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The small Kuiper Belt object (486958) Arrokoth, encountered by NASA's New Horizons spacecraft on Jan 1 2019, is so far the most distant and most primitive object ever explored by a spacecraft. The discoveries from the mission have provided detailed information on the object's shape, geology, color and composition, which help people to reshape the knowledge and understanding of planetesimal origin and planet formation.

The revealed shape of Arrokoth, which is bilobed with highly flattened lobes both aligned to its equatorial plane, is regarded to be the biggest surprise of the flyby. The contact binary is believed to be merged gently by two separate bodies that formed close together and at low velocity, orbited each other. On the other hand, how the flattened lobes formed is still under investigation.

An international research team led by Assoc. Prof. ZHAO Yuhui from the Purple Mountain Observatory (PMO) of the Chinese Academy of Sciences has built and applied a mass-loss-driven shape evolution model (MONET) and suggested that the current flattened shape of Arrokoth could be of evolutionary origin due to volatile outgassing in a timescale of about 1-100 Myr, which provides a natural explanation for the flattening shape of the body.

The study was published in Nature Astronomy on Oct. 5.

A Science publication led by Dr. Will Grundy from Lowell Observatory suggested an early sublimation history of Arrokoth. During the formation of the solar system, the region where Arrrokoth locates could have been a distinct environment in the cold, dust-shaded midplane of the outer nebula. The low temperatures enabled volatile such as CO and CH4 freeze onto dust grains and compose planetesimals. When the nebular dust cleared after Arrokoth's formation, solar illumination would have raised its temperature and hence rapidly driven off the condensed CO and CH4.

Will the sublimation induced mass loss process change the shape of the body, and how?

The researchers from the PMO and Max Planck Institute for Solar System Research in Germany, started to investigate this topic in 2018, not specifically for (486958) Arrokoth, but for all the small icy bodies in our Solar System. It took three years to develop the numerical tools (MONET model), analyze the observational data from space missions, such as the Rosetta mission of ESA, and investigate how solar driven mass loss shape the global structure as well as local topography of small bodies.

Their research suggested that even weak solar driven mass loss rates play an important role in shape evolution of a small icy bodies when sustained over long periods, and the evolved shape highly depends on the configuration of the body's orbit and spin states.

Starting from the merger of a spherical planetesimal and an oblate one, the flattening of Arrokoth's shape is a natural outcome due to a favourable combination of its large obliquity, small eccentricity and mass-loss rate variation with solar flux, resulting in nearly symmetric erosion between north and south hemispheres.

Due to the orientation of Arrokoth, both polar regions experience continuous solar illumination during polar days (with strong mass loss), while the equatorial regions are dominated by diurnal variations year round. Therefore, the polar regions reach higher peak temperatures than the equator and experience more sublimation than the equatorial regions, and hence lead to the flattening.

The flattening process most likely occurred early in the evolution history of the body, and could proceed rather quickly, in a timescale of about 1-100 Myr, during the presence of super volatile ices in the near subsurface layers.

In addition, the researchers self-consistently demonstrated that the induced torques would play a negligible role in the planetestimal's spin state change during the mass loss phase.

This study suggested that sublimation mass loss could be a ubiquitous process and dominant in shaping the structure of Kuiper Belt Objects (KBOs), granted that there were no catastrophic collision reshaping the body in their later history. Furthermore, while cold classical KBOs reserve their shape sculptured by early outgassing, the structure of Centaurs and Jupiter Family Comets (JFCs) would be further modified by the same scenario once they enter their current orbit configuration from the Kuiper Belt, under sublimation of different volatile species.

The Covid-19 pandemic has challenged all facets of human endeavours, and seven months later the economic effects are particularly being felt

How the world can leverage the positive and negative effects of COVID-19 to build a new, more resilient and low-carbon economy has been analysed by a group of academics led by WMG, University of Warwick

A more sustainable model based on circular economy framework could help the world recover financially from COVID-19, whilst facilitating the attainment of net zero carbon goals

The World's economy is feeling the effects of the COVID-19 pandemic with many industries under threat. A group of researchers from the UK, Malaysia, Nigeria, UAE and Japan, led by WMG, University of Warwick have concluded that adopting circular economy strategies would be the best way for the world's economy to recover, whilst enabling the transition to a low-carbon economy.Dr Taofeeq Ibn-Mohammed

The World Health Organisation declared the COVID-19 pandemic on the 11th March 2020, which saw global supply chains severely disrupted and strained, and the financial market unsettled, resulting in a cross-border economic disaster. Lockdowns and border closures shattered the core sustaining pillars of modern world economies, with the economic shock due to these measures still being weighed across the globe.

In the paper, 'A critical analysis of the impacts of COVID-19 on the global economy and ecosystems and opportunities for circular economy strategies', published in the journal Resources, Conservation & Recycling sees a group of researchers led by WMG, at the University of Warwick, critically analysed the negative and positive impacts of the pandemic. To make the world resilient post-COVID-19, the adoption of circular economy framework is recommended for all sectors.

The pandemic had many effects on everyone's lives, from not leaving the house, being infected and possibly hospitalised, and even losing a loved one. It has had a strain on those who were furloughed or even lost their jobs, and the mental health of the populace. Economically, the effects can be felt everywhere due to the colossal financial loss across both the macro and micro levels of the economy, including the global supply chains and international trade, tourism and aviation and many other sectors, hampering the attainment of the United Nations Sustainable Development Goals. However, the pandemic has provoked some natural changes in behaviour and attitudes with positive influences on human health and the planet including:

Improvements of air quality, in fact in the UK it's thought more lives have been saved by the reduced air pollutants compared to the number of people who died with COVID-19 in China, for example.

Reduction in environmental noise and traffic congestions has led to an increase in the number of people exercising outside to enjoy the atmosphere.

Less tourism induced by the pandemic, resulting in less exploitation of the beaches, leading to increased cleanliness.

Decline in global primary energy use. For instance coal use was down 8%, 60% less oil, and electricity plummeted by 20% compared to the first quarter of 2019, leading to record low global CO2 emissions.

