Tech

NASA's Aqua satellite provided an infrared view of Tropical Storm Lowell that revealed the effects of outside winds battering the storm.

Wind shear occurs when winds at different levels of the atmosphere push against the rotating cylinder of winds, weakening the rotation by pushing it apart at different levels.

NASA's Aqua Satellite Reveals Effects of Wind Shear 

Infrared light is a tool used to analyze the strength of storms in tropical cyclones by providing temperature information about a system's clouds. The strongest thunderstorms that reach highest into the atmosphere have the coldest cloud top temperatures. This temperature information can also tell forecasters if the strongest storms in a tropical cyclone are pushed away from the center, indicating wind shear.

On Sept. 25 at 5:45 a.m. EDT (0945 UTC), the Moderate Resolution Imaging Spectroradiometer or MODIS instrument that flies aboard NASA's Aqua satellite gathered infrared data on Lowell that confirmed wind shear was adversely affecting the storm. Westerly vertical wind shear pushed strongest storms east of the center where cloud top temperatures are as cold as minus 50 degrees Fahrenheit (minus 45.5 Celsius). That small area of strongest storms was located 100 nautical miles east of Lowell's center.

NOAA's National Hurricane Center noted in their discussion today, "The areal coverage of Lowell's convection and its distance from the center already put it on the margins of what is considered organized deep convection."

Status of Tropical Storm Lowell  

At 5 a.m. EDT (0900 UTC), the center of Tropical Storm Lowell was located near latitude 21.6 degrees north and longitude 128.0 degrees west. That is about 1,160 miles (1,865 km) west of the southern tip of Baja California, Mexico. Lowell was moving toward the west near 12 mph (19 kph), and this general motion, with some increase in forward speed, is expected to continue into early next week.

Maximum sustained winds are near 40 mph (65 kph) with higher gusts. Gradual weakening is forecast, and Lowell is expected to become a remnant low today, Sept. 25.

Forecast for Lowell

"Cold waters and increasing west-to-southwesterly wind shear expected over the next 24 hours should finally do the convection in," noted Robbie Berg, a hurricane specialist at NOAA's National Hurricane Center in Miami, Fla. That should cause Lowell to lose tropical cyclone status on Friday. "Even stronger [wind] shear is forecast to cause the remnant low to gradually weaken through the end of the 5-day forecast period."

NASA Researches Tropical Cyclones

Hurricanes/tropical cyclones are the most powerful weather events on Earth. NASA's expertise in space and scientific exploration contributes to essential services provided to the American people by other federal agencies, such as hurricane weather forecasting.

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.

For updated forecasts. visit: http://www.nhc.noaa.gov

By Rob Gutro
NASA's Goddard Space Flight Center

NASA's Terra satellite obtained visible imagery of Post-Tropical Cyclone Beta as it continued moving slowly through the Tennessee Valley. Clouds associated with the low-pressure area looked like a large white blanket draped across much of the southeastern U.S.

On Sept. 25, NOAA's National Weather Service Weather Prediction Center (WPC) in College Park, Md. noted Beta was moving slowly northeast. It was centered about 60 miles (100 km) north-northeast of Birmingham, Alabama.

A NASA Satellite View

The Moderate Resolution Imaging Spectroradiometer or MODIS instrument that flies aboard NASA's Terra satellite captured a visible image of Post Tropical Storm Beta moving slowly through the Tennessee Valley on Sept. 24 and the center of the storm did not move much by Sept. 25. The MODIS image revealed a blanket of clouds associated with Beta stretched from Mississippi to the Carolinas.

The Valley is the drainage basin of the Tennessee River and is largely within the state of Tennessee. It extends from southwestern Kentucky to north Georgia and from northeast Mississippi to the mountains of North Carolina and Virginia.

Satellite imagery was created using NASA's Worldview product at NASA's Goddard Space Flight Center in Greenbelt, Md.

Beta's Status on Sept. 25

On Sept. 25, Beta's center had become less determinant in the pressure and wind fields. In addition, the heavy rainfall threat with Beta has diminished.

At 5 a.m. EDT (0900 UTC) on Sept. 25, NOAA's WPC issued the last public advisory issued on this system. At that time, the center of Post-Tropical Cyclone Beta was located near latitude 34.3 degrees north and longitude 86.3 degrees west. The post-tropical cyclone was moving toward the northeast near 10 mph (17 kph) until it becomes indistinguishable within the background wind and pressure field by mid-afternoon Friday. Maximum sustained winds are near 10 mph (20 kph) with higher gusts.

WPC forecasts rainfall totals of 1 to 3 inches expected through Friday from the southern Appalachians into the Piedmont of South and North Carolina. Isolated flash, urban, and small stream flooding is possible.

About NASA's Worldview and Terra Satellite

NASA's Earth Observing System Data and Information System (EOSDIS) Worldview application provides the capability to interactively browse over 700 global, full-resolution satellite imagery layers and then download the underlying data. Many of the available imagery layers are updated within three hours of observation, essentially showing the entire Earth as it looks "right now."

NASA's Terra satellite is one in a fleet of NASA satellites that provide data for hurricane research.

Hurricanes/tropical cyclones are the most powerful weather events on Earth. NASA's expertise in space and scientific exploration contributes to essential services provided to the American people by other federal agencies, such as hurricane weather forecasting.

