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Octopuses May Be Adapting to The Rising Acidity of Our Oceans, Study Suggests

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We know that all the excess CO2 we’re pumping into the air – alongside a host of other damaging effects – is driving up the acidity of the oceans as it sinks and dissolves into the water, but it seems as though the hardy octopus can find ways to adapt to its rapidly changing environment.

 

Previous research into the impact of ocean acidification on cephalopods such as octopuses, cuttlefish, and squid has shown some indication increased carbon dioxide in the water could negatively impact this type of marine life.

However, in a new study, a group of Octopus rubescens – a species of octopus common to the west coast of North America – were observed adjusting their routine metabolic rate (RMR) over a series of weeks in response to lowering pH levels in the surrounding water.

“Challenges to an organism’s physiology are often reflected in changes in energy use and therefore can be observed as changes in aerobic metabolic rate,” write the researchers in their paper.

A total of 10 octopuses were studied under controlled lab conditions, with RMR measured immediately after exposure to acidic water, after one week, and after five weeks. Critical oxygen pressure – a measure of whether not not animals are getting enough oxygen – was monitored at the same time.

To begin with, high levels of metabolic change were detected in the creatures – a sort of shock reaction that actually conflicts with earlier research into cephalopods, which had recorded a reduction in metabolic change in similar scenarios.

 

However, RMR had returned to normal after one week, and remained the same five weeks later, suggesting some adaptation had occurred. The increased acidity did have an impact on the ability of the octopuses to function at low oxygen levels, however.

“This response in RMR suggests that O. rubescens is able to acclimate to elevated CO2 over time,” write the researchers. “The observed increase in RMR may be the result of multiple acute responses to hypercapnia [increased CO2 in the blood], possibly including both behavioural and physiological strategies.”

Those strategies could include preparing to move to find a new stretch of water to inhabit, for example, the researchers suggest (something that wasn’t possible here). The short RMR boost might also reflect the octopuses making quick adjustments to their biological processes to suit the new acid level.

The study is the first to look at both short-term (one week) and longer-term (five week) changes in metabolism rates in cephalopods in response to ocean acidification. We know these creatures are tough, and it seems they even have coping strategies that might allow them to adapt to humans destroying the natural environment all around them.

None of this means that we should be okay with the current climate crisis though, or not be trying to make major changes to reverse it. When we don’t take proper care of the planet, it’s not just ourselves that we’re potentially dooming to extinction.

Also, these tests were done in controlled laboratory conditions that don’t take into account many other interlinking factors in the animals’ natural environment. For instance, even if the octopus themselves are able to adjust, what about their food supply?

“While this species may be able to acclimate to near-term ocean acidification, compounding environmental effects of acidification and hypoxia may present a physiological challenge for this species,” write the researchers.

The research has been published in Physiological and Biochemical Zoology.

 



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Scientists Discover a New Type of Chemical Bond, And It’s Surprisingly Strong

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Scientists have recently discovered a totally new type of chemical bond – and it’s way stronger than it has any right to be.

The new type of bond shows that the divide between powerful covalent bonds, which bind molecules together, and weak hydrogen bonds, which form between molecules and can be broken by something as simple as stirring salt into a glass of water, isn’t as clear as chemistry textbooks would suggest.

 

Think back to that high-school chemistry class, and you’ll remember that there are different types of bonds that link atoms together into molecules and crystal structures. 

Ionic bonds link metals and non-metals to form salts. Strong covalent bonds bind together molecules like carbon dioxide and water. Far weaker hydrogen bonds form because of an electrostatic type of attraction between hydrogen and a more negatively charged atom or molecule, for instance causing water molecules to attract one another and form droplets or crystalline ice.

Ionic, covalent, and hydrogen bonds are all relatively stable; they tend to last for extended periods of time and have effects are easily observable.

But researchers have long known that during a chemical reaction, as chemical bonds are forming or breaking, the story is more complicated and involves “intermediate states” that may exist for tiny fractions of a second and are more difficult to observe. 

In the new study, the researchers managed to keep these intermediate states going for long enough to make a detailed examination. What they found was a hydrogen bond with the strength of a covalent bond, binding atoms together into something resembling a molecule.

