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The Most Common Stars in Our Galaxy May Be More Habitable Than We Thought

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Red dwarf stars are the most common kind of star in our neighbourhood, and probably in the Milky Way. Because of that, many of the Earth-like and potentially life-supporting exoplanets we’ve detected are in orbit around red dwarfs. The problem is that red dwarfs can exhibit intense flaring behaviour, much more energetic than our relatively placid Sun.

 

So what does that mean for the potential of those exoplanets to actually support life?

Most life on Earth, and likely on other worlds, relies on stellar energy to survive. The Sun has been the engine for life on Earth since the first cells reproduced. But sometimes, like all stars, the Sun acts up and emits flares.

Sometimes it emits extremely energetic flares. The powerful magnetic energy in the Sun’s atmosphere becomes unstable, and an enormous amount of energy is released. If it’s released towards Earth, it can cause problems. It can lead to disruptions in radio communications and even blackouts.

But in terms of flaring activity, the Sun is relatively weak compared to some other stars. Some stars, especially red dwarfs, can flare frequently and violently. A team of researchers studied how flaring activity affects the atmosphere and potential for life on Earth-like planets orbiting low-mass stars, including M-type stars, K-type stars, and G-type stars.

Art of a flaring red dwarf star, orbited by an exoplanet. (NASA/ESA/G. Bacon/STScI)Art of a flaring red dwarf star, orbited by an exoplanet. (NASA/ESA/G. Bacon/STScI)

The new study is called “Persistence of flare-driven atmospheric chemistry on rocky habitable zone worlds“. The lead author is Howard Chen, a PhD student at Northwestern University. The paper is published in the journal Nature Astronomy.

“Our Sun is more of a gentle giant,” said Allison Youngblood, an astronomer at the University of Colorado at Boulder and co-author of the study.

 

“It’s older and not as active as younger and smaller stars. Earth also has a strong magnetic field, which deflects the Sun’s damaging winds.”

That helps explain why Earth is positively “rippling with life” as Carl Sagan described our planet. But for planets orbiting low-mass stars like red dwarfs (M-dwarfs) the situation is much different.

We know that solar flares and associated coronal mass ejections can be very damaging to the prospects of life on unprotected exoplanets. The authors write in their introduction that “[s]tellar activity – which includes stellar flares, coronal mass ejections (CMEs) and stellar proton events (SPEs) – has a profound influence on a planet’s habitability, primarily via its effect on atmospheric ozone.”

A single flare here and there over time doesn’t have much effect. But many red dwarfs exhibit more frequent and prolonged flaring.

“We compared the atmospheric chemistry of planets experiencing frequent flares with planets experiencing no flares. The long-term atmospheric chemistry is very different,” said Northwestern’s Howard Chen, the study’s first author, in a press release.

“Continuous flares actually drive a planet’s atmospheric composition into a new chemical equilibrium.”

 

One of the things the team looked at was ozone, and the effect flares have on it. Here on Earth, our ozone layer helps protects us from the Sun’s UV radiation. But extreme flaring activity on red dwarfs can destroy ozone in the atmosphere of planets orbiting close to it.

When ozone levels drop, a planet is less protected from UV radiation coming from its star. Powerful UV radiation can diminish the possibility of life.

In their study, the team used models to help understand flaring and its effects on exoplanet atmospheres. They used flaring data from NASA’s TESS (Transiting Exoplanet Survey Satellite) and long-term exoplanet climate data from other studies. They found some cases where ozone persisted, despite flaring.

“We’ve found that stellar flares might not preclude the existence of life,” added Daniel Horton, the study’s senior author. “In some cases, flaring doesn’t erode all of the atmospheric ozone. Surface life might still have a fighting chance.”

(Chen et al, 2020)(Chen et al, Nature Astronomy2020)

IMAGE: This figure from the study shows global-mean vertical profiles of atmospheric species on a simulated planet around a Sun-like G-type star. From left to right are the mixing ratios for ozone, nitrous oxide, nitric acid, and water vapour.

