For the study, the team developed a new type of framework, which combines quantum mechanics and thermodynamics, to simulate the conditions to which the grain was exposed during its formation, when the solar system was a swirling disk of gas and dust known as a protoplanetary disk or solar nebula. Comparing the predictions from the model to an extremely detailed analysis of the sample’s chemical makeup and crystal structure, along with a model of how matter was transported in the solar nebula, revealed clues about the grain’s journey and the environmental conditions that shaped it along the way.

The grain analyzed in the study is one of several inclusions, known as calcium-aluminum rich inclusions, or CAIs, discovered in a sample from the Allende meteorite, which fell over the Mexican state of Chihuahua in 1969. CAIs are of special interest because they are thought to be among the first solids that formed in the solar system more than 4.5 billion years ago.

Similar to how stamps in a passport tell a story about a traveler’s journey and stops along the way, the samples’ micro- and atomic-scale structures unlock a record of their formation histories, which were controlled by the collective environments to which they were exposed.

“As far as we know, our paper is the first to tell an origin story that offers clues about the likely processes that happened at the scale of astronomical distances with what we see in our sample at the scale of atomic distances,” said Tom Zega, a professor in the University of Arizona’s Lunar and Planetary Laboratory and the first author of the paper, published in The Planetary Science Journal.

Zega and his team analyzed the composition of the inclusions embedded in the meteorite using cutting-edge atomic-resolution scanning transmission electron microscopes — one at UArizona’s Kuiper Materials Imaging and Characterization Facility, and its sister microscope located at the Hitachi factory in Hitachinaka, Japan.

The inclusions were found to consist mainly of types of minerals known as spinel and perovskite, which also occur in rocks on Earth and are being studied as candidate materials for applications such as microelectronics and photovoltaics.

Similar kinds of solids occur in other types of meteorites known as carbonaceous chondrites, which are particularly interesting to planetary scientists as they are known to be leftovers from the formation of the solar system and contain organic molecules, including those that may have provided the raw materials for life.

Precisely analyzing the spatial arrangement of atoms allowed the team to study the makeup of the underlying crystal structures in great detail. To the team’s surprise, some of the results were at odds with current theories on the physical processes thought to be active inside protoplanetary disks, prompting them to dig deeper.

“Our challenge is that we don’t know what chemical pathways led to the origins of these inclusions,” Zega said. “Nature is our lab beaker, and that experiment took place billions of years before we existed, in a completely alien environment.”

Zega said the team set out to “reverse-engineer” the makeup of the extraterrestrial samples by designing new models that simulated complex chemical processes, which the samples would be subjected to inside a protoplanetary disk.

“Such models require an intimate convergence of expertise spanning the fields of planetary science, materials science, mineral science and microscopy, which was what we set out to do,” added Krishna Muralidharan, a study co-author and an associate professor in the UArizona’s Department of Materials Science and Engineering.

Based on the data the authors were able to tease from their samples, they concluded that the particle formed in a region of the protoplanetary disk not far from where Earth is now, then made a journey closer to the sun, where it was progressively hotter, only to later reverse course and wash up in cooler parts farther from the young sun. Eventually, it was incorporated into an asteroid, which later broke apart into pieces. Some of those pieces were captured by Earth’s gravity and fell as meteorites.

The samples for this study were taken from the inside of a meteorite and are considered primitive — in other words, unaffected by environmental influences. Such primitive material is believed to not have undergone any significant changes since it first formed more than 4.5 billion years ago, which is rare. Whether similar objects occur in asteroid Bennu, samples of which will be returned to Earth by the UArizona-led OSIRIS-REx mission in 2023, remains to be seen. Until then, scientists rely on samples that fall to Earth via meteorites.

“This material is our only record of what happened 4.567 billion years ago in the solar nebula,” said Venkat Manga, a co-author of the paper and an assistant research professor in the UArizona Department of Materials Science and Engineering. “Being able to look at the microstructure of our sample at different scales, down to the length of individual atoms, is like opening a book.”

The authors said that studies like this one could bring planetary scientists a step closer to “a grand model of planet formation” — a detailed understanding of the material moving around the disk, what it is composed of, and how it gives rise to the sun and the planets.