 

To do that, the researchers dissolved a hydrogen-fluoride compound in water and watched how the hydrogen and fluorine atoms interacted. The fluorine atoms were attracted to the hydrogen atoms due to imbalances of positive and negative charges across their surfaces, the classic structure of a hydrogen bond. Each hydrogen atom tended to be sandwiched between two fluorine atoms.

But those sandwiches were bound together with more strength than typical hydrogen bonds, which are easily broken. The hydrogen atoms bounced back and forth between the fluorine atoms, forming bonds as strong as covalent bonds and resembling molecules, which hydrogen bonds shouldn’t be able to form.

But the mechanism of the new bond was electrostatic, meaning it involved the sort of differences in positive and negative charge that define hydrogen bonds.

The new bonds had a strength of 45.8 kilocalories per mol (a unit of chemical bonding energy), greater than some covalent bonds. Nitrogen molecules, for example, are made of two nitrogen atoms bound together with a strength of about 40 kcal/mol, according to LibreTexts.

A hydrogen bond typically has an energy of about 1 to 3 kcal/mol, according to the book Biochemistry.

 

They described their results in a paper published Thursday (Jan. 7) in the journal Science. In an accompanying article in Science, Mischa Bonn and Johannes Hunger, researchers at the Max Planck Institute for Polymer Research in Germany, who were not involved in the study, wrote that this unusual bond blurs the clear categories of chemistry

“The existence of a hybrid covalent-hydrogen bonded state not only challenges our current understanding of what a chemical bond exactly is, but also offers the opportunity to better understand chemical reactions,” they wrote, “where ‘intermediate reaction states’ are often invoked but rarely studied directly.” 

Similar bonds likely exist in pure water, they wrote, when a hydrogen atom finds itself sandwiched between two water molecules. But those bonds are believed to exist but not be as long-lived, the researchers wrote. And they’ve never been conclusively observed.

This study, they wrote, could open the door to a “deeper understanding of strong bonding” and the intermediate reaction states. 

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

 



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Huge Underground Reservoir of Freshwater Discovered Off The Coast of Hawai’i

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For a long time, Hawai’i Island has been home to a mystery. Somehow, the amount of freshwater in underground aquifers has seemed much smaller than it should be, given the amount of rainfall.

 

Scientists have just found out why. Deep underground, running below the island’s coast, vast quantities of freshwater are transported from the flanks of the volcano Hualālai down into newly discovered reservoirs that run deep below the ocean floor.

It’s a discovery that has implications for volcanic islands around the world – an untapped potential renewable resource that could prove invaluable as the global climate rapidly changes.

“Our findings provide a paradigm shift from the conventional hydrologic conceptual models that have been vastly used by multiple studies and water organisations in Hawaiʻi and other volcanic islands to calculate sustainable yields and aquifer storage for the past 30 years,” said geophysicist Eric Attias of the University of Hawaiʻi.

“We hope that our discovery will enhance future hydrologic models, and consequently, the availability of clean freshwater in volcanic islands.”

Most of Hawaii’s freshwater is retrieved from aquifers, layers of water-permeable rock or sediment. When rain falls, it percolates through the topsoil and volcanic rock beneath, eventually reaching the deep aquifer reservoirs.

Recent research has suggested that there is far less water in these aquifers than there should be. Studies have found that large quantities of nutrient-rich groundwater are leaking into the ocean, and isotope analyses suggest that there’s a huge discrepancy between how much water is going into the aquifers, and how much is retained therein.

 

To get to the bottom of this discrepancy, Attias and his team turned to electromagnetic imaging.

This is somewhat ingenious, exploiting the conductive properties of salt and fresh water. Freshwater is not very conductive at all. However, the salts dissolved in large amounts in seawater provide plenty of positive and negative ions to transport electrical currents much more efficiently.

The team took a boat along the coastline, towing an electromagnetic system behind them that propagated an electromagnetic field through the water, covering an area 40 kilometres (25 miles) long and 4 kilometres (2.5 miles) wide, producing a trail of electromagnetic data running continuously around 200 kilometres along the coast.

This data revealed regions of higher and lower conductivity along the Kona coastline, allowing the team to map freshwater outflows and their associated reservoirs.

“I have spent my entire career developing marine electromagnetic methods such as the one used here,” said geophysicist Steven Constable of the Scripps Institution of Oceanography, who developed the system.