Planets that can support life, at least potentially, can be in a tough spot. They must be close enough to their stars to prevent their water from freezing, but not too close or they’re too hot. But this dance with proximity can expose them to the powerful flares.

 

Red dwarfs are smaller and cooler than our Sun, so that means the habitable zone for any planets orbiting them is smaller and much closer to the star than Earth is to the Sun. That not only exposes them to flares but leads to planets being tidally locked to their stars.

The combination of flaring and tidal-locking can be bad for life’s prospects. Earth’s rotation generates its protective magnetosphere, but tidally-locked planets can’t generate one and are largely unprotected from stellar UV radiation.

“We studied planets orbiting within the habitable zones of M and K dwarf stars – the most common stars in the universe,” Horton said.

“Habitable zones around these stars are narrower because the stars are smaller and less powerful than stars like our Sun. On the flip side, M and K dwarf stars are thought to have more frequent flaring activity than our Sun, and their tidally locked planets are unlikely to have magnetic fields helping deflect their stellar winds.”

(Chen et al, 2020)(Chen et al, 2020)

IMAGE: This figure from the study shows how repeated stellar flaring can alter the atmospheric gases in a simulated Earth-like planet around a Sun-like star.

There’s a more positive side to this study as well. The team found that flaring activity can actually help the search for life.

The flares can make it easier to detect some gases which are biomarkers. In this case, they found energy from flaring can highlight the presence of gases like nitric acid, nitrous dioxide, and nitrous oxide, which can all be indicators of living processes.

(Chen et al, 2020)(Chen et al, 2020)

IMAGE: This figure from the study shows how repeated stellar flaring can affect the atmospheric chemistry on a modelled Earth-like planet around a K-type star. Note the raised levels of detectable NO, a potential bio-marker.

“Space weather events are typically viewed as a detriment to habitability,” Chen said.

“But our study quantitatively showed that some space weather can actually help us detect signatures of important gases that might signify biological processes.”

But only some. In other cases, their work showed that flaring can destroy potential biosignatures from anoxic life.

“Although we report the 3D effects of stellar flares on oxidizing atmospheres, strong flares could have other unexpected impacts on atmospheres with reducing conditions. For instance, hydrogen oxide species derived from stellar flares could destroy key anoxic biosignatures such as methane, dimethyl sulfide and carbonyl sulfide, thereby suppressing their spectroscopic features,” the authors report.

Another interesting result of this study concerns exoplanet magnetospheres. They find that hyperflares may help reveal the nature and extent of magnetospheres.

“More speculatively, proton events during hyperflares may reveal the existence of planetary-scale magnetic fields by highlighting particular regions of the planet. By identifying nitrogen- or hydrogen oxide-emitting flux fingerprints during magnetic storms and/or auroral precipitation events, one may be able to determine the geometric extent of exoplanetary magnetospheres.”

(Chen et al, 2020)(Chen et al, 2020)

IMAGE: Hyperflares might help us understand the extent of exoplanet magnetospheres by identifying the extent of nitrogen oxide flux fingerprints.

Other recent research has suggested that exoplanets subjected to flaring, especially around red dwarf stars, are not great locations to search for life. The flaring activity is too detrimental. But this study shows that there’s more complexity to the situation.

Overall it shows that flaring could help us detect biosignatures in some cases. It also shows that while flaring can disrupt exoplanet atmospheres, in many cases they return to normal. It’s also a fact that low-mass stars live much longer than stars like our Sun, meaning there’s more time for life to develop on their planets.

This new work highlights how complicated the search for life is, and how many variables are involved. And it contains at least one surprise. Whereas flaring has been largely considered detrimental to exoplanet habitability, the fact that it may help detect biosignatures means there’s more going on than expected.

This research required cooperation from scientists across many disciplines. It relied on climate scientists, astronomers, observers and theorists, and of course, exoplanet scientists.

“This project was a result of fantastic collective team effort,” said Eric T. Wolf, a planetary scientist at CU Boulder and a co-author of the study.

