Space weather discovery puts 'habitable planets' at risk

A discovery that links stellar flares with radio-burst signatures will make it easier for astronomers to detect space weather around nearby stars outside the Solar System. Unfortunately, the first weather reports from our nearest neighbour, Proxima Centauri, are not promising for finding life as we know it.

Astronomers have recently found there are two 'Earth-like' rocky planets around Proxima Centauri, one within the 'habitable zone' where any water could be in liquid form. 

Proxima Centauri is just 4.2 light years from Earth.

But given Proxima Centauri is a cool, small red-dwarf star, it means this habitable zone is very close to the star; much closer in than Mercury is to our Sun.

Some present research shows is that this makes the planets very vulnerable to dangerous ionising radiation that could effectively sterilise the planets. astronomers have for the first time shown a definitive link between optical flares and radio bursts on a star that is not the Sun. The finding, published today in The Astrophysical Journal, is an important step to using radio signals from distant stars to effectively produce space weather reports.

 Astrophysical Journal (2020). DOI: 10.3847/1538-4357/abca90

https://phys.org/news/2020-12-space-weather-discovery-habitable-pla...

Manmade mass now outweighs life on Earth: study

For the first time in history manmade materials now likely outweigh all life on Earth, scientists said recently in research detailing the "crossover point" at which humanity's footprint is heavier than that of the natural world.

The weight of roads, buildings and other constructed or manufactured materials is doubling roughly every 20 years, and authors of the research said it currently weighed 1.1 teratonnes (1.1 trillion tonnes).

As mankind has ramped up its insatiable consumption of natural resources, the weight of living biomass—trees, plants and animals—has halved since the agricultural revolution to stand at just 1 teratonne currently, the study found.

Estimating changes in global biomass and manmade mass since 1990, the research showed that the mass of human-produced objects stood at just three percent of the weight of biomass at the start of the 20th century.

But since the post-World War II global production boom, manufacturing has surged to the extent that humans now produce the equivalent of the weight of every person on Earth every week on average.

Global human-made mass exceeds all living biomass, Nature (2020). DOI: 10.1038/s41586-020-3010-5 , www.nature.com/articles/s41586-020-3010-5

https://phys.org/news/2020-12-manmade-mass-outweighs-life-earth.htm...

Why did Mount Everest's height change?

The world's highest mountain is now officially a little higher. China and Nepal presented a new official figure of 8,848.86 meters (29,031.69 feet) above sea level. 

China and Nepal agreed this week on a new standard height for Mount Everest. Geological changes, the complicated business of measuring a mountain and varying criteria for determining the world's highest peak will likely ensure the question isn't settled for good.

The mountain's height changes. The movement of tectonic plates can lift it up ever so gradually, while earthquakes can bring it down.

The countervailing forces may help maintain a degree of stability over time.

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There's more than one way to measure a mountain.

Last year, a Nepalese team set up a satellite navigation marker on Everest's peak to gauge its exact position via GPS satellites. A Chinese team undertook a similar mission this spring, though it used the Chinese-made Beidou constellation of navigation satellites, along with other equipment.

At the same time, Nepalese crews took measurements with modern, laser-equipped versions of instruments called theodolites, first used to gauge the mountain's height in 1856 by measuring angles using trigonometry.

The Nepalese team also used ground penetrating radar to measure the amount of snow and ice that sits on top of its highest rock.

The new height is 0.86 meters (more than 2 feet) above the higher of the countries' two previous figures, that given by Nepal. The two had diverged for year over the mountain's actual height.

Measuring the height above sea level has always been tricky because ocean levels vary considerably depending on tides, magnetism and other factors. Rising sea levels are creating another factor for future measurements.

How high above sea level is just one way of measuring a mountain's height. One reason Everest wins the prize is that its base sits high up on already lofty foothills.

As measured from the Earth's core, Ecuador's Mount Chimborazo is the world's highest, standing more than 2,072 meters (6,800 feet) above Everest. Because the Earth bulges in the middle, mountains along the equator are farther from the core.

Measuring from the foot of the mountain to the peak, Hawaii's Mauna Kea is the tallest. Most of it, however, is under the sea.

https://phys.org/news/2020-12-mount-everest-height.html?utm_source=...

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Pesticides in contact with plastic mulch take longer to degrade

The use of plastic mulch (plastic covering on crop lines) is a widespread technique used in agricultural regions in order to increase the profitability of the crops. According to the European Commission, 100,000 tons of plastic mulch was used per year in the European Union in 2016. Taking these figures into account and the fact that after the harvest some plastic usually remains in the soil, the accumulation of plastic in territories of intensive agriculture is an environmental problem that is of concern in the sector and also for public administration.

Scientists discover how COVID-19 virus causes multiple organ failure in mice

 Researchers  created a version of COVID-19 in mice that shows how the disease damages organs other than the lungs. Using their model, the scientists discovered that the SARS-CoV-2 virus can shut down energy production in cells of the heart, kidneys, spleen and other organs.

Understanding how this virus can hijack our cells might eventually lead to new ways to prevent or treat the organ failure that can accompany COVID-19 in humans. 

Research in humans has suggested that SARS-CoV-2 can circulate through the bloodstream to reach multiple organs. So in the UCLA experiment, the researchers first engineered mice to have the human version of ACE2 in the heart and other vital organs. Then, they infected half of the animals by injecting SARS-CoV-2 into their bloodstreams. Over the following days, the researchers tracked the animals’ overall health and analyzed how levels of certain genes and proteins in their bodies changed.

Within seven days, all of the mice with COVID-19 had stopped eating and were completely inactive, and had lost, on average, about 20% of their body weight. Animals that had been engineered to carry the human ACE2 protein but had not been infected with the virus, on the other hand, did not lose a significant amount of weight.

Moreover, the COVID-19 infected animals had altered levels of immune cells, swelling of the heart tissue and wasting away of the spleen — all symptoms that have been observed in people who are critically ill with COVID-19.

The research team also looked at which genes were turned on and off in the mice infected with SARS-CoV-2, and they discovered other signs of disease. Common molecular processes that help cells generate energy — through mechanisms known as the tricarboxylic acid cycle, or TCA cycle, and electron transport chain — were shut off in the heart, kidney, spleen and lungs.

