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NASA-NOAA's Suomi NPP satellite passed over the South China Sea and captured a visible image of Tropical Storm Higos. Higos is headed for landfall in southeastern China.

The Visible Infrared Imaging Radiometer Suite (VIIRS) instrument aboard Suomi NPP provided a visible image of Tropical Storm Higos is it moved in a northwesterly direction and toward a landfall in southeastern China. The VIIRS image revealed deep, persistent convection and developing thunderstorms obscuring a low-level circulation center. The VIIRS image also showed there were bands of thunderstorms wrapping around the northern periphery of the system.

At 11 a.m. EDT (1500 UTC), Tropical Storm Higos had maximum sustained winds near 45 knots (52 mph/83 kph). It was located near latitude 21.3 degrees north and longitude 114.3 degrees east, about 82 nautical miles south-southeast of Hong Kong, China.

The Joint Typhoon Warning Center (JTWC) expects Higos to continue moving west-northwest until landfall. Warm sea surface temperatures and low wind shear will fuel intensification so it expected to peak at 50 knot (58 mph/93 kph) sustained winds before landfall, south of Hong Kong. JTWC noted, "After landfall, the rugged terrain of mainland China, in addition to increasing vertical wind shear (outside winds that blow at different levels of the atmosphere that can weaken a storm), will cause the system to begin dissipating over land and rapidly erode the system to full dissipation over land by 36 hours.

For more than five decades, NASA has used the vantage point of space to understand and explore our home planet, improve lives and safeguard our future. NASA brings together technology, science, and unique global Earth observations to provide societal benefits and strengthen our nation. Advancing knowledge of our home planet contributes directly to America's leadership in space and scientific exploration.

LOS ALAMOS, N.M., Aug. 18, 2020--Combing through historical seismic data, researchers using a machine learning model have unearthed distinct statistical features marking the formative stage of slow-slip ruptures in the earth's crust months before tremor or GPS data detected a slip in the tectonic plates. Given the similarity between slow-slip events and classic earthquakes, these distinct signatures may help geophysicists understand the timing of the devastating faster quakes as well.

"The machine learning model found that, close to the end of the slow slip cycle, a snapshot of the data is imprinted with fundamental information regarding the upcoming failure of the system," said Claudia Hulbert, a computational geophysicist at ENS and the Los Alamos National Laboratory and lead author of the study, published today in Nature Communications. "Our results suggest that slow-slip rupture may well be predictable, and because slow slip events have a lot in common with earthquakes, slow-slip events may provide an easier way to study the fundamental physics of earth rupture."

Slow-slip events are earthquakes that gently rattle the ground for days, months, or even years, do not radiate large-amplitude seismic waves, and often go unnoticed by the average person. The classic quakes most people are familiar with rupture the ground in minutes. In a given area they also happen less frequently, making the bigger quakes harder to study with the data-hungry machine learning techniques.

The team looked at continuous seismic waves covering the period 2009 to 2018 from the Pacific Northwest Seismic Network, which tracks earth movements in the Cascadia region. In this subduction zone, during a slow slip event, the North American plate lurches southwesterly over the Juan de Fuca plate approximately every 14 months. The data set lent itself well to the supervised-machine learning approach developed in laboratory earthquake experiments by the Los Alamos team collaborators and used for this study.

The team computed a number of statistical features linked to signal energy in low-amplitude signals, frequency bands their previous work identified as the most informative about the behavior of the geologic system. The most important feature for predicting slow slip in the Cascadia data is seismic power, which corresponds to seismic energy, in particular frequency bands associated to slow slip events. According to the paper, slow slip often begins with an exponential acceleration on the fault, a force so small it eludes detection by seismic sensors.

"For most events, we can see the signatures of impending rupture from weeks to months before the rupture," Hulbert said. "They are similar enough from one event cycle to the next so that a model trained on past data can recognize the signatures in data from several years later. But it's still an open question whether this holds over long periods of time."

The research team's hypothesis about the signal indicating the formation of a slow-slip event aligns with other recent work by Los Alamos and others detecting small-amplitude foreshocks in California. That work found that foreshocks can be observed in average two weeks before most earthquakes of magnitude greater than 4.

Hulbert and her collaborators' supervised machine learning algorithms train on the seismic features calculated from the first half of the seismic data and attempts to find the best model that maps these features to the time remaining before the next slow slip event. Then they apply it to the second half of data, which it hasn't seen.

The algorithms are transparent, meaning the team can see which features the machine learning uses to predict when the fault would slip. It also allows the researchers to compare these features with those that were most important in laboratory experiments to estimate failure times. These algorithms can be probed to identify which statistical features of the data are important in the model predictions, and why.

"By identifying the important statistical features, we can compare the findings to those from laboratory experiments, which gives us a window into the underlying physics," Hulbert said. "Given the similarities between the statistical features in the data from Cascadia and from laboratory experiments, there appear to be commonalities across the frictional physics underlying slow slip rupture and nucleation. The same causes may scale from the small laboratory system to the vast scale of the Cascadia subduction zone."

The Los Alamos seismology team, led by Paul Johnson, has published several papers in the past few years pioneering the use of machine learning to unpack the physics underlying earthquakes in laboratory experiments and real-world seismic data.

When most people think of cooling, they automatically imagine air conditioning (AC), or cooling the air in a room. But, there is a much more efficient way to cool people, using your body's radiation.