“It is really gratifying to see the equipment being used for such an impactful and important application. Electrical methods have long been used to study groundwater on land, and so it makes sense to extend the application offshore.”

layersConceptual model of freshwater path from rainfall to offshore. (Attias et al., Science Advances, 2020)

The team found that there are underground freshwater rivers in layers between saltwater-saturated volcanic basalts. These rivers are around 35 kilometres long extending at least 4 kilometres west of the coastline.

The reservoirs, the researchers estimate, contain around 3.5 cubic kilometres of fresh water – around 1.4 million Olympic swimming pools’ worth, and twice as much as previously estimated.

 

This could change how communities on volcanic islands like Hawai’i deal with a changing climate. The increasing frequency of droughts is likely to decrease the amount of rainfall replenishing the underground aquifers.

Changing the landscape too much can have a negative impact, too; rainforests, for example, help catch the water, channelling the water along plants to a soil layer that retains water and filters it into the ground.

If the forest degrades, this soil layer becomes eroded, and water flows away across the surface, further depleting the aquifers.

The submarine aquifers are more resilient, and could – with careful management to avoid harming local ecosystems – provide a resource to communities living on volcanic islands, in regions such as Galapagos, Comoros, Cape Verde and Reunion.

All these regions have hydrogeological layered formations similar to what Attias’ team discovered in Hawai’i. It’s possible that they may also have similar freshwater transport mechanisms.

“Such a mechanism may provide alternative renewable resources of freshwater to volcanic islands worldwide where the impacts of climate change decrease water availability,” the researchers write in their paper.

“Our findings emphasise the importance of recognising offshore submarine freshened/freshwater groundwater in future aquifer modelling to use water resources of volcanic islands.”

The research has been published in Science Advances.

 



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Even Mount Everest, The Tallest Peak in The World, Cannot Escape Microplastics

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Microplastics of our own making are turning up in the rain, wind, soil, and snow of the most remote and mountainous regions on our planet.

First they were found in the French Pyrenees. Then it was the North American Rocky Mountains. Now it’s Nepal’s Sagarmāthā National Park – home of Mount Everest, the tallest peak on Earth.

 

“I didn’t know what to expect in terms of results, but it really surprised me to find microplastics in every single snow sample I analyzed,” says ‘plastic detective’ Imogen Napper from the University of Plymouth. 

“Mount Everest is somewhere I have always considered remote and pristine. To know we are polluting near the top of the tallest mountain is a real eye-opener.”

Given how far and wide microplastics have spread, both on land and in water, the discovery is not particularly surprising, although it’s still shocking.

While a lot of attention has been paid to plastic pollution in the world’s oceans, recent estimates have found nearly as many synthetic microfibres are amassing on land and in freshwater sources, in large part because of our clothing. 

Despite Kathmandu, the nearest major city to Everest, located 160 kilometres (99 miles) away, Mount Everest isn’t free of microplastics. A new analysis of the region’s snow and stream water reveals the highest altitude microplastics have ever been recorded.

In each and every snow sample collected during a 2019 expedition, a significant concentration of microplastics was found in the lab – more so than other samples taken from mountainside streams, possibly because these waters were moving quickly and were regularly diluted by melt. 

 

Everest Base Camp was particularly polluted. This is where the majority of climbers spend time, sometimes for a month or longer, and even those that are courteous of their waste are probably contributing to the problem unknowingly. 

The tiny plastic pieces collected for the study were smaller than 5 millimetres and were mainly made of polyester and acrylic fibres, as well as some nylon.

These are the very polymers used to make most outdoor clothing, which needs to be waterproof and insulated, and sturdy outdoor gear, like tents, ropes, and flags.

“Subsequently,” the authors write, “it is highly suspected that these [microplastics] originated from performance clothing and equipment used by climbers and trekkers rather than existing macroplastic debris.” 

Mount Everest is sometimes described as ‘the world’s highest junkyard’. For decades, a surging number of annual climbers have left behind remnants of their visit at basecamp and along the mountainside. 

Last year, the Nepalese Army launched a campaign to clean up roughly 10,000 kilograms (22,046 pounds) of waste from the national park, but not all plastic is so easily collected.