If a virus snuffs out the energy-generating pathways in multiple organs of the body, that’s going to really wreak havoc.

The study also revealed that some changes were long-lasting throughout the organs in mice with COVID-19. In addition to temporarily altering which genes were turned on and off in some cells, the virus made epigenetic changes — chemical alterations to the structure of DNA that cause more lasting effects. This could explain why, in some people with COVID-19, symptoms persist for weeks or months after their bodies are rid of the virus.

https://newsroom.ucla.edu/releases/covid-19-multiple-organ-failure-...

https://researchnews.cc/news/4027/Scientists-discover-how-COVID-19-...

These simple steps can help prevent heat-related fatalities

Dogs Probably Don't Understand Us as Well as We Think, Brain Scans Reveal

Dogs may never learn that every sound of a word matters

https://www.sciencealert.com/dogs-may-not-actually-understand-us-as...

This Teen's Brilliantly Simple Explainer on Quantum Mechanics Just Won a Global Prize

Blocking protein restores strength, endurance in old mice, study finds

Muscle loss during aging is known as sarcopenia, and it accounts for billions of dollars of health care expenditures  each year as people lose the ability to care for themselves, experience more falls and become increasingly less mobile. It is due to changes in muscle structure and function: The muscle fibers shrink and the number and function of the cellular powerhouses known as mitochondria dwindle.

Blocking the activity of a single protein in old mice for one month restores mass and strength to the animals' withered muscles and helps them run longer on a treadmill, according to a study by researchers. Conversely, increasing the expression of the protein in young mice causes their muscles to atrophy and weaken.

The improvement is really quite dramatic. The old mice are about 15% to 20% stronger after one month of treatment, and their muscle fibres look like young muscle. Considering that humans lose about 10% of muscle strength per decade after about age 50, this is quite remarkable.

The protein hasn't previously been implicated in aging. The researchers show that the amount of the protein, called 15-PGDH, is elevated in old muscle and is widely expressed in other old tissues. Experiments they conducted in human tissue raise hopes for a future treatment for the muscle weakness that occurs as people age.

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Prostaglandin E2 levels are regulated by 15-PGDH, which breaks down prostaglandin E2. The researchers used a highly sensitive version of mass spectrometry, a method for differentiating closely related molecules, to determine that compared with young mice, the 15-PGDH levels are elevated in the muscles of older animals, and the levels of prostaglandin E2 are lower.

They found a similar pattern of 15-PGDH expression in human muscle tissues, as those from people in their 70s and early 80s expressed higher levels than those from people in their mid-20s.

"We knew from our previous work that prostaglandin E2 was beneficial for regeneration of young muscles.

"Inhibition of prostaglandin-degrading enzyme 15-PGDH rejuvenates aged muscle mass and strength" Science (2020). science.sciencemag.org/lookup/ … 1126/science.abc8059

https://medicalxpress.com/news/2020-12-blocking-protein-strength-mi...

Researchers identify the physical mechanism that can kill bacteria with gold nanoparticles

Finding alternatives to antibiotics is one of the biggest challenges facing the research community. Bacteria are increasingly resistant to these drugs, and this resistance leads to the deaths of more than 25,000 around the world. Now, a multidisciplinary team of researchers have discovered that the mechanical deformation of bacteria is a toxic mechanism that can kill bacteria with gold nanoparticles. The results of this research have been published in the journal Advanced Materials and are a breakthrough in researchers' understanding the antibacterial effects of nanoparticles and their efforts to find new materials with bactericide properties.

Since the times of Ancient Egypt, gold has been used in a range of medical applications and, more recently, as for diagnosing and treating diseases such as cancer. This is due to the fact that gold is a chemically inert material, that is, it does not react or change when it comes into contact with an organism. Amongst the scientific community, nanoparticles are known for their ability to make tumors visible and for their applications in nanomedicine.

This new research shows that these chemically inert nanoparticles can kill bacteria thanks to a physical mechanism that deforms the cell wall. To demonstrate this, the researchers have synthesized in the laboratory gold nanoparticles in the shape of an almost perfect sphere and others in the shape of stars, all measuring 100 nanometres (8 times thinner than a hair). The group analyzed how these particle interact with living bacteria. Researchers found that the bacteria become deformed and deflate like a ball that is having the air let out before dying in the presence of these nanoparticles as if the cell wall had spontaneously exploded. 

The scientists thought that a physical mechanism might be responsible for the death of the bacteria. Consequently, they carried out aa numerical simulations to analyze how a homogenous layer of individual nanoparticles could apply sufficient mechanical tension to the cell wall of the bacteria that it ends up breaking seemingly by stretching, like a balloon that is inflated from different points until it exploded.

To confirm this hypothesis, the researchers created an artificial model of a bacterial cell membrane to evaluate its response when it entered into contact with the 100 nm gold nanoparticles. They found that the model spontaneously contracted until it completely collapsed, thus proving the hypothesis that nanoparticles apply a mechanical stretch on the cell membrane of the bacteria.

Denver P. Linklater et al, Antibacterial Action of Nanoparticles by Lethal Stretching of Bacterial Cell Membranes, Advanced Materials (2020). DOI: 10.1002/adma.202005679

https://phys.org/news/2020-12-physical-mechanism-bacteria-gold-nano...

** The greening of the Earth is approaching its limit

When plants absorb this gas to grow, they remove it from the atmosphere and it is sequestered in their branches, trunk or roots. An article published today in Science shows that this fertilizing effect of CO2 is decreasing worldwide, according to the text co-directed by Professor Josep Peñuelas of the CSIC at CREAF and Professor Yongguan Zhang of the University of Nanjin, with the participation of CREAF researchers Jordi Sardans and Marcos Fernández. The study, carried out by an international team, concludes that the reduction has reached 50% progressively since 1982 due basically to two key factors: the availability of water and nutrients.

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COVID-19 and other pandemics are the effects of our negative impact...

There is increasing awareness that the COVID-19 pandemic is the consequence of environmental and societal crises. A new paper just published in the scientific journal Science of the Total Environment by international research fellows of the Konrad Lorenz Institute for Evolution and Cognition Research (KLI), an Austrian independent center for advanced studies in the life and sustainability sciences, presents an interdisciplinary approach to analyze the COVID-19 pandemic as a phenomenon affecting the diversity of all spheres of the total environment.

