Tech

Durham, NC -- Type 2 diabetes patients who are not overweight and who have had the disorder for less than a decade can benefit from stromal stem cells transplanted from their own bone marrow, according to a study published today in STEM CELLS Translational Medicine.

In a randomized clinical trial at Vinmec Research Institute of Stem Cell and Gene Technology in Hanoi, Vietnam, researchers investigated the safety and potential therapeutic value of administering bone marrow stromal stem cells to patients with Type 2 diabetes. In each case, the cells were autologous, or taken from the patients' own bodies.

A total of 30 adult patients with different body mass indexes whose Type 2 diabetes histories varied from one to 25 years were recruited for the study. Each received two infusions of the cells intravenously or by injection into an artery that supplies blood to the pancreas.

Researchers monitored the patients for 48 hours and re-examined them at one-month, three-month, six-month and one-year intervals. No significant problems were detected in the patients' health as a result of the treatment and they appeared to benefit equally from both infusion methods.

"Our patients tolerated the procedure well and showed short-term reductions in their blood glucose levels after the treatment," said Liem Nguyen, the institute's research director. "We also found that some of them were able to temporarily reduce the dosage of their diabetes medications."

Some 420 million people worldwide have Type 2 diabetes, a disorder accounting for about 90 percent of all diabetes cases that often leads to disability or death. People with Type 2 diabetes cannot make good use of the insulin their bodies produce. Increased physical activity and a healthy diet can improve the disorder in some people, but many must take insulin or drugs to control their blood glucose levels.

Patients in the Vinmec study were classified into three groups based on the diabetes medicines they were regularly taking before their stem cell infusions. Some were maintaining their blood glucose levels with insulin only. Others were taking drugs but no insulin, and still others were taking a combination of insulin and drugs.

After receiving the treatment, more than half of the patients were able to lower the doses of their diabetes medicines.

"Our trial, the first to link the outcomes of autologous bone marrow stromal stem cell transplantation with body mass index and Type 2 diabetes duration, shows the procedure is safe and opens the way for other clinical trials exploring the potential benefits of this treatment in non-obese patients who have had the disorder less than 10 years," Nguyen said.

Bone marrow stromal stem cells, also known as mesenchymal stem cells, play a key role in the body's immune response and can transform into connective tissue cells in any organ. Over the past 50 years, they have emerged as a versatile cell source in the field of regenerative medicine.

"The results of this randomized clinical trial for patients with Type 2 diabetes and the injection of their own bone marrow stromal stem cells is encouraging and potentially may add to the treatment arsenal for this chronic disease that affects so many worldwide," said Anthony Atala, M.D., Editor-in-Chief of STEM CELLS Translational Medicine and director of the Wake Forest Institute for Regenerative Medicine. "Of special interest is the short-term efficacy in patients with a history of Type 2 diabetes for less than 10 years and a bone mass index of less than 23. This work opens opportunities for future research to further investigate this area of work."

A new study in the journal Sleep finds that increased evening screen time during the Covid-19 lockdown negatively affects sleep quality.

During the lockdown period in Italy, daily internet traffic volume almost doubled compared to the same time in the previous year. Researchers here conducted a web-based survey of 2,123 Italian residents during the third and seventh week of Italy's first national lockdown. The survey ran in the third week of lockdown (March 25th - 28th, 2020) and evaluated sleep quality and insomnia symptoms, using the Pittsburgh Sleep Quality Index and the Insomnia Severity Index as means of measurement. The second assessment survey, in the seventh week of lockdown (April 21st - 27th, 2020), inquired about usage of electronic devices in the two hours before falling asleep, in addition to repeating the sleep questionnaires.

Of the participants surveyed, 92.9% reported an increase in their electronic device usage between the first and second surveys. These participants showed decreased sleep quality, an increase in insomnia symptoms, shorter total sleep times, and later bedtimes and rising times. Researchers found an increased prevalence of poor sleepers and respondents with moderate to severe insomnia symptoms only within this group of respondents.

Some 7.1% of participants reported a decrease in evening screen time between the first and second survey, and conversely reported improved sleep quality and fewer symptoms of insomnia. This subgroup also demonstrated a decrease in the prevalence of poor sleepers and moderate/severe insomnia symptoms. These respondents went to bed consistently earlier after four weeks of home confinement.

Survey respondents who reported no change in their screen time exposure likewise showed no variations in their sleep habits. Notably, this group of responders had the best sleep quality and fewest insomnia symptoms in the first survey results, suggesting that the lockdown exacerbated negative sleep conditions for people already suffering from poor sleep quality.

Dr. Federico Salfi, Ph.D. student and first author of the paper, says "The overuse of electronic devices in the hours before sleep was a deeply rooted habit in our society already before the pandemic emergency, in particular among young people. In our opinion, the current period of social distancing added fuel to the fire."

Prof. Michele Ferrara, Director of the Laboratory of Sleep Psychophysiology and Cognitive Neuroscience at the University of L'Aquila, says "The evidence of a strong relationship between screen habits and the time course of sleep disturbances during the lockdown period suggests that, now, more than never, raising public awareness about the risks of evening exposure to electronic devices could be crucial to preserve general sleep health. This applies to both the ongoing pandemic and the future, as electronic technologies will find more and more space in our daily routine."

A study published in the journal Pediatrics shows the combination of two early reading programs had positive effects on preschool students entering kindergarten in Cincinnati Public Schools over a three-year period.

The two early reading programs are: Reach Out and Read, through which children receive a new book and guidance about reading at home during well-visits from newborn through age 5; and Dolly Parton's Imagination Library, which mails new books to the child's home once a month from birth through age 5. Each of these is well-established at Cincinnati Children's Hospital Medical Center and across the nation.