Triggering the need for diversification and circularity of supply chains, and evinced the power of public policy for tackling urgent socio-economic crises.

The researchers have examined the impacts of the pandemic and its interplay with circular economy, to evaluate how it could be embraced to rebuild the world's economy.

Dr Taofeeq Ibn-Mohammed, from WMG, University of Warwick comments:

"The pandemic has highlighted the environmental folly of 'extract, produce, use and dump' economic model of material and energy flows, however the short term resolutions to cope with pandemic will not be sustainable in the long-run, as they do not reflect improvements in economic structures of the global economy.

"We therefore propose circular economy adoptions for all industries, with different strategies for each one. For example, embracing the transformative capabilities of digital technologies for supply chain resilience by leveraging: big data analytics for streamlining supplier selection processes; cloud computing to facilitate and manage supplier relationships; and Internet of Things for enhancing logistics and shipping processes.

"The post-COVID-19 investments needed to accelerate towards more resilient, low carbon and circular economies should also be integrated into the stimulus packages for economic recovery being promised by governments, since the shortcomings in the dominant linear economic model are now recognised and the gaps to be closed are known."

The "spikelet meristem" (SM) plays a central role during the development of the grass inflorescence. Meristems are plant cells or tissues that have the capacity to produce new organs - in this case spikelets. To do this, however, cells destined to become SM must first attain the SM identity. This is achieved, among other things, by gene regulation. As a result, cells develop normally from meristem to organ. The process thus runs from the undifferentiated plant cell to the differentiated organ.

To better understand grass inflorescence architecture, mutants can be very revealing to geneticists. The COM1 barley mutant e.g. is compromised in a way that the corresponding cells cannot perceive or convert the SM identity signal. "Ultimately, the signal transmission does not function properly, so that the cells cannot attain their correct cell identity," explains Dr. Naser Poursarebani, first-author of the study and discoverer of the COM1 gene. To put it simple, the cell does not know what to do in this situation. "Thus, spikelet formation along the main axis of the barley spike, the rachis, cannot proceed normally."

Ultimately, instead of producing a spikelet, a kind of "branch" occurs that looks like a small secondary spike. "Such 'branching', however, is very untypical for all spike-forming grasses belonging to the tribe Triticeae", Prof. Dr. Thorsten Schnurbusch, head of the independent research group Plant Architecture, HEISENBERG Professor of the IPK and the Martin Luther University Halle-Wittenberg and initiator of the study confirms.

In barley, COM1 normally ensures that meristem cells develop into spikelets by influencing the properties of their cell walls and thus ultimately controlling cell growth. COM1's contribution to this identity signal is also its newly discovered function, which is not found in other grasses such as rice, maize, sorghum or twigs (Brachypodium distachyon L.). Barley COM1 function is thus fundamentally different from those above-mentioned grass species, in which the gene rather promotes the formation of inflorescence branches. "From a botanical point of view, COM1 is therefore in any case an important genetic factor for spike formation and shape, about which little has been known until now", explains Prof. Dr. Schnurbusch.

Barley belongs to the grass family (Poaceae) and was domesticated from the wild barley (Hordeum spontaneum) ancestor in the area of the Fertile Crescent about 10,000 years ago. Scientists suspect that the simplified, less complex spike architecture of Triticeae species is related to the spread of those species into zones with a more temperate climate and adaptation to cooler conditions. The newly gained insights into spike development can aid to better understand grass inflorescence evolution but possibly may also help to increase barley's yield potential.

Pioneering analysis of 200 million-year-old teeth belonging to the earliest mammals suggests they functioned like their cold-blooded counterparts - reptiles, leading less active but much longer lives.

The research, led by the University of Bristol, UK and University of Helsinki, Finland, published today in Nature Communications, is the first time palaeontologists have been able to study the physiologies of early fossil mammals directly, and turns on its head what was previously believed about our earliest ancestors.

Fossils of teeth, the size of a pinhead, from two of the earliest mammals, Morganucodon and Kuehneotherium, were scanned for the first time using powerful X-rays, shedding new light on the lifespan and evolution of these small mammals, which roamed the earth alongside early dinosaurs and were believed to be warm-blooded by many scientists. This allowed the team to study growth rings in their tooth sockets, deposited every year like tree rings, which could be counted to tell us how long these animals lived. The results indicated a maximum lifespan of up to 14 years - much older than their similarly sized furry successors such as mice and shrews, which tend to only survive a year or two in the wild.

"We made some amazing and very surprising discoveries. It was thought the key characteristics of mammals, including their warm-bloodedness, evolved at around the same time," said lead author Dr Elis Newham, Research Associate at the University of Bristol, and previously PhD student at the University of Southampton during the time when this study was conducted.

"By contrast, our findings clearly show that, although they had bigger brains and more advanced behaviour, they didn't live fast and die young but led a slower-paced, longer life akin to those of small reptiles, like lizards."

Using advanced imaging technology in this way was the brainchild of Dr Newham's supervisor Dr Pam Gill, Senior Research Associate at the University of Bristol and Scientific Associate at the Natural History Museum London, who was determined to get to the root of its potential.

"A colleague, one of the co-authors, had a tooth removed and told me they wanted to get it X-rayed, because it can tell all sorts of things about your life history. That got me wondering whether we could do the same to learn more about ancient mammals," Dr Gill said.

By scanning the fossilised cementum, the material which locks the tooth roots into their socket in the gum and continues growing throughout life, Dr Gill hoped the preservation would be clear enough to determine the mammal's lifespan.

To test the theory, an ancient tooth specimen belonging to Morganucodon was sent to Dr Ian Corfe, from the University of Helsinki and the Geological Survey of Finland, who scanned it using high-powered Synchrotron X-ray radiation.

"To our delight, although the cementum is only a fraction of a millimetre thick, the image from the scan was so clear the rings could literally be counted," Dr Corfe said.

It marked the start of a six-year international study, which focused on these first mammals, Morganucodon and Kuehneotherium, known from Jurassic rocks in South Wales, UK, dating back nearly 200 million years.