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Bad news for fake news: New research helps combat social media misi...

Rice University researchers have discovered a more efficient way for social media companies to keep misinformation from spreading online using probabilistic filters trained with artificial intelligence.

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Researchers shed new light on mysteries behind the light emission o...

A team of researchers from the NYU Abu Dhabi's (NYUAD) Smart Materials Lab (SML) led by Professor of Chemistry Panče Naumov has conducted a thorough review of the scientific literature surrounding the natural production of light, called bioluminescence, and developed conclusions that will help others in the field direct their research to uncover the mysteries behind this fascinating natural phenomenon.

Distinct Microbiome and Metabolites Linked with Depression

Since its completion in November 1963, the Telescope had been used for radar astronomy and radio astronomy, and had been part of the Search for extraterrestrial intelligence (SETI) program. It was also used by NASA for Near-Earth object detection.
Arecibo joins with telescopes in Europe and with the Russian Radio Astron satellite to form the largest telescope ever – 20 times the size of the Earth. Arecibo continues to obtain orbit refinement of potentially hazardous near-Earth asteroids (PHAs) to identify possible future Earth impactors.
It has several acheivements since it started working
http://www.naic.edu/about/accomplishments.html#:~:text=Arecibo%20jo....

Scientists build whole functioning thymus from human cells

Researchers at the Francis Crick Institute and University College London have rebuilt a human thymus, an essential organ in the immune system, using human stem cells and a bioengineered scaffold. Their work is an important step towards being able to build artificial thymi which could be used as transplants.

The thymus is an organ in the chest where T lymphocytes, which play a vital role in the immune system, mature. If the thymus does not work properly or does not form during foetal development in the womb, this can lead to diseases such as severe immunodeficiency, where the body cannot fight infectious diseases or cancerous cells, or autoimmunity, where the immune system mistakenly attacks the patient's own healthy tissue.

In their proof-of-concept study, published in Nature Communications today, the scientists rebuilt thymi using stem cells taken from patients who had to have the organ removed during surgery. When transplanted into mice, the bioengineered thymi were able to support the development of mature and functional human T lymphocytes.

While researchers have previously rebuilt other organs or sections of organs, this is the first-time scientists have successfully rebuilt a whole working human thymus. 

Campinoti, S et al. (2020). Reconstitution of a functional human thymus by postnatal stromal progenitor cells and natural whole-organ scaffolds. Nature Communications, DOI: 10.1038/s41467-020-20082-7

https://medicalxpress.com/news/2020-12-scientists-functioning-thymu...

Some droughts during the Indian monsoon are due to unique North Atl...

A team of researchers from the Indian Institute of Science and Cotton University has found that some droughts during monsoon season in India are due to unique North Atlantic disturbances. In their paper published in the journal Science, the group describes their study of weather patterns in South Asia over the past century and what it showed about monsoon season droughts.

P. J. Borah et al. Indian monsoon derailed by a North Atlantic wavetrain, Science (2020). DOI: 10.1126/science.aay6043

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Current pace of action on climate change is "unthinkable" state ex ...

Justifiable pride can be taken in the incremental accomplishments of international climate change cooperation, but it is "unthinkable" to continue at the current pace. The global response to climate change is completely insufficient and leaves the world on a "road to hell".

Climate Policy (2020). DOI: 10.1080/14693062.2020.1860567

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Black holes gain new powers when they spin fast enough

General relativity is a profoundly complex mathematical theory, but its description of black holes is amazingly simple. A stable black hole can be described by just three properties: its mass, its electric charge and its rotation or spin. Since black holes aren't likely to have much charge, it really takes just two properties. If you know a black hole's mass and spin, you know all there is to know about the black hole.

This property is often summarized as the no-hair theorem. Specifically, the theorem asserts that once matter falls into a black hole, the only characteristic that remains is mass. You could make a black hole out of a sun's worth of hydrogen, chairs or those old copies of National Geographic from Grandma's attic, and there would be no difference. Mass is mass as far as general relativity is concerned. In every case, the event horizon of a black hole is perfectly smooth, with no extra features. "The balck holes have no hair."

But with all its predictive power, general relativity has a problem with quantum theory. This is particularly true with black holes. If the no-hair theorem is correct, the information within an object is destroyed when it crosses the event horizon. Quantum theory says that information can never be destroyed. So the valid theory of gravity is contradicted by the valid theory of the quanta. This leads to problems such as the firewall paradox, which can't decide whether an event horizon should be hot or cold.

Several theories have been proposed to solve this contradiction, often involving extensions to relativity. The difference between standard relativity and these modified theories can only be seen in extreme situations, making them difficult to study observationally. But a new paper in Physical Review Letters shows how they might be studied through the spin of a black hole.

Many modified relativity theories have an extra parameter not seen in the standard theory. Known as a massless scalar field, it allows Einstein's model to connect with quantum theory  in a way that isn't contradictory. In this new work, the team looked at how such a scalar field connects to the rotation of a black hole. They found that at low spins, a modified black hole is indistinguishable from the standard model, but at high rotations, the scalar field allows a black hole to have extra features. In other words, in these alternative models, rapidly rotating black holes can have hair.

The hairy aspects of rotating black holes would only be seen near the event horizon itself, but they would also affect merging black holes. As the authors point out, future gravitational wave observatories should be able to use rapidly rotating black holes to determine whether an alternative to general relativity is valid.

Einstein's theory of general relativity has passed every observational challenge so far, but it will likely break down in the most extreme environments of the universe. Studies such as this show how we might be able to discover the theory that comes next.

 Alexandru Dima et al. Spin-Induced Black Hole Spontaneous Scalarization, Physical Review Letters (2020). DOI: 10.1103/PhysRevLett.125.231101

https://phys.org/news/2020-12-black-holes-gain-powers-fast.html?utm...

How epigenetic switches control gene expression

Scientists at Tokyo Institute of Technology have deciphered how to quantitatively assess the effects of specific epigenetic changes on the rate of transcription by developing a mathematical model. Using their method, they successfully generated reconstituted chromatin-bearing histone modifications in vitro. Their study published in Nucleic Acids Research provides an accurate quantitative approach for understanding how site-specific changes to histone proteins impact the accessibility of chromatin and gene expression levels.