For local weather forecasts, visit: http://www.weather.gov

By Rob Gutro
NASA's Goddard Space Flight Center

How many "listeners" a nerve cell has in the brain is strictly regulated. This is shown by an international study led by the University College London and the universities of Bonn, Bordeaux and Milton Keynes (England). In the environment of learning neurons, certain processes are set in motion that make signal transmission less exclusive. The results have now been published in the journal Neuron.

If you want to share a secret with a friend in a busy environment, you may try to find a quiet spot, close the doors and shield the conversation from possible eavesdroppers. Nerve cells in the brain also communicate with each other behind closed doors. But the extent of this protection could be strictly regulated depending on the situation. The findings now presented by the international research team point in this direction.

The information transfer between neurons is mostly done chemically: In response to an electrical signal, the "transmitting cell" releases a so-called neurotransmitter at a synapse; this may often be glutamate molecules. These migrate through the synaptic cleft to the recipient cell. There, they dock to certain receptors and generate an electrical reaction in the receiving neuron.

But the nerve cells in the brain are packed very densely. There is therefore a danger that the molecules not only reach the neuron for which they are intended, but also stimulate other neurons in the neighborhood. This is where the "closed doors" come into play: Specialized cells in the brain, the astrocytes, rapidly reabsorb the glutamate. This way they shield communication to a certain extent. "They do this by sending extensions near synapses, the so-called perisynaptic astrocyte processes or PAPs," explains Prof. Dr. Christian Henneberger from the Institute of Cellular Neurosciences at the University of Bonn.

Molecular glutamate vacuum cleaners

PAPs have specialized transporters that remove the glutamate around the synapses, like small vacuum cleaners. The effectiveness of this mechanism is apparently strictly regulated: The researchers triggered a kind of cellular learning through a repeated electrical stimulation. This causes the receiver cell to respond more strongly to the signals of the transmitting cell in the long term. Experts also speak of "long-term potentiation" (LTP).

"We have now been able to demonstrate that PAPs retreat during this learning process," explains Prof. Dr. Dmitri Rusakov from the Institute of Neurology at University College London. "This increases the likelihood that neighboring cells are also stimulated by the glutamate release." This means that signal transmission also becomes less exclusive, which could explain other interesting observations where the cause was previously unclear: For example, LTP can also affect close connections between other nerve cells. "This may be important for later learning processes," Henneberger suspects.

Large synapses are less discreet

Some synapses also seem to be inherently less discreet than others. Together with his colleague Dr. Michel Herde and other researchers, Henneberger was able to show this in a study published a few days ago in "Cell Reports". The transmitter cell often releases its glutamate into the synaptic cleft at certain structures, the so-called spines. These are tiny extensions of the downstream receiving nerve cell. The PAPs often cover these spines almost like a glove. However, the larger a spine is, the patchier is this coating and the more glutamate can escape. "In the vicinity of large and strong synapses, other nerve cells are therefore probably excited more frequently," says Herde. In other words: Nerve cells with strong synaptic connections rarely speak behind closed doors.

The PhytoFrontiers™ editorial board, led by editor-in-chief Nik Grünwald and associate editor-in-chief Steve Klosterman, is pleased to announce the publication of its first paper, "Distinct Arabidopsis responses to two generalist caterpillar species differing in host breadth," which comes from Jacquie Bede's lab at McGill University in Quebec, Canada.

"Zhang and colleagues provide characterization of biochemical and genetic defenses in the plant in response to generalist caterpillars and those specialist caterpillars with a narrow range," said Klosterman. "PhytoFrontiers seeks to publish a broad range of plant health topics and enthusiastically welcomes studies which contribute to the understanding of plant defense responses to herbivory."

Launched midyear, the broad scope PhytoFrontiers is an interdisciplinary gold open access journal that publishes high quality research covering basic to applied aspects of plant health.

"Research on plant-insect interactions at the molecular and biochemical level has much in common with research published on plant-pathogen interactions in APS journals, such as MPMI," Dr Bede said. "I was excited to publish in PhytoFrontiers as it is a gold-standard open access journal."

Describing her background as diverse and non-linear, Jacquie studied biochemistry at the University of Calgary and gained exposure to medicinal plants and their specialized metabolites while working at a health food store in Toronto. From there, she combined her passion for plants and insects by earning a MSc degree in Botany and a PhD in Zoology from the University of Toronto.

Now in the Department of Plant Science at McGill University in Quebec, Jacquie's research centers around plant-insect interactions.

"Plant-insect interactions represents such fascinating, dynamic multi-trophic interaction; in my lab, we try to tackle this with an understanding from both the insect's and the plant's perspectives," Dr. Bede said. "In particular, we are fascinated by strategies used by caterpillars to undermine plant defenses. The paradigm is that specialist caterpillars are able to cope with defensive specialized metabolites specifically found in their host plants whereas generalist caterpillars have strategies, such as interfering with phytohormone pathways that lead to induced plant defense by activating antagonistic pathways, that allow them to cope with a broad host range of plants that produce a diversity of different defensive compounds."

In their PhytoFrontiers article, Jacquie and colleagues, including first author Zhihong Zhang, who just completed her MSc studies and is interested in the regulation of plant responses to caterpillar herbivory, compare plant responses to two noctuid caterpillar species that are both considered to be "generalist" caterpillars. They investigated differences in plant defense responses from phytohormones to gene expression to specialized metabolites.