Powerful radio telescopes like the Atacama Large Millimeter/submillimeter Array, or ALMA, in Chile now allow astronomers to see stellar systems as they evolve, Zega said.

“Perhaps at some point we can peer into evolving disks, and then we can really compare our data between disciplines and begin answering some of those really big questions,” Zega said. “Are these dust particles forming where we think they did in our own solar system? Are they common to all stellar systems? Should we expect the pattern we see in our solar system — rocky planets close to the central star and gas giants farther out — in all systems?

“It’s a really interesting time to be a scientist when these fields are evolving so rapidly,” he added. “And it’s awesome to be at an institution where researchers can form transdisciplinary collaborations among leading astronomy, planetary and materials science departments at the same university.”

“We’ve identified a previously unrecognized pattern of tectonic deformation on Venus, one that is driven by interior motion just like on Earth,” says Paul Byrne, associate professor of planetary science at North Carolina State University and lead and co-corresponding author of the work. “Although different from the tectonics we currently see on Earth, it is still evidence of interior motion being expressed at the planet’s surface.”

The finding is important because Venus has long been assumed to have an immobile solid outer shell, or lithosphere, just like Mars or Earth’s moon. In contrast, Earth’s lithosphere is broken into tectonic plates, which slide against, apart from, and underneath each other on top of a hot, weaker mantle layer.

Byrne and an international group of researchers used radar images from NASA’s Magellan mission to map the surface of Venus. In examining the extensive Venusian lowlands that make up most of the planet surface, they saw areas where large blocks of the lithosphere seem to have moved: pulling apart, pushing together, rotating and sliding past each other like broken pack ice over a frozen lake.

The team created a computer model of this deformation, and found that sluggish motion of the planet’s interior can account for the style of tectonics seen at the surface.

“These observations tell us that interior motion is driving surface deformation on Venus, in a similar way to what happens on Earth,” Byrne says. “Plate tectonics on Earth are driven by convection in the mantle. The mantle is hot or cold in different places, it moves, and some of that motion transfers to Earth’s surface in the form of plate movement.

“A variation on that theme seems to be playing out on Venus as well. It’s not plate tectonics like on Earth — there aren’t huge mountain ranges being created here, or giant subduction systems — but it is evidence of deformation due to interior mantle flow, which hasn’t been demonstrated on a global scale before.”

The deformation associated with these crustal blocks could also indicate that Venus is still geologically active.

“We know that much of Venus has been volcanically resurfaced over time, so some parts of the planet might be really young, geologically speaking,” Byrne says. “But several of the jostling blocks have formed in and deformed these young lava plains, which means that the lithosphere fragmented after those plains were laid down. This gives us reason to think that some of these blocks may have moved geologically very recently — perhaps even up to today.”

The researchers are optimistic that Venus’ newly recognized “pack ice” pattern could offer clues to understanding tectonic deformation on planets outside of our solar system, as well as on a much younger Earth.

“The thickness of a planet’s lithosphere depends mainly upon how hot it is, both in the interior and on the surface,” Byrne says. “Heat flow from the young Earth’s interior was up to three times greater than it is now, so its lithosphere may have been similar to what we see on Venus today: not thick enough to form plates that subduct, but thick enough to have fragmented into blocks that pushed, pulled, and jostled.”

NASA and the European Space Agency recently approved three new spacecraft missions to Venus that will acquire observations of the planet’s surface at much higher resolution than Magellan. “It’s great to see renewed interest in the exploration of Venus, and I’m particularly excited that these missions will be able to test our key finding that the planet’s lowlands have fragmented into jostling crustal blocks,” Byrne says.

In a study, a Penn State-led team of researchers reports it has taken a step toward overcoming the challenge of inexpensive hydrogen production by using supercomputers to find materials that could help accelerate hydrogen separation when water is exposed to light, a process called photocatalysis.