To demonstrate the effect of radiant cooling, Forrest Meggers, assistant professor of architecture and the Andlinger Center for Energy and the Environment, and a team of researchers built a "Cold Tube," in Singapore last year. It was an outdoor pavilion lined with novel insulated radiant panels that held cold water pipes inside. Because your body is constantly exchanging radiation with objects around you, and radiation flows from hot to cool surfaces, the participants who walked through the exhibit shed their radiation toward the panels, similar to what would happen if you stood near a freezer. The participants reported feeling cool, despite the air itself having temperature and humidity levels that would ordinarily feel sweltering. The new research showed that people could feel comfortable in hot and humid outdoor environments using only radiant cooling, which could use far less energy than cooling large volumes of air.

The researchers, collaborating with scholars at the University of British Columbia, University of Berkeley, ETH Zurich in Singapore, and the University of Pennsylvania, published their results August 18 in the Proceedings of the National Academy of Sciences (PNAS).

In this Q&A, Meggers and first author of the paper, Dr. Eric Teitelbaum, now a senior engineer at AIL Research, comment on why this research is so relevant not just in a warming world, but also in a contagious one, where equipping indoor spaces with outdoor levels of air flow is part of the strategy to contain the spread of the COVID-19 virus.

Your recent work published in PNAS showed that people can be kept cool in very hot and humid environments without air conditioning. What is the benefit of cooling surfaces, such as walls and tables, instead of cooling the air? How are the findings relevant to keeping people safe from viruses like COVID-19?

Meggers: Today, around the world, people are trying to achieve higher outdoor air flow indoors to dilute the amount of virus in the air. With air conditioning (AC), dehumidification and cooling occur simultaneously. The benefit of the Cold Tube technology is that it decouples cooling from the providing of fresh air, meaning people can keep their windows open, while maintaining comfort, and without expending massive amounts of energy to cool and dehumidify the air flow.

Teitelbaum: The way buildings are built today, using exclusively AC for cooling, we can't increase the amount of fresh air we deliver to buildings at will because outdoor air flow is coupled with the amount of air conditioning buildings need to provide. If you want more outdoor air flowing into the building, you also need additional capacity to dehumidify and cool that air. Most systems weren't built with the capacity to flow the amount of air that, in many cases, is being recommended to dilute indoor air pollutants and prevent the spread of COVID-19. And if they can, it requires massive amounts of energy.

Meggers: In the Cold Tube, occupants were cooled entirely by thermal radiation, which means energy was primarily used for cooling the water inside the walls, not cooling the air. Through most summer conditions, we could cool people using surfaces, while leaving all the windows open. Achieving 100% outdoor air would do a lot to stymie the spread of the virus, and the efficiency benefits scale proportionally with how much outdoor air you want. Air should be only for breathing, not cooling.

How does this help mitigate climate change?

Teitelbaum: This system uses at least 50% less energy than a comparably-sized air conditioner. Letting the air warm up by five degrees while cooling surfaces, can lower energy demand by up to 40% and maintain occupant comfort. Allowing even hotter air temperatures would result in higher energy savings.

What is the biggest misconception about air conditioning?

Meggers: Air conditioning does not equal cooling. It's a highly engrained method of cooling buildings, but it's not the only one. Additionally, your window air conditioners are just cooling existing air in the room; they don't bring new, fresh air into your room. Air conditioning units have become so normalized and integrated into daily life but, in reality, they are huge machines that require a lot of energy, and should not be treated like turning on a light switch. A seemingly simple window unit requires 10-1000x more energy than a ceiling fan, and leaving the AC on is comparable in energy to leaving the light on in 100 rooms.

In terms of urban planning and outdoor air quality, how does this alternative to air conditioning provide dual-benefits and help mitigate the urban heat island effect?

Meggers: Most of my coauthors and I have traveled around Southeast Asia and have seen firsthand how quickly AC units have been deployed at scale. Adding AC window or split units to buildings is done with little contemplation of the effects on surface temperatures, and the climate and heat in a city. The units work by rejecting the heat from the air in a room to the outside. Rejecting heat outside the buildings, along the façade, leads to sidewalks and areas around buildings becoming very hot, and many spaces becoming unusable. Our technology does exactly the opposite; it provides opportunities to regain thermal acceptability in various parts of the city without having to build a huge park. You can install these cooling panels outside in hot and humid environments, and build "cool havens" where people can gather, eat, and play.

Is there anything else you want to talk about in regards to this paper or today's context for it?

Teitelbaum: It will take more than an 8-month experiment to change the way people think about comfort systems and energy efficiency in the built environment. Much of the C.H.A.O.S lab's research has focused on expanding the knowledge bubble of thermal radiation's influence on comfort and efficiency. The Cold Tube experiment created a lot of new knowledge, which is a great academic success. Commercially, while there are companies that manufacture similar technologies, there is still a need to continue to demonstrate and experiment with new concepts to not only further the technology, but also this paradigm shift. The shift away from air conditioning towards more holistic comfort design would help us act as stewards of the planet as well as our own built environments. In many parts of the world, such as Singapore and other tropical areas that are increasingly seeking ways to condition spaces, significantly more energy goes towards dehumidifying the air than just cooling the air. This is one of the places that we believe our comfort paradigm will have the greatest efficiency increases and impact, since no dehumidification is required for people to feel comfortable.

New research from the CHILD Cohort Study has shed light on the influence of vitamin D supplementation on a baby's developing gut microbiome.

