compared to ambient heat at room temperature. This obscures infrared light unless specialized detectors are chilled to very low temperatures, which is both expensive and energy-intensive.

Now researchers led by the University of Cambridge have demonstrated a new concept in detecting infrared light, showing how to convert it into visible light, which is easily detected.

In collaboration with colleagues from the UK, Spain and Belgium, the team used a single layer of molecules to absorb the mid-infrared light inside their vibrating chemical bonds. These shaking molecules can donate their energy to visible light that they encounter, ‘upconverting’ it to emissions closer to the blue end of the spectrum, which can then be detected by modern visible-light cameras.

The results, reported in the journal Science, open up new low-cost ways to sense contaminants, track cancers, check gas mixtures, and remotely sense the outer universe.

The challenge faced by the researchers was to make sure the quaking molecules met the visible light quickly enough. “This meant we had to trap light really tightly around the molecules, by squeezing it into crevices surrounded by gold,” said first author Angelos Xomalis from Cambridge’s Cavendish Laboratory.

Researchers engineer magnetic complexity into atomically thin magnets

Layering two bilayer flakes of chromium triiodide
 and twisting them a tiny amount offsets the chromium atoms
within the material and creates a more complex magnetic moment.
Image credit: Zhao Lab, University of Michigan

Magnets are used in so many of our everyday objects including cell phones and in the strip of a credit card or a hotel key. They even power the engine in your vacuum.

And as most computers use magnets to store information, finding ever thinner magnets is key to faster, lighter electronics. Graphene, a material that is one atom thick, was discovered in 2004 and won the 2010 Nobel Prize in physics. While graphene is not magnetic itself, it triggered the interest of searching for atomically thin magnets.

In 2017, scientists found an ultrathin, magnetic material just three atoms, or one atomic unit, thick. But this material, called chromium triiodide, had a simple magnetic moment arrangement—the spin of the electrons within the material all aligned in the same direction, either up or down—which means it’s not able to store large amounts of information.

Now, University of Michigan physicist Liuyan Zhao and her team have developed a way to create a more complex magnetic moment arrangement in chromium triiodide, allowing this atomically thin material to store more information and to perhaps process information faster. Their results are published in Nature Physics.

“Over time, people began looking for smaller sizes and more complex forms of magnets in order to make our computers and electronics smaller, thinner and faster. To do this, the material that stores data or does information processing needs to also get smaller and smaller, while their magnetic forms should be more and more exotic,” Zhao said. “In very big, bulky materials, people find all kinds of magnetic forms called spin textures. So in this ultrathin material, we asked: Can we also create those kinds of complex spin textures so that we can store more information?”

To do this, Zhao and her team created an artificial sample by tearing a micron-sized (one millionth of a meter) flake of chromium triiodide into two. The flake of chromium triiodide is bilayer, which means the material is two atomic units, or six atoms, thick. Then, they layered one piece on top of the other and rotated it a tiny amount. Each flake is composed of a crystalline lattice structure, and when one structure is laid over another and rotated a small amount, the crystalline structures interfere with each other and form a periodic structure with a longer wavelength. This also creates an angular mismatch between the two flakes and leads to a superlattice with a longer period called a moiré superlattice.

Nanoracks, Voyager Space, And Lockheed Martin Awarded NASA Contract To Build First-Of-Its-Kind Commercial Space Station

Nanoracks, Voyager Space, and Lockheed Martin Awarded NASA Contract to Build First-of-its-Kind Commercial Space Station

Starlab to anchor NASA’s Commercial Low-Earth Orbit Destinations project as the space economy continues to grow

Nanoracks, in collaboration with Voyager Space and Lockheed Martin [NYSE: LMT], has been awarded a $160 million contract by NASA to design its Starlab commercial space station as part of the agency’s Commercial Low-Earth Orbit (LEO) Development program. Starlab will enable NASA’s initiative to stimulate the commercial space economy and provide science and crew capabilities prior to the retirement of the International Space Station (ISS).

“While today marks a major milestone for Nanoracks and our Starlab team, the impact goes far beyond this award,” said Dr. Amela Wilson, CEO at Nanoracks. “To receive this support from NASA validates over a decade of Nanoracks’ hard work forging commercial access to space, bringing over 1300 commercial payloads from 30 nations to the ISS. This opportunity opens far-reaching possibilities for critical research and commercial industrial activity in LEO. We are honored to be selected as one of three awardees to work with NASA, and we cannot wait to bring our existing global commercial customer base to Starlab.”