The research focused on plant responses to caterpillars of the cabbage looper, Trichoplusia ni, that feeds on different plants but prefers Brassicaceous plants such as Arabidopsis thaliana, and the beet armyworm, Spodoptera exigua, that feeds on plants in more than 30 different families. A. thaliana has distinct responses to these two caterpillar species. In response to beet armyworm herbivory, the plant activates the salicylic acid/NPR1 pathway that interferes with jasmonate-responsive pathway. In response to cabbage looper attack, A. thaliana did not increase its levels of glucosinolate defensive compounds, suggesting that it also manages to subvert induced plant defenses.

"These differences may reflect distinct effectors in the caterpillar labial saliva," explained Dr. Bede. "Beet armyworm labial saliva contains glucose oxidase, which generates the signaling molecule hydrogen peroxide, whereas cabbage looper saliva contains catalase, which decomposes hydrogen peroxide."

Editor-in-chief Nik Grünwald said "we are excited to publish this study from the Bede lab on Arabidposis-caterpillar interactions. We are particularly intrigued by the new twist that caterpillar species-specific, plant-induced responses might reflect differences in oral secretions of caterpillar effectors."

HOUSTON - (Sept. 24, 2020) - Stripes are in fashion this season at a Rice University lab, where researchers use them to make images that plain cameras could never capture.

Their compact Hyperspectral Stripe Projector (HSP) is a step toward a new method to collect the spatial and spectral information required for self-driving cars, machine vision, crop monitoring, surface wear and corrosion detection and other applications.

"I can envision this technology in the hands of a farmer, or on a drone, to look at a field and see not only the nutrients and water content of plants but also, because of the 3D aspect, the height of the crops," said Kevin Kelly, an associate professor of electrical and computer engineering at Rice's Brown School of Engineering. "Or perhaps it can look at a painting and see the surface colors and texture in detail, but with near-infrared also see underneath to the canvas."

Kelly's lab could enable 3D spectroscopy on the fly with a system that combines the HSP, a monochrome sensor array and sophisticated programming to give users a more complete picture of an object's shape and composition.

"We're getting four-dimensional information from an image, three spatial and one spectral, in real time," Kelly said. "Other people use multiple modulators and thus require bright light sources to accomplish this, but we found we could do it with a light source of normal brightness and some clever optics."

The work by Kelly, lead author and Rice alumna Yibo Xu and graduate student Anthony Giljum is detailed in an open-access paper in Optics Express.

HSP takes a cue from portable 3D imaging techniques that are already in consumers' hands -- think of face ID systems in smartphones and body trackers in gaming systems -- and adds a way to pull broad spectral data from every pixel captured. This compressed data is reconstructed into a 3D map with spectral information that can incorporate hundreds of colors and be used to reveal not only the shape of an object but also its material composition.

"Regular RGB (red, green, blue) cameras basically give you only three spectral channels," Xu said. "But a hyperspectral camera gives us spectra in many, many channels. We can capture red at around 700 nanometers and blue at around 400 nanometers, but we can also have bandwidths at every few nanometers or less between. That gives us fine spectral resolution and a fuller understanding of the scene.

"HSP simultaneously encodes the depth and hyperspectral measurements in a very simple and efficient way, allowing the use of a monochrome camera instead of an expensive hyperspectral camera as typically used in similar systems," said Xu, who earned her doctorate at Rice in 2019 and is now a machine learning and computer vision research engineer at Samsung Research America Inc. She developed both the hardware and reconstruction software as part of her thesis in Kelly's lab.

HSP uses an off-the-shelf digital micromirror device (DMD) to project patterned stripes that look something like colorful bar codes onto a surface. Sending the white-light projection through a diffraction grating separates the overlapping patterns into colors.

Each color is reflected back to the monochrome camera, which assigns a numerical grey level to that pixel.

Each pixel can have multiple levels, one for every color stripe it reflects. These are recombined into an overall spectral value for that part of the object.

"We use a single DMD and a single grating in HSP," Xu said. "The novel optical design of folding the light path back to the same diffraction grating and lens is what makes it really compact. The single DMD allows us to keep the light we want and throw away the rest."

These finely tuned spectra can reach beyond visible light. What they reflect back to the sensor as multiplexed fine-band spectra can be used to identify the material's chemical composition.

At the same time, distortions in the pattern are reconstructed into 3D point clouds, essentially a picture of the target, but with a lot more data than a plain snapshot could provide.

Kelly envisions HSP built into car headlights that can see the difference between an object and a person. "It could never get confused between a green dress and a green plant, because everything has its own spectral signature," he said.

Kelly believes the lab will eventually incorporate ideas from Rice's groundbreaking single-pixel camera to further reduce the size of the device and adapt it for compressive video capture as well.

The National Science Foundation funded the research.

Topology-optimized thermal cloak-concentrator realizes excellent cloaking and concentrating simultaneously although it is built of a simple composition. The thermal cloak-concentrator is not so easily effected by fluctuations of thermal conductivity and is designed by incorporating multiple objective functions under various thermal conductivities.

Garuda Fujii of Shinshu University succeeded in simplifying cloaking with the use of topology optimization. In previous studies, metamaterials, which are artificial structures were used to achieve two functions, such as cloaking and concentrating. However, metamaterials make it difficult to manufacture and performance is not easily improved because the performance estimation becomes approximate.