The study, published in the journal Gut Microbes, found that vitamin D supplementation is associated with compositional changes in a baby's microbiome--notably a lower abundance of the bacteria Megamonas--at three months of age.

"Vitamin D plays an important role in early life, supporting bone metabolism and the healthy development of a baby's immune system," said senior author Anita Kozyrskyj, a professor in the Department of Pediatrics at the University of Alberta and a CHILD Cohort Study investigator. "Most infants in North America receive vitamin D, either as a supplement to breastfeeding or as an ingredient in commercial infant formulas, so we wanted to understand the association between vitamin D and the presence or abundance of key bacteria within a baby's intestinal tract."

The researchers examined fecal samples taken during home visits from 1,157 infants who are part of the CHILD Cohort Study--a national study that is following nearly 3,500 Canadian children from before birth to adolescence with the primary goal of discovering the root causes of allergies, asthma, obesity and other chronic diseases.

They found that direct vitamin D supplementation of infants with vitamin D drops was associated with a lower abundance of Megamonas, regardless of how a baby was fed (breastfed or formula fed). "While little is known about Megamonas in infancy, our previous research suggests there may be a link between this bacterium and asthma or respiratory viral infections, so vitamin D may offer additional benefits for childhood health that should be studied further," added Kozyrskyj, also a member of the Women and Children's Health Research Institute.

The researchers also assessed the association between infant and maternal vitamin D supplementation and the presence of Clostridioides difficile (C. difficile) in a baby's gut. "Some infants carry the diarrhea-causing bacterium C. difficile in their guts without any symptoms. However, when the levels of gut bacteria become imbalanced, this particular bacterium can multiply, causing illness and increasing the susceptibility to chronic disease later in childhood," commented first author Kelsea Drall, an MSc graduate from the U of A and an AllerGen trainee.

The study found that nearly 30 per cent of the infants carried C. difficile, but there was a lower incidence of the bacterium among exclusively breastfed infants. However, neither infant supplementation with vitamin D drops nor maternal vitamin D supplementation during pregnancy or after delivery was associated with C. difficile colonization. "Interestingly, maternal consumption of vitamin D-fortified milk was the only factor that reduced the likelihood of C. difficile colonization in infants," added Drall.

According to Kozyrskyj, an infant's gut microbiota undergoes rapid change in early life. Therefore, it is critical to understand the factors associated with microbial communities populating the infant gut during this key developmental period.

"Low vitamin D levels have been associated with respiratory syncytial virus (RSV)--a common lung infection among infants--and more recently, susceptibility to COVID-19 disease," she pointed out. "In the CHILD Cohort Study, we have a unique opportunity to follow our study children as they get older to understand how microbial changes observed as a result of dietary interventions may be associated with later health outcomes such as asthma and viral infections."

New research led by Flinders University PhD candidate Jasmine Petersen examining commercial physical activity apps has found that the social components of these apps hold great potential to increase physical activity engagement.

Sharing physical activity outcomes and progress to app communities and social networking platforms provides the necessary encouragement for people to engage more enthusiastically with their apps.

"Sharing posts and receiving encouragement provides the social support many people need to stay motivated with exercise programs - and this doesn't change across different age groups," says study co-author Dr Ivanka Prichard, from Flinders University's Caring Futures Institute.

The study - Psychological mechanisms underlying the relationship between commercial physical activity app use and physical activity engagement, by Jasmine Petersen, Lucy Lewis, Eva Kemps and Ivanka Prichard - is published in Psychology of Sport and Exercise. (DOI: 10.1016/j.psychsport.2020.101719)

The study examined close to 1300 adults (88% female, aged between 18 and 83 years), over half of whom used a commercial physical activity app (e.g. Fitbit, Garmin, Strava). Results found that more competitive individuals responded best to the apps, engaging in significantly higher levels of physical activity due to the game-like incentives and rewards built into the apps.

Dr Prichard says this suggests that people with a general disposition toward competition may benefit most from using activity apps.

"App users are motivated by both the enjoyment derived from physical activity (intrinsic motivation) and the personal value placed on the outcomes of physical activity (identified regulation), and these combined motivations result in greater engagement in physical activity," says Ms Petersen.

This study shows that the social components of physical activity apps are particularly beneficial in promoting engagement in physical activity due to their capacity to facilitate social support, and positively influence motivation and beliefs in one's ability to perform physical activity.

However, it was also found that online interactions can have a negative effect on exercisers if social networking is used to make direct comparisons.

"Engagement in comparisons was associated with lower self-efficacy and higher external regulation, and in turn, lower physical activity," says Dr Prichard, emphasising the importance of exercising for enjoyment and the benefits that exercise can provide to general health.

The team are now following up participants to see how commercial physical activity apps might support physical activity behaviour in light of COVID-19 restrictions.

Osaka, Japan - Researchers at Osaka University have discovered a new method to easily add lanthanide cubanes into a previously synthesized metallo-supramolecular framework. By simply soaking a crystal in a cubane-containing solution, the molecules become intercalated via a single-crystal-to-single-crystal transformation. This research may help chemists design cost-effective methods of storing energy or develop new catalysts.

Once thought too unstable to exist, cubanes are synthetic molecules with atoms arranged to form a cube. The extremely strained right-angle bonds store a great deal of chemical energy, like tightly wound springs. However, once created by chemists, cubanes can keep their shape for a long time. These properties make cubanes attractive candidates for storing energy, as well as for accelerating reactions as catalysts.