Both electricity and solar energy can be used to separate hydrogen from water, which is made up of two hydrogen atoms and an oxygen atom, according to Ismaila Dabo, associate professor of materials science and engineering. Institute for Computational and Data Sciences (ICDS) affiliate and co-funded faculty member of the Institutes of Energy and the Environment. Using sunlight to generate electricity to create hydrogen — or electrolysis — , which, in turn, would likely be converted back into electricity may not be technically advantageous or economically effective. While using solar energy directly to produce hydrogen from water — or photocatalysis — avoids that extra step, researchers have yet to be able to use direct solar hydrogen conversion in a way that would compete with carbon-based fuels, such as gasoline.

The researchers, who report their findings in Energy and Environmental Science, used a type of computational approach called high-throughput materials screening to narrow a list of more than 70,000 different compounds down to six promising candidates for those photocatalysts, which, when added to water, can enable the solar hydrogen production process, said Dabo.

They examined the compounds listed in the Materials Project database, an online open-access repository of known and predicted materials. The team developed an algorithm to identify materials with properties that would make them suitable photocatalysts for the hydrogen production process. For example, the researchers investigated the ideal energy range — or the band gap — for the materials to absorb sunlight. Working closely with Héctor Abruña, professor of chemistry at Cornell; Venkatraman Gopalan, professor of materials science and engineering at Penn State; and Raymond Schaak, professor of chemistry at Penn State; they also looked at materials that could effectively dissociate water, as well as materials that offered good chemical stability.

“We believe the integrated computational-experimental workflow that we have developed can considerably accelerate the discovery of efficient photocatalysts,” said Yihuang Xiong, graduate research assistant and co-first author of the paper. “We hope that, by doing so, we will be able to reduce the cost of hydrogen production.”

Dabo added the team focused on oxides — chemical compounds made up of at least one oxygen atom — because they can be synthesized in a reasonable amount of time using standard processes. The work required collaborations from across disciplines, which served as a learning experience for the research team.

“I found it very rewarding to have worked on such a collaborative project,” said Nicole Kirchner-Hall, doctoral student and co-author of the paper. “As a graduate student specializing in computational material science, I was able to predict possible photocatalytic materials using calculations and work with experimental collaborators here at Penn State and other institutions to co-validate our computational predictions.”

Other researchers have previously conducted an economic analysis on several options of using solar energy to produce electricity and determined that solar could drop the price of hydrogen production to compete with gasoline, said Dabo.

“Their essential conclusion was that if you were able to develop this technology, you could produce hydrogen at the cost of $1.60 to $3.20 per equivalent gallon of gasoline,” said Dabo. “So, compare that to gasoline, which is around $3 a gallon, if this works, you could pay as low as $1.60 for about the same amount of energy as a gallon of gas in the ideal case scenario.”

He added that if a catalyst can help boost solar hydrogen production, this could lead to a hydrogen price that is competitive with gasoline.

The team relied on Penn State ICDS’s Roar supercomputer for the computations. According to Dabo, computers represent an important tool in speeding up the process to find the right materials to be used in specific processes. This computationally driven, data-intensive method could represent a revolution in efficiency over the painstaking trial-and-error approach.

“When Thomas Edison wanted to find materials for the light bulb, he looked at just about every material under the sun until he found the right material for the light bulb,” said Dabo. “Here we’re trying to do the same thing, but in a way to use computers to accelerate that process.”

He added that computers will not replace experimentation.

“Computers can make the recommendations as to what materials will be the most promising and then you still need to do the experimental study,” said Dabo.

Dabo said he expects the power of computers will streamline the process of finding the best candidates and dramatically cut the time it takes to design materials in the lab to bring them to market to address needs.

The researchers evaluated machine learning algorithms to make suggestions for chemicals that could be synthesized and used as catalysts in solar hydrogen production. Based on this preliminary investigation, they suggest future work may focus on developing machine learning models to improve the chemical screening process.

Dabo also added that they may look at chemical compounds outside of oxides to determine if they might serve as catalysts for solar hydrogen production.

“So far, we did one cycle of this process on oxides — essentially rusted metals — but there are a lot of compounds that could be made that aren’t based on oxygen,” said Dabo. “For example, there are compounds based on nitrogen or sulfur, that we could explore.”

Overuse of antibiotics in the last century has led to a rise in bacterial resistance, leading to many bacterial infections that are no longer treatable with current antibiotics. In the United States each year, 2.8 million people are diagnosed with a bacterial infection that is resistant to one or more antibiotics, and 35,000 people die due to the resistant infection according to the Centers for Disease Control and Prevention.