Masatoshi Wakamori et al, Quantification of the effect of site-specific histone acetylation on chromatin transcription rate, Nucleic Acids Research (2020). DOI: 10.1093/nar/gkaa1050

https://phys.org/news/2020-12-epigenetic-gene.html?utm_source=nwlet...

Researchers find why 'lab-made' proteins have unusually high temperature stability

Bioengineers have found why proteins that are designed from scratch tend to be more tolerant to high temperatures than proteins found in nature.

Rie Koga et al, Robust folding of a de novo designed ideal protein even with most of the core mutated to valine, Proceedings of the National Academy of Sciences (2020). DOI: 10.1073/pnas.2002120117

https://phys.org/news/2020-12-lab-made-proteins-unusually-high-temp...

Study sheds light on diabetes and COVID interaction
NASHVILLE, TN.- COVID-19 has been linked to cases of new-onset diabetes, diabetes-related emergencies and a higher death rate among diabetes patients. While this suggests that SARS-CoV-2, the virus that causes COVID-19, may infect and damage the insulin-producing beta cells of the pancreas, that does not appear to be the case, according to a report by researchers at Vanderbilt University Medical Center published Dec. 1 in the journal Cell Metabolism. “This is important information in terms of understanding the interaction of diabetes and SARS-CoV-2 and COVID-19,” said Katie Coate, PhD, who led the study with Jeeyeon Cha, MD, PhD. “There are other potential pathways for how SARS-CoV-2 infects cells, and these are just beginning to be described or are as yet undiscovered

Charles Darwin was right about why insects are losing the ability to fly

Most insects can fly.

Yet scores of species have lost that extraordinary ability, particularly on islands.

On the small islands that lie halfway between Antarctica and continents like Australia, almost all the insects have done so.

Flies walk, moths crawl.

Of course, Charles Darwin knew about this wing loss habit of island insects. He and the famous botanist Joseph Hooker had a substantial argument about why this happens. Darwin's position was deceptively simple. If you fly, you get blown out to sea. Those left on land to produce the next generation are those most reluctant to fly, and eventually evolution does the rest. 

But since Hooker expressed his doubt, many other scientists have too.

In short, they have simply said Darwin got it wrong.

Yet almost all of these discussions have ignored the place that is the epitome of flight loss—those 'sub-Antarctic' islands. Lying in the 'roaring forties' and 'furious fifties', they're some of the windiest places on Earth.

If Darwin really got it wrong, then wind would not in any way explain why so many insects have lost their ability to fly on these islands.

Using a large, new dataset on insects from sub-Antarctic and Arctic islands, Monash University researchers examined every idea proposed to account for flight loss in insects, including Darwin's wind idea.

Reporting today in Proceedings of the Royal Society B, they show that Darwin was right for this 'most windy of places'. None of the usual ideas (such as those proposed by Hooker) explain the extent of flight loss in sub-Antarctic insects, but Darwin's idea does. Although in a slightly varied form, in keeping with modern ideas on how flight loss actually evolves.

Windy conditions make insect flight more difficult and energetically costly. Thus, insects stop investing in flight and its expensive underlying machinery (wings, wing muscles) and redirect the resources to reproduction.

Wind plays a major but not exclusive role in the prevalence of insect flight loss on remote islands.

 Proceedings of the Royal Society B, rspb.royalsocietypublishing.or … .1098/rspb.2020.2121

https://phys.org/news/2020-12-charles-darwin-insects-ability.html?u...

Expandable Foam Supersizes 3D-Printed Objects - Headline Science

Physicists create time-reversed optical waves

Optics researchers  have developed a new technique to demonstrate the time reversal of optical waves, which could transform the fields of advanced biomedical imaging and telecommunications.

Time reversal of waves in physics doesn't mean traveling back to the future; it describes a special type of wave which can retrace a path backwards through an object, as if watching a movie of the traveling wave, played in reverse.

UQ's Dr. Mickael Mounaix and Dr. Joel Carpenter, together with Dr. Nick Fontaine's team at Nokia Bell Labs, are the first to demonstrate this time reversal of optical waves, using a new device they developed that allows full 3-D control of light through an optical fiber.

Time reversed optical waves by arbitrary vector spatiotemporal field generation 

https://phys.org/news/2020-12-physicists-time-reversed-optical.html...

** Toward imperceptible electronics that you cannot see or feel

Transparent electronics—such as head-up displays that allow pilots to read flight data while keeping their eyes ahead of them—improve safety and allow users to access data while in transit. For healthcare applications, the electronics need to not only be cheap and straightforward to fabricate, but also sufficiently flexible to conform to skin. Silver nanowire networks meet these criteria. However, current methods of development create random nanowire alignment that's insufficient for advanced applications.

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Nanoparticles, from hype to actual clinical product

Ph.D. candidate Jaleesa Bresseleers, of the TU/e department of Biomedical Engineering, investigated a robust and scalable manufacturing process for nanocarriers and their building blocks. With these insights, the road to widely available clinical applications for nanocarriers has become much shorter.

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The moon controls the release of methane in Arctic Ocean

It may not be very well known, but the Arctic Ocean leaks enormous amounts of the potent greenhouse gas methane. These leaks have been ongoing for thousands of years but could be intensified by a future warmer ocean. The potential for this gas to escape the ocean, and contribute to the greenhouse gas budget in the atmosphere, is an important mystery that scientists are trying to solve.

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A young but completely evolved entirely self-made galaxy

So young and already so evolved: Thanks to observations obtained at the Large Binocular Telescope, an international team of researchers coordinated by Paolo Saracco of the Istituto Nazionale di Astrofisica (INAF, Italy) was able to reconstruct the wild evolutionary history of an extremely massive galaxy that existed 12 billion years ago, when the universe was only 1.8 billion years old, less than 13% of its present age. This galaxy, dubbed C1-23152, formed in only 500 million years, an incredibly short time to give rise to a mass of about 200 billion suns. To do so, it produced as many as 450 stars per year, more than one per day, a star formation rate almost 300 times higher than the current rate in the Milky Way. The information obtained from this study will be fundamental for galaxy formation models for objects it for which it is currently difficult to account.