Now, scientists at Osaka University have shown how to immobilize cubanes made from lanthanide elements into crystal frameworks. "We discovered a facile synthetic method for lanthanide hydroxide clusters, which may be used as functional materials," says first author Nobuto Yoshinari.

Lanthanides are a group of chemically similar elements, known to many people for their special section on most versions of the periodic table. The researchers found that by immersing a crystal of K6[Rh4Zn4O(L-cys)12] in a solution containing Ln4(OH)4 (lanthanide hydroxide) cubane molecules, the cubane molecules became attached inside the empty pockets of the crystal without disrupting its structure. A metal-organic framework (MOF) was obtained when using the heavier lanthanides, while the lighter elements yielded ionic solid structures.

"Previously, lanthanide hydroxide clusters have been synthesized under harsh conditions, but our new method requires only the soaking of the host crystals into a lanthanide salt solution at room temperature," senior author Takumi Konno explains.

The team tested the catalytic activity of the frameworks when speeding up a hydrolysis reaction. They found that the effectiveness of the catalyst depended on which element from the lanthanide series was used. The researchers also measured the magnetic susceptibility of the metal ions inside the frameworks, and found a cooling effect when exposed to a decreasing magnetic fields. The lanthanide hydroxide clusters created inside the crystal framework are expected to be useful for a wide range of applications, including materials for magnetic cooling as well as advanced heterogeneous catalysts.

A team of international physicists led by Lia Krusin-Elbaum of the City College of New York, has created a new topological magnetic superlattice material, that at a high temperature can conduct electrical current without dissipation and lost energy. The finding, detailed in a paper published in Nature Physics, could be the basis of research leading to an entire new quantum materials class that can potentially provide a platform for error-free quantum computing.

The material in the form of crystals is created in a laboratory chamber. Atoms, in this process, naturally arrange into well-organized layers - a novel ordered magnetic superlattice - which the City College team tests in the Krusin Lab for quantized electrical transport.

The research centers around the Quantum Anomalous Hall Effect (QAHE), which describes an insulator that conducts dissipationless current in discrete channels on its surfaces. Because QAHE current does not lose energy as it travels, it is akin to a superconducting current and has the potential if industrialized to advance energy-efficient technologies.

"The main advance of this work is that the new higher temperature QAHE regime is robust, eminently tunable through electron irradiation and thermal vacancy redistribution, and can be modified on-demand by adjusting the superlattice sequence, leading to a platform for topological superconductivity," said Krusin-Elbaum, professor in CCNY's Division of Science.

Krusin-Elbaum and her graduate student Haiming Deng said they can advance this platform to other topological magnets. The ultimate goal would be to help transform future quantum electronics with the material. The CCNY-based Harlem Center for Quantum Materials is a partner in the research. It strives to solve fundamental problems in novel functional materials systems that have vital scientific and technological importance.

Irvine, Calif. - University of California, Irvine materials science researchers are learning about resilience from the mantis shrimp. The ancient crustaceans are armed with two hammerlike raptorial appendages called dactyl clubs that they use to bludgeon and smash their prey. These fists, able to accelerate from the body at over 50 mph, deliver powerful blows yet appear undamaged afterward.

The UCI researchers discovered that the clubs have a uniquely designed nanoparticle coating that absorbs and dissipates energy. The findings, published today in Nature Materials, have significant implications for engineered materials in the automotive, aerospace and sports industries.

"Think about punching a wall a couple thousand times at those speeds and not breaking your fist," said David Kisailus, UCI professor of materials science & engineering, who has been studying the mantis shrimp for more than a decade. "That's pretty impressive, and it got us thinking about how this could be."

He and postdoctoral scholar Wei Huang used transmission electron and atomic force microscopy to examine the nanoscale architecture and material components of the clubs' surface layer. They determined that the nanoparticles are bicontinuous spheres, made of intertwined organic (protein and polysaccharide) and inorganic (calcium phosphate) nanocrystals.

The 3D inorganic nanocrystals are mesocrystalline, essentially stacked together like Lego pieces, with small orientational differences where they join together. The crystalline interfaces are crucial to the resilience of the surface layer, because they fracture and break during high-speed impact, decreasing the penetration depth by half.

"The high-resolution TEM really helped us understand these particles, how they're architected and how they react under different types of stress," Kisailus said. "At relatively low strain rates, the particles deform almost like a marshmallow and recover when the stress is relieved."

He noted that the behavior of the structures under high-strain impact is much different. "The particles stiffen and fracture at the nanocrystalline interfaces," Kisailus said. "When you break something, you're opening up new surfaces that dissipate significant amounts of energy."

The team, which included researchers from Purdue University, Oxford Instruments and Bruker Corp., was also able to measure and characterize the impressive damping capabilities of the coating.

"The stiff inorganic and soft organic materials in an interpenetrating network confer impressive damping properties to the coating without compromising stiffness. It's a rare combination that outperforms most metals and technical ceramics," Kisailus said.

He added that he's now focused on translating these findings to new applications in a variety of fields: "We can imagine ways to engineer similar particles to add enhanced protective surfaces for use in automobiles, aircraft, football helmets and body armor."