"With this early study, we suggest that when combined and sustained, these two programs have the potential for effectively supporting the development of preliteracy skills of large populations of at-risk children, improving kindergarten readiness, and, ultimately, success in school and life," said Greg Szumlas, MD, of the Division of General and Community Pediatrics at Cincinnati Children's.

"I can't stress enough to parents the importance of reading with your child, starting at birth," Szumlas added. "Just a few minutes a day, reading aloud, and interacting with your child over books can make a huge difference in helping them prepare and be ready for kindergarten."

Cincinnati Children's initiated the unique combination of the two programs in July 2015 with the participation of 23 health clinics throughout the city and funding from Every Child Capital. Researchers analyzed the results of the kindergarten readiness assessment (KRA), a standardized state test for all children entering kindergarten at a public school, of program participants over the course of three school years¬¬ - 2016-2017, 2017-2018, and 2018-2019.

Over 3200 children participated in the combined program during the three-year period. For a sample of participants, scores on the kindergarten readiness assessment were analyzed and compared to the school district average. Results showed an increase of 15.4 percentage points between the 2016-2017 school year and the 2018-2019 school year for students participating in the program, while the school district average increased by only 3.8 percent during this same time period.

"Even though the percentages for the entire district were higher than our program participants, the increase in percentage points over that three-year period represents significant progress and improvement," Szumlas said. "This early study suggests that pediatric health care providers are positioned to influence the literacy developmental trajectory of children long before they start school and that literacy promotion should be considered a routine part of primary care."

Lisha Lungelow, a Cincinnati Children's social worker in the Pediatric Primary Care Clinic, enrolled her son, Jordan, in the Reach Out and Read/Imagination Library program when he was 13 months old back in 2016.

"When he came to me, he didn't really have any exposure to books," Lungelow said. "Reading was a way for us to connect and bond. He loved getting the books in the mail and seeing his name on them."

When Jordan entered kindergarten last year, Lungelow believed he was ready and credits his exposure to books through the combination program.

"When he was in kindergarten, I went to grab a book for us to read," Lungelow said. "Jordan took it from me, and he read the book to me. I can't even explain the joy that brought me. It was really great."

CHAMPAIGN, Ill. -- Many species of ground-dwelling beetles, ladybugs, hoverflies, damsel bugs, spiders and parasitic wasps kill and eat pest species that routinely plague farmers, including aphids and corn rootworm larvae and adults. But the beneficial arthropods that live in or near cropped lands also are susceptible to insecticides and other farming practices that erase biodiversity on the landscape.

A new study reveals that beneficial arthropods are nearly twice as abundant and diverse in uncultivated field edges in the spring as they are in areas that are cropped - if those field edges are rich in an array of flowers and other broad-leaved plants and not just mowed grass. The findings are reported in the Journal of Insect Science.

Former graduate student Scott Clem, who led the research with University of Illinois Urbana-Champaign entomology professor Alexandra Harmon-Threatt, captured the beneficial bugs as they emerged from the soil in early spring. The study focused on overwintering arthropods in organic farm fields and field edges in Illinois, as the use of pesticides may wipe out many of the beneficial creatures, said Clem, who earned a Ph.D. in May.

Predatory arthropods that overwinter near cropped areas are immediately available in spring and may be more useful to farmers than insects and other arthropods that disperse in agricultural fields during the growing season, Clem said.

"A benefit of understanding overwintering is that those arthropods that emerge in the spring may be more inclined to feed on pests when pest populations are low," he said. "And so, they may be more likely to nip pest populations in the bud before the pest problem becomes a big deal."

To understand how species richness and diversity differed between cropped land and natural field edges, Clem set up dozens of tiny "emergence tents" that capture any insects emerging from the ground in a small area. He put 10 tents in each of five organic soybean fields in Illinois and 10 in nearby field edges in early March, and left them there until late April. Then he collected and analyzed all the arthropods caught in the tents.

Four of the five uncultivated field edges were enrolled in the Conservation Reserve Program, a land conservation initiative administered by the Farm Service Agency of the U.S. Department of Agriculture. The CRP offers financial rewards to farmers who agree to "remove environmentally sensitive land from agricultural production and plant species that will improve environmental health and quality." It is the largest conservation program in the nation, protecting 22 million acres. The field edges in the study were a mixture of grasses and broadleaf plants, including some flowering plants.

Clem collected and identified more than 4,200 potential natural enemies of pests, consisting of 95 species including predatory beetles, true bugs and parasitoid wasps. Overall arthropod diversity and abundance were nearly two times greater in the field edges than in the adjoining fields. However, one site - with a field border made up mostly of mowed grass and less plant diversity than the other sites - had far fewer of these beneficial arthropods, the researchers found.

"We were able to determine that these field edges are important for maintaining natural enemies of pest species in the landscape," Clem said. "And the quality of the field border is likely to benefit the arthropod communities that live there and enhance the services they provide."

"This research supports the idea that these uncropped areas - whether you want to call them field borders, field margins or even ditches - are really beneficial for insects and other arthropods," Harmon-Threatt said. "Preserving some land that is not cultivated and not mowing your field edges might make a big difference for insect conservation, but it's probably also making a difference in controlling pests in farm areas, which is also super-important for meeting our other goals of feeding a growing population."

A team of scientists led by Nanyang Technological University (NTU Singapore) and Rice University in the US, has uncovered the key to the outstanding toughness of hexagonal boron nitride (h-BN). h-BN can withstand ten times the amount of force that graphene can, which is known as one of the toughest materials on Earth.

A two-dimensional (2D) material, h-BN has a thickness of just one atom. First used in cosmetics in the 1940s, it was soon abandoned due to its high price, making a resurgence in the late 1990s after technology made its production cheaper.

Today, it is used by nearly all leading producers of cosmetic products because of its ability to absorb excess facial sebum and disperse pigment evenly, and as a protective layer in 2D electronics, as it insulates against electricity and withstands temperatures of up to 1000 °C.