Previous studies investigated the use of general bulk materials, however, it is difficult to achieve multifunctionality and the studies look at just cloaking or concentrating only. By using topology optimization, which is a computational structural design methodology, researchers can use general bulk materials and realize multifunctionality.

The study looked at cloaking the concentrating system in thermal conduction and concentrating heat flux using general materials such as iron, copper, and PDMS. To create STL data of the optimized structures for future experimental demonstrations, they used a structural expression method that can handle the boundaries between different materials clearly and numerically, so called level set-boundary expression. The STL data is publicly available for those who would like to experiment with it.

This study relied on simulations, Associate Professor Fujii hopes to realize this performance in an experiment.

The white, fluffy layer that covers Camembert is made of a mould resulting from human selection, similar to the way dogs were domesticated from wolves. A collaboration involving French scientists from the CNRS* has shown, through genomic analyses and laboratory experiments, that the mould Penicillium camemberti is the result of a domestication process that took place in several stages. According to their work, a first domestication event resulted in the blue-green mould P. biforme, which is used, for example, for making fresh goat's cheese. A second, more recent domestication event resulted in the white and fluffy P. camemberti. Both domesticated species show advantageous characteristics for maturing cheese compared to the wild, closely related species: they are whiter and grow faster in cheese-ripening cellar conditions. In addition, they do not produce, or only in very small quantities, a toxin that is potentially dangerous to humans; they also prevent the proliferation of undesirable moulds. This research, published on 24th September in Current Biology, may have an impact on cheese production, by steering the selection of moulds according to the desired characteristics.

The temporal evolution of the universe, from the Big Bang to the present, is described by Einstein's field equations of general relativity. However, there are still a number of open questions about cosmological dynamics, whose origins lie in supposed discrepancies between theory and observation. One of these open questions is: Why is the universe in its present state so homogeneous on large scales?

From the Big Bang to the present

It is assumed that the universe was in an extreme state shortly after the Big Bang, characterized in particular by strong fluctuations in the curvature of spacetime. During the long process of expansion, the universe then evolved towards its present state, which is homogeneous and isotropic on large scales - in simple terms: the cosmos looks the same everywhere. This is inferred, among other things, from the measurement of the so-called background radiation, which appears highly uniform in every direction of observation. This homogeneity is surprising in that even two regions of the universe that were causally decoupled from each other - i.e., they could not exchange information - still exhibit identical values of background radiation.

Alternative theories

To resolve this supposed contradiction, the so-called inflation theory was developed, which postulates a phase of extremely rapid expansion immediately after the Big Bang, which in turn can explain the homogeneity in the background radiation.

However, how this phase can be explained in the context of Einstein's theory requires a number of modifications of the theory, which seem artificial and cannot be verified directly.

New findings: Homogenization by gravitation

Up to now it was not clear whether the homogenization of the universe can be explained completely by Einstein's equations. The reason for this is the complexity of the equations and the associated difficulty to analyze their solutions - models for the universe - and to predict their behavior.

In the concrete problem, the time evolution of the originally strong deviations from the homogeneous state as cosmological gravitational waves has to be analyzed mathematically. It has to be shown that they decay in the course of the expansion thus allowing the universe to get its homogeneous structure.

Such analyses are based on modern mathematical methods in the field of geometric analysis. Until now, these methods could only achieve such results for small deviations from the homogeneous space-time geometry. David Fajman from the University of Vienna has now succeeded for the first time to transfer these methods to the case of arbitrarily large deviations.

A new research result from Aarhus University shows that a so-called circular RNA molecule, which has been designated as carcinogenic, is actually not found in the cancer cells. The results have just been published in Nature Communications.

In a major surprise, researchers from Aarhus University have discovered that an otherwise extensively studied carcinogenic RNA molecule is not found in the cancerous cells at all. Instead, they suggest that the molecule contributes to the cancer developing through what is known as the microenvironment which constitutes the cancerous cells' 'neighbourhood', i.e. the cells which lie in the environment around the cancer cells in a tumour.

RNA molecules are normally linear and help to ensure that the right proteins are formed in the cells.

"Now we know that certain RNA molecules can, popularly speaking, also bite their own tails and form closed rings, and this gives them completely new properties in the cells," says Lasse Sommer Kristensen from Aarhus University, who is behind the study.

The circular RNA molecule studied by the researchers is called ciRS-7.

Checking the neighbourhood

According to Lasse Sommer Kristensen, an important step in understanding the carcinogenic properties of molecules is to map where these molecules are located in the tumour and which types of cell they are found in.

He predicts that these new results will move the research field in a completely new direction and increase focus on understanding how the molecules work through the microenvironment of the cancer cells.

"We've recently witnessed an explosion of research activity within this new research area, but with our study we show that the conclusions reached by many of the first studies of ciRS-7 are probably premature, primarily due to a lack of spatial analyses," says the researcher.

"We see that other benign cell types in a tumour express very high levels of CiRS-7, which means that the molecule may instead contribute to cancer development through the microenvironment."

More spatial analyses

According to the researchers, when trying to understand the molecular mechanisms that contribute to the development of cancer, it is important to look at cancer as a complex interaction between the cancer cells and the many other types of benign cell types which are found in a tumour.

"In other words, the classic cancer cell lines that are grown in the laboratory and often used to try and understand new molecular mechanisms, don't always give us an accurate view of what is in play in an actual tumour," says Lasse Sommer Kristensen.