Imagine if every time you looked at a face, one side of the face always appeared distorted as if it were melting, resembling a painting by Salvador Dalí. This is the case for people who have a rare condition known as hemi-prosopometamophosia (hemi-PMO), which makes looking at faces discomforting. According to a new study published in Current Biology, some people with hemi-PMO see distortions to the same half of a person's face regardless of how the face is viewed. The results demonstrate that our visual system standardizes all the faces we perceive using the same process so they can be better compared to faces we have seen before.

"Every time we see a face, the brain adjusts our representation of that face so its size, viewpoint, and orientation is matched to faces stored in memory, just like computer face recognition systems such as those used by Facebook and Google," explains co-author Brad Duchaine, a professor of psychological and brain sciences and the principal investigator of the Social Perception Lab at Dartmouth College. "By aligning the perceived face with faces stored in memory, it's much easier for us to determine whether the face is one we've seen before," he added.

Hemi-PMO is a rare disorder that may occur after brain damage. When a person with this condition looks at a face, facial features on one side of the face appear distorted. The existence of hemi-PMO suggests the two halves of the face are processed separately. The condition usually dissipates over time, which makes it difficult to study. As a result, little is known about the condition or what it reveals about how human face processing normally works.

The current study focused on a right-handed man in his early sixties ("Patient A.D.") with hemi-PMO whose symptoms have persisted for years. Like many with this condition, his distortions were caused by damage to a fiber bundle called the splenium that connects visual areas in the left hemisphere and right hemisphere of his brain. Five years ago while A.D. was watching television, he noticed that the right halves of people's faces looked like they had melted. Yet, the left sides of their faces looked normal. He looked in the mirror at his own face and noticed that the right side of his reflection was also distorted. In contrast, A.D. sees no distortions in other body parts or objects.

The study involved two experiments. In the first, A.D. was presented with images of human faces and non-face images such as objects, houses and cars, and asked to report on distortions. For 17 of the 20 faces, he saw distortions. The distortions were always on the right side of the face and facial features usually appeared to drooped. For example, in one of the faces, A.D. reported that the right eye looked a lot bigger than the left eye while the right eyebrow, right side of the nose, and right side of the lips all hung down unnaturally. Two of the face photographs that did not elicit a distortion showed right profile views in which the right side of the face was not visible. Consistent with his daily experiences, A.D. did not see distortions in any of the non-face images. These results show that his condition affects brain processes specialized for faces.

For the second part of the study, A.D. reported on distortions that he saw in 15 different faces that were presented in a variety of ways: in the left and right visual field, at different in-depth rotations, and at four picture plane rotations-- 0 degrees or upright, 90 degrees, 180 degrees or upside down, and 270 degrees. Regardless of how the faces were presented, A.D. continued to report that the distortions affected the same facial features. For example, even when a face was presented upside down, A.D. still saw the facial features distorted on the right side of the face even though the distortion now appeared on the left-hand side of the stimulus (the red-shaded region in the faces in the reproduction of Figure 4E below). The consistency of the location of A.D.'s distortion demonstrates that faces, regardless of viewpoint or orientation, are aligned to the same template similar to what computer face recognition systems do. In A.D.'s case, the output from that process is disrupted as it is passed from one brain hemisphere to the other due to his splenium lesion.

In a new study published in Cell Research, Chen-Yu Zhang's group at Nanjing University School of Life Sciences, China, reports that SIDT1 in the mammalian stomach mediates host uptake of dietary and orally administered microRNAs (miRNAs), thus exerting biological functions in the host.

In previous studies, Chen-Yu Zhang's group has demonstrated that intact plant miRNA in foods can be absorbed through the mammalian digestive system and mediate cross-kingdom gene regulation. The discoveries also provide new insight into the oral administration of RNA therapeutic drugs. Although accumulated evidences showing the existence of intact dietary miRNAs within mammalian host, the absorption of dietary miRNAs in animal gastrointestinal tract has been frequently questioned, mainly due to the unknown mechanism of absorption.

In the current study, they show that SID-1 transmembrane family member 1 (SIDT1), mammalian homolog of SID-1 expressed on gastric pit cells in the stomach is required for the absorption of dietary miRNAs. SIDT1-deficient mice show reduced basal levels and impaired dynamic absorption of dietary miRNAs. Notably, they identified the stomach as the primary site for dietary miRNA absorption, which is dramatically attenuated in the stomachs of SIDT1-deficient mice. Mechanistic analyses revealed that the uptake of exogenous miRNAs by gastric pit cells is SIDT1 and low-pH dependent. Furthermore, oral administration of plant-derived miR2911 retards liver fibrosis, and the protective effect was abolished in SIDT1-deficient mice. This study not only reveals the major mechanism of dietary miRNA absorption, uncovers a novel physiological function of the mammalian stomach, but also shed light on orally delivered small-RNA therapeutics.

This work is important for the following reasons:

1. In this study, they demonstrated the molecular mechanism of mammalian dietary miRNA absorption, which is one of the most groundbreaking as well as most controversial discoveries in the field of extracellular RNA research in the last decade. Identification of the absorption mechanism provides strong evidence of the physiological existence and functionality of mammalian dietary miRNA absorption, thus ending the 10-year debate on this topic.
2. This work also newly found that the stomach not only absorbs water and alcohol, as is broadly known in classic physiology, but also senses and takes up functional dietary miRNAs. This provides a unique new understanding of digestion physiology.
3. A low-pH condition is required for efficient exogenous miRNA uptake via SIDT1. This finding reveals an evolutionary explanation for functional dietary miRNA absorption, in which the stability of dietary miRNAs is granted in stomach, where RNase activity is largely absent in this low-physiological-pH gastric environment.
4. By oral administration, plant-derived miR2911 can be absorbed via SIDT1 and can subsequently alleviate liver fibrosis in mice, providing a new therapeutic strategy for small-RNA-based treatment. This natural mammalian absorption pathway of dietary miRNA will be easily harnessed for the oral delivery of therapeutic miRNAs, which could be a potential direction in for the development of RNA-based medicine.