 

Instead of coming from food and drink waste, the new study suggests most microplastics are accumulating in the region from stuff climbers take with them when they leave.

“Microplastics haven’t been studied on the mountain before,” says Napper, “but they’re generally just as persistent and typically more difficult to remove than larger items of debris.”

Prior research, for example, has found one simple coat of polyester clothing could release a billion microplastics per year. This means even the most conscientious environmental climber could be shedding plastics into the environment even as they reduce, reuse, and recycle larger items of waste. 

There’s also the problem of wind, which we’ve only just come to realise. Recent findings reveal microplastics are being carried to some of the most remote regions on Earth by strong currents of air, and this might explain some of the pollution found near base camp.

Mount Everest, after all, is a windy place, but in turn that also means any plastics deposited here are probably blown around even further.

Scientists still don’t know what these tiny particles of plastic are actually doing to human health or the health of our ecosystems. While we’re probably consuming over 70,000 microplastics a year at least, scientists still are not sure at what threshold this pollution becomes toxic or what the subsequent harms may be.

 

While the research found fewer microplastics in the water surrounding Mount Everest, it’s entirely possible that even these lower concentrations could be consumed by locals who reside downstream.

As a result, the authors call for more samples and analysis so we can better understand this potentially crucial issue. 

Figuring a way to clean up these tiny plastics is a whole other problem. Especially when the highest ones are 8,440 metres (27,690 feet) above sea level.

“These are the highest microplastics discovered so far,” says Napper. “While it sounds exciting, it means that microplastics have been discovered from the depths of the ocean all the way to the highest mountain on Earth.” 

“With microplastics so ubiquitous in our environment, it’s time to focus on informing appropriate environmental solutions. We need to protect and care for our planet.”

The study was published in Cell Press.

 



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Mysterious ‘Dark River’ May Flow For 1,000 Kilometres Below Greenland, Scientists Say

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A giant underground river fed by melting ice could be running in a state of perpetual darkness far below the surface of Greenland, according to new research.

Nicknamed the ‘Dark River’, this hypothetical waterway – if it truly exists, that is – may stretch for 1,000 kilometres (620 miles), flowing from the deep interior of Greenland all the way to Petermann Fjord in the country’s northwest.

 

“The results are consistent with a long subglacial river,” says ice sheet modeller Christopher Chambers from Hokkaido University in Japan, “but considerable uncertainty remains.”

010 greenland river 1The suggested valley and possible river. (Chambers et al., The Cryosphere, 2020)

That uncertainty largely stems from significant gaps in radar data from aerial surveys above the Greenland ice sheet, which have over the years detected fragmented glimpses of what looks like a giant, subglacial valley system extending below large parts of Greenland.

Numerous studies in the past couple of decades have suggested such trenches, valleys, or “mega-canyons” could lie hidden in the subglacial environment, and have also floated the idea that liquid water might flow at the bottom of the features.

However, due to gaps in the data – given the sparsity of airborne flights mapping these deep contours – it’s not known if all the valleys are connected in one long, snaking river, or merely segments of disconnected phenomena, let alone how water might behave down there.

“We don’t know how much water, if any, is available to flow along the valley, and if it does indeed exit at Petermann Fjord or is refrozen, or escapes the valley, along the way,” Chambers says.

 

In a new study, designed as a ‘thought experiment’, Chambers and his team explored the hypothetical possibility that the valley isn’t broken up into separate pieces, but runs continuously in one long river.

Such a possibility is plausible, they say, given the segmentation seen in modelling before now might be an illusion – phantom elevations resulting from misleading modelling in data-sparse regions, rather than territorial features.

“The rises occur where data are interpolated to fill in gaps between where radar has obtained reliable data,” the authors write in their new paper. “This suggests that the valley rises may not be real.”

In the new modelling, the researchers assumed the Dark River is indeed a continuous feature. Based on that scenario, the simulations suggested the waterway flows from the centre of Greenland out to the sea, with liquid water traversing the uninterrupted pathway.

“Along its length, the path of the valley progresses gradually down an ice surface slope, causing a lowering of ice overburden pressure that could enable water flow along its path,” the team writes.

While the findings remain hypothetical for now, the researchers think that future aerial surveys might one day be able to confirm the simulations.