"The little mammals fell into caves and holes in the rock, where their skeletons, including their teeth, fossilised. Thanks to the incredible preservation of these tiny fragments, we were able to examine hundreds of individuals of a species, giving greater confidence in the results than might be expected from fossils so old," Dr Corfe added.

The journey saw the researchers take some 200 teeth specimens, provided by the Natural History Museum London and University Museum of Zoology Cambridge, to be scanned at the European Synchrotron Radiation Facility and the Swiss Light Source, among the world's brightest X-ray light sources, in France and Switzerland, respectively.

In search of an exciting project, Dr Newham took this up for the MSc in Palaeobiology at the University of Bristol, and then a PhD at the University of Southampton.

"I was looking for something big to get my teeth into and this more than fitted the bill. The scanning alone took over a week and we ran 24-hour shifts to get it all done. It was an extraordinary experience, and when the images started coming through, we knew we were onto something," Dr Newham said.

Dr Newham was the first to analyse the cementum layers and pick up on their huge significance.

"We digitally reconstructed the tooth roots in 3-D and these showed that Morganucodon lived for up to 14 years, and Kuehneotherium for up to nine years. I was dumbfounded as these lifespans were much longer than the one to three years we anticipated for tiny mammals of the same size," Dr Newham said.

"They were otherwise quite mammal-like in their skeletons, skulls and teeth. They had specialised chewing teeth, relatively large brains and probably had hair, but their long lifespan shows they were living life at more of a reptilian pace than a mammalian one. There is good evidence that the ancestors of mammals began to become increasingly warm-blooded from the Late Permian, more than 270 million years ago, but, even 70 million years later, our ancestors were still functioning more like modern reptiles than mammals"

While their pace-of-life remained reptilian, evidence for an intermediate ability for sustained exercise was found in the bone tissue of these early mammals. As a living tissue, bone contains fat and blood vessels. The diameter of these blood vessels can reveal the maximum possible blood flow available to an animal, critical for activities such as foraging and hunting.

Dr Newham said: "We found that in the thigh bones of Morganucodon, the blood vessels had flow rates a little higher than in lizards of the same size, but much lower than in modern mammals. This suggests these early mammals were active for longer than small reptiles but could not live the energetic lifestyles of living mammals."

Using telescopes from the European Southern Observatory (ESO) and other organisations around the world, astronomers have spotted a rare blast of light from a star being ripped apart by a supermassive black hole. The phenomenon, known as a tidal disruption event, is the closest such flare recorded to date at just over 215 million light-years from Earth, and has been studied in unprecedented detail. The research is published today in Monthly Notices of the Royal Astronomical Society.

"The idea of a black hole 'sucking in' a nearby star sounds like science fiction. But this is exactly what happens in a tidal disruption event," says Matt Nicholl, a lecturer and Royal Astronomical Society research fellow at the University of Birmingham, UK, and the lead author of the new study. But these tidal disruption events, where a star experiences what's known as spaghettification (https://en.wikipedia.org/wiki/Spaghettification) as it's sucked in by a black hole, are rare and not always easy to study. The team of researchers pointed ESO's Very Large Telescope (VLT - https://www.eso.org/public/teles-instr/paranal-observatory/vlt/) and ESO's New Technology Telescope (NTT - https://www.eso.org/public/teles-instr/lasilla/ntt/) at a new flash of light that occurred last year close to a supermassive black hole, to investigate in detail what happens when a star is devoured by such a monster.

Astronomers know what should happen in theory. "When an unlucky star wanders too close to a supermassive black hole in the centre of a galaxy, the extreme gravitational pull of the black hole shreds the star into thin streams of material," explains study author Thomas Wevers, an ESO Fellow in Santiago, Chile, who was at the Institute of Astronomy, University of Cambridge, UK, when he conducted the work. As some of the thin strands of stellar material fall into the black hole during this spaghettification process, a bright flare of energy is released, which astronomers can detect.

Although powerful and bright, up to now astronomers have had trouble investigating this burst of light, which is often obscured by a curtain of dust and debris. Only now have astronomers been able to shed light on the origin of this curtain.

"We found that, when a black hole devours a star, it can launch a powerful blast of material outwards that obstructs our view," explains Samantha Oates, also at the University of Birmingham. This happens because the energy released as the black hole eats up stellar material propels the star's debris outwards.

The discovery was possible because the tidal disruption event (https://en.wikipedia.org/wiki/Tidal_disruption_event) the team studied, AT2019qiz, was found just a short time after the star was ripped apart. "Because we caught it early, we could actually see the curtain of dust and debris being drawn up as the black hole launched a powerful outflow of material with velocities up to 10 000 km/s," says Kate Alexander, NASA Einstein Fellow at Northwestern University in the US. "This unique 'peek behind the curtain' provided the first opportunity to pinpoint the origin of the obscuring material and follow in real time how it engulfs the black hole."

The team carried out observations of AT2019qiz, located in a spiral galaxy in the constellation of Eridanus, over a 6-month period as the flare grew in luminosity and then faded away. "Several sky surveys discovered emission from the new tidal disruption event very quickly after the star was ripped apart," says Wevers. "We immediately pointed a suite of ground-based and space telescopes in that direction to see how the light was produced."

Multiple observations of the event were taken over the following months with facilities that included X-shooter (https://www.eso.org/public/teles-instr/paranal-observatory/vlt/vlt-instr/x-shooter/) and EFOSC2 (https://www.eso.org/public/teles-instr/lasilla/ntt/efosc2/) , powerful instruments on ESO's VLT and ESO's NTT, which are situated in Chile. The prompt and extensive observations in ultraviolet, optical, X-ray and radio light revealed, for the first time, a direct connection between the material flowing out from the star and the bright flare emitted as it is devoured by the black hole. "The observations showed that the star had roughly the same mass as our own Sun, and that it lost about half of that to the monster black hole, which is over a million times more massive," says Nicholl, who is also a visiting researcher at the University of Edinburgh.

The research helps us better understand supermassive black holes and how matter behaves in the extreme gravity environments around them. The team say AT2019qiz could even act as a 'Rosetta stone' for interpreting future observations of tidal disruption events. ESO's Extremely Large Telescope (ELT), planned to start operating this decade, will enable researchers to detect increasingly fainter and faster evolving tidal disruption events, to solve further mysteries of black hole physics.