**The moon controls the release of methane in Arctic Ocean

It may not be very well known, but the Arctic Ocean leaks enormous amounts of the potent greenhouse gas methane. These leaks have been ongoing for thousands of years but could be intensified by a future warmer ocean. The potential for this gas to escape the ocean, and contribute to the greenhouse gas budget in the atmosphere, is an important mystery that scientists are trying to solve.

The total amount of methane in the atmosphere has increased immensely over the past decades, and while some of the increase can be ascribed to human activity, other sources are not very well constrained.

A recent paper in Nature Communications even implies that the moon has a role to play.

The moon controls one of the most formidable forces in nature—the tides that shape our coastlines. Tides, in turn, significantly affect the intensity of methane emissions from the Arctic Ocean seafloor.

Researchers noticed that gas accumulations, which are in the sediments within a meter from the seafloor, are vulnerable to even slight pressure changes in the water column. Low tide means less of such hydrostatic pressure and higher intensity of methane release. High tide equals high pressure and lower intensity of the release.

It is the first time that this observation has been made in the Arctic Ocean. It means that slight pressure changes can release significant amounts of methane. This is a game-changer and the highest impact of the study.

Nabil Sultan et al, Impact of tides and sea-level on deep-sea Arctic methane emissions, Nature Communications (2020). DOI: 10.1038/s41467-020-18899-3

https://phys.org/news/2020-12-moon-methane-arctic-ocean.html?utm_so...

Chance played a major role in keeping Earth fit for life

A study by the University of Southampton gives a new perspective on why our planet has managed to stay habitable for billions of years—concluding it is almost certainly due, at least in part, to chance. The research suggests this may shorten the odds of finding life on so-called 'twin-Earths' in the Universe.

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Hibernating lemurs may be the key to cryogenic sleep for human spac...

Science fiction is shifting into reality. With humanity's plans to return to the moon this decade and further ambitions to travel to Mars in the next, we need to figure out how to keep astronauts healthy for these years-long missions. One solution long championed by science fiction is suspended animation, or putting humans in a hibernation-like sleep for the duration of travel time.

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AI can predict Twitter users likely to spread disinformation before...

A new artificial intelligence-based algorithm that can accurately predict which Twitter users will spread disinformation before they actually do it has been developed by researchers from the University of Sheffield.

Improving portraits by adding light after a picture was taken

Recently, Google introduced Portrait Light, a feature on its Pixel phones that can be used to enhance portraits by adding an external light source not present at the time the photo was taken. In a new blog post, Google explains how they made this possible.

In their post, engineers at Google Research note that professional photographers discovered long ago that the best way to make people look their best in portraits is by using secondary flash devices that are not attached to the camera. Such flash devices can be situated by the photographer prior to photographing a subject by taking into account the direction their face is pointing, other light available, skin tone and other factors. Google has attempted to capture those factors with its new portrait-enhancing software. The system does not require the camera phone operator to use another light source. Instead, the software simply pretends that there was another light source all along, and then allows the user to determine the most flattering configuration for the subject.

The engineers explain they achieved this feat using two algorithms. The first, which they call automatic directional light placement, places synthetic light into the scene as a professional photographer would. The second algorithm is called synthetic post-capture relighting. It allows for repositioning the light after the fact in a realistic and natural-looking way.

Both of the algorithms rely on deep-learning networks. Google trained the software using available photographs and by photographing hundreds of portrait shots of 70 people with lights placed in 331 locations and cameras placed at 64 viewpoints. They also employed well-known principles such as the best angles for placing lights relative to the particular features of a person's face.

The software is available in newer Pixel phones. Older camera users can try the new software on the Google Photos online service, while it's built into newer phones. Users can either accept the automatic enhancement provided by their phone or change it manually.

https://ai.googleblog.com/2020/12/portrait-light-enhancing-portrait...

https://techxplore.com/news/2020-12-portraits-adding-picture.html?u...

A Deep Dive On Deepfakes Telling fact from fiction may be harder than you think—a new study from Singapore has found that even people aware of deepfakes have inadvertently shared them online. 

Ahmed (2020) Who Inadvertently Shares Deepfakes? Analyzing the Role of Political Interest, Cognitive Ability, and Social Network Size. https://www.asianscientist.com/2020/12/tech/deepfakes-social-media-...

Spiders in Space

Sleep, Memory and Dreams: Fitting the Pieces Together

https://www.the-scientist.com/videos/whats-in-a-dream-68223?utm_cam...

The bats that wear face masks!

The wrinkle-faced bat covers its face with a flap of skin, seemingly as part of its courtship rituals.

https://www.scientificamerican.com/podcast/episode/this-bat-wears-a...

Embryonic development in a Petri dish

 It would certainly spare mothers the hardships of pregnancy, but mammals do not grow in eggs. In a way, this is also impractical for science. While embryos of fish, amphibians or birds can be easily watched growing, mammalian development evades the gaze of the observer as soon as the embryo implants into the uterus. This is precisely the time when the embryo undergoes profound changes in shape and develops precursors of various organs  a highly complex process that leaves many questions unanswered. But now a research team  succeeded in replicating a central phase of embryonic development in a cell culture approach by growing the core portion of the trunk from mouse embryonic stem cells for the first time. The method recapitulates the early shape-generating processes of embryonic development in the Petri dish. 

A gel provides support and spatial orientation
So far, it has only been possible to grow cell clusters from embryonic stem cells, so-called gastruloids. “Cellular assemblies in gastruloids develop to a similar extent like in our trunk-like structures, but they do not assume the typical appearance of an embryo” says Jesse Veenvliet, one of the two lead authors of the study. “The cell clusters lack the signals that trigger their organization into a meaningful arrangement.”

In the cell culture, the required signal is generated by a special gel that mimics the properties of the extracellular matrix. This jelly-like substance consists of a complex mixture of extended protein molecules that is secreted by cells and is found throughout the body as an elastic filling material, especially in connective tissues. The utilization of this gel is the crucial “trick” of the new method.
Cells with similar properties as in the embryo
After four to five-days, the team dissolved the structures into single cells and analyzed them individually. “Even though not all cell types are present in the trunk-like structures, they are strikingly similar to an embryo of the same age.

https://researchnews.cc/news/4117/Embryonic-development-in-a-Petri-...