If so, it wouldn’t just tell us the Dark River is real, but would also mean we’ve reached a new level of being able to model the behaviour of the Greenland ice sheet – a hugely complex and mysterious body predicted to have a vast impact on future sea level rise.

The findings are reported in The Cryosphere.

 



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Invisible Air Rivers in The Sky Have Been Leaving Giant Holes in Antarctic Ice

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It appeared in 1973, seemingly out of nowhere: a hole in the sea ice off the coast of Antarctica. But this was no ordinary hole. It was so big it could swallow California.

The mysterious opening remained in place for the following three winters. Then it seemed to largely disappear before emerging again in 2017, with a giant maw the size of Maine.

 

This giant hole with a sometimes state-sized appetite is what’s called a polynya – an area of open water surrounded by sea ice, kind of like the opposite of an iceberg.

But the mysterious Weddell Polynya – occurring above the oceanic plateau of Maud Rise, in the Weddell Sea waters of the Southern Ocean – is a rather extreme example of this environmental phenomenon. Why it opens up so dramatically and yet so infrequently has long puzzled scientists.

Last year, researchers suggested that it required the coincidence of a range of climate anomalies all coming together at the same time for the Weddell Polynya to open up with such abandon.

Another study from 2019, led by atmospheric scientist Diana Francis, proposed what one such anomaly was: scars from severe cyclones produced by atmospheric circulation, which can pull floating sea ice in opposite directions and away from the eye of the storm, creating the giant opening.

Francis, now a senior scientist at Khalifa University, UAE, has just led a new study that sheds light on another, related contributor to the phenomenon that’s been overlooked until now: atmospheric rivers of warm, moist air.

 

In the new research, Francis and her team analysed atmospheric data going back to the 1970s, and found that these ‘rivers in the sky’ likely played a “crucial role” in the formation of the Weddell Polynya events of 1973 and 2017, with strong, persistent flows evident in the days preceding both occurrences.

“I was surprised to see an almost immediate melt in the sea ice covered by the atmospheric rivers during the coldest months of the year in Antarctica,” Francis told Nature Middle East.

The researchers say that atmospheric circulation transported a belt of warm, moist air all the way from the coast of South America to the polar region, inducing melting through a combination of effects, including: the release of heat in the air mass; a localised greenhouse effect created by water vapour; and contributions to cyclone dynamics.

“The atmospheric rivers also make the storms more intense because they provide more water vapour. They are linked, not independent,” Francis explained to New Scientist.

It’s unlikely to be the last word on what gives rise to the Weddell Polynya’s monumental meltdowns, but the new insights do broaden our understanding of what’s making the giant hole appear.

Given both atmospheric rivers and cyclones are predicted to increase in severity with global warming, this strange opening off the coast of Antarctica is something we might observe more often, but we’ll have to wait and see.

The findings are reported in Science Advances.

 



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The Ice on Jupiter’s Moon Europa Could Be Literally Glowing in The Dark, Study Hints

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Europa beckons. This distant, icy orb may be only one of Jupiter’s almost 80 known moons, but it’s what’s inside that counts – and what’s inside Europa is predicted to be very special indeed.

 

Under Europa’s icy surface, scientists predict the existence of a giant, hidden ocean: a vast reservoir of water that could represent one of our best chances of finding life in the Solar System.

But Europa isn’t just a shining hope for discovering life beyond Earth. It may be bright for other reasons, too – a moon that literally glows in the dark, according to new research.

In a new study, a team led by physicist Murthy Gudipati from Caltech and NASA’s Jet Propulsion Laboratory suggest that radiation from Jupiter’s magnetic field could induce glowing in the icy surface covering Europa, due to reactions with the chemistry of the ice.

“Europa’s surface continuously experiences high fluxes of charged particles due to the presence of Jupiter’s strong magnetic field,” the researchers explain in their paper.

“These high-energy charged particles, including electrons, interact with the ice- and salt-rich surface, resulting in complex physical and chemical processes.”

Given we don’t fully understand the chemical make-up of Europa’s ice cover yet, just what these processes would look like isn’t clear, and neither the Keck Observatory in Hawaii nor the Hubble Space Telescope have recorded this hypothetical glow occurring before now.

 

Sometime in the next decade, though, we might get a better look, when NASA’s Europa Clipper spacecraft visits the moon, and has a chance to witness the phenomenon, called electron-stimulated luminescence, up close.