A rare blast of light, emitted by a star as it is sucked in by a supermassive black hole, has been spotted by scientists using telescopes from around the world.

The phenomenon, known as a tidal disruption event, is the closest flare of its kind yet recorded, occurring just 215 million light-years from Earth. It is caused when a star passes too close to a black hole and the extreme gravitational pull from the black hole shreds the star into thin streams of material - a process called 'spaghettification'. During this process some of the material falls into the black hole, releasing a bright flare of energy which astronomers can detect.

Tidal disruption events are rare and not always easy to study because they are usually obscured by a curtain of dust and debris. An international team of scientists led by the University of Birmingham were able to study this event in unprecedented detail because it was detected just a short time after the star was ripped apart.

Using the European Southern Observatory's Very Large Telescope and New Technology Telescope, the Las Cumbres Observatory global telescope network, and the Neil Gehrel's Swift Satellite, the team was able to monitor the flare, named AT2019qiz, over a six-month period as it grew brighter and then faded away.

The study's findings are published in Monthly Notices of the Royal Astronomical Society. This was supported and funded in part by the Science and Technology Facilities Council (STFC).

"The idea of a black hole 'sucking in' a nearby star sounds like science fiction. But this is exactly what happens in a tidal disruption event," says lead author Dr Matt Nicholl, a lecturer and Royal Astronomical Society research fellow at the University of Birmingham. "We were able to investigate in detail what happens when a star is eaten by such a monster."

"When a black hole devours a star, it can launch a powerful blast of material outwards that obstructs our view," explains Samantha Oates, also at the University of Birmingham. "This happens because the energy released as the black hole eats up stellar material propels the star's debris outwards."

In the case of AT2019qiz, astronomers were able to identify the phenomenon early enough to observe the whole process.

"Several sky surveys discovered emission from the new tidal disruption event very quickly after the star was ripped apart," says Thomas Wevers, an ESO Fellow in Santiago, Chile, who was at the Institute of Astronomy, University of Cambridge, UK, when he conducted the work. "We immediately pointed a suite of ground-based and space telescopes in that direction to see how the light was produced."

The prompt and extensive observations in ultraviolet, optical, X-ray and radio light revealed, for the first time, a direct connection between the material flowing out from the star and the bright flare emitted as it is devoured by the black hole.

"The observations showed that the star had roughly the same mass as our own Sun, and that it lost about half of that to the black hole, which is over a million times more massive," said Nicholl, who is also a visiting researcher at the University of Edinburgh.

"Because we caught it early, we could actually see the curtain of dust and debris being drawn up as the black hole launched a powerful outflow of material with velocities up to 10 000 km/s," said Kate Alexander, NASA Einstein Fellow at Northwestern University in the US. "This unique 'peek behind the curtain' provided the first opportunity to pinpoint the origin of the obscuring material and follow in real time how it engulfs the black hole."

The research helps astronomers better understand supermassive black holes and how matter behaves in the extreme gravity environments around them. The team say AT2019qiz could even act as a 'Rosetta stone' for interpreting future observations of tidal disruption events. ESO's Extremely Large Telescope (ELT), planned to start operating this decade, will enable researchers to detect increasingly fainter and faster evolving tidal disruption events, to solve further mysteries of black hole physics.

It's been three years since the landmark detection of a neutron star merger from gravitational waves. And since that day, an international team of researchers led by University of Maryland astronomer Eleonora Troja has been continuously monitoring the subsequent radiation emissions to provide the most complete picture of such an event.

Their analysis provides possible explanations for X-rays that continued to radiate from the collision long after models predicted they would stop. The study also reveals that current models of neutron stars and compact body collisions are missing important information. The research was published on October 12, 2020, in the journal Monthly Notices of the Royal Astronomical Society.

"We are entering a new phase in our understanding of neutron stars," said Troja, an associate research scientist in UMD's Department of Astronomy and lead author of the paper. "We really don't know what to expect from this point forward, because all our models were predicting no X-rays and we were surprised to see them 1,000 days after the collision event was detected. It may take years to find out the answer to what is going on, but our research opens the door to many possibilities.

The neutron star merger that Troja's team studied--GW170817--was first identified from gravitational waves detected by the Laser Interferometer Gravitational-wave Observatory and its counterpart Virgo on August 17, 2017. Within hours, telescopes around the world began observing electromagnetic radiation, including gamma rays and light emitted from the explosion. It was the first and only time astronomers were able to observe the radiation associated with gravity waves, although they long knew such radiation occurs. All other gravity waves observed to date have originated from events too weak and too far away for the radiation to be detected from Earth.

Seconds after GW170817 was detected, scientists recorded the initial jet of energy, known as a gamma ray burst, then the slower kilonova, a cloud of gas which burst forth behind the initial jet. Light from the kilonova lasted about three weeks and then faded. Meanwhile, nine days after the gravity wave was first detected, the telescopes observed something they'd not seen before: X-rays. Scientific models based on known astrophysics predicted that as the initial jet from a neutron star collision moves through interstellar space, it creates its own shockwave, which emits X-rays, radio waves and light. This is known as the afterglow. But such an afterglow had never been observed before. In this case, the afterglow peaked around 160 days after the gravity waves were detected and then rapidly faded away. But the X-rays remained. They were last observed by the Chandra X-ray Observatory two and a half years after GW170817 was first detected.

The new research paper suggests a few possible explanations for the long-lived X-ray emissions. One possibility is that these X-rays represent a completely new feature of a collision's afterglow, and the dynamics of a gamma ray burst are somehow different than expected.

"Having a collision so close to us that it's visible opens a window into the whole process that we rarely have access to," said Troja, who is also a research scientist at NASA's Goddard Space Flight Center. "It may be there are physical processes we have not included in our models because they're not relevant in the earlier stages that we are more familiar with, when the jets form."

Another possibility is that the kilonova and the expanding gas cloud behind the initial jet of radiation may have created their own shock wave that took longer to reach Earth.