The NTU and Rice scientists said their new understanding of the compound's unique properties could pave the way to designing new flexible materials for electronics.

When scientists examined h-BN that had been exposed to stress, they saw that any breakages in the material branched like forks in a road, instead of travelling straight through the material (see Image 3), and meaning that fractures in h-BN are less likely to grow when further stress is applied.

Elaborating on the significance of their findings, Professor Gao Huajian, a Distinguished University Profesor in NTU's School of Mechanical and Aerospace Engineering, who led the study, said: "Our experiments show that h-BN is the toughest nanomaterial measured to date. What makes this work so exciting is that it unveils an intrinsic toughening mechanism in this material - which should be brittle as it is only one atom thick. This is unexpected as there is often a trade-off between the strength and brittleness of nanomaterials."

This latest research breakthrough is another of Prof Gao's achievements in the field of applied mechanics. He was recently awarded the prestigious 2021 Timoshenko Medal by the American Society of Mechanical Engineers (ASME)[1] in recognition of his pioneering contributions to nanomechanics of engineering and biological systems, a new research field at the interface of solid mechanics, materials science and biophysics.

Professor Lou Jun, from Rice University's Department of Materials Science and NanoEngineering, who also led the study, said: "In the real world, no material is free from defects, which is why understanding fracture toughness - or resistance to crack growth - is so important in engineering. It describes how much punishment a real-world material can withstand before failing."

The research was published in the top scientific journal Nature in June.

Unveiling the secret behind h-BN's toughness

After 1,000 hours of lab experiments and the use of computer simulations, the scientists traced the vastly different fracture toughness of graphene and h-BN to their chemical compositions.

Like a honeycomb, both h-BN and graphene are arranged in interconnecting hexagons (see Image 3). However, the hexagons in graphene consist solely of carbon atoms, while each hexagon structure in h-BN consists of three nitrogen and three boron atoms.

This difference in composition is what causes a moving crack in h-BN to branch off its path, and this tendency to branch or turn means it takes more energy for a crack to be driven further into it. By contrast, graphene breaks more easily, as fractures travel straight through the material like a zipper.

The researchers say that h-BN's surprising toughness could make it the ideal option for making tear-resistant flexible electronics, such as wearable medical devices and foldable smartphones. It could also be added to strengthen electronics made from two-dimensional (2D) materials, which tend to be brittle.

Besides its flexibility, h-BN's heat resistance and chemical stability would allow it to serve as both a supporting base and an insulating layer between electronic components, setting it apart from other traditional materials used in electronics.

Elaborating on the future applications of their study, Prof Gao said: "Our findings also point to a new route to produce tough materials by adding structural asymmetry into their designs. This would reduce the likelihood of materials fracturing under extreme stress, which may cause the devices to fail and lead to catastrophic effects."

Prof Lou added: "The niche area for 2D material-based electronics like h-BN are in flexible electronic devices. In addition to applications like electronic textiles, 2D electronic devices are thin enough for more exotic applications like electronic tattoos and implants that could be attached directly to the brain."

The scientists are now using their findings to explore new methods to produce tougher materials for mechanical and electronic manufacturing.

Mangrove vegetation, which grows naturally in subtropical shorelines, provides a wide range of ecosystem functions such as reducing coastal erosion, promoting biodiversity, and removing nitrogen, phosphorus and carbon dioxide. These vital ecological functions are influenced by the water flow around the intricate mangrove roots, which create a complex energetic process that mixes up sediments and generates a depositional region behind the roots. How these mangrove roots interact with water flow is believed to be a key element in mitigating coastal erosion.

Accurately projecting hydrodynamic erosion and the essential amount of mangrove species has been a challenge for managers and restoration experts to forecast a successful component of project designs. That is because they need two critical pieces of information: characterization of the near-bed boundary layer of the mangrove roots and their effect on the mangrove root erosion; and a quantitative understanding of mangrove root erosion and the habitat requirements based on the optimal porosity.

Florida Atlantic University's Oscar M. Curet, Ph.D., an associate professor in the Department of Ocean and Mechanical Engineering within the College of Engineering and Computer Science, spearheaded the research with his co-authors, and are the first to quantify the optimal mangrove root hydrodynamic with a predictive model. For the study, published in Scientific Reports, (published by Nature) they used simplified mangrove root-type models with different porosities to investigate the impact of porosity on the initial motion of the sediments, which is critical to the evolution of shorelines, delta and lands. This predictive model takes into account the mangrove roots' porosity and the near-bed turbulence effect.

The study identified the pivotal role of mangrove root porosity and provides insight into the sediment transport and erosion processes that govern the evolution of the shapes of shorelines. The field studies' wide spatiotemporal parameters could extend the results of the current research to successfully predict mangrove erosion outcomes on estuarine shorelines.

"Our data address the first informational need for global restoration communities with mangrove habitats and will bring about opportunities for interdisciplinary collaboration with the environmental and ecological engineering community," said Amirkhosro Kazemi, Ph.D., lead author and a post-doctoral research associate in the Department of Ocean and Mechanical Engineering. "Furthermore, understanding the hydrodynamics and scaling of this problem could contribute to the design and development of a bio-inspired mangrove-like system for coastal protection globally, especially in the subtropical regions where mangrove growth is possible."

Characterizing the hydrodynamics of mangrove-like structures could explain the primary mechanisms for its resilience and by which mangrove roots can withstand high-energy fluid conditions. For example, the researchers observed that most sediments are eroded for the case with high porosity (less blockage), and the sediment deposition region for the low porous patch (φ = 47 percent) had the maximum area among others signifying an optimal porosity to mitigate erosion for a fixed root configuration. This information has the potential to improve future coastal infrastructure design with bio-mimetic mangrove-like structures.