For now, though, we can simulate what it might look like with terrestrial proxies, mimicking both the ice of Europa and the high-energy electron radiation of Jupiter.

In a range of experiments in the lab, Gudipati’s team cooled cores of water ice in an aluminium tube, taking the ice down to a temperature of ~100 K (–173.15 °C or –279.67 °F), and subjecting it to pulses of electron radiation.

010 europa jupiter 2Visible glowing from the irradiated ice core in lit, dimmed, and dark conditions. (Gudipati et al., Nature Astronomy, 2020)

When they did this, the ice emitted a glow, but the intensity of the illumination depended on what kinds of non-ice chemicals were present in the water.

“Europa ice analogues emit characteristic spectral signatures in the visible region when exposed to high-energy electron radiation,” the authors write.

“We found that the presence of sodium chloride and carbonate strongly quenched, while epsomite enhanced, the radiation-induced ice glow.”

 

Beyond suggesting a fascinating hypothesis – that Europa may be continuously glowing in the dark, although we’re so far away we can’t detect it – the findings could pave the way for new methods to study the icy moon.

Specifically, it’s possible that Europa Clipper’s imaging systems will be able to observe the glow from orbit (about 50 kilometres or 30 miles above the surface), and in analysing the spectra, shed new light on the chemical composition of the moon’s ice, distinguishing non-ice material from regions of pure water-ice.

In addition to helping future studies of Europa, the same techniques could lead to new ways of analysing other Jovian moons too – such as Io and Ganymede – although the researchers concede the wonderful weirdness at work here may turn out to be a one-off.

“Owing to the unique radiation environment and rich geological and compositional diversity on its surface, the night-time ice glow occurring on Europa may be very unique and unlike any other phenomenon in our Solar System,” the researchers conclude.

The findings are reported in Nature Astronomy.

 



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Ancient Meteorite Hints Mars Had Water Before There Was Life on Earth

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We know that Mars was once much wetter than it is now, but the questions of when water formed and evaporated away are much more difficult to answer.

A new study now suggests that water was present on the Red Planet some 4.4 billion years ago, much earlier than previously thought.

 

That’s based on an analysis of a meteorite named NWA 7533, picked up in the Sahara Desert and thought to have originated on Mars billions of years ago. The oxidation of certain minerals inside the meteorite hints at the presence of water.

The findings could push back the estimated date of water formation on Mars some 700 million years, from the 3.7-billion-years-ago timeframe that has been the general consensus up until now. The research could also offer up some insights into how planets form in the first place.

“I study minerals in Martian meteorites to understand how Mars formed and its crust and mantle evolved,” says planetary scientist Takashi Mikouchi from the University of Tokyo in Japan.

“This is the first time I have investigated this particular meteorite, nicknamed ‘Black Beauty’ for its dark colour. Our samples of NWA 7533 were subjected to four different kinds of spectroscopic analysis, ways of detecting chemical fingerprints. The results led our team to draw some exciting conclusions.”

Planetary scientists are keenly interested in the story of water on planets and on moons. One of the big unknowns is whether water gets added to a planetary body after it forms, through the impacts of asteroids and comets, or whether it occurs naturally during the planet formation process.

 

Ancient rocks like NWA 7533 can help scientists peer back in time and find out, as they record impact events on the planet they come from, and capture some of the mineral and chemical composition of the surface when they are formed.

In this case, it’s the oxidation that’s the tell-tale sign of water. With certain fragments inside NWA 7533 dated to 4.4 billion years ago, it’s the oldest record we’ve got of Mars (which may be why a single gram of this meteorite can fetch as much as US$10,000).

“Igneous clasts, or fragmented rock, in the meteorite are formed from magma and are commonly caused by impacts and oxidation,” says Mikouchi. “This oxidation could have occurred if there was water present on or in the Martian crust 4.4 billion years ago during an impact that melted part of the crust.”

Such an early appearance suggests that water actually was around when Mars formed and that in turn plays into research into planetary formation in general. With water comes life, which is one reason scientists are so eager to track it down around the Universe. For comparison, we know that the earliest traces of life on Earth date to at least 3.5 billion years ago.