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Chameleon-like material spiked with boron comes closer to mimicking brain cells

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Apathy could predict onset of dementia years before other symptoms

Apathy—a lack of interest or motivation—could predict the onset of some forms of dementia many years before symptoms start, offering a 'window of opportunity' to treat the disease at an early stage, according to new research from a team of scientists.

Frontotemporal dementia is a significant cause of dementia among younger people. It is often diagnosed between the ages of 45 and 65. It changes behaviour, language and personality, leading to impulsivity, socially inappropriate behaviour, and repetitive or compulsive behaviours.

A common feature of frontotemporal dementia is apathy, with a loss of motivation, initiative and interest in things. It is not depression, or laziness, but it can be mistaken for them. Brain scanning studies have shown that in people with frontotemporal dementia it is caused by shrinkage in special parts at the front of the brain—and the more severe the shrinkage, the worse the apathy. But, apathy can begin decades before other symptoms, and be a sign of problems to come.

Malpetti, M et al. Apathy in pre-symptomatic genetic frontotemporal dementia predicts cognitive decline and is driven by structural brain changes. Alzheimer's & Dementia; 14 Dec 2020; DOI: 10.1002/alz.12252

https://medicalxpress.com/news/2020-12-apathy-onset-dementia-years-...

Reducing pesticide use with nanoparticles

Researchers  have discovered how certain silica nanoparticles could act as a traceless, degradable, and highly efficient treatment against some plant pathogens.

 With an increasing number of products banned or considered dangerous for human and animal health, the need for substitutes is acute. One approach is to stimulate plants' own immune response to pathogen attacks. Silicic acid, which naturally occurs in soil, is known to provoke such responses in plants, and amorphous silica nano-particles can release this substance in small amounts. These nanoparticles, which are also naturally present in many food crops such as cereals, are more common than most people think. They are part of food grade silica (SiO2), otherwise known as E551 on labels and packaging, and used for decades in a variety of products such as table salt, pills, or protein powders to avoid clumping.

With this in mind, the researchers aimed to create an environmentally safe nano-agrochemical for the targeted delivery of silicic acid and to stimulate plant defense. They synthesized silica nanoparticles with similar properties to those found in plants. To test their efficiency, they applied the nanoparticles on Arabidopsis thaliana (thale cress), a widely used plant model, infected with the bacterial pest Pseudomonas syringae, another model organism. The results showed that their nanoparticles can boost resistance against the bacteria in a dose-dependent manner by stimulating the plant's defense hormone, salicylic acid (which is also the active ingredient in aspirin). The researchers also investigated the interactions of the nanoparticles with plant leaves. They were able to show that nanoparticle uptake and action occurred exclusively through the leaf pores (stomata) that allow the plants to breathe.

Mohamed El-Shetehy et al. Silica nanoparticles enhance disease resistance in Arabidopsis plants, Nature Nanotechnology (2020). DOI: 10.1038/s41565-020-00812-0

https://phys.org/news/2020-12-pesticide-nanoparticles.html?utm_sour...

Shedding light on the dark side of biomass burning pollution

Oxidized organic aerosol is a major component of ambient particulate matter, substantially impacting climate, human health and ecosystems. Oxidized aerosol from biomass burning is especially toxic, known to contain a large amount of mutagens that are known carcinogens. Inhaling biomass burning particles can also cause oxidative stress and a wide range of diseases such as heart attacks, strokes and asthma. Oxidized aerosol primarily forms from the atmospheric oxidation of volatile and semi-volatile compounds emitted by sources like biomass burning, resulting in products that readily form particulate matter. Every model in use today assumes that oxidized aerosol forms in the presence of sunlight, and that it requires days of atmospheric processing to reach the levels observed in the environment. Naturally, this implies that oxidized aerosol forms in the daytime and mostly during periods with plentiful sunshine, such as in summer.

However, considerable amounts of oxidized organic aerosol forms during the winter and in other periods of low photochemical activity worldwide, often during periods of intense biomass burning. Models underestimate oxidized aerosol levels by a factor of three to five. This unresolved mystery carries significant implications for public health and climate, given that biomass burning events are often associated with population exposure to very high particulate matter levels. This issue will become more important in the future, given the increase intensity, duration and frequency of wood burning (both domestic and wildfire) around the globe.

John K. Kodros el al., "Rapid dark aging of biomass burning as an overlooked source of oxidized organic aerosol," PNAS (2020). www.pnas.org/cgi/doi/10.1073/pnas.2010365117

https://phys.org/news/2020-12-dark-side-biomass-pollution.html?utm_...

Giant Viruses Can Integrate into the Genomes of Their Hosts

Rather than introducing small chunks of DNA as other viruses do, some giant viruses can contribute more than 1 million base pairs to a host’s genome, broadening the ways in which viruses may shape eukaryote evolution.

https://www.nature.com/articles/s41586-020-2924-2.epdf?sharing_toke...

https://www.the-scientist.com/news-opinion/giant-viruses-can-integr...

Quantum insulators create multilane highways for electrons

New energy-efficient electronic devices may be possible thanks to research that demonstrates the quantum anomalous Hall (QAH) effect—where an electrical current does not lose energy as it flows along the edges of the material—over a broader range of conditions. A team of researchers from Penn State has experimentally realized the QAH effect in a multilayered insulator, essentially producing a multilane highway for the transport of electrons that could increase the speed and efficiency of information transfer without energy loss.

Tuning the Chern number in quantum anomalous Hall insulators, Nature (2020). DOI: 10.1038/s41586-020-3020-3 , www.nature.com/articles/s41586-020-3020-3

https://phys.org/news/2020-12-quantum-insulators-multilane-highways...

New type of atomic clock could help scientists detect dark matter and study gravity's effect on time

Atomic clocks are the most precise timekeepers in the world. These exquisite instruments use lasers to measure the vibrations of atoms, which oscillate at a constant frequency, like many microscopic pendulums swinging in sync. The best atomic clocks in the world keep time with such precision that, if they had been running since the beginning of the universe, they would only be off by about half a second today.

Still, they could be even more precise. If atomic clocks could more accurately measure atomic vibrations, they would be sensitive enough to detect phenomena such as dark matter and gravitational waves. With better atomic clocks, scientists could also start to answer some mind-bending questions, such as what effect gravity might have on the passage of time and whether time itself changes as the universe ages.