The study also suggests that optimal porosity design of shoreline may add habitat flexibility to sites that are on the borderline of mangrove habitat suitability. This optimal porosity would affect increase in the critical velocity at which the sediment transport starts. The increment in the critical velocity has biological importance as it could potentially increase nutrients around the roots, increase energy dissipation to withstand high flow speeds, and control changes to the substrate bottom to facilitate the propagation of mangrove swamps.

"Roots that do not exceed the critical porosity for maximum energy dissipation may have adaptive benefits, for example, the ability to tolerate brackish waters in depositional environments," said Curet. "Increasing the mangrove species through pre-restoration grading can potentially increase the likelihood of decreasing erosion success, with a higher energy dissipation that increases the resistance of mangrove roots to the energy in tidal flows."

Down the road, Kazemi, Curet and co-author Luciano Castillo, Ph.D., Kenninger Professor of Renewable Energy and Power Systems in Mechanical Engineering, School of Mechanical Engineering, Purdue University, propose using machine learning (ML) algorithms that can be an alternative way to predict the processes of sediment transport in three-dimensional directions under oscillating flow conditions, by utilizing the available dataset of video images and the state-of-the-art deep learning and ML algorithms. With abundant sediment transport data, ML algorithms can find the patterns and structures of the data to produce a viable morphodynamic model. Based on the training dataset, these algorithms can learn, infer and predict physical phenomena that can potentially be utilized in several applications such as flow control, energy harvesting and erosion mitigation.

"This important research by Dr. Kazemi, professor Castillo and Dr. Curet contribute to fill a gap in understanding the near-bed flow and step forward accurate prediction of sediment transport in vegetated regions, which contributes to shaping them in nature," said Stella Batalama, Ph.D., dean, College of Engineering and Computer Science. "The optimal configuration porosity range and the critical velocity presented in this study can provide useful guidance for coastal managers restoring estuarine mangrove forests or planting mangroves as part of living shoreline stabilization."

A team led by UC Riverside engineers has developed a catalyst to remove a dangerous chemical from water on Earth that could also make Martian soil safer for agriculture and help produce oxygen for human Mars explorers.

Perchlorate, a negative ion consisting of one chlorine atom bonded to four oxygen atoms, occurs naturally in some soils on Earth, and is especially abundant in Martian soil. As a powerful oxidizer, perchlorate is also manufactured and used in solid rocket fuel, fireworks, munitions, airbag initiators for vehicles, matches and signal flares. It is a byproduct in some disinfectants and herbicides.

Because of its ubiquity in both soil and industrial goods, perchlorate is a common water contaminant that causes certain thyroid disorders. Perchlorate bioaccumulates in plant tissues and a large amount of perchlorate found in Martian soil could make food grown there unsafe to eat, limiting the potential for human settlements on Mars. Perchlorate in Martian dust could also be hazardous to explorers. Current methods of removing perchlorate from water require either harsh conditions or a multistep enzymatic process to lower the oxidation state of the chlorine element into the harmless chloride ion.

Doctoral student Changxu Ren and Jinyong Liu, an assistant professor of chemical and environmental engineering at UC Riverside's Marlan and Rosemary Bourns College of Engineering, took inspiration from nature to reduce perchlorate in water at ambient pressure and temperature in one simple step.

Ren and Liu noted anaerobic microbes use molybdenum in their enzymes to reduce perchlorate and harvest energy in oxygen-starved environments.

"Previous efforts in constructing a chemical molybdenum catalyst for perchlorate reduction have not been successful," Liu said. "Many other metal catalysts either require harsh conditions or are not compatible with water."

The researchers tried to emulate the complicated microbial perchlorate reduction process with a simplified approach. They found by simply mixing a common fertilizer called sodium molybdate, a common organic ligand called bipyridine to bind the molybdenum, and a common hydrogen-activating catalyst called palladium on carbon, they produced a powerful catalyst that quickly and efficiently broke down the perchlorate in water using hydrogen gas at room temperature with no combustion involved.

"This catalyst is much more active than any other chemical catalyst reported to date and reduces more than 99.99% of the perchlorate into chloride regardless of the initial perchlorate concentration," Ren said.

The new catalyst reduces perchlorate in a wide concentration range, from less than 1 milligram per liter to 10 grams per liter. This makes it suitable for use in various scenarios, including remediating contaminated groundwater, treating heavily contaminated wastewater from explosives manufacturing, and making Mars habitable.

"A convenient catalytic reduction system may help harvest oxygen gas from perchlorate washed from the Martian soil when the catalyst is coupled with other processes," Liu said.

Water is weird - and yet so important. In fact, it is one of the most unusual molecules on Earth. It boils at a temperature it shouldn't. It expands and floats when it is in the solid-state. Its surface tension is higher than it should be. Now, new research published in the journal Nature has added one other equally strange property to water's list of oddities. The implications of this new revelation could have a remarkable impact on all water-related processes from water purification to drug manufacturing.

Stephen Cronin, professor of electrical and computer engineering at USC Viterbi School of Engineering, and Alexander Benderskii, associate professor of chemistry at the USC Dornsife College of Letters, Arts and Sciences, have showed that when water comes into contact with an electrode surface all its molecules do not respond in the same way. This can dramatically affect how well various substances can dissolve in water subject to an electrical field, which in turn, can determine how a chemical reaction will occur. And chemical reactions are a necessary component in how we make...everything.

It's appropriate that this groundbreaking work should come from interdisciplinary research between a chemist and an electrical engineer. After all, chemistry is fundamentally a study of electrons, and chemical reactions are what make the materials our modern world is built on. Each researcher provided an important component to the work. In this case, a groundbreaking electrode from the engineer, Cronin, and an advanced laser spectroscopy technique from the chemist, Benderskii. Ultimately, it was the combination of these two designs that led to the breakthrough observed.

First, Cronin designed a unique electrode built from monolayer graphene (just 0.355nm thick). Building graphene electrodes in and of itself is a very complex process. In fact, the electrode needed for this particular research is one that research groups across the globe have tried and failed to do in the past. "Alex and I had been struggling a while to achieve this and we had to change our design many times. It's rewarding and exciting to finally see the results of our work," Cronin said.