“Our work highlights the benefits of interdisciplinary efforts when investigating conditions on extrasolar planets.”

This article was originally published by Universe Today. Read the original article.

 



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Here’s How 12,000-Year-Old Weather Can Help Us Predict Future Changes in The Climate

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The end of the last ice age, around 12,000 years ago, was characterised by a final cold phase called the Younger Dryas. Scandinavia was still mostly covered in ice, and across Europe the mountains had many more, and larger, glaciers than today. There was a substantial icefield in the west of Scotland and glaciers could be found on many mountains across the British Isles.

 

Not surprisingly, the climate was colder back then, especially in winter, with temperatures in the UK getting down to -30°C or lower.

Despite these freezing ice-age winters, differences in the Earth’s orbit around the Sun meant the summers were relatively warm, with an average temperature in July between 7°C and 10°C across most of the UK and Ireland.

Then, as now, the polar front jet stream (a high-altitude fast-moving wind belt) had a major influence on the weather across Europe, bringing precipitation (rain and snow) from the Atlantic across the continent.

However, before the time of written climate records, the timing, quantity and pattern of precipitation are poorly understood.

Our new study has used glaciers that existed during the Younger Dryas to determine the precipitation patterns and path of the jet stream across Europe at that time.

We identified glacial landforms called moraines at 122 sites from Morocco in the south to Norway in the north, and from Ireland in the west to Turkey in the east, which demonstrated the presence of glaciers some 12,000 years ago.

 

We reconstructed the 3D geometry of each of these glaciers using knowledge of the way that ice flows across the landscape.

From the reconstructed ice surfaces, we could determine an important point on each of these glaciers, the equilibrium line altitude which is linked to climate via yearly precipitation and average summer temperature.

It is essentially the altitude on the glacier where snow accumulation and snow melt are equal at the end of September and can be seen as the snowline.

The results provided a map of precipitation across Europe about 12,000 years ago which was controlled by the jet stream.

Jet stream weather

What the results showed was that the UK, Ireland, Portugal, and Spain were mostly wetter than the present day, as was the Mediterranean, especially in the east – the Balkans, Greece, and Turkey.

It was relatively drier across much of France, Belgium, the Netherlands, Germany, and farther east across Europe. These areas of wetter and drier climate allowed us to identify the location of the jet stream.

We surmised that the jet stream passed over the wetter regions bringing with it the storms (known as mid-latitude depressions) we are all familiar with in the UK – especially Scotland – and also potentially generated other smaller, more intense storms.

 

Based on the path of the jet stream it is believed that the autumn and spring were wettest in the UK and Ireland and that the winters were drier.

Across Portugal, Spain, and the Mediterranean, the winter months were probably the wettest, with autumn and spring being somewhat drier.

This is the first time that we have had an insight into the seasonal weather patterns across Europe during the Younger Dryas, and indeed such glimpses of past climate, beyond the period for which we have recorded climate observations, are rare.

Normally it is only numerical climate models that reveal such a regional scale view on past atmospheric circulation, storm tracks, and precipitation.

Numerical climate models plot our weather and climate by dividing the atmosphere, Earth’s surface and ocean into multiple interconnected cells, vertically and horizontally, in a three-dimensional grid, and solve complex mathematical equations to determine how energy and matter move through the system.

Changing jet stream

In our study, a comparison of the glacier-derived precipitation from 12,000 years ago was made with the outputs from several palaeoclimate (the study of climate in the past) computer simulations.

Numerical climate models are extremely complex, yet they remain a simplification of reality, so different models inevitably generate outputs which variously agree and disagree.

 

The general pattern of precipitation determined from our study of the palaeo-glaciers agreed with some parts of the climate model outputs, but in disagreement with others – for example, none of the climate models identified all of the UK, Ireland, Portugal, Spain and Mediterranean as being wetter in the past.

We are already seeing signs that the jet stream may be changing as the climate warms and it is thought that it will probably move northwards and become wavier.

These ripples could lead to more extremes, for example, heatwaves in summer and more storms and flooding in the winter.