Now a new kind of atomic clock designed by MIT physicists may enable scientists explore such questions and possibly reveal new physics.

The researchers report in the journal Nature that they have built an atomic clock that measures not a cloud of randomly oscillating atoms, as state-of-the-art designs measure now, but instead atoms that have been quantumly entangled. The atoms are correlated in a way that is impossible according to the laws of classical physics, and that allows the scientists to measure the atoms' vibrations more accurately.

The new setup can achieve the same precision four times faster than clocks without entanglement.

Entanglement on an optical atomic-clock transition, Nature (2020). DOI: 10.1038/s41586-020-3006-1 , www.nature.com/articles/s41586-020-3006-1

https://phys.org/news/2020-12-atomic-clock-precisely.html?utm_sourc...

Where does the Earth's heat come from?

Earth generates heat. The deeper you go, the higher the temperature. At 25km down, temperatures rise as high as 750°C; at the core, it is said to be 4,000°C. Humans have been making use of hot springs as far back as antiquity, and today we use geothermal technology to heat our apartments. Volcanic eruptions, geysers and earthquakes are all signs of the Earth's internal powerhouse.

The average heat flow from the earth's surface is 87mW/m² – that is, 1/10,000th of the energy received from the sun, meaning the earth emits a total of 47 terawatts, the equivalent of several thousand nuclear power plants. The source of the earth's heat has long remained a mystery, but we now know that most of it is the result of radioactivity.

The birth of atoms

To understand where all this heat is coming from, we have to go back to the birth of the atomic elements.

The Big Bang produced matter in the form of protons, neutrons, electrons, and neutrinos. It took around 370,000 years for the first atoms to form—protons attracted electrons, producing hydrogen. Other, heavier nuclei, like deuterium and helium, formed at the same time, in a process called Big Bang nucleosynthesis.

The creation of heavy elements was far more arduous. First, stars were born and heavy nuclei formed via accretion in their fiery crucible. This process, called stellar nucleosynthesis, took billions of years. Then, when the stars died, these elements spread out across space to be captured in the form of planets.

The earth's composition is therefore highly complex. Luckily for us, and our existence, it includes all the natural elements, from the simplest atom, hydrogen, to heavy atoms such as uranium, and everything in between, carbon, iron—the entire periodic table. Inside the bowels of the earth is an entire panoply of elements, arranged within various onion-like layers.

We know little about the inside of our planet. The deepest mines reach down 10km at the most, while the earth has a radius of 6,500km. Scientific knowledge of deeper levels has been obtained through seismic measurements. Using this data, geologist divided the earth's structure into various strata, with the core at the center, solid on the inside and liquid on the outside, followed by the lower and upper mantles and, finally, the crust. The earth is made up of heavy, unstable elements and is therefore radioactive, meaning there is another way to find out about its depths and understand the source of its heat.

Radioactivity is a common and inescapable natural phenomenon. Everything on earth is radioactive—that is to say, everything spontaneously produces elementary aprticles (humans emit a few thousand per second).

There are various kinds of radioactivity, each involving the spontaneous release of particles and emitting energy that can be detected in the form of heat deposits. Here, we will be talking about "beta" decay, where an election and a neutrino are emitted. The electron is absorbed as soon as it is produced, but the neutrino has the surprising ability to penetrate a wide range of materials. The whole of the Earth is transparent to neutrinos, so detecting neutrinos generated by radioactive decay within the Earth should give us an idea of what is happening at its deepest levels.

These kinds of particles are called geonutrinos, and they provide an original way to investigate the depths of the Earth. Although detecting them is no easy matter, since neutrinos interact little with matter, some detectors are substantial enough to perform this kind of research.

https://theconversation.com/where-does-the-earths-heat-come-from-15...

A pair of lonely planet-like objects born like stars

A pair of lonely planet-like objects born like stars

An international research team led by the University of Bern has discovered an exotic binary system composed of two young planet-like objects, orbiting around each other from a very large distance. Although these objects look like giant exoplanets, they formed in the same way as stars, proving that the mechanisms driving star formation can produce rogue worlds in unusual systems deprived of a Sun.

Star-forming processes sometimes create mysterious astronomical objects called brown dwarfs, which are smaller and colder than stars, and can have masses and temperatures down to those of exoplanets in the most extreme cases. Just like stars, brown dwarfs often wander alone through space, but can also be seen in binary systems, where two brown dwarfs orbit one another and travel together in the galaxy.

Clémence Fontanive et al. A wide planetary-mass companion to a young low-mass brown dwarf in Ophiuchus, arxiv.org/abs/2011.08871 accepted for publication in The Astrophysical Journal Letters, DOI: 10.3847/2041-8213/abcaf8

https://phys.org/news/2020-12-pair-lonely-planet-like-born-stars.ht...

Scientists set a path for field trials of gene drive organisms

The modern rise of gene drive research, accelerated by CRISPR-Cas9 gene editing technology, has led to transformational waves rippling across science.

Gene drive organisms (GDOs), developed with select traits that are genetically engineered to spread through a population, have the power to dramatically alter the way society develops solutions to a range of daunting health and environmental challenges, from controlling dengue fever and malaria to protecting crops against plant pests.

But before these gene drive organisms move from the laboratory to testing in the field, scientists are proposing a course for responsible testing of this powerful technology. These issues are addressed in a new Policy Forum article on biotechnology governance, "Core commitments for field trials of gene drive organisms," published Dec. 18, 2020 in Science by more than 40 researchers.

The new commitments that address field trials are to ensure that the trials are safely implemented, transparent, publicly accountable and scientifically, politically and socially robust.

A multidisciplinary group of gene drive organism developers, ecologists and con¬servation biologists joined experts in social science, ethics and policy to outline several commitments that they deem "critical for responsible conduct of a field trial and to ensure that these technologies, if they are introduced, serve the public interest." Twelve core commitments were developed under the following broad categories: fair partnership and transparency; product efficacy and safety; regulatory evaluation and risk/benefit assessment; and monitoring and mitigation.