Once the electrode is placed on a cell of water and begins running a current, Benderskii's technique comes into play. He uses a special laser spectroscopy method that only a handful of other research groups have been capable to reproduce. "Using our approach to observe water molecules for the first time under the conditions of our experiments, we were able to see how the molecules interacted with the field in a way no one had previously understood," Benderskii said.

What the two found was that the top layer of water molecules closest to the electrode align in a completely different way than the rest of the water molecules. This realization was unexpected. But it can open the way to run more accurate simulations of how aqueous chemical reactions in various fields affect the materials they work with. One particular area where this research could have an immediate impact is providing clean water. "Water in contact with graphene is indeed being proposed as a new technology in de-salinization," Cronin said. "Our research could help scientists design better simulations that will ultimately bring to people desalinated clean water faster, cheaper, and cleaner."

Benderskii and Cronin don't plan on ending their long-standing research collaboration anytime soon. Now that they have identified this new quality of water, they plan to dig deeper. "Our published research is about how water collectively responds to a current. Next, we are trying to understand how this response works at an individual molecular level," Benderskii said.

A research group from Kobe University has demonstrated that the heat generated by the impact of a small astronomical body could enable aqueous alteration (*1) and organic solid formation to occur on the surface of an asteroid. They achieved this by first conducting high-velocity impact cratering experiments using an asteroid-like target material and measuring the post-impact heat distribution around the resulting crater. From these results, they then established a rule-of-thumb for maximum temperature and the duration of the heating, and developed a heat conduction model from this.

The research group consisted of the following members from Kobe University's Graduate School of Science; Lecturer YASUI Minami, TAZAWA Taku (a 2nd year masters student at the time of research), HASHIMOTO Ryohei (then a 4th year undergraduate in the Faculty of Science) and Professor ARAKAWA Masahiko, in addition to JAXA Space Exploration Center's Associate Senior Researcher OGAWA Kazunori (who was a technical specialist at Kobe University at the time of the study).

These results have expanded the spatial and temporal range over which the necessary conditions for aqueous alteration and organic solid formation could occur. This is expected to significantly increase the number of prospective astronomical bodies that could have brought water and the origins of life to Earth.

These research results were published in the British scientific journal Communications Earth and Environment (Nature Publishing Group) on May 18, 2021.

Main Points

The researchers used porous gypsum as an imitation asteroid and inserted multiple thermocouples (*2) inside it. They conducted high-velocity impact experiments on this target at impact speeds of 1km/s and over, and succeeded in measuring changes in temperature duration around the resulting crater soon after impact.

This revealed that, regardless of the impact speed and projectile's size and density, the maximum temperature and its duration were dependent upon dimensionless distance (the distance from the impact point scaled by the crater radius).

Using the above results, the researchers calculated the temporal changes in thermal heat distribution after the crater's formation on the asteroid's surface. These calculations suggested that, at distances within 2 astronomical units (*3), aqueous alteration can occur if the crater has a radius of over 20km, and organic solid formation can be supported by craters of over 1km.

These findings will enable an increased number of astronomical bodies to be considered as candidates for the source of the water and organic substances necessary for the beginning of life on Earth.

Research Background

It is believed that the water and organic substances necessary for life to begin on Earth were the result of a comet or asteroid impacting the planet. Minerals and organic substances that have experienced aqueous alteration have been discovered in meteorites (from which asteroids originate), providing proof that they once contained water. However, a heat source is necessary for the chemical reactions that cause aqueous alteration and organic solid formation inside asteroids.

One sufficiently strong heat source is the radioactive decay heating of 26Al (aluminum, *5), a short-lived radioactive nuclide found inside rocks. However, it is said that the radioactive heating that caused aqueous alteration and solid formation on asteroid parent bodies (*4) could have only occurred at the beginning of the solar system's history due to the short half-life of 26Al (720,000 years).

In recent years, the theory that the impact heat generated when a small astronomical body hits an asteroid could also be a viable heat source has started to gain attention. However, it is not known how much heat is generated depending on the astronomical body's characteristics (size, density, impact speed) and how far within the asteroid this generated heat is transmitted. Up until now, there have been no studies that have experimentally investigated this heat generation and propagation process to determine whether aqueous alteration and organic substance formation would be possible.

Research Methodology

This research group conducted laboratory experiments to investigate the relationship between the impact heat generated on an asteroid (as a result of a small astronomical body's impact) and the impact's characteristics. For the target, they used gypsum (a porous mineral composed of calcium sulfate dihydrate) to imitate an asteroid. They accelerated projectiles at the target at high impact velocities of between 1km/s to 5km/s using Kobe University's two-stage horizontal gas gun. Multiple thermocouples were set in the gypsum target in order to measure the temperature changes post-impact. In this series of experiments, the researchers changed the size, density, impact speed of the projectiles and the thermocouples' positions in order to investigate the differences in heat duration depending on the characteristics of the impact (Figure 1).

From the heat duration graph, the research group investigated the maximum temperature and its duration, and looked at how this related to the impact characteristics (Figure 2). By using the dimensionless distance obtained by normalizing the distance from the impact point (where the projectile hit the target) by the crater radius, they successfully determined how maximum temperature and its duration are altered by impact characteristics and came up with a rule-of-thumb for this.

Subsequently constructing a heat conduction model incorporating this rule of thumb, enabled them to calculate the heat distribution around the crater formed on the asteroid surface (Figure 3). The research group checked the numerical results from the heat conduction model against data on the required heat and duration for aqueous alteration and organic solid formation obtained from past analyses of meteorites.