To understand how climate will change in the future we rely on computer models, but these models do not yet agree on what happened in the past nor on exactly what will happen in the future.

To make better future predictions from ongoing climate warming, palaeoclimate datasets, such as the glacier-derived precipitation determined from our study, can be used to test the computer models.

When the models can better reproduce precipitation patterns reconstructed from past climates, especially in periods when the jet stream has moved, then our confidence in their predictions of future climate will also be boosted.The Conversation

Brice Rea, Professor, Geography, University of Aberdeen.

This article is republished from The Conversation under a Creative Commons license. Read the original article.

 



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For Better or Worse, COVID-19 Put Science Research in Front of More People Than Ever

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COVID-19 has not only upended our personal lives, it has dramatically changed scientific research.

In response to the rapid spread of the virus, scientists around the world have had to find new ways to collaborate and solve problems, all at speeds previously thought unimaginable.

 

Indeed, until very recently, the idea that a new vaccine could be developed, tested and distributed in less than a year would have seemed impossible.

The rapid pace at which science is moving is exciting. In addition to producing vaccines, scientists have found ways to prevent the virus from spreading, dispel pandemic myths, and identify communities most at risk of falling ill.

But the “warp speed” at which science is moving can also be dangerous, especially when inconclusive or unverified research studies gain public attention.

As researchers studying science and health communication, our team has been paying close attention to the way one form of preliminary research — the preprint — makes its way to audiences.

What are preprints?

Preprints are scientific manuscripts that are posted online but haven’t been formally verified by the scientific community. Scientists use them for many reasons, from getting early feedback on new work to sharing findings that are important but may never make it into a journal.

Preprints can also help make research more accessible because they are free to read, while many journal articles are not.

 

They can also be published by scientists without any delays, as opposed to the many months (or even years) it takes for a study to go through peer review and be published in a journal.

For some findings, waiting for a paper to pass through two or three independent researchers — or academic peers — who read the study and assess its rigour, originality, and significance, is a manageable delay.

But for others — like those about promising new drugs, prevention strategies, or medical therapies — speed can make a big difference. In these cases, posting a preprint means that other scientists can start working on replicating the results right away, potentially allowing new treatments or vaccines to be approved months or even years ahead of schedule.

This speed advantage is one reason that preprint use has skyrocketed during the COVID-19 pandemic. When almost 800,000 people worldwide are falling ill every week, faster science isn’t just about convenience: It’s about saving lives.

Preprints in the COVID-19 pandemic

While preprints have an obvious advantage for scientists, things can get tricky when these preliminary studies make their way outside of the scientific community.

Early in the pandemic, for example, two high profile preprints linking tobacco and COVID-19 prevention started to receive a lot of media coverage. Although the studies turned out to be highly flawed, many readers took the findings to heart, sparking unnecessary panic and encouraging smoking.

 

The tentative nature of preprints is one reason journalists have historically been discouraged from reporting on them.

But with the onset of the pandemic, and few relevant peer-reviewed studies to draw on, journalists were left with little choice but to cover these preliminary reports.

Indeed, in the early months of the pandemic, COVID-19-related preprints were more than 200 times as likely to receive media coverage than preprints on other topics, according to a study posted (as a preprint) last year.

In our peer-reviewed study, we found that, unfortunately, the preliminary nature of these studies wasn’t always communicated consistently.

Of the more than 450 media stories we analyzed, only about half accurately portrayed preprints as being uncertain or unverified research.

Surprisingly, it wasn’t just the newer, less traditional media outlets that failed to identify the research as preprints. Even established publications like the New York Times did not always describe the preprints they covered as preliminary.

Staying critical and informed as science evolves

While this coverage of preprints isn’t in and of itself a bad thing, it can be dangerous if the tentative nature of the science isn’t made transparent.

Luckily, journalism associations are starting to develop recommendations for covering preprints responsibly.

 

Preprint servers, or online collections, like bioRxiv and medRxiv, have also started posting “warning” messages alongside new studies to remind readers not to treat the findings as established facts.