He emphasises that the results are therefore a good example of how spatial analyses of patient tumours can contribute with important knowledge that would not have been gained by analysing all RNA from a tumour in a single analysis.

The researchers are now continuing their work towards understanding why ciRS-7 is expressed at a very high level in the tumour's benign cells and whether this molecule contributes directly to the development of cancer through the microenvironment.

Researchers at the University of East Anglia have been putting virtual reality rehabilitation for stroke survivors to the test.

They have created a new gaming platform which uses low cost videogame technology to improve the lives of stroke patients suffering from complex neurological syndromes caused by their stroke.

And they have been working with stroke survivors and their carers to see how they get on with using the new technology.

It is hoped that this type of technology, which can be used in patients' own homes, could prove particularly beneficial for rehabilitation during periods of lockdown, social distancing and shielding - caused by the Covid-19 pandemic.

There are 1.2 million stroke survivors in the UK and around 20-40 per cent of them suffer a debilitating disorder called 'hemispatial neglect'. The condition leaves people unaware of things located on one side of their body and greatly reduces their ability to live independently.

A new study published today is the first to explore the usability of virtual reality games for helping stroke patients recover from this condition.

Lead researcher Dr Stephanie Rossit, from UEA's School of Psychology, said: "A stroke can damage the brain, so that it no longer receives information about the space around one side of the world. If this happens, people may not be aware of anything on one side, usually the same side they also lost their movement. This is called hemispatial neglect.

"These people tend to have very poor recovery and are left with long-term disability. Patients with this condition tell us that it is terrifying. They bump into things, they're scared to use a wheelchair, so it really is very severe and life-changing."

"Current rehabilitation treatments involve different types of visual and physical coordination tasks and cognitive exercises - many of which are paper and pen based.

"We have pioneered new non-immersive VR technology which updates these paper and pen tasks for the digital age - using videogame technology instead.

"But we know that adherence is key to recovery - so we wanted to know more about how people who have had strokes get on with using the new technology."

The team tested out three new games on stroke survivors, their carers and stroke clinicians (including an occupational therapist, healthcare assistant, physiotherapist and clinical psychologist) to better understand how user-friendly the technology is.

The specially designed games included a boxing game where the player spars with a virtual partner, 'Bullseyes and Barriers' where the player hits or avoids targets and 'In the Kitchen' which sees the player search for objects in a realistic kitchen layout.

They also tested a game which involves lifting rods on a table while a portable low cost motion sensor tracks the patient's movements. These balancing exercises are targeted to improve spatial neglect.

The UEA researchers worked with industry collaborator Evolv to create the games, which aim to improve rehabilitation by including elements such as scoring and rewards to engage the patient and improve adherence to their treatment.

David Fried, CEO of Evolv, said: "Traditional rehabilitation treatment is quite monotonous and boring, so this gamification aspect is really important to help people stick with their treatment.

"Our goal is to use technology to make rehabilitation fun and engaging and we have applied this to our Spatial Neglect therapy solution. The great thing about it is that it can be used not only in clinics but also in patients' homes, thereby giving them access to personalised rehabilitation without leaving their living room."

The research team carried out a series of focus groups, questionnaires and interviews to check things like whether the instructions were clear and if the technology was easy enough to use. This is important because gathering feedback from end-users during the development stages is critical to enhance future use and adherence.

Helen Morse, also from UEA's School of Psychology, said: "Overall we found that the end-users were really positive and interested in using virtual reality games to help their special neglect. The participants particularly liked the competition elements and performance feedback like cheers and clapping in the games, and we hope that this will help increase engagement with rehabilitation.

"But some of the older participants found that their lack of experience with technology could be a potential barrier to using the new gaming platform," she added.

"We have used all the feedback we gathered to fine-tune our rehabilitation therapy for spatial neglect called 'c-SIGHT' which involves lifting and balancing rods. With competitive funding from the Stroke Association we are now running a clinical trial in the east of England to test the feasibility of this tool in people's own homes.

"Being able to carry out this type of rehabilitation at home is really important because it means patients can do rehabilitation without a therapist present. This is particularly critical right now because of the Covid-19 pandemic and the need for social distancing and shielding."

Dr Rossit said: "This technology has the potential to improve both independence and quality of life of stroke survivors. We also anticipate other benefits such as improved cost-effectiveness of stroke rehabilitation for the NHS.

"This innovative therapy could also improve long-term care after stroke by providing a low-cost enjoyable therapy that can be self-administered anywhere and anytime, without the need for a therapist to be present on every occasion."

Scientists at Tokyo Institute of Technology (Tokyo Tech) shed light on the relationship between the magnetic properties of topological insulators and their electronic band structure. Their experimental results shed new insights into recent debates regarding the evolution of the band structure with temperature in these materials, which exhibit unusual quantum phenomena and are envisioned to be crucial in next-generation electronics, spintronics, and quantum computers.

Topological insulators have the peculiar property of being electrically conductive on the surface but insulating on their interior. This seemingly simple, unique characteristic allows these materials to host of a plethora of exotic quantum phenomena that would be useful for quantum computers, spintronics, and advanced optoelectronic systems.