These results showed that aqueous alteration could occur if a crater with a radius of over 20km was formed within 2au from the Sun. In addition, they estimated that even a small crater with a 100m radius on an asteroid within 4au could heat up to 100°C, meaning that it could support organic solid formation. Most asteroids are located within 4au. The researchers also found that if a crater with a radius of over 1km is formed within 2au, the circumference of the crater can heat up to 0°C (the temperature at which ice becomes water), thus enabling organic solids to be formed.

Further Developments

It is thought that radioactive decay heating of 26Al triggers the chemical reactions for aqueous alteration and organic solid formation on asteroids. However, this heating can only occur near the core of comparatively large asteroids that are tens of kilometers in diameter. Furthermore, it is said that this could have only occurred within a million years after the Sun's formation due to the short half-life of 26Al. On the other hand, collisions between asteroids still occur today, and it is possible that such collisions heat up the surface of even small asteroids, providing that the impact does not destroy the asteroid itself. In other words, these research results show that the potential for asteroids to support aqueous alteration and organic solid formation is temporarily and spatially far greater than previously thought. This will contribute towards an increased number of astrological bodies being considered as candidates that brought the water and organic substances for the beginning of life on Earth.

Next the research group hopes to examine samples returned from asteroid exploration missions conducted not only by Japan but other countries as well. If aqueously altered minerals or organic substances were to be discovered in the collected samples, this could provide evidence of impact heating's effects.

Atomically thin van der Waals magnets are widely seen as the ultimately compact media for future magnetic data storage and fast data processing. Controlling the magnetic state of these materials in real-time, however, has proven difficult. But now, an international team of researchers led by Delft University of Technology (TU Delft) has managed to use light in order to change the anisotropy of a van der Waals antiferromagnet on demand, paving the way to new, extremely efficient means of data storage.

The thin atomic layers that make up van der Waals magnets may seem extremely fragile, but they can be about 200 times stronger than steel. Unfortunately, this mechanical strength does not necessarily translate into strong magnetic properties. The reason for this is that, in two dimensions, the magnetic order of these magnets becomes especially vulnerable to heat. Any temperature above the absolute zero (-273 °C) activates random fluctuations in the orientation of the microscopic spins, which can completely collapse the magnetic order. So until we can control their magnetic state, the promises of atomically thin magnets are just that: promises.

Controlling magnetism

The only way to counteract the thermal agitations is to stick magnetic spins more to some directions in the material than to others. Or, as physicists call it: to induce 'magnetic anisotropy'. Doing so makes it harder for spins to change their orientation, thereby lifting their ordering temperature (known as the Curie temperature) way above absolute zero. Controlling anisotropy in low-dimensional magnets, in other words, paves a direct pathway to controlling their ordering temperature and thus the magnetism itself.

In their study the international team, which consisted of researchers from The Netherlands, Spain and Ukraine, used ultrashort pulses of light, a trillion times shorter than a single second, to induce the magnetic anisotropy in a two-dimensional van der Waals antiferromagnet. Why use light? "Because it's a very convenient control knob", Dr. Andrea Caviglia explains. "You can simply and swiftly turn it on and off and therefore manipulate the anisotropy on demand, which is exactly what we need if we want to start using these materials for efficient data storage."

Tuning the color

By systematically varying the color of the light from visible to near-infrared, the scientists also found that not every type of light can generate magnetic anisotropy. To induce this property, the color of light needs to match the energy required to change the orbital state of the electron. That is to say: to change the way electron whirls around a positively charged nucleus. As the electron spin and its orbital motion are tightly linked, the light excitations induce anisotropy, which results in a two-dimensional spin-wave motion. "This motion is coherent - the whole spin ensemble moves in-phase at high frequencies", says Jorrit Hortensius, a PhD student at TU Delft. "This is an elegant and at the same time virtually universal solution to manipulating magnetic anisotropy in practically any two-dimensional magnet."

In this proof-of-principle experiment, the team showed that anisotropy can be photoinduced for a tiny fraction of time, nearly the same as the duration of the light pulse. However, for practical applications the changes to the magnet need to be sustained for a longer period of time. The scientists hope that light pulses with a longer-duration might help to reach this goal. Dr. Dmytro Afanasiev, who currently works at University of Regensburg says: "We hope that longer light pulses can even promote the magnetic order above the equilibrium ordering temperature, so that we can watch in real-time how the ordered state arises from magnetic chaos. This will certainly increase our understanding of magnetism in these van der Waals magnets."

The gut and the brain communicate with each other in order to adapt satiety and blood sugar levels during food consumption. The vagus nerve is an important communicator between these two organs. Researchers from the Max Planck Institute for Metabolism Research in Cologne, the Cluster of Excellence for Ageing Research CECAD at the University of Cologne and the University Hospital Cologne now took a closer look at the functions of the different nerve cells in the control centre of the vagus nerve, and discovered something very surprising: although the nerve cells are located in the same control center, they innervate different regions of the gut and also differentially control satiety and blood sugar levels. This discovery could play an important role in the development of future therapeutic strategies against obesity and diabetes.

When we consume food, information about the ingested food is transmitted from the gastrointestinal tract to the brain in order to adapt feelings of hunger and satiety. Based on this information, the brain decides, for example, whether we continue or stop eating. In addition, our blood sugar level are adapted by the brain. The vagus nerve, which extends from the brain all the way down to the gastrointestinal tract, plays an essential role in this communication. In the control center of the vagus nerve, the so-called nodose ganglion, various nerve cells are situated, some of which innervate the stomach while others innervate the intestine. Some of these nerve cells detect mechanical stimuli in the different organs, such as stomach stretch during feeding, while others detect chemical signals, such as nutrients from the food that we consume. But what roles these different nerve cells play in transmitting information from the gut to the brain, and how their activity contributes to adaptations of feeding behavior and blood sugar levels had remained largely unclear.