"We saw the kilonova, so we know this gas cloud is there, and the X-rays from its shock wave may just be reaching us," said Geoffrey Ryan, a postdoctoral associate in the UMD Department of Astronomy and a co-author of the study. "But we need more data to understand if that's what we're seeing. If it is, it may give us a new tool, a signature of these events that we haven't recognized before. That may help us find neutron star collisions in previous records of X-ray radiation."

A third possibility is that something may have been left behind after the collision, perhaps the remnant of an X-ray emitting neutron star.

Much more analysis is needed before researchers can confirm exactly where the lingering X-rays came from. Some answers may come in December 2020, when the telescopes will once again be aimed at the source of GW170817. (The last observation was in February, 2020.)

"This may be the last breath of an historical source or the beginning of a new story, in which the signal brightens up again in the future and may remain visible for decades or even centuries," Troja said. "Whatever happens, this event is changing what we know about neutron star mergers and rewriting our models."

In an elegant choreography, plants take cues from their environment and channel them into flowers, roots, or branches. In a new paper in Nature Communications, biologist Doris Wagner of the School of Arts & Sciences and colleagues identified some of the behind-the-scenes machinations that go into arriving at these variations in plant architecture.

Long interested in the translation of these environmental inputs to physical traits, Wagner and her team have been studying two key groups of proteins that influence plant form and timing of developmental transitions. Terminal Flower 1 (TLF1) proteins promote branch formation. When it is repressed, flowers grow. Flowering Locus T (FT) proteins, on the other hand, promote flowering in response to seasonal cues like day length. Strangely enough, the two proteins are almost identical.

"These two elements have significance galore," Wagner says. "Besides flowering, they're involved in tuberization in potatoes, bulb formation in onions, tendril formation in grapes, growth cessation in trees, lots of things."

Manipulating these genes, some have argued, could lead to the next "green revolution" as one could theoretically "trick" a plant that normally only flowers in the long days of summer to flower quickly, and thus produce fruit or seed, in the short days of winter with a deft genetic edit of TFL1. Or, in an area with a longer growing season, a clever manipulation of growth architecture via FT could encourage increased branching and then a later, and more abundant, flowering and fruit development on the many branches.

Plants have already been bred to have reduced TFL1 activity. Tomato gardeners may know these as determinant plants, which set all their flowers at the same time, as opposed to the indeterminant variety, which continue to branch, flower, and fruit over a period of months. Determinant plants make commercial agriculture more efficient, as fruits can be harvested in one go as opposed to repeated passes.

It was known that TFL1 and FT1 acted in opposing directions, each "tuning" the activity of the other, but the mechanism of their antagonism has remained fuzzy. In part this was because studying them has presented a technical challenge: They are only present in low levels in a limited number of cells.

Wagner's groups, however, had overcome similar challenges in studying a regulator of plant chromatin in earlier work, so they were undeterred in taking on these two dueling proteins.

In the current study, to flesh out TFL1 and FT1's molecular mechanism, they first looked to see where TFL1 was found in the nuclei of plant cells, using the model species Arabidopsis thaliana. They found thousands of sites to which it bound, acting through the transcription factor FD, as neither TFL1 nor FT otherwise can bind directly to DNA. The sites to which TFL1 was recruited were consistent with its role in suppressing flowering and in suppressing gene expression.

The researchers next examined the relationship of both TFL1 and FT with LEAFY, a gene that is known to give rise to flowers. When they mutated the sites where TFL1 regulates the LEAFY gene, LEAFY protein was now found in parts of the plant where TFL1 is present.

"We also saw something that we didn't expect," Wagner says. "LEAFY was gone from all the regions that should make flowers."

That suggested to the team that an unknown factor may be activating the LEAFY gene specifically in the flowering portion of plants via the same site through which TFL1 acts. So, they looked to FT, because of its importance in promoting flowering. By experimentally augmenting FT expression, they found that FT, also binding to the FD transcription factor, was required to act upon LEAFY to promote flower formation.

Seeing that FT and TFL1 both required FD in order to act, they sought to confirm how this competition played in plants. "We wanted to really test its biological contribution: What does it mean to the plant to lose this?" Wagner says.

They saw that under conditions that would normally induce the plant to flower, plants that still had normal FT failed to. "It was a strong phenotype and made it very clear to us that FT and TFL1 compete for this FD factor binding site," she says.

TFL1 and FT are mobile and easily convert from one to another. Wagner is very interested in learning more about their mechanism of action to understand how plants can "tune" their growth to best adapt to their environment. In future work, she and her lab plan to continue working out the details, including how both proteins respond to cues from the environment like day length or shade under a tree. She also wants to know how they can control such different processes like flower, bulb, or tendril formation.

And Wagner believes the findings have ample potential for applications in plant breeding and agriculture. "You can imagine locally adapting crops, maybe for a high-altitude site in the Himalayas or maybe a location in the far north where days are short," she says. "These elements could even play a role in rational solutions for climate change, breeding plants that are specifically adapted for new conditions."

PITTSBURGH, Oct. 12, 2020 - Variations in a gene that regulates dopamine levels in the brain may influence the mobility of elderly and frail adults, according to new research from the University of Pittsburgh Graduate School of Public Health.

These results, published today in the Journal of The American Geriatrics Society, add to a growing body of evidence hinting that lower dopamine levels could contribute to the slower, often disabling walking patterns seen in some elderly populations.

"Most people think about dopamine's role in mobility in the context of Parkinson's disease, but not in normal aging," said senior author Caterina Rosano, M.D., M.P.H., professor of epidemiology at Pitt Public Health. "We were curious to see if a genetic predisposition to produce more or less dopamine was related to mobility in individuals who had some level of frailty, yet did not have dementia, parkinsonism or any other neurological condition."

While several genetic elements control dopamine signaling, Rosano and her team focused on a gene called COMT, which breaks down dopamine to control its levels within the brain. They also considered the frailty status of participants, which is a common consequence of aging marked by a decline in physiological function, poor adjustment to stressors and a susceptibility toward adverse health outcomes. The researchers suspected that frail participants could be particularly vulnerable to COMT-driven differences in dopamine levels.