Most of modern medicine has physical tests or objective techniques to define much of what ails us. Yet, there is currently no blood or genetic test, or impartial procedure that can definitively diagnose a mental illness, and certainly none to distinguish between different psychiatric disorders with similar symptoms. Experts at the University of Tokyo are combining machine learning with brain imaging tools to redefine the standard for diagnosing mental illnesses.

"Psychiatrists, including me, often talk about symptoms and behaviors with patients and their teachers, friends and parents. We only meet patients in the hospital or clinic, not out in their daily lives. We have to make medical conclusions using subjective, secondhand information," explained Dr. Shinsuke Koike, M.D., Ph.D., an associate professor at the University of Tokyo and a senior author of the study recently published in Translational Psychiatry.

"Frankly, we need objective measures," said Koike.

Challenge of overlapping symptoms

Other researchers have designed machine learning algorithms to distinguish between those with a mental health condition and nonpatients who volunteer as "controls" for such experiments.

"It's easy to tell who is a patient and who is a control, but it is not so easy to tell the difference between different types of patients," said Koike.

The UTokyo research team says theirs is the first study to differentiate between multiple psychiatric diagnoses, including autism spectrum disorder and schizophrenia. Although depicted very differently in popular culture, scientists have long suspected autism and schizophrenia are somehow linked.

"Autism spectrum disorder patients have a 10-times higher risk of schizophrenia than the general population. Social support is needed for autism, but generally the psychosis of schizophrenia requires medication, so distinguishing between the two conditions or knowing when they co-occur is very important," said Koike.

Computer converts brain images into a world of numbers

A multidisciplinary team of medical and machine learning experts trained their computer algorithm using MRI (magnetic resonance imaging) brain scans of 206 Japanese adults, a combination of patients already diagnosed with autism spectrum disorder or schizophrenia, individuals considered high risk for schizophrenia and those who experienced their first instance of psychosis, as well as neurotypical people with no mental health concerns. All of the volunteers with autism were men, but there was a roughly equal number of male and female volunteers in the other groups.

Machine learning uses statistics to find patterns in large amounts of data. These programs find similarities within groups and differences between groups that occur too often to be easily dismissed as coincidence. This study used six different algorithms to distinguish between the different MRI images of the patient groups.

The algorithm used in this study learned to associate different psychiatric diagnoses with variations in the thickness, surface area or volume of areas of the brain in MRI images. It is not yet known why any physical difference in the brain is often found with a specific mental health condition.

Broadening the thin line between diagnoses

After the training period, the algorithm was tested with brain scans from 43 additional patients. The machine's diagnosis matched the psychiatrists' assessments with high reliability and up to 85 percent accuracy.

Importantly, the machine learning algorithm could distinguish between nonpatients, patients with autism spectrum disorder, and patients with either schizophrenia or schizophrenia risk factors.

Machines help shape the future of psychiatry

The research team notes that the success of distinguishing between the brains of nonpatients and individuals at risk for schizophrenia may reveal that the physical differences in the brain that cause schizophrenia are present even before symptoms arise and then remain consistent over time.

The research team also noted that the thickness of the cerebral cortex, the top 1.5 to 5 centimeters of the brain, was the most useful feature for correctly distinguishing between individuals with autism spectrum disorder, schizophrenia and typical individuals. This unravels an important aspect of the role thickness of the cortex plays in distinguishing between different psychiatric disorders and may direct future studies to understand the causes of mental illness.

Although the research team trained their machine learning algorithm using brain scans from approximately 200 individuals, all of the data were collected between 2010 to 2013 on one MRI machine, which ensured the images were consistent.

"If you take a photo with an iPhone or Android camera phone, the images will be slightly different. MRI machines are also like this - each MRI takes slightly different images, so when designing new machine learning protocols like ours, we use the same MRI machine and the exact same MRI procedure," said Koike.

Now that their machine learning algorithm has proven its value, the researchers plan to begin using larger datasets and hopefully coordinate multisite studies to train the program to work regardless of the MRI differences.

Emerging technologies can be harnessed to use the strengths of hot, humid coastal deserts of the Middle East and North Africa (MENA) region to grow food and other crops.

KAUST researchers are calling for a new generation of vast greenhouse complexes, supported by novel solar panels, air-cooling technologies, and advances in salt-tolerant agriculture. Their concept could kickstart a sustainable agriculture revolution in coastal desert regions across the world.

"Controlled environment agriculture (CEA) uses integrated systems to facilitate sustainable, local crop growth on a large scale," says Kyle Lauersen, synthetic biologist. "Our vision combines several technologies currently in development at KAUST: energy-efficient, transparent solar panels; low-energy desiccant cooling; salt-tolerant edible plants; and algal biotechnology."