Until these best practices become commonplace, however, it’s up to all of us to develop the skills we need to make responsible and well-founded decisions about our health.

Learn to read science papers critically, remember to fact check questionable claims, and, most importantly, always think before you share.

As science communicator Liz Neeley so aptly put it, “We are all science communicators now: COVID-19 has conscripted us.” Preprints may be here to stay, but if we learn to communicate responsibly about this preliminary research, the confusion they generate doesn’t have to be.The Conversation

Alice Fleerackers, PhD Student, Interdisciplinary Studies, Simon Fraser University and Juan Pablo Alperin, Assistant Professor, Simon Fraser University.

This article is republished from The Conversation under a Creative Commons license. Read the original article.

 



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Small Study Links Biomarkers in Sperm to Child’s Autism Status With 90% Accuracy

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Scientists have identified a series of human sperm biomarkers that can accurately predict the chances of the offspring having autism spectrum disorder (ASD) – a potentially important finding for better understanding and managing the condition.

 

Although the study involved a small sample size of only 26 fathers, the strong correlation between the biomarkers and ASD suggest that this thread of research could be worth pulling on to help explain some of the mysteries that still surround the development of autism.

In particular, the researchers looked at sperm epigenetics: changes in the way that genes are expressed and processed by the body, rather than alterations in the underlying DNA code, and often linked to environmental factors.

“We can now potentially use this to assess whether a man is going to pass autism on to his children,” says biologist Michael Skinner, from Washington State University.

“It is also a major step toward identifying what factors might promote autism.”

The study included samples from 13 men who had fathered autistic children (case) and 13 men who hadn’t (control). In an analysis of DNA methylation regions – particular chemical modifications to gene expression – the team identified 805 potential biomarkers.

They then blinded eight of the samples and reanalysed them to determine whether these were case or control. In a further blind test of 10 additional sperm samples, the scientists were able to use their DNA methylation findings to predict whether or not the men had fathered autistic children with an accuracy rate of around 90 percent.

 

Not only could the study be expanded to predict the chances of men fathering autism, but it could also provide clues as to how these epigenetic changes come about in the first place, according to the researchers – perhaps giving us a way to do something about them.

“We found out years ago that environmental factors can alter the germline, the sperm or the egg, epigenetics,” says Skinner. “With this tool, we could do larger population-based studies to see what kinds of environmental factors may induce these types with epigenetic changes.”

With a sharp rise in children diagnosed with ASD across the last few decades, experts are keen to learn as much as possible about the causes of the condition – and if we’re able to predict it, then we should be able to manage it better too.

Although the heritability of autism isn’t something scientists fully understand, fathers are more often linked to passing on ASD than mothers, making the findings of the current research even more valuable.

While the small sample size of this study means it’s too early to start making broad generalisations, the research does show that this is a link worth pursuing – and a bigger clinical trial following the same approach is already being planned.

“Although a large clinical trial is needed to further validate the biomarkers and potential diagnostic, the current study provides the proof of concept for the assay and biomarkers,” write the researchers in their paper.

The research has been published in Clinical Epigenetics.

 



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Scientists Surprised by Geckos Lighting Up Desert Nights With Neon-Green Sides

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A desert gecko from Namibia has brilliant glow-in-the-dark markings that shine neon green by the light of the moon. The mechanism that produces its glow has never been seen before in land animals with backbones.

 

 

Web-footed geckos (Pachydactylus rangei) have translucent skin with large, yellowish markings: stripes on their sides and rings surrounding their eyes. But those markings light up brightly when they absorb the moon’s bluer light.



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Our Forests Are on Track to Hit a Crucial Climate Tipping Point by 2050, Scientists Warn

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Forests and other land ecosystems today absorb 30 percent of humanity’s CO2 pollution, but rapid global warming could transform these natural ‘sinks’ into carbon ‘sources’ within a few decades, opening another daunting front in the fight against climate change, alarmed researchers have said.