The close study of Mars continues as experts try and figure out when water was present and what form it might have taken. One recent study put forward the idea that both liquid water and surface ice could have existed on the Red Planet at the same time.

The team’s findings also suggest that the chemical make-up of the Martian atmosphere at this time – including high levels of hydrogen – could have made the planet warm enough for water to melt and life to exist, even though the Sun would have been younger and fainter during this period.

“Our analysis also suggests such an impact would have released a lot of hydrogen, which would have contributed to planetary warming at a time when Mars already had a thick insulating atmosphere of carbon dioxide,” says Mikouchi.

The research has been published in Science Advances.

 



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Scientists Say This New Rice-Cooking Hack Removes Arsenic But Keeps The Nutrients

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Rice is one of the most widely consumed foods in the world. It’s also very high in arsenic compared to most other foods, absorbing about 10 times as much toxic inorganic arsenic as other cereal crops.

 

This is mostly due to the way rice is grown in flooded rice fields, which makes it easier for the crop to absorb the carcinogenic compounds naturally present in the soil. Contaminated groundwater is considered the greatest threat to public health in terms of arsenic exposure, in part because of its use in irrigation for rice production.

Human awareness of arsenic toxicity dates back thousands of years, but awareness of the same dangers via rice consumption is a more recent development.

While some countries have regulations designed to place limits on exposure to inorganic arsenic through rice consumption, many Asian countries (where rice consumption is high) have no such rules.

Even in countries like the UK and US that do have such guidelines, there could be unseen risks, particularly to young children, who are more susceptible to arsenic exposure.

One study earlier in the year tested 55 rice varieties sold in the UK, finding that over half contained levels of arsenic higher than regulations permit for babies and children under five years of age, while another found an association between rice consumption and mortality risk due to cardiovascular disease.

 

“There are genuine concerns amongst the population about eating rice due to arsenic,” says soil scientist Manoj Menon from the University of Sheffield in the UK.

Fortunately, for several years it’s been understood that the levels of inorganic arsenic in rice can be reduced in various ways, via washing or rinsing, or using different cooking methods. However, some of these can also lower the levels of nutrients in rice, which also isn’t desirable.

In a new study, Menon and his team investigated different rice-cooking methods to see which offered the best way of reducing arsenic while preserving nutrients.

They examined four processes, all of which involved cooking rice via the absorption method, using either unwashed rice, washed rice, pre-soaked rice, or parboiled rice.

When they analysed the results, they found the parboiling with absorption method (PBA) reduced the most arsenic from the rice, while preserving its nutrients.

010 rice cooking 2(Menon et al., Science of The Total Environment, 2020)

To do this at home, the researchers say you can bring water to the boil (four cups of fresh water for every cup of raw rice). Then, add rice and boil for another 5 minutes. Next, discard the water (which has now removed much of the arsenic that was in the rice), and add more fresh water (two cups for each cup of rice). Finally, cover the rice with a lid, and cook on a low to medium heat until the water has been absorbed.

“With our new method we are able to significantly reduce the arsenic exposure while reducing the loss of key nutrients,” Menon says.

 

“We highly recommend this method while preparing rice for infants and children as they are highly vulnerable to arsenic exposure risks.”

According to the researchers, this technique removes about 54 percent of the inorganic compound in brown rice, and about 73 percent in white rice, while generally retaining the most amount of the nutrients phosphorous, potassium, magnesium, zinc and manganese.

In addition to arsenic removal and nutrient preservation, the researchers say the PBA method uses less water, energy and cooking time than other cooking methods that can remove the arsenic, such as using and discarding excess water (which also removes more nutrients).

The researchers acknowledge their experiment ought to be repeated in different environments, using different kinds of regional rice types, and different levels of water quality. But it’s a good first step.

The findings are reported in Science of The Total Environment.

 



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Man Almost Dies From an Allergic Reaction to Cold Air After a Shower

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Stepping out of a hot shower into a cold bathroom almost killed a Colorado man, who had developed a serious allergic reaction to cold temperatures.

The 34-year-old old man collapsed after getting out of the shower, and his family found him on the floor, according to a report of the case published October 27 in The Journal of Emergency Medicine.

 

The man was struggling to breathe and his skin was covered in hives. He was experiencing a life-threatening, whole-body allergic reaction known as anaphylaxis.



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