To unlock some of the unusual quantum properties, however, it is necessary to induce magnetism in topological insulators. In other words, some sort of 'order' in how electrons in the material align with respect to each other needs to be achieved. In 2017, a novel method to achieve this feat was proposed. Termed "magnetic extension," the technique involves inserting a monolayer of a magnetic material into the topmost layer of the topological insulator, which circumvents the problems caused by other available methods like doping with magnetic impurities.

Unfortunately, the use of magnetic extension led to complex questions and conflicting answers regarding the electronic band structure of the resulting materials, which dictates the possible energy levels of electrons and ultimately determines the material's conducting properties. Topological insulators are known to exhibit what is known as a "Dirac cone (DC)" in their electronic band structure that resembles two cones facing each other. In theory, the DC is ungapped for ordinary topological insulators, but becomes gapped by inducing magnetism. However, the scientific community has not agreed on the correlation between the gap between the two cone tips and the magnetic characteristics of the material experimentally.

In a recent effort to settle this matter, scientists from multiple universities and research institutes carried out a collaborative study led by Assoc Prof Toru Hirahara from Tokyo Tech, Japan. They fabricated magnetic topological structures by depositing Mn and Te on Bi2Te3, a well-studied topological insulator. The scientists theorized that extra Mn layers would interact more strongly with Bi2Te3 and that emerging magnetic properties could be ascribed to changes in the DC gap, as Hirahara explains: "We hoped that strong interlayer magnetic interactions would lead to a situation where the correspondence between the magnetic properties and the DC gap were clear-cut compared with previous studies."

By examining the electronic band structures and photoemission characteristics of the samples (see Figure 1), they demonstrated how the DC gap progressively closes as temperature increases. Additionally, they analyzed the atomic structure of their samples and found two possible configurations, MnBi2Te4/Bi2Te3 and Mn4Bi2Te7/Bi2Te3 (see Figure 2), the latter of which is responsible for the DC gap.

However, a peculiarly puzzling finding was that the temperature at which the DC gap closes is well over the critical temperature (TC), above which materials lose their permanent magnetic ordering. This is in stark contrast with previous studies that indicated that the DC gap can still be open at a temperature higher than the TC of the material without closing. On this note, Hirahara remarks: "Our results show, for the first time, that the loss of long-range magnetic order above the TC and the DC gap closing are not correlated."

Though further efforts will be needed to clarify the relationship between the nature of the DC gap and magnetic properties, this study is a step in the right direction. Hopefully, a deeper understanding of these quantum phenomena will help us reap the power of topological insulators for next-generation electronics and quantum computing.

COLUMBUS, Ohio - Scientists are planning for Phase 1 human trials of a vaccine they developed by using CRISPR gene-editing technology to mutate the parasite that causes leishmaniasis, a skin disease common in tropical regions of the world and gaining ground in the United States.

In a series of animal studies, the vaccine protected mice against the disease - including mice with compromised immune systems and mice exposed to the parasite in the same way humans are, through the bite of infected sand flies.

"If you assure protection in the sand fly model, then you have a good shot at a real vaccine," said Abhay Satoskar, a co-lead investigator of the work and professor of pathology and microbiology at The Ohio State University.

The team applied the new technology to the century-old Middle Eastern practice of leishmanization - deliberately introducing the live parasite to the skin to create a small infection that, once healed, leads to life-long immunity against further disease.

"Live vaccines like that are the best vaccines, but there's a potential risk of causing serious disease in some people," Satoskar said. "We refined the concept using modern technology, making a parasite that does not cause clinical disease but allows for induction of immunity."

The research was published recently in Nature Communications.

An estimated 1.5 million new cases of cutaneous leishmaniasis, caused by the Leishmania major parasite, are diagnosed worldwide each year, primarily in tropical and subtropical regions of the world - but also in southern Texas.

Leishmania in all of its forms is considered a neglected disease, mostly affecting populations in warm-weather developing countries - currently infecting about 12 million in all. But Satoskar noted that with global warming, it's only a matter of time until the southern United States is considered a subtropical region.

"As the warmth moves up toward the United States, the disease will move up," he said.

The standard treatment of more severe cases can be expensive, require multiple daily drug injections and cause unpleasant side effects, leading to poor patient compliance that allows parasites to develop resistance to the drugs.

To develop the vaccine, the researchers set out to use CRISPR to edit the genome of Leishmania major. The precision technology enabled the researchers to delete centrin, the gene for a protein that supports the parasite's physical structure, as well as remove an antibiotic resistance marker gene that is needed to be introduced into the parasite for removal of the centrin gene.

To cause infection, these parasites hijack immune cells and use those host cells to replicate indefinitely. The study showed that the mutant parasite lacking centrin can still find its way into cells and make copies of itself, but for only a limited amount of time and not at a pace that leads to clinical disease.

"So we're essentially using leishmanization. CRISPR allowed us to do that," Satoskar said. "The parasites are unable to proliferate, so they die. But they persist in the body for eight or nine months, which is long enough to generate acquired immunity."

Numerous studies in mice, including immune-deficient animals, showed the mutant parasites did not cause skin lesions, but natural parasites did. In additional experiments, vaccinated and unvaccinated mice were subjected to injections of live parasites and bites from infected sand flies seven weeks after their shots. Ten weeks later, most non-immunized mice developed large skin lesions, but only one vaccinated mouse developed a visible lesion.