Rosano and her collaborators examined this gene in more than 500 adults above the age of 65 in Pennsylvania, North Carolina, California and Maryland, excluding any participants taking dopamine-related medications or diagnosed with Parkinson's disease. The researchers then looked for potential links between genotype, frailty and speed.

"We found that in older, frail adults, those who have a high-dopamine genotype are more likely to maintain a faster gait and may be more resilient to mobility disablement as they age," said Rosano.

The team discovered that frail participants with a high-dopamine COMT genotype had a 10% faster walking speed compared with participants with the low-dopamine COMT genotype.

"This 10% difference may seem small, but it could make a big difference for a person walking across a busy street while negotiating traffic," said Rosano. "This difference is even more striking when you consider just how many complex genes influence walking."

Rosano and study co-author Nicolaas Bohnen, M.D., Ph.D., professor of neurology and radiology at the University of Michigan School of Medicine, are working with a team of scientists at Pitt to quantify what level of dopamine could give elders greater resilience to gait-slowing and mobility disablement. Their hope is that older adults with low dopamine levels could one day receive pharmacologic supplements of dopamine to help preserve their mobility.

"There are a lot of individuals living in the community who have dopamine levels toward the lower end of normal who don't have Parkinson's disease or psychiatric conditions," said Rosano. "If we give dopamine to these people, could we make them more resilient? That's what we don't know yet."

In the meantime, she suggests that there are actions that seniors can take today to keep moving. She recommends that elders focus on physical activities that are enjoyable and involve both the body and the brain, especially multi-sensory activities, such as dancing or walking with a loved one.

"I love to see grandparents walking around holding hands with their grandchildren because they have to look where they are going, where the child is going, keep an eye on the surroundings and pay attention to what the grandchild is saying, all at the same time," said Rosano. "They get an amazing multi-sensory rehab, and it's fantastic."

COLUMBUS, Ohio - As COVID-19 cases surged this spring, the pandemic led some people more than others to ponder their own mortality. A new study in China and the United States suggests that these people were the ones who showed the highest levels of stress and the least engagement at work.

But the research also uncovered a bright spot: The right kind of boss helped reduce stress and increase engagement and pro-social behavior in their workers who were anxious about COVID-19.

"A global pandemic can lead some people to think about their own mortality, which will understandably make them more stressed and less engaged at work," said Jia (Jasmine) Hu, lead author of the study and associate professor of management and human resources at The Ohio State University's Fisher College of Business.

"But business leaders who are attentive to employees' emotional needs and unite them behind a common purpose made a positive difference and helped workers stay engaged at work and contribute to their communities."

The study was published online recently in the Journal of Applied Psychology.

The researchers conducted three studies.

One study involved 163 workers at an information technology company in eastern China who filled out surveys twice a day over three weeks while cases of COVID-19 were surging in the country.

Results showed that the more that the employees thought about COVID-19 related deaths, the more anxious they felt and the less engaged they were in their jobs.

But the employees' anxiety and engagement were influenced by the type of boss they had. Employees did better if their boss exhibited what is called "servant leadership." As the name implies, servant leaders prioritize fulfillment of others' needs, attend to employees' emotional suffering, work to empower employees, and emphasize serving the community.

Employees in the study rated on a scale of 1 to 7 how much "My supervisor makes my career development a priority" and other statements that measured servant leadership.

Those who rated their supervisors higher on servant leadership showed less anxiety and were more engaged with their jobs than other employees, Hu said.

"Servant leaders care about their employees' well-being and prioritize their personal growth and happiness at their jobs," she said.

"These types of leaders made it easier for their employees to deal with the anxiety associated with the pandemic."

But servant leaders did more than that: They helped their employees channel their stress into positive behaviors.

The findings showed that employees who rated their bosses as higher on servant leadership were more likely to report that they engaged in pro-social behavior, such as volunteering for a charitable group in their community.

"Servant leaders encouraged their employees to find meaning in the pandemic by channeling their anxiety into helping less fortunate people in their communities," Hu said.

These results were confirmed in two U.S. studies in which participants were told to imagine they were consultants advising a retail company on how to increase sales. The researchers recruited Americans online who said they had full-time jobs.

In both studies, the researchers had participants first read about COVID-19. Half read information that was designed to make them think about how dangerous and deadly the disease is. The other half read less stressful information about COVID-19, such as how to prevent transmission.

Half of the participants read a scenario in which their boss exhibited servant leadership and half read a scenario in which their boss was less supportive.

In one of the two studies, the researchers asked specifically about how much participants were worried about their own deaths.

Results were similar to the study in the Chinese company.

Those who read the more alarming news about COVID-19 reported more anxiety - general anxiety in study two and anxiety related to their own death in study three - than those who read the neutral news.

But once again, in both American studies, those who had servant leaders in their scenarios showed less anxiety, even after reading about how deadly the disease was.

And just like in the Chinese employees, the type of leadership had an impact on pro-social behavior.

Participants were paid a small amount to take part in the studies. At the end, they were given the opportunity to donate some or all of their payment to a charity fighting hunger.

Participants who had servant leaders in their scenarios were more generous to the charity than those whose bosses in the scenarios were less supportive, the study showed.

Overall, the three studies showed that companies play an important role in helping their employees cope with the stress of the COVID-19 pandemic, Hu said, which benefits both the firms and their communities.

"We found that servant leaders who keep their employees' well-being as a top concern can help their anxious workers stay engaged at work and encourage them to contribute to the broader community," she said.

Volume 11, Issue 26 of Oncotarget reported that in this study the authors studied the differences in mi RNA expression between sporadic and FAP-associated Desmoid tumors using microarray confirmed by quantitative PCR.

Among them, mi R-133b levels were significantly lower in FAP-associated Desmoid tumors than in sporadic Desmoid tumors. The qPCR analysis showed that SIRT1 mRNA levels were significantly up-regulated in FAP-associated Desmoid tumor than in sporadic Desmoid tumor, whereas no differences in ELAVL1 expression was observed between these two Desmoid tumor types.