 

Climate skeptics often describe CO2 as “plant food”, suggesting that increased greenhouse gas emissions will be offset by a massive upsurge in plant growth.

But the new study shows that beyond a certain temperature threshold – which varies according to region and species – the capacity of plants to absorb CO2 declines.

Under current greenhouse gas emission trends, plants across half the globe’s terrestrial ecosystem could start to release carbon into the atmosphere faster than they sequester it by the end of the century, researchers reported this week in Science Advances.

Ecosystems that store the most CO2 – especially tropical and boreal forests – could lose more than 45 percent of their capacity as carbon sponges by mid-century, a team led by Katharyn Duffy from Northern Arizona University found.

“Anticipated higher temperatures associated with elevated CO2 could degrade land carbon uptake,” said the study, based not on modelling but data collected over a period of 25 years.

Failure to take this into account leads to a “gross overestimation” of the role Earth’s vegetation might play in reducing global warming, the researchers warned.

 

“The temperature tipping point of the terrestrial biosphere lies not at the end of the century or beyond, but within the next 20 to 30 years.”

Key to understanding how this could happen is the difference between photosynthesis and respiration, two chemical processes essential to plant life that respond differently to rising temperatures.

Drawing energy from sunlight, plants absorb carbon dioxide through their leaves and water from the soil, producing sugar to boost growth and oxygen, which is released into the air.

This is photosynthesis, which can only happen when there is daylight.

By contrast, the transfer of energy to cells through respiration – with CO2 excreted as a waste product – happens around the clock.

Tipping points

To find out if there is a temperature beyond which land-based ecosystems would start to absorb less CO2, Duffy and her team analysed records from a global observation network, called FLUXNET, spanning 1991 to 2015.

FLUXNET essentially tracks the movement of CO2 between ecosystems and the atmosphere.

They found that global photosynthesis peaks at certain temperatures, depending on the type of plant, and then declines thereafter.

 

Respirations rates, however, increase across all types of ecosystems without appearing to reach a maximum threshold.

“At higher temperatures, respiration rates continue to rise in contrast to sharply declining rates of photosynthesis,” the study found.

If carbon pollution continue unabated, this divergence will could see the CO2 absorption drop by half as early as 2040.

“We are rapidly entering temperature regimes where biosphere productivity will precipitously decline, calling into question the future viability of the land sink,” the researchers concluded.

The findings also call into question the integrity of many national commitments under the Paris Agreement – known as nationally determined contributions, or NDCs – to reduce greenhouse gases.

“These rely heavily on land uptake of carbon to meet pledges,” the authors point out.

The study notes that capping global warming under two degrees Celsius above pre-industrial levels, the cornerstone target of the 2015 Paris climate treaty, “allows for near-current levels of biosphere productivity, preserving the majority of land carbon uptakes.”

Earth has warmed at least 1.1C so far, and is currently on track to heat up another two to three degrees by century’s end unless emissions are rapidly and drastically reduced.

In 2019, a football pitch of primary, old-growth trees was destroyed in the tropics every six seconds – about 38,000 square kilometres (14,500 square miles) in all, according to satellite data.

© Agence France-Presse

 



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Research Finds There’s More Than One Type of Curiosity. Which Do You Have?

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Curiosity affects everything from our relationships to our education, but it’s not easy to pin down and put under a microscope to study. With the help of Wikipedia though, researchers have now done just, exploring two main types of curiosity.

 

Using Wikipedia browsing as an activity to observe, and a maths technique called graph theory to formally chart and measure it, 149 participants were observed browsing for 15 minutes a day over the course of 21 days, covering 18,654 pages in total.

The resulting study was able to split the individuals into two previously identified types, as far as curiosity goes: the ‘busybody’ who explores a lot of diverse information, and the ‘hunter’ who stays on a more focused track when it comes to gaining knowledge.

curious 2Wikipedia browsing behaviour was used to analyse curiosity. (Lydon-Staley et al, Nature Human Behaviour 2021)

“Wikipedia allowed both introverts and extroverts to have equal opportunity in curious practice, a limitation in other studies of curiosity, while the ad-free search engine allowed individuals to truly be captains of their own curiosity ships,” says biophysicist Danielle Bassett, from the University of Pennsylvania.