"The multiple animal tests also made sure the genome didn't revert back to normal," Satoskar said. "And we found that if a sand fly were to bite at the site of the vaccine and take mutated parasites into the wild, the parasites cannot survive. So it is environmentally safe."

The international team of researchers from the United States, Japan, Canada and India is identifying partners to manufacture the vaccine, aiming to begin a Phase 1 clinical trial within two years. Satoskar said the vaccine is likely to cost less than $5 a dose - compared to the $100 to $200 cost for treatment in the hardest-hit countries.

A much more severe form of the disease, visceral leishmaniasis, affects organs and is fatal if left untreated. The team has been using the same CRISPR technique to mutate the genome of the Leishmania donovani strain that causes visceral leishmaniasis, and preliminary data suggest a safe vaccine could be on the horizon.

Scientists have created a cellular and molecular map of the healthy human heart, to understand how this vital organ functions, and to shed light on what goes wrong in cardiovascular disease.

Researchers from the Wellcome Sanger Institute, Max Delbruck Center for Molecular Medicine (MDC), Germany, Harvard Medical School, Imperial College London and their global collaborators analysed almost half a million individual cells to build a first extensive draft cell atlas of the human heart. The atlas shows the huge diversity of cells and reveals heart muscle cell types, cardiac protective immune cells, and the intricate network of blood vessels. It also predicts how the cells communicate to keep the heart working.

Published today in Nature (September 24th), this study is part of the Human Cell Atlas initiative to map every cell type in the human body. The new molecular and cellular knowledge of the heart will enable better understanding of heart disease and guide more personalised medicine. It could also potentially lead to regenerative medicine in the future.

The heart is an essential organ that pumps blood around the body, enabling oxygen and nutrients to be delivered and carbon dioxide and waste products to be carried away from other vital organs and tissues. Each day, the heart beats around 100,000 times with a one-way flow through 4 different chambers, varying speed with rest, exercise and stress. This is extremely complex and needs the cells in each part of the heart to coordinate with each other for every heartbeat.

Cardiovascular disease is the leading cause of death worldwide, killing an estimated 17.9 million people each year, with heart attacks and strokes causing the majority of these. To understand what happens during heart disease and create better therapeutic strategies, it is vital to know the intricate molecular processes in the cells of the healthy heart.

In this new study, researchers studied nearly 500,000 individual cells and cell nuclei from six different regions of healthy hearts from 14 organ donors*. Using cutting edge, single cell technology, machine learning and imaging techniques, the team could see exactly which genes were switched on in each cell.

The researchers discovered that there were major differences in the cells in different areas of the heart, and that each area of the heart had specific sets of cells, highlighting different developmental origins and potentially different responses to treatments.

Dr Carlos Talavera-Lopez, one of the first authors from the Wellcome Sanger Institute, and previously at the EMBL European Bioinformatics Institute, said: "We have created the most detailed atlas of the human adult heart to date combining single cell technologies with artificial intelligence methods, to characterise almost half a million single cells. For the first time, we could see exactly what each cell is doing in the human heart. This atlas shows that the cells in each of the four chambers of the heart behave differently to each other, mirroring the different functions of each area and helping us understand the healthy human heart."

The six areas of the heart contained 11 different cell types and the researchers discovered more than 62 different cell states, which had never been seen before in this detail.

Professor Norbert Hubner, a senior author from Max Delbruck Center for Molecular Medicine, Charite - Universitatsmedizin Berlin, the Berlin Institute of Health and Deutsches Zentrum fur Herz-Kreislauf-Forschung, Germany, said: "This is the first time anyone has looked at the single cells of the human heart at this scale, which has only become possible with large-scale single cell sequencing. This study shows the power of single-cell genomics and international collaboration. Knowledge of the full range of cardiac cells and their gene activity is a fundamental necessity to understand how the heart functions and start to unravel how it responds to stress and disease."

As part of this study, the researchers studied the blood vessels running through the heart in unprecedented detail. The atlas showed how the cells in these veins and arteries are adapted to the different pressures and locations, and could help understand what goes wrong in the blood vessels during coronary heart disease.

Dr Michela Noseda, a senior author from the National Heart and Lung Institute, Imperial College London, said: "Our international effort provides an invaluable set of information to the scientific community by illuminating the cellular and molecular details of cardiac cells that work together to pump blood around the body. We mapped the cardiac cells that can be potentially infected by SARS-CoV-2 and found that specialized cells of the small blood vessels are also virus targets. Our datasets are a goldmine of information to understand subtleties of heart disease."

Professor Christine Seidman, a senior author from Brigham and Women's Hospital, Harvard Medical School and Howard Hughes Medical Institute, said: "Millions of people are undergoing treatments for cardiovascular diseases. Understanding the healthy heart will help us understand interactions between cell types and cell states that can allow lifelong function and how these differ in diseases. Ultimately, these fundamental insights may suggest specific targets that can lead to individualised therapies in the future, creating personalized medicines for heart disease and improving the effectiveness of treatments for each patient."

The researchers also focused on understanding cardiac repair, looking at how the immune cells interact and communicate with other cells in the healthy heart, and how this differs from skeletal muscle. Further research will include investigating if any heart cells could be induced to repair themselves.

Dr Sarah Teichmann, a senior author from the Wellcome Sanger Institute and co-chair of the Human Cell Atlas Organising Committee, said: "This great collaborative effort is part of the global Human Cell Atlas initiative to create a 'Google-map' of the human body. Openly available to researchers worldwide, the Heart Cell Atlas is a fantastic resource, which will lead to new understanding of heart health and disease, new treatments and potentially even finding ways of regenerating damaged heart tissue."