TESS discovers a planet the size of Mars but with the makeup of Mercury

Caption:An illustration of a red dwarf star orbited by an exoplanet.
Credits: NASA/ESA/G. Bacon (STScI)

Ultra-short-period planets are small, compact worlds that whip around their stars at close range, completing an orbit — and a single, scorching year — in less than 24 hours. How these planets came to be in such extreme configurations is one of the continuing mysteries of exoplanetary science.

Now, astronomers have discovered an ultra-short-period planet (USP) that is also super light. The planet is named GJ 367 b, and it orbits its star in just eight hours. The planet is about the size of Mars, and half as massive as the Earth, making it one of the lightest planets discovered to date.

Orbiting a nearby star that is 31 light years from our own sun, GJ 367 b is close enough that researchers could pin down properties of the planet that were not possible with previously detected USPs. For instance, the team determined that GJ 376 b is a rocky planet and likely contains a solid core of iron and nickel, similar to Mercury’s interior.

Due to its extreme proximity to its star, the astronomers estimate GJ 376 b is blasted with 500 times more radiation than what the Earth receives from the sun. As a result, the planet’s dayside boils at up to 1,500 degrees Celsius. Under such extreme temperatures, any substantial atmosphere would have long vaporized away, along with any signs of life, at least as we know it.

Stem cell-based treatment produces insulin in patients with Type 1 diabetes

Sentinel device in the Kieffer Lab.
Credit:ViaCyte
In the first study of its kind, a team of researchers at the University of British Columbia’s faculty of medicine and Vancouver Coastal Health (VCH) has helped to demonstrate that a stem cell-based treatment delivered through an implantable device can produce insulin in the human body.

The treatment was provided to B.C. patients living with a severe form of Type 1 diabetes as part of a multi-year clinical trial. The study results were published today in Cell Stem Cell.

“Our findings demonstrate the incredible potential of this stem cell-based treatment. With further research, this treatment could one day eliminate dependence on insulin injections and transform the management of Type 1 diabetes,” said the study’s senior author Dr. Timothy Kieffer, professor in UBC faculty of medicine’s departments of surgery and cellular and physiological sciences, who was recently appointed as ViaCyte’s chief scientific officer.

At the start of the UBC-VCH study, 15 patients underwent surgery at Vancouver General Hospital, where several cell-containing devices developed by California-based biotechnology company ViaCyte were implanted just below the skin. Each device—about seven centimeters long and no thicker than a credit card—contained millions of lab-grown cells that originally came from a single stem cell line and were ‘coached’ into maturing into beta cells. Beta cells are responsible for making insulin, the hormone that controls a person’s blood sugar.

Volcanic eruptions drove severe mass extinction, say scientists

Abrupt climate change ~450-440 million years ago caused the demise of the trilobite, Selenopeltis (pictured, in Oxford University Museum of Natural History).
Photograph: Dr Tom Gernon

Two intense periods of volcanism triggered a period of global cooling which caused one of the most severe mass extinctions in Earth history, according to new research.

The study, published in Nature Geoscience, was conducted by scientists at the University of Plymouth, the University of Oldenburg, the University of Southampton and the University of Leeds.

They examined the effects of volcanism on ocean chemistry during a period of extreme environmental change around 450 million years ago.

This period brought about intense planetary cooling, which culminated in a glaciation and the major ‘Late Ordovician Mass Extinction’. It led to the loss of about 85% of species dwelling in the oceans, reshaping the course of evolution of life on Earth.

Through their research, the team identified that two exceptionally large pulses of volcanic activity across the globe – occurring in parts of present-day North America and South China – coincided very closely with two peaks in glaciation and extinction separated by about 10 million years.

New testing method yields pathway to better, longer-lasting batteries

This illustration shows how a team at Sandia National Laboratories used Kelvin probe force microscopy to locate places where electron flows get stuck, potentially leading to engineering longer-lasting, more efficient batteries.
Illustration courtesy of S. Kelley/National Institute of Standards and Technology.
Using a microscopic method for measuring electrical potential, a team of scientists at Sandia National Laboratories may have discovered how to make a longer-lasting, more efficient battery.

The team of Elliot Fuller, Josh Sugar and Alec Talin detailed their findings in an article published in American Chemical Society Energy Letters.