By recording pages as nodes and analysing how closely they were related, Bassett and her colleagues were able to find both busybodies and hunters in their pool of volunteers – those who tended to jump all around Wikipedia and those who were more likely to stay on closely related pages.

 

However, the participants didn’t always stick to one type of behaviour or the other, and the researchers wanted to find out why. To do this, they used a wellbeing questionnaire given to the participants before the study began, covering topics like seeking out social interaction and tolerating stress.

Based on the surveys, a need to fill specific knowledge gaps seemed to drive hunter-style behaviour, while a desire to seek out brand new information was an indicator of a busybody-style of Wikipedia browsing – taking larger leaps between nodes or pages.

“We hypothesise that a switch from hunter to busybody style might arise due to sensation seeking, or the craving for novelty and new information during the day,” says Bassett.

One of the reasons that this study stands out is that it looks at how curiosity is expressed – rather than trying to quantify it through engagement in activities like asking questions, playing trivia games, and gossiping, as previous studies have done.

These findings can be useful in a number of ways, including in informing approaches to teaching – particularly in how knowledge and resources can be best presented, and how different problem-solving styles can be supported.

Curiosity is also linked to emotional wellbeing: people who are more curious tend to be more satisfied with life and less anxious. By making sure information is available in ways that are accessible, we can foster curiosity and promote contentment at the same time.

“We need more data to know how to use this information in the classroom, but I hope it discourages the idea that there are curious and incurious people,” says psychologist David Lydon-Staley, from the University of Pennsylvania.

The research has been published in Nature Human Behaviour.

 



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Earliest Animal Cave Art on Record Has Been Found in Indonesia, And It’s Adorable

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The oldest-known animal drawing in the world is a 45,500-year-old depiction of a hairy, warty pig on a cave wall in Indonesia, a new study finds.

The mulberry colored painting, drawn with the red mineral ochre, shows the profile of what is likely a Sulawesi warty pig (Sus celebensis), a wild stubby-legged beast with facial warts that can weigh up to nearly 190 pounds (85 kilograms).

 

These pigs “are still found there today, although in ever-dwindling numbers,” said study co-lead researcher Adam Brumm, a professor of archaeology at Griffith University’s Australian Research Centre for Human Evolution.



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Rare 4-Stranded DNA Has Been Observed in Action For The First Time

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Two thin strands wound together in a spiraling helix: This is the iconic shape of a DNA molecule. But sometimes, DNA can form a rare quadruple-helix, and this odd structure may play a role in diseases like cancer

 

Not much is known about these four-stranded DNA, known as G-quadruplexes — but now, scientists have developed a new way to detect these odd molecules and observe how they behave in living cells.

In a new study, published January 8 in the journal Nature Communications, the team described how certain proteins cause the G-quadruplex to unravel; in the future, their work could lead to new drugs that grab hold of quadruple-helix DNA and disrupt its activity.

Drugs could intervene, for instance, when the odd DNA contributes to cancerous tumor growth.  

“Evidence has been mounting that G-quadruplexes play an important role in a wide variety of processes vital for life, and in a range of diseases,” study author Ben Lewis, from the Department of Chemistry at Imperial College London, said in a statement

Related: 7 diseases you can learn about from a genetic test 

In general, G-quadruplexes crop up in cancer cells at much higher rates than healthy cells, according to the statement. 

Various studies have linked the presence of four-stranded DNA to the rapid division of cancer cells, a process that leads to tumor growth; so scientists hypothesized that targeting the weird DNA with drugs could slow or stop this unbridled cell division. Some studies already support this idea.  

 

“But the missing link has been imaging this structure directly in living cells,” Lewis said. In other words, scientists needed a better way to watch these DNA molecules in action.

The new study begins to fill in that missing knowledge.