Self-erasing chips developed at the University of Michigan could help stop counterfeit electronics or provide alerts if sensitive shipments are tampered with.

They rely on a new material that temporarily stores energy, changing the color of the light it emits. It self-erases in a matter of days, or it can be erased on demand with a flash of blue light.

"It's very hard to detect whether a device has been tampered with. It may operate normally, but it may be doing more than it should, sending information to a third party," said Parag Deotare, assistant professor of electrical engineering and computer science.

With a self-erasing bar code printed on the chip inside the device, the owner could get a hint if someone had opened it to secretly install a listening device. Or a bar code could be written and placed on integrated circuit chips or circuit boards, for instance, to prove that they hadn't been opened or replaced on their journeys. Likewise, if the lifespan of the bar codes was extended, they could be written into devices as hardware analogues of software authorization keys.

The self-erasing chips are built from a three-atom-thick layer of semiconductor laid atop a thin film of molecules based on azobenzenes--a kind of molecule that shrinks in reaction to UV light. Those molecules tug on the semiconductor in turn, causing it to emit slightly longer wavelengths of light.

To read the message, you have to be looking at it with the right kind of light. Che-Hsuan Cheng, a doctoral student in material science and engineering in Deotare's group and the first author on the study in Advanced Optical Materials, is most interested in its application as self-erasing invisible ink for sending secret messages.

The stretched azobenzene naturally gives up its stored energy over the course of about seven days in the dark--a time that can be shortened with exposure to heat and light, or lengthened if stored in a cold, dark place. Whatever was written on the chip, be it an authentication bar code or a secret message, would disappear when the azobenzene stopped stretching the semiconductor. Alternatively, it can be erased all at once with a flash of blue light. Once erased, the chip can record a new message or bar code.

The semiconductor itself is a "beyond graphene" material, said Deotare, as it has many similarities with the Nobel Prize-winning nanomaterial. But it can also do something graphene can't: It emits light in particular frequencies.

The research team included the group of Jinsang Kim, professor of material science and engineering. Da Seul Yang, a doctoral student in macromolecular science and engineering, designed and made the molecules. Cheng then floated a single layer of the molecules on water and dipped a silicon wafer into the water to coat it with the molecules.

Then, the chip went to Deotare's lab to be layered with the semiconductor. Using the "Scotch tape" method, Cheng essentially put sticky tape on a chunk of the semiconductor, tungsten diselenide, and used it to draw off single layers of the material: a sandwich of a single layer of tungsten atoms between two layers of selenium atoms. He used a kind of stamp to transfer the semiconductor onto the azobenzene-coated chip.

Next steps for the research include extending the amount of time that the material can keep the message intact for use as an anti-counterfeit measure.

HOUSTON -- A new data analysis tool developed by researchers at The University of Texas MD Anderson Cancer Center incorporates a user-friendly, natural-language interface to allow biomedical researchers without specialized expertise in bioinformatics or programming languages to conduct intuitive analysis of large datasets.

The open-access, artificial intelligence (AI)-driven program, called DrBioRight, was created to lower barriers for all researchers to make full use of the increasingly large amounts of data generated in modern research methods. A report of this platform was published today in Cancer Cell.

"We felt that we could improve the current model for conducting routine bioinformatics analysis and greatly speed up turnaround time by creating a tool that any researcher could use," said Han Liang, Ph.D., professor of Bioinformatics and Computational Biology. "Our long-term goal for DrBioRight is to be an intelligent collaborator for every researcher."

High-throughput technologies used in modern biomedical research generate large, complex datasets that provide comprehensive information about patients, animal models or cell lines being studied. These may include, for example, studying the whole of genetic information (genomics), gene expression (transcriptomics), or protein expression (proteomics).

Because these "omics" datasets are so complex, it can be challenging to answer specific biological questions without specialized analytical approaches, explained Liang. These analyses are usually done with using a computer script written in a variety of programming languages, which requires some understanding of both programming and bioinformatics.

Bioinformaticians can help to navigate and process these complex datasets, but the work can be time consuming. Therefore, the research team developed DrBioRight to enable researchers to more easily conduct routine analyses of their own data through a user-friendly chat interface with natural-language interactions.

The natural language-oriented program allows users to ask questions of the program as if they were speaking naturally rather than in complex programming languages, explained Liang.

DrBioRight is freely available to academic researchers. Initially, the program has a number of modules ready-built to handle the most common types of bioinformatics questions and includes some of most frequently used public cancer datasets available, such as The Cancer Genome Atlas and Cancer Cell Line Encyclopedia.

As a confirmation of the approach, the researchers replicated the analysis of a classic cancer genomics paper using DrBioRight and found it to accurately reproduce the previously published results.

Because the program is driven by AI, it also has the ability to learn from each inquiry and improve analysis, becoming a more useful tool over time. Going forward, the researchers hope to improve DrBioRight to enable users to analyze their own datasets as well as allow open development for new modules.

"As we work to improve the program, we also want to enable other bioinformaticians to contribute their algorithms and teach DrBioRight," said Liang. "Involvement from the entire research community will help to create a tool that is useful in answering complex research questions more efficiently."