K.C. Long el al., "Core commitments for field trials of gene drive," Science (2020). science.sciencemag.org/cgi/doi … 1126/science.abd1908

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 "gene drive" has been used both to describe a process (the biological activity of gene drive spreading in a population) and to describe an object (the development of a "gene drive" engineering tool).

https://phys.org/news/2020-12-scientists-path-field-trials-gene.htm...

Popular European football games linked to traffic accidents in Asia

Days when high profile European football matches are played are associated with more traffic accidents in Asia than days when less popular matches are played, finds a study in the Christmas issue of The BMJ.

One explanation may be that Asian drivers stay awake until the early hours of the morning to watch high profile football games and lose sleep as a result.

Football is viewed by more people worldwide than any other sport, but most high profile games are played in Europe, so fans who live outside Europe must watch these games at odd local times owing to differences in time zones.

Asian fans are the most affected, as games scheduled to start at 8 pm in Europe means fans in Beijing, Hong Kong, and Singapore have to stay up until 4 30 am to finish the game, while fans in Seoul and Tokyo have to stay up until 5 30 am.

Given that sleep deprivation is associated with poor attention management, slower reaction times, and impaired decision making, one theory is that drivers are more likely to be involved in traffic accidents on days when high profile football games air early in the morning.

If true, this would have important policy implications, as traffic accidents can result in considerable economic and medical costs.

After taking account of potentially influential factors such as driver age, gender and experience, weather conditions, time of year, and weekend versus weekday effects, the researchers found that days when high profile football games were aired also had higher than average traffic accidents in both Singapore and Taiwan.

Association of high profile football matches in Europe with traffic accidents in Asia: archival study, BMJ (2020). DOI: 10.1136/bmj.m4465

https://medicalxpress.com/news/2020-12-popular-european-football-ga...

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Based on these figures, the researchers estimate that football games may be responsible for at least 371 accidents a year among taxi drivers in Singapore (this figure is likely to be much larger across all drivers in Singapore) and around 41,000 accidents per year among the Taiwanese general public.

In terms of annual economic losses, they estimate these to be more than €820,000 among Singapore taxi drivers and almost €14m among Taiwanese drivers and insurance companies, although they stress that these figures should be interpreted with caution.

This is an observational study, so can't establish cause, although the researchers were able to rule out many alternative explanations such as roadside conditions and driver characteristics. The researchers also point to some limitations, such as a lack of data on the severity of the accidents reported and being unable to compare match days against non-game days.

Nevertheless, they suggest that football's governing bodies could consider scheduling high profile games on Friday or Saturday evenings local European time (Saturday or Sunday early mornings local Asian time) when fans can sleep in immediately after watching games.

The most consumed species of mussels contain microplastics all arou...

"If you eat mussels, you eat microplastics." 

A research team investigated the microplastic load of four mussel species which are particularly often sold as food in supermarkets from twelve countries around the world. The scientists now present their research results in the journal Environmental Pollution.

All the samples analyzed contained microplastic particles, and the researchers detected a total of nine different types of plastic. Polypropylene (PP) and polyethylene terephthalate (PET) were the most common types of plastic. Both are plastics ubiquitous to people's everyday lives all over the world. To make the analyses of different sized mussels comparable, one gram of mussel meat was used as a fixed reference. According to the study, one gram of mussel meat contained between 0.13 and 2.45 microplastic particles. Mussel samples from the North Atlantic and South Pacific were the most contaminated. Because mussels filter out microplastic particles from the water in addition to food particles, a microplastic investigation of the mussels allows indirect conclusions to be drawn about pollution in their respective areas of origin.

The microplastic particles detected in the mussels were of a size of between three and 5,000 micrometers, i.e. between 0.003 and five millimeters.

B.N. Vinay Kumar et al. Analysis of microplastics of a broad size range in commercially important mussels by combining FTIR and Raman spectroscopy approaches, Environmental Pollution (2020). DOI: 10.1016/j.envpol.2020.116147

https://phys.org/news/2020-12-consumed-species-mussels-microplastic...

Scientist tests new technology for removing, destroying 'forever ch...

University of Rhode Island hydrogeologist Thomas Boving and colleagues at EnChem Engineering Inc. are testing a proprietary new technology for quickly removing and destroying hazardous chemical compounds from soil and groundwater. If proven effective, the technology could soon be applied to cleaning up the abundant per- and polyfluoroalkyl substances, collectively referred to as PFAS and 'forever chemicals,' that contaminate drinking water supplies.

PFAS compounds have been in use for more than 60 years and are found in common household goods like non-stick cookware, stain-proof carpets and pizza boxes, as well as in firefighting foams and other industrial products. Because they do not break down easily in the environment, they find their way into human and animal tissues and can lead to many serious diseases.

First, they flushed the compounds out of the ground by pumping in a sugar molecule that has the ability to remove PFAS from the soil and groundwater. Then they pumped the solution out of the ground and hit it with a chemical oxidation process to destroy the compounds.

https://phys.org/news/2020-12-scientist-technology-chemicals.html?u...

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Being Scientists Doesn’t Make Us Science Communicators

Effectively relating science to the public is a science in itself, and expertise on a topic doesn’t guarantee expertise in explaining it.

https://www.the-scientist.com/news-opinion/opinion-being-scientists...

Why are our tears salty?

Well, all fluids in our bodies have a little bit of salt in them. This salt is made into electricity to help our muscles contract and our brains to think. The amount of salt in our body fluids (like tears, sweat, and saliva) is about the same as the amount of salt in our blood — just under 1%, or about two teaspoons of salt per litre.

The saltiness of your tears can actually vary depending on what kind of tears your eyes are making.

That’s right, your eyes — or a part of your eyes called the lacrimal gland, to be precise — make three different types of tears. These are called basal tears, reflex tears and emotional tears.

• basal tears keep your eyes wet and stop nasty germs infecting your eyes
• reflex tears are made when your eyes need to wash away something harmful that gets in, such as smoke or a grain of sand
• emotional tears are the kind you cry when you’re feeling very happy or sad.

Basal tears and reflex tears have more salt in them than emotional tears, which is important for keeping your eyes healthy. Emotional tears contain more of other things, including a hormone (a special type of chemical in your body) that works like a natural painkiller. This might help to explain why we sometimes feel better after having a good cry.

https://theconversation.com/curious-kids-why-are-our-tears-salty-15...

These ‘beetlebots’ keep flying, even after crashing into poles