“One of the challenges with solid-state batteries is that at the boundaries between different parts of the battery — a cathode and a layer of ion-conducting electrolyte, let’s say — something interferes with the flow of electrons,” Talin said.

Solid-state batteries employ solid electrolytes instead of electrochemical gels and liquids and generally power small electronics. Most researchers suspected that there was a loss of voltage or electrical potential at interfaces within the battery, but not which interface was responsible for most of the impedance in the battery. The team started work five years ago to get some clarity.

“There were two main motivations for this. The first was fundamental: we want to have good models for batteries that we can use to develop better materials,” Talin explained. “The second thing was to figure out how we can engineer the interfaces to make them less impeding. In our case, it really has to do a lot with how fast lithium ions can move in the Si anode used in the study.”

Covid-19 studies should record women’s menstrual changes, recommend researchers

Large scale COVID-19 studies and clinical trials should collect data on menstrual changes, according to new research which evaluated current evidence. The findings, published in the International Journal of Epidemiology and led by University of Bristol researchers, say there is an important public health imperative for accurate scientific investigation of menstrual changes in relation to the COVID-19 pandemic.

Researchers from the universities of Bristol, Edinburgh and Oxford sought to evaluate the existing anecdotal and scientific literature on menstrual cycle feature changes in the COVID-19 pandemic and provide suggestions for future research. They conducted a comprehensive review of current literature and found just 12 studies that had reported on menstrual changes in relation to the pandemic in general and/or COVID-19 specifically. None of the COVID-19 vaccine trials has collected data on menstrual changes.

Anecdotes shared online and data from the MHRA’s Yellow Card scheme for adverse drug reactions, suggested that many women and people who menstruate have experienced disruptions to their menstrual cycles since the start of the pandemic, either due to pandemic-related factors like stress and behavior changes and/or due to COVID-19 illness itself or COVID-19 treatments and vaccines.

However, the researchers say from what is known about how the menstrual cycle works and how it can be disrupted by factors like stress, weight changes, infection, and inflammation (e.g. following vaccination), they strongly suspect that any pandemic-related changes will be short term with no serious or lasting effect on health and fertility.

Lunar radar data uncovers new clues about moon’s ancient past

A full moon is pictured above the Earth's horizon as the International Space Station orbited 262 miles over the Pacific Ocean off the coast of Japan.
Credit: NASA

The dusty surface of the moon — immortalized in images of Apollo astronauts’ lunar footprints — formed as the result of asteroid impacts and the harsh environment of space breaking down rock over millions of years. An ancient layer of this material, covered by periodic lava flows and now buried under the lunar surface, could provide new insight into the Moon’s deep past, according to a team of scientists.

“Using careful data processing, we found interesting new evidence that this buried layer, called paleoregolith, may be much thicker than previously expected,” said Tieyuan Zhu, assistant professor of geophysics at Penn State. “These layers have been undisturbed since their formation and could be important records for determining early asteroid impact and volcanic history of the moon.”

The team, led by Zhu, conducted new analysis of radar data collected by China’s Chang’e 3 mission in 2013, which performed the first direct ground radar measurements on the moon.

The researchers identified a thick layer of paleoregolith, roughly 16 to 30 feet, sandwiched between two layers of lava rock believed to be 2.3 and 3.6 billion years old. The findings suggest the paleoregolith formed much faster than previous estimates of 6.5 feet per billion years, the scientists said.

Interactive tool helps people decide how best to protect themselves and others from COVID-19

Credit: Will Stahl-Timmins, The BMJ
A new interactive graphic developed by UK researchers and published by The BMJ will help people decide what to do in everyday situations to protect themselves, and others, from COVID-19.

Based on estimates provided by 26 international experts, it shows the different pathways that may be taken by the virus that causes COVID-19 when it transfers between two people.

It is designed to help illustrate the risks of catching COVID-19 in different scenarios - and what can be done to reduce those risks - based on the available evidence.

As well as the areas of scientific consensus, it also conveys the uncertainties and the disagreement that exists between experts about how the virus behaves, how it is transmitted, and how we can best reduce the likelihood of transmission through personal and social measures.

The researchers say the tool should support decision-makers and the public to make informed decisions about how to reduce virus transmission in different contexts, such as how to make a workplace or a public area as safe as it can be while still being open and functional.

To create the tool, the researchers, led by the University of Cambridge, consulted 26 experts from a range of disciplines and countries, asking them for every value needed to underpin the graphic.

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