In addition, a negative correlation was observed between mi R-133b and SIRT1 in FAP-associated Desmoid tumors, but not in sporadic Desmoid tumors The mi R-133b-SIRT1-β-catenin axis may represent a novel mechanism underlying progression of FAP-associated Desmoid tumor.

Dr. Maria Teresa Rotelli from The Department of Emergency and Organ Transplantation at The University of Bari “Aldo Moro” in Bari Italy said, "Desmoid tumor (DT) is a rare, mesenchymal benign tumor, characterized by monoclonal, fibroblastic proliferation with local invasiveness, high risk of recurrence and even mortality, despite metastatization never occurs."

The CNNTB1 mutations have been found in approximately 85% of DTs by routine Sanger sequencing, however, using a highly sensitive technique like next-generation sequencing, they may account for 90–95% of sporadic DT cases.

In these DTs, the germline mutations in the APC gene are responsible for the nuclear accumulation of β-catenin.

While the risk of death in sporadic DT is low, FAP-associated DTs are the most frequent cause of death in patients with FAP after the colon has prophylactically been removed.

It must be emphasized that the disruption of the Wnt signaling represents a common pathway in both DT forms, but sporadic and FAP-associated DTs are associated with mutually exclusive molecular alterations.

In a previous study, the authors have investigated a possible correlation between mi RNA expression and CTNNB1 mutations in sporadic DTs.

The Rotelli Research Team concluded in their Oncotarget Research Paper that the dialog between MSCs and tumor cells in FAP-associated DT tissue microenvironment could lead to β-catenin deacetylation driven by SIRT1, promoting Wnt/β-catenin signaling cascade in this tumor.

Although the number of specimens of FAP-associated DTs used in the present study was limited, it could be speculated that the β-catenin deacetylation process in FAP-associated DTs mimics the stabilization of that protein induced by CTNNB1 gene mutations occurring in sporadic DTs.

"It could be speculated that the β-catenin deacetylation process in FAP-associated DTs mimics the stabilization of that protein induced by CTNNB1 gene mutations occurring in sporadic DTs"

Therefore, in addition to APC gene mutations, the mi R-133b-SIRT1-β-catenin axis may represent a novel mechanism underlying the progression of FAP-associated DT. However, further studies are needed to fully understand the influence of mi R-133b-SIRT1 in the genesis or progression of FAP-associated DT.

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DOI - https://doi.org/10.18632/oncotarget.27622

Full text - https://www.oncotarget.com/article/27622/text/

Correspondence to - Maria Teresa Rotelli - mariateresa.rotelli@uniba.it

Keywords -
desmoid tumor,
miRNA,
familial adenomatous polyposis,
B-catenin,
Wnt pathway

About Oncotarget

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Journal

Oncotarget

DOI

10.18632/oncotarget.27622

BEER-SHEVA, Israel -- Many mothers are experiencing an increase in insomnia severity and mild-to-high levels of acute COVID?19 anxiety, according to a new study by researchers at Ben-Gurion University of the Negev and The Max Stern Yezreel Valley College in Israel.

"In the study, we addressed, for the first time, consequences of the COVID?19 pandemic and home confinement on maternal anxiety, insomnia, as well as reports of sleep problems among children between six and 72 months-old," says Prof. Liat Tikotzky, head of the BGU Parenting, Child Development and Sleep Lab and a member of the BGU Department of Psychology. The study was published by the Journal of Sleep Research.

The results indicated that maternal clinical insomnia (Insomnia Severity Score > 15) during the COVID?19 pandemic more than doubled to 23% during the pandemic, compared with only 11% before the pandemic. Approximately 80% of mothers also reported mild?to?high levels of current COVID?19 anxiety.

In the study, mothers were asked to complete a self-reporting questionnaire with reference to two time points: (a) retrospectively one to two months before the COVID?19 outbreak in Israel, and (b) during home confinement. The researchers then computed a score representing the mother's perception of change in her sleep quality.

"We further observed that mothers who reported an increase in insomnia symptoms had significantly higher levels of acute COVID?19 anxiety than mothers who reported no change in insomnia symptoms, while no group differences were detected in their typical (trait) anxiety levels, suggesting that current anxiety may contribute to the increase in severity of insomnia symptoms," Prof. Tikotzky says.

Moreover, the researchers found that about 30% of mothers reported a negative change in their child's sleep quality and a decrease in sleep duration. However, it is important to note that the majority of mothers reported no change in their child's sleep quality, duration, arrangement, and their perception of child's sleep as problematic. Moreover, 12% of mothers even reported a positive change in their child's sleep quality, and 25% reported an increase in sleep duration.

Finally, the researchers observed that mothers who reported higher scores of insomnia were also more likely to report that their children had poorer sleep quality and shorter sleep duration. This is consistent with previous studies demonstrating significant links between maternal and child sleep quality during normal times.

The findings emphasize the importance of further exploring familial resiliency factors that may explain the different patterns of responses in children's and mothers' sleep during times of crises. This is particularly important given the role of sleep in child development and parental functioning.

Wearable sensors are evolving from watches and electrodes to bendable devices that provide far more precise biometric measurements and comfort for users. Now, an international team of researchers has taken the evolution one step further by printing sensors directly on human skin without the use of heat.

Led by Huanyu "Larry" Cheng, Dorothy Quiggle Career Development Professor in the Penn State Department of Engineering Science and Mechanics, the team published their results in ACS Applied Materials & Interfaces.

"In this article, we report a simple yet universally applicable fabrication technique with the use of a novel sintering aid layer to enable direct printing for on-body sensors," said first author Ling Zhang, a researcher in the Harbin Institute of Technology in China and in Cheng's laboratory.

Cheng and his colleagues previously developed flexible printed circuit boards for use in wearable sensors, but printing directly on skin has been hindered by the bonding process for the metallic components in the sensor. Called sintering, this process typically requires temperatures of around 572 degrees Fahrenheit (300 degrees Celsius) to bond the sensor's silver nanoparticles together.

"The skin surface cannot withstand such a high temperature, obviously," Cheng said. "To get around this limitation, we proposed a sintering aid layer -- something that would not hurt the skin and could help the material sinter together at a lower temperature."