“One method of combatting antibiotic resistance is using a combination drug/inhibitor therapy,” said Caitlyn Thomas, a Ph.D. candidate in chemistry, presenting author on the study. An example of this type of therapy is Augmentin, a prescription antibiotic used to treat bacterial infections of the respiratory tract, which is composed of the antibiotic amoxicillin and the inhibitor clavulanic acid. Clavulanic acid inactivates a key protein that the bacterium uses to become resistant to amoxicillin. With the bacterial protein inactivated, the antibiotic — amoxicillin — is left to kill the bacteria, thereby treating the infection.

Before any new inhibitor can be used in the clinic, scientists need to have a complete understanding of how the inhibitor works. In the current study, Thomas and her team studied a bacterial protein called metallo-beta-lactamase, which renders many clinical strains of bacteria resistant to all penicillin-like antibiotics. Penicillin-like antibiotics make up over 60% of the entire antibiotic arsenal that is available to treat bacterial infections.

While many research labs throughout the world are attempting to create new inhibitors that inactivate metallo-beta-lactamases, Thomas and collaborators instead analyze how these new inhibitors work. “Because metallo-beta-lactamases contain two metal ions we are able to use a variety of spectroscopic techniques to study them,” said Thomas. “These experiments give us more insight into how to inhibitor behaves and whether it could potentially be a candidate for clinical use in the future.”

Hundreds of potential inhibitors have been reported in the literature, and several patents have been filed dealing with metallo-beta-lactamase inhibitors. Some of the reported inhibitors work by removing a required component of the metallo-beta-lactamase. These same inhibitors may remove this same required component of other proteins in humans, causing serious side effects. Other inhibitors bind directly to the metallo-beta-lactamase and inactivate the protein; inhibitors of this type are optimal for any new inhibitor that could be used in the clinic.

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In pulmonary TB, the most common form of active TB disease, the Mycobacterium tuberculosis bacteria causes the formation of sites of high bacterial load, known as cavities. These cavities are poorly penetrated by TB drugs. After TB treatment is complete, there is likely to be tissue damage within the lungs that can lead to further lung problems such as permanent respiratory dysfunction leading to difficulty in breathing, stiffness in the lungs and bronchiectasis, which can make people cough up blood.

Researchers from NUS Yong Loo Lin School of Medicine’s Infectious Diseases Translational Research Programme have discovered that the use of a common antibiotic, doxycycline, in combination with TB drug treatment, reduces the size of lung cavities and accelerates markers of lung recovery.

In the Phase 2 double-blind trial conducted at the National University Hospital and TB Control Unit, the treatment was found to be safe, with side effects similar to patients on placebo pills. The study shows promise in delivering a new standard-of-care which can potentially prevent long term complications and the study team is seeking funds for a fully-powered larger scale Phase 3 trial to verify these findings.

“Pulmonary TB patients tend to suffer from lung damage after TB, which is associated with mortality, and poorer quality of life. Doxycycline is a cheap and widely available antibiotic that can decrease lung damage, and potentially improve quality of life for these patients,” said Assistant Professor Catherine Ong, Principal Investigator of the study and member of the Infectious Diseases Translational Research Programme (TRP) at NUS Medicine. The study findings were published in the Journal of Clinical Investigation.

Professor Paul Tambyah, who was also involved in the study and is Deputy Director of the Infectious Diseases TRP commented, “While we have been able to successfully treat most cases of TB for the last few decades, we have seen many people suffer the complications of the lung damage from the original TB infection. If this common drug, doxycycline, can help prevent the complications of “Long TB” (to use a term currently in vogue), this will really help a lot of patients in Singapore and worldwide.”

The Infectious Diseases TRP aims to provide a holistic, patient-centric approach to infectious diseases that are relevant to Singapore and the region. The Programme focuses on programmatic research areas including pathogen evolution and transmission, host-microbe interactions and vaccine and therapeutics development.

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Materials provided by National University of Singapore, Yong Loo Lin School of Medicine. Note: Content may be edited for style and length.