G-quadruplexes can form either when one double-stranded DNA molecule folds over on itself or when multiple DNA strands link up at a single nucleic acid, known as guanine — one of the building blocks of DNA, according to Discover Magazine.

To spot this funky DNA in cells, the team used a chemical called DAOTA-M2, which emits a fluorescent light when it binds to G-quadruplexes. Rather than only measuring the brightness of the light, which varies depending on the concentration of DNA molecules, the team also tracked how long the light shone.

Tracking how long the light lingered helped the team see how different molecules interacted with the four-stranded DNA in living cells.

When a molecule latched onto the DNA strand, it would displace the glowing DAOTA-M2, causing the light to go out faster than if the chemical had remained in place. Using these methods, the team identified two proteins, called helicases, that unwind the strands of four-stranded DNA and jumpstart the process of breaking them down.

 

They also identified other molecules that bind to the DNA; future studies on these molecular interactions could help scientists design drugs that bind to the DNA.

“Many researchers have been interested in the potential of G-quadruplex-binding molecules as potential drugs for diseases such as cancers,” Ramon Vilar, a professor of medicinal inorganic chemistry at Imperial, said in the statement.

“Our method will help to progress our understanding of these potential new drugs.”

Related content:

Genetics by the numbers: 10 tantalizing tales

7 odd things that raise your risk of cancer (and 1 that doesn’t)

Science experiment for kids: Seeing your DNA 

This article was originally published by Live Science. Read the original article here.

 



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6 Months After Infection, 76% of COVID-19 Patients Are Still Suffering Symptoms

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More than three quarters of people hospitalised with COVID-19 still suffered from at least one symptom after six months, according to a study published Saturday that scientists said shows the need for further investigation into lingering coronavirus effects.

 

The research, which was published in the Lancet medical journal and involved hundreds of patients in the Chinese city of Wuhan, is among the few to trace the long-term symptoms of COVID-19 infection.

It found that fatigue or muscle weakness were the most common symptoms, while people also reported sleeping difficulties.

“Because COVID-19 is such a new disease, we are only beginning to understand some of its long-term effects on patients’ health,” said senior author Bin Cao, of the National Center for Respiratory Medicine.

The professor said the research highlighted the need for ongoing care for patients after they have been discharged from hospital, particularly those who have had severe infections.

“Our work also underscores the importance of conducting longer follow-up studies in larger populations in order to understand the full spectrum of effects that COVID-19 can have on people,” he added.

The World Health Organization has said the virus poses a risk for some people of serious ongoing effects – even among young, otherwise healthy people who were not hospitalised.

The new study included 1,733 COVID-19 patients discharged from Jinyintan Hospital in Wuhan between January and May last year.

 

Patients, who had an average age of 57, were visited between June and September and answered questions on their symptoms and health-related quality of life.

Researchers also conducted physical examinations and lab tests.

The study found that 76 percent of patients who participated in the follow-up (1,265 of 1,655) said they still had symptoms.

Fatigue or muscle weakness was reported by 63 percent, while 26 percent had sleep problems.

The study also looked at 94 patients whose blood antibody levels were recorded at the height of the infection as part of another trial.

When these patients were retested after six month, their levels of neutralising antibodies were 52.5 percent lower.

The authors said this raises concerns about the possibility of COVID-19 re-infection, although they said larger samples would be needed to clarify how immunity to the virus changes over time.

In a comment article also published in The Lancet, Monica Cortinovis, Norberto Perico, and Giuseppe Remuzzi, from Italy’s Istituto di Ricerche Farmacologiche Mario Negri IRCCS, said there was uncertainty over the long-term health consequences of the pandemic.

“Unfortunately, there are few reports on the clinical picture of the aftermath of COVID-19,” they said, adding the latest study was therefore “relevant and timely”.

They said longer term multidisciplinary research being conducted in the United States and Britain would help improve understanding and help develop therapies to “mitigate the long-term consequences of COVID-19 on multiple organs and tissues”.

© Agence France-Presse

 



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