Coastal locations in the MENA region have ample access to seawater and year-round intense sunlight. CEA makes it possible to use seawater to use grow salt-tolerant crops, such as newly identified varieties of tomatoes and green vegetables. Mixed irrigation means that CEA would have a lower impact on municipal supplies. To source extra freshwater, the researchers plan to harvest from humid air.

"We are excited by developments in cooling technologies that leverage liquid desiccants," says research scientist Ryan Lefers. "Desiccants are highly concentrated substances that absorb water from the air--think of the silica packs found in electronic packaging. When humid air is pumped through a liquid desiccant system, it uses a highly saline liquid solution to absorb the moisture."

The air released by the system is drier and cooler and can be circulated in the greenhouses, while the captured freshwater is recovered. The buildup of excessive heat inside greenhouses is a major concern in the MENA region. One solution comes from KAUST start-up iyris: which uses semitransparent solar panels as windows. Such panels allow visible light through for plant growth, while converting infrared energy (heat) into electricity.

The researchers also hope to combine plant and algae growth to generate not just food, but also biomass feedstocks for aquaculture, animal feed, chemical industry products and bioplastics. Algae can be grown in photobioreactors inside CEA, and this co-cultivation would increase the system's value output.

"We see incredible potential for regionally inspired mixtures of salt-tolerant and freshwater species in different facilities, depending on market demands," says Lauersen. "It's becoming increasingly important to produce food and products in closer proximity to communities that need it. CEA will also provide food security, jobs and an economic base for year-round exports."

"This is where multidisciplinary research comes into its own," says plant scientist Mark Tester. "A pilot CEA greenhouse is under construction at KAUST as part of our spin-off company Red Sea Farms, and we will collaborate with colleagues across the university and beyond to demonstrate the exciting potential for CEA."

With the increasing miniaturization of electronic components, researchers are struggling with undesirable side effects: In the case of nanometer-scale transistors made of conventional materials such as silicon, quantum effects occur that impair their functionality. One of these quantum effects, for example, is additional leakage currents, i.e. currents that flow "astray" and not via the conductor provided between the source and drain contacts. It is therefore believed that Moore's scaling law, which states that the number of integrated circuits per unit area doubles every 12-18 months, will reach its limits in the near future because of the increasing challenges associated with the miniaturisation of their active components. This ultimately means that the currently manufactured silicon-based transistors -- called FinFETs and equipping almost every supercomputer -- can no longer be made arbitrarily smaller due to quantum effects.

Two-dimensional beacons of hope

However, a new study by researchers at ETH Zurich and EPF Lausanne shows that this problem could be overcome with new two-dimensional (2-D) materials -- or at least that is what the simulations they have carried out on the "Piz Daint" supercomputer suggest.

The research group, led by Mathieu Luisier from the Institute for Integrated Systems (IIS) at ETH Zurich and Nicola Marzari from EPF Lausanne, used the research results that Marzari and his team had already achieved as the basis for their new simulations: Back in 2018, 14 years after the discovery of graphene first made it clear that two-dimensional materials could be produced, they used complex simulations on "Piz Daint" to sift through a pool of more than 100,000 materials; they extracted 1,825 promising components from which 2-D layers of material could be obtained.

The researchers selected 100 candidates from these more than 1,800 materials, each of which consists of a monolayer of atoms and could be suitable for the construction of ultra-scaled field-effect transistors (FETs). They have now investigated their properties under the "ab initio" microscope. In other words, they used the CSCS supercomputer "Piz Daint" to first determine the atomic structure of these materials using density functional theory (DFT). They then combined these calculations with a so-called Quantum Transport solver to simulate the electron and hole current flows through the virtually generated transistors. The Quantum Transport Simulator used was developed by Luisier together with another ETH research team, and the underlying method was awarded the Gordon Bell Prize in 2019.

Finding the optimal 2-D candidate

The decisive factor for the transistor's viability is whether the current can be optimally controlled by one or several gate contact(s). Thanks to the ultra-thin nature of 2-D materials -- usually thinner than a nanometer -- a single gate contact can modulate the flow of electrons and hole currents, thus completely switching a transistor on and off.

Structure of a single-gate FET with a channel made of a 2-D material. Arranged around it are a selection of 2-D materials that have been investigated. (Mathieu Luisier/ETH Zürich)

"Although all 2-D materials have this property, not all of them lend themselves to logic applications," Luisier emphasizes, "only those that have a large enough band gap between the valence band and conduction band." Materials with a suitable band gap prevent so-called tunnel effects of the electrons and thus the leakage currents caused by them. It is precisely these materials that the researchers were looking for in their simulations.

Their aim was to find 2-D materials that can supply a current greater than 3 milliamperes per micrometre, both as n-type transistors (electron transport) and as p-type transistors (hole transport), and whose channel length can be as small as 5 nanometres without impairing the switching behaviour. "Only when these conditions are met can transistors based on two-dimensional materials surpass conventional Si FinFETs," says Luisier.

The ball is now in the experimental researchers' court

Taking these aspects into account, the researchers identified 13 possible 2-D materials with which future transistors could be built and which could also enable the continuation of Moore's scaling law. Some of these materials are already known, for example black phosphorus or HfS2, but Luisier emphasizes that others are completely new -- compounds such as Ag2N6 or O6Sb4.