By adding a nanoparticle to the mix, the silver particles sinter at a lower temperature of about 212 F (100 C).

"That can be used to print sensors on clothing and paper, which is useful, but it's still higher than we can stand at skin temperature," Cheng said, who noted that about 104 F (40 C) could still burn skin tissue. "We changed the formula of the aid layer, changed the printing material and found that we could sinter at room temperature."

The room temperature sintering aid layer consists of polyvinyl alcohol paste -- the main ingredient in peelable face masks -- and calcium carbonate -- which comprises eggshells. The layer reduces printing surface roughness and allows for an ultrathin layer of metal patterns that can bend and fold while maintaining electromechanical capabilities. When the sensor is printed, the researchers use an air blower, such as a hair dryer set on cool, to remove the water that is used as a solvent in the ink.

"The outcome is profound," Cheng said. "We don't need to rely on heat to sinter."

The sensors are capable of precisely and continuously capturing temperature, humidity, blood oxygen levels and heart performance signals, according to Cheng. The researchers also linked the on-body sensors into a network with wireless transmission capabilities to monitor the combination of signals as they progress.

The process is also environmentally friendly, Cheng said. The sensor remains robust in tepid water for a few days, but a hot shower will easily remove it.

"It could be recycled, since removal doesn't damage the device," Cheng said. "And, importantly, removal doesn't damage the skin, either. That's especially important for people with sensitive skin, like the elderly and babies. The device can be useful without being an extra burden to the person using it or to the environment."

Next, the researchers plan to alter the technology to target specific applications as needed, such as a precise on-body sensor network placed to monitor the particular symptoms associated with COVID-19.

People who have recovered from COVID-19, and their close contacts, could hold the key to understanding how immunity to the disease develops, how long it lasts and what happens when immunity is lost.

The COVID PROFILE study, led by the Walter and Eliza Hall Institute, will use blood samples from people in Victoria to look in detail at immune responses to COVID-19, to reveal how people are protected - and how long people are protected - from future COVID-19 infection. This information is vital for vaccine development - and could explain whether future vaccines can be given once, or whether they will need to be regularly repeated, like the annual influenza vaccine. This information will be critical for planning for the long-term 'COVID-normal' both locally and internationally.

At a glance

Melbourne researchers are investigating the immunity effects of COVID-19

The study is recruiting people who have had COVID-19 and their close contacts who haven't contracted the virus

The research will help inform decisions about vaccine development and other public health measures to control the virus, including operating in a 'COVID-normal' society

Understanding immunity against COVID-19

The study is looking for 300 adult volunteers, both those who have had COVID-19 and those who were close contacts (such as household members) but did not contract the disease. These participants will be followed for 12 months after their exposure to COVID-19, through regular blood samples and nose and throat swabs.

Lead researcher Professor Ivo Mueller said there were big questions in the scientific community about whether people could be re-infected with COVID-19 or how long immunity offered protection against the virus.

"While we know their immune response protects people after they recover from COVID-19, we suspect this protection wanes over time and reinfection of COVID-19 may be possible. We don't know how long this immunity lasts and whether it differs between people who have had severe, mild or asymptomatic infections," he said.

"Understanding immunity to COVID-19 is vital for developing vaccination strategies. It will also drive greater awareness and understanding to help us better manage this virus in the community.

"If we can predict the way immunity to the virus develops over time, whether and when people can be reinfected, and whether symptoms are less severe upon reinfection, we will be able to plan accordingly and stay ahead of the virus," he said.

Explaining different disease outcomes

As researchers across the world race to make sense of this global pandemic, many vital factors remain unknown.

"Concerningly, it may be possible that a second COVID-19 infection could be worse than the first, if immunity has waned. Our study will look closely at whether people could have more severe symptoms if they are re-infected," Professor Mueller said.

Study investigator Dr Vanessa Bryant said the research was crucial in helping to understand the wide range of symptoms experienced by people with COVID-19.

"Some people get severely ill and require hospitalisation, while others are almost completely asymptomatic. Understanding why this happens will help us identify 'biomarkers' that could be used to predict which people may be at higher risk of contracting the virus or developing the most severe symptoms," she said.

"This will enable us to find new treatments that can help strengthen patients' immune systems to help them recover faster."

(Vienna, October 12, 2020) New research presented today at UEG Week Virtual 2020 has shown that delays in colorectal cancer (CRC) screening caused by COVID-19 has resulted in significantly increased death rates for the cancer.

Researchers at the University of Bologna produced a model to forecast the impact of time delays in CRC screening on CRC mortality caused by COVID-19. The results found that moderate (7-12 months) and large (>12 months) delays in screening caused a 3% and 7% increase in advanced stage CRC respectively.

Based on survival rates at 5 years for stage III-IV CRC, the results showed a significant 11.9% increase in deaths when comparing a 0-3 month delay to a >12 month delay.

CRC (or bowel cancer) is Europe's second largest cancer killer and the most common digestive cancer. Annually, there are 375,000 newly diagnosed cases in the EU and it claims the lives of over 170,000 people.

Screening aids the early detection of CRC, and since the rollout of screening programmes across Europe there has been a steady decline in mortality rates. However, since the start of the pandemic, screening programmes have been suspended in many areas across Europe.

Led author of the study, Professor Luigi Ricciardiello, comments, "Across the globe, healthcare systems are facing serious difficulties while dealing with COVID-19 and it is imperative that support is given to the public and patients throughout the crisis, including for high-impact diseases such as colorectal cancer. Healthcare authorities need to act urgently on how they reorganise activities during COVID-19, without compromising the diagnosis of other high-impact diseases like this research shows."

Unhealthy lifestyles, such as diets high in processed foods, smoking and heavy alcohol consumption are linked to the development of CRC. Symptoms include persistent rectal bleeding, a change in bowel habits, abdominal pain and unexplained weight loss.

"Early-stage diagnosis of colorectal cancer is crucial - it's far easier to treat and enhances optimal patient outcomes", adds Professor Ricciardiello. "It is therefore essential that vital diagnosis tools, like screening programmes, continue and help to prevent mortality rates from rising even further."