"To investigate the function of the nerve cells in the nodose ganglion, we developed a genetic approach that enables us to visualize the different nerve cells and manipulate their activity in mice. This allowed us to analyze which nerve cells innervate which organ, pointing to what kind of signals they detect in the gut," says study leader Henning Fenselau. "It also allowed us to specifically switch on and off the different types of nerve cells to analyze their precise function."

Different food activates different nerve cells

In their studies, the researchers focused primarily on two types of nerve cells of the nodose ganglion, which is just one millimeter in size. "One of these cell types detects stomach stretch, and activation of these nerve cells causes mice to eat significantly less," Fenselau explains. "We identified that activity of these nerve cells is key for transmitting appetite-inhibiting signals to the brain and also decreasing blood sugar levels." The second group of nerve cells primarily innervates the intestine. "This group of nerve cells senses chemical signals from our food. However, their activity is not necessary for feeding regulation. Instead, activation of these cells increases our blood sugar level," says Fenselau. Thus, these two types of nerve cells in the control center of the vagus nerve fulfil very different functions.

"The reaction of our brain during food consumption is probably an interplay of these two nerve cell types," Fenselau explains. "Food with a lot of volume stretches our stomach, and activates the nerve cell types innervating this organ. At a certain point, their activation promotes satiety and hence halts further food intake, and at the same time coordinates the adaptations of blood sugar levels. Food with a high nutrient density tends to activate the nerve cells in the intestine. Their activation increases blood glucose levels by coordinating the release of the body's own glucose, but they do not halt further food intake." The discovery of the different functions of these two types of nerve cells could play a crucial role in developing new therapeutic strategies against obesity and diabetes.

Prenuptial agreements, or "prenups," can be difficult to talk about. But a recent study offers insights into how people can discuss this often taboo subject. One approach? Use metaphors.

"Many people view prenups as being negative, and argue that they indicate a lack of faith in the marriage from the outset," says Lynsey Romo, corresponding author of the study and an associate professor of communication at North Carolina State University. "By the same token, we know from other research that open communication about financial issues contributes to successful relationships.

"And yet there is virtually no academic research on prenups. So how do people talk about prenups? How do they make sense of them? That's what we wanted to explore here."

The researchers originally set out to conduct in-depth interviews with people about prenups. However, they struggled to find people who had prenups, or were willing to talk about the fact that they had prenups. So they turned to online discussion site Reddit.

"We found that the semi-anonymous nature of Reddit lends itself to people talking freely about anything, including prenups," Romo says.

The researchers found 586 threads, or conversations, that focused on prenups. These threads consisted of 26,450 comments. The researchers then manually coded all of the comments to place them into different categories for analysis.

Broadly speaking, the researchers found that commenters fell into one of two camps: people who felt prenups were good and people who felt prenups were bad.

Those who felt prenups were bad argued that prenups were antithetical to the idea of marriage as a lifelong institution; that prenups were an exit plan from marriage; or that prenups were an indicator that people already have doubts about their relationships.

As one commenter noted: "You're not even married yet and you're thinking about what happens when you get divorced."

But the researchers were surprised to learn that the majority of commenters felt prenups were beneficial. And this group of commenters used metaphor to capture the ways in which a prenup was a good thing.

For example, many commenters described prenups as "insurance" - preparing for the worst even though you don't think you'll need it. As one commenter noted: "Nobody plans on crashing their car, getting cancer, or having their house burn down but they still get car, health, and home insurance."

Others described prenups as safety features, designed to prevent harm. Here's how one commenter approached the subject: "Getting a car with airbags does not mean you don't also make sure you have good brakes and tires. Smart people do all the above; only crazy people say if you get airbags you're jinxing it or are not committed to making things work."

Still others described marriage as a contract, and that a prenup was simply a logical aspect of that contract. After all, two companies wouldn't merge without clearly defined expectations on every aspect of operations.

"It was clear from following these online dialogues that metaphors served as a powerful tool for helping people not only understand what prenuptial agreements are, but what purposes they serve," Romo says. "Metaphors helped many people reframe and understand other perspectives on prenups, including whether they are inherently problematic.

"From a practical standpoint, this work outlines ways that financial and legal advisors can help their clients understand prenups. And maybe it will encourage people to talk about their finances and what they can do to protect each other."

RUDN University chemists proposed a new way to synthesize catalysts for the conversion of ethyl alcohol. The obtained materials are promising catalysts for the selective conversion of ethanol, which is an important stage in the development of an alternative technology for obtaining valuable chemical synthesis products based on plant raw materials. The results of the study are published in Catalysis Today.

Ethanol fuel is ethyl alcohol, it is produced from plant material by fermentation of industrial or agricultural waste biomass. It is used as a more environmentally friendly fuel compared to gasoline. But this is not its sole use -- ethanol can be converted into acetaldehyde, diethyl ether and other chemicals that are in demand in the industry. Highly efficient catalysts are required to trigger such chemical reactions. However, existing catalysts contain precious metals, and therefore they are too expensive to use. RUDN University chemists proposed new catalysts based on aluminium and zirconium, modified with copper.

"The best-known catalysts for ethanol conversion are based on oxides promoted by noble metals. However, they are quite expensive. A more affordable option is catalysts with copper as the active phase, but so far, the best option has not been found among them. Improvements are required to use these catalysts to ensure both high conversion and selectivity of the reaction -- that is, to leave as little ethanol as possible unprocessed and at the same time to obtain the necessary substances, and not by-products", Anna Zhukova, associated professor, PhD, from the Department of Physical and Colloidal Chemistry of RUDN University

RUDN chemists combined two approaches to improve the efficiency of catalysts for acetaldehyde synthesis. First, they combined oxides of several metals in nanocomposites: aluminium, cerium, and zirconium. The researchers synthesized five types of powders with different oxides ratios. Five of them was prepared at a relatively low temperature of 180°C, and another five was heated to 950°C. This made it possible to form different structures in the materials. The calcined samples had a large diameter and pore volume.