"We have created one of the largest databases of transistor materials thanks to our simulations. With these results, we hope to motivate experimentalists working with 2-D materials to exfoliate new crystals and create next-generation logic switches," says the ETH professor. The research groups led by Luisier and Marzari work closely together at the National Centre of Competence in Research (NCCR) MARVEL and have now published their latest joint results in the journal ACS Nano. They are confident that transistors based on these new materials could replace those made of silicon or of the currently popular transition metal dichalcogenides.

A research team from the University Hospital at Ruhr-Universität Bochum (RUB) has developed a test that provides information on the immune response to the novel coronavirus in patients who need to take immunosuppressive drugs. This is necessary, for instance, following an organ transplantation. "We were able to show that these patients can achieve a good immune response to Sars-Cov-2 despite immunosuppression," says Professor Nina Babel, Head of the Centre for Translational Medicine at Marien Hospital Herne. Immunosuppressive therapy can be adapted individually during a Covid-19 infection using the test. The researchers report in the American Journal of Transplantation on 10 August 2020.

Risk for organ transplant patients twice as high

Chronically ill patients with impaired immune defences have an increased risk of suffering from a severe Covid-19 infection. Transplant patients are affected in several ways: in addition to the chronic illness that led to organ failure and subsequent transplantation, transplant patients need to take medications that suppress the defences of their own immune system.

"These immunosuppressants are necessary to prevent the body from rejecting transplanted organs. However, they can lead to an abundance of viral infections," explains Nina Babel, who, together with Professor Timm Westhoff, Director of Medical Clinic I at Marien Hospital Herne, led the team, including researchers from the Department of Molecular and Medical Virology at RUB and the Surgical Clinic at Knappschaftskrankenhauses Langendreer. "Until now, it has not been known whether our transplant patients are capable of forming a sufficient immune response to the new coronavirus," emphasises Timm Westhoff.

Immune response despite suppressing drugs

With the help of the test established in the Marien Hospital's immunodiagnostics laboratory, the team demonstrated that transplant patients are very capable of achieving a good immune response despite immunosuppression. In addition to high antibody titres, large quantities of T lymphocytes, which are responsible for killing infected cells, were found in the current case study.

The test is of great clinical relevance for transplant patients: the information provided by this goes far beyond a pure antibody test. "The data obtained help us to deal with immunosuppression during the current pandemic," emphasises Timm Westhoff. "The test allows us to individually adjust immunosuppression when a patient is suffering from Covid-19."

In an aging society, one of the most important and urgent tasks of scientific research is to counteract the decline in motor function and muscle weakness that accompanies the aging process.

A research group led by Professor Yuji Yamanashi of the Institute of Medical Science, the University of Tokyo, conducted experiments using aged mice to demonstrate that muscle denervation at the neuromuscular junction (NMJ, *1) could be appreciably offset by an NMJ formation-enhancing treatment that strengthened the motor function and muscle of aged mice.

The results of this study suggest that NMJ formation-enhancing treatment may be effective to overcome motor impairment and muscle weakness associated with human aging.

The results of this research were published in iScience on August 5, 2020.

The NMJ is the only "bond" that connects motor nerves to skeletal muscles

In order to move the body, precise control of skeletal muscle contraction via motor nerves is required. The NMJ is the only "bond" that connects motor nerves to skeletal muscles (the neuromuscular synapse), and its loss means that motor functions including breathing cease to work.

The research group focused on "nerve detachment" aka "denervation" at NMJs, in which the motor nerve becomes separated from the NMJ, a process that progresses with aging.

As a result of the treatment given to aged mice to enhance the formation of NMJs, the following three points were verified:

1) The motor nerve connection was enhanced.

2) Stronger response of skeletal muscle to motor nerve stimulation was observed.

3) Motor function and muscle strength were enhanced in treated mice.

According to the research group, muscle denervation at the neuromuscular junction (NMJ), the essential synapse between motor neuron and skeletal muscle, is associated with age-related motor impairment. Therefore, improving muscle innervation at aged NMJs may be an effective therapeutic strategy for treating the impairment.

They previously demonstrated that the muscle protein Dok-7 (*2) plays an essential role in NMJ formation, and, indeed, its forced expression in muscle enlarges NMJs. Moreover, therapeutic administration of an adeno-associated virus vector encoding human Dok-7 (DOK7 gene therapy) suppressed muscle denervation and enhanced motor activity in a mouse model of amyotrophic lateral sclerosis (ALS). Here, they show that DOK7 gene therapy significantly enhances motor function and muscle strength together with NMJ innervation in aged mice.

Furthermore, the treated mice showed greatly increased compound muscle action potential (CMAP) amplitudes compared to the controls, suggesting enhanced NMJ transmission. Thus, therapies aimed at enhancing NMJ innervation have potential for treating age-related motor impairment.

For details of the research, please see the paper.

Possibility of opening the way to NMJ formation-enhancing therapy using compounds

Yuji Yamanashi, the corresponding author of this research, Professor at the Institute of Medical Science, The University of Tokyo, said, "In this new study with mice, NMJ augmentation treatment was shown to be effective for age-related motor impairment and muscle weakness, which are serious problems in an aging society. It has great social significance in terms of presenting the possibilities."

In addition, this study is not only a basic study of gene therapy using AAV-D7 (*3), but also serves as a proof of principle for opening the way to NMJ formation-enhancing therapy using compounds.

The research group hopes that the findings of this research will be used in the future to promote many research efforts from various perspectives, such as translational research to overcome age-related motor impairment and muscular weakness, together with development of compounds with NMJ formation-enhancing effect.