The second idea was to add copper. All the powders were soaked in an aqueous solution of copper nitrate, dried at room temperature, and exposed to a flow of hydrogen at 400°C. After that, the finished catalysts were tested in the ethanol vapor dehydrogenation reaction. Chemists placed them in a thin layer on a porous filter, and then fed alcohol vapors in the helium flow. The reaction was carried out at temperatures from 240°C to 360°C.

"All obtained systems demonstrated ? high alcohol conversion and selectivity to acetaldehyde. The copper containing catalysts with 5% aluminium oxide produced significant amounts of acetaldehyde with selectivity above 80 % at 3600C. We found that the mixed composition of the oxides creates conditions for the formation of active centres on the surface of the catalyst from copper ions with different charges. The best option is to use a mixture of oxides with a small content of aluminium in the synthesis of the catalyst and calcinate them at 950°C", Anna Zhukova from RUDN University

An international team of astrophysicists led by the Stellar Astrophysics Group of the University of Alicante (UA), the Instituto de Astrofísica de Canarias (IAC), and the University of Valparaíso (Chile) has discovered a massive cluster of stars of intermediate age in the direction of the Scutum constellation. This object, which has been named Valparaíso 1, lies some seven thousand light years away from the Sun, and contains at least fifteen thousand stars. To detect it, observations have been combined from ESA's Gaia satellite, and various ground-based telescopes, including the Isaac Newton Telescope at the Roque de los Muchachos Observatory (Garafía, La Palma, Canary Islands). The result has been published in Monthly Notices of the Royal Astronomical Society (MNRAS).

Open clusters are groups of stars which were born together, and move together, bound by gravity. This makes them natural laboratories for studying the physics and the lives of stars. The more stars there are in a cluster, the more useful it is, because the larger sample gives a better chance to find stars in less frequent evolutionary phases.

This is why astronomers are searching for the most massive clusters in our Galaxy, those with over ten thousand stars. Until twenty years ago it was thought that these are formed only in distant galaxies with exotic properties, but thanks to these searches now we know a dozen very young massive clusters (less than 25 million years old), and a few very old ones (thousands of millions of years old), which are descendants of former young clusters. But there are hardly any massive clusters known with intermediate ages, and it was not clear whether these do not exist, or whether they had not yet been found.

The newly discovered cluster, which they have called Valparaíso 1, is at some seven thousand light years from the sun, and contains at least fifteen thousand stars. Its unexpected discovery, in a well-explored part of the sky, suggests than many other massive clusters might be hidden in the very dense star fields, which observers find when looking towards the centre of our Galaxy.

"Valparaíso 1 contains dozens of stars sufficiently bright to be observable through an amateur telescope, but they are lost in the middle of a crowd of stars which don't belong to the cluster, but which are in front of it or behind it, and which disguise the structure of the cluster", explains Ignacio Negueruela, a researcher at the University of Alicante and the first author of the article.

"Previous searches tried to locate open clusters, but Valparaíso 1 does not look like a cluster similar to those which we usually find, and that is why it was not discovered before", says Ricardo Dorda, an IAC researcher who is a co-author of the article.

The cluster was detectable thanks to the Gaia satellite of the European Space Agency (ESA), a space telescope which gives extremely accurate positions and distances of stars quite far away, and with this information we can measure the tiny motions across the sky shown by the stars over the years. Combining all of the information, we can detect clusters as groups of stars, which are at the same distance from us, and move together, groups of stars easier to detect using physics than just by looking at them on the sky. When the researchers had located this cluster, they used telescopes at the Las Campanas Observatory (in Chile) and the Isaac Newton Telescope (INT) at the Roque de los Muchachos Observatory (Garafía, La Palma, Canary Islands) to derive the physical properties of its stars.

They studied the extent to which cirrus clouds caused by aircraft occurred during the global hard lockdown between March and May 2020, and compared the values with those during the same period in previous years. The study was led by Johannes Quaas, Professor of Theoretical Meteorology at Leipzig University, and has now been published in the renowned journal "Environmental Research Letters".

Cirrus clouds, known for their high, wispy strands, contribute to warming the climate. When cirrus clouds occur naturally, large ice crystals form at an altitude of about 36 kilometres, in turn reflecting sunlight back into space - albeit to a small extent. However, they also prevent radiated heat from escaping the atmosphere, and thus have a net heating effect. This is the dominant effect in cirrus clouds.

When the weather conditions are right, condensation trails form behind aircraft. These may persist and spread to form larger cirrus clouds. In this case, their effect on the climate is much greater than that of narrow contrails alone.

The researchers led by Professor Quaas analysed satellite images of clouds in the northern hemisphere, between 27° and 68° North, in the period from March to May 2020. They then compared these with images from the same period in previous years. "Crucially, our studies reveal a clear causal relationship. Since clouds vary considerably depending on the weather, we would not have been able to detect the effects of air traffic in this way under normal circumstances. The period of lockdown due to the COVID-19 pandemic offered a unique opportunity to compare clouds in air traffic corridors at very different traffic levels.

Analysis of the data collected showed that nine per cent fewer cirrus clouds formed during the global lockdown, and that the clouds were also two per cent less dense," said Professor Quaas. "The study clearly demonstrates that aircraft contrails lead to additional cirrus clouds and have an impact on global warming." According to Professor Quaas, the data collected confirmed previous estimates based only on climate models: "Our study may improve the ability to simulate these effects in climate models."

Despite the team's findings, there has still not been enough research into the impact of aviation on global warming. A European research collaboration involving Professor Quaas's research group is currently investigating the precise mechanisms in detail. "The tough global lockdown has been helpful in terms of our research. In order to mitigate or even avoid the warming effect on the climate, flight routes could be adapted in the future to avoid cirrus cloud formation, for example by separating flight corridors," said the Professor of Theoretical Meteorology at Leipzig University.