Sci&Tech

Humans Have Changed The Course of Evolution in Ways We Never Predicted, Scientist Warns

noreply@blogger.com (Anonymous) — Wed, 14 Nov 2018 16:10:00 +0500

By now, most of us can list a variety of ways our species is making a mess of this planet.

Canadian zoologist Sarah Otto reports in detail how humans have made a mess of things, with the aim of asking how it affects evolution overall. The answer isn't academic, either – it could show us just how bad things really are.

"The speed with which the biotic and abiotic environment of species has changed has already altered the evolutionary trajectory of species, a trend that promises to escalate," Otto says in her recent article.

A change in course for ecosystems is nothing new. Around 90 percent of all species that have lived on Earth have gone the way of the dodo, making extinction an inevitable feature of the biosphere.

But the forces that have seen the rise and fall of species in times gone by tend to be rather slow compared to what's been happening over the past century or so.

A hundred years ago, we humans numbered roughly 1.8 billion. Now our population is closer to 7.6 billion, having grown on average around 1 percent every year. If having more mouths to feed isn't bad enough, individual imprints on the landscape have grown by half a percent per year.

Having more people with a greater effect on the environment has led to an exponential growth in devastation, driving up the global extinction rate and seeing an end to a significant number of species in the space of a single human lifetime.

On average, we've stripped 8 percent of the carbon from the top 2 metres (6 feet) of topsoil, raised the temperature of the atmosphere by nearly 1 degree Celsius (1.8 degrees Fahrenheit), and lowered the pH of the oceans by about 0.1 units.

This impact isn't just monumental in scale. It's unprecedented in speed. Meaning we have little to tell us how biology responds to this new spin on 'natural' selection.

"Beyond the numbers, the world's biological diversity is changing, through evolutionary change at both the within and between species levels," says Otto.

The pressures affecting this shift in biodiversity can be categorised in various ways. Otto puts aside intentional selection pressures – those we deliberately enact by cross-breeding new varieties or genetic engineering – and focuses on those we affect incidentally.

For example, simply by physically modifying the landscape with new structures, we influence how animals move, plants grow, and how microbes proliferate.

This can have a drastic effect on whether a species survives or vanishes, or subtly influence its functions and morphology.

"The wing span of cliff swallows has evolved to be shorter near roads, with roadkilled swallows having longer wings, consistent with selection for increased manoeuverability in the face of traffic," says Otto.

We've also modified the living environment, rapidly transplanting species through boundaries that once would have impeded their spread.

And then there is the obvious pressure imposed by our predatory and gathering demands, hunting animals of the right size or culling weeds or pests that might affect our crop yields.

There's no shortage of examples of lost species and remarkable adaptations to human presence. But the rate at which new species appear is still a bit of a mystery.

"Less is known about how humans have altered the rate of speciation," says Otto.

There are plenty of estimates, with some of the less optimistic suggesting it could take millions of years for some aspects of biodiversity to spring back to pre-modern vigour.

As destructive as we are, we humans have also contributed a reasonable amount to increasing genetic diversity in some ways, whether through splitting populations apart or carving out niches in new environments.

This all adds up to a question of balance in biodiversity over a long timescale. Is some kind of large scale equilibrium achievable in this new evolutionary landscape? Or human pressures setting us up for an inevitable slide into ever increasing hardship?

We simply don't know. And Otto thinks that's a problem.

"As we have witnessed with the evolution of antibiotic resistance, humans may impose selection, but we will often not retain the upper hand," she warns.

When it comes to the environment, the news isn't always pleasant. But the fact we still know so little about our impact is something we should really be concerned about.

We Thought Earth's Water Came From Comets. Turns Out That's Not The Full Story

noreply@blogger.com (Anonymous) — Wed, 14 Nov 2018 16:06:00 +0500

We have comets and asteroids to thank for Earth's water, according to the most widely-held theory among scientists. But it's not that cut-and-dried. It's still a bit of a mystery, and a new study suggests that not all of Earth's water was delivered to our planet that way.

Hydrogen is the most abundant element in the Universe, and it's at the center of the question surrounding Earth's water.

This new study was co-led by Peter Buseck, Regents' Professor in the School of Earth and Space Exploration and School of Molecular Sciences at Arizona State University.

In it, the authors suggest that the hydrogen came, at least partially, from the solar nebula, a cloud of gas and dust left over after the Sun formed.

Before we dig in to the details in this new study, it's helpful to look at the long-held theory that it may replace.

Earth's Water: The Widely-Held Theory

For a long time, most scientists believed the water-from-comets-and-asteroids version of water's origin here on Earth. It all starts with the formation of the Sun.

When the Sun formed out of a molecular cloud, it swept up most of the material in the cloud, leaving a little left over for everything else: planets, asteroids, and comets.

Once the Sun burst into life with fusion, a powerful solar wind sent a lot of hydrogen from its outer layers out beyond where the inner rocky planets - Mercury, Venus, Earth, and Mars - are today.

This is the realm of the gas giants, and more importantly, comets and asteroids.

Comets are icy, rocky bodies, thought to contain significant amounts of the hydrogen blown out there by the early Sun, and asteroids too, although to a lesser extent. They became a significant reservoir for hydrogen.

When Earth formed, it was a molten ball, its surface kept in that state by repeated collision with asteroids. So far, so good, since the early Solar System was a much more chaotic place than it is now.

As asteroids and comets struck this hot Earth, the water and the hydrogen in it were boiled off into space. As Earth cooled over time, water from comet and asteroid collisions was allowed to condense on Earth, and not be boiled off into space. The water stuck around.

The evidence for this lies in isotope ratios. The ratio of the heavy hydrogen isotope deuterium to normal hydrogen is a chemical signature.

Two bodies of water with the same ratio must have the same origin, the thinking goes. And Earth's oceans have the same ratio as water on asteroids. That's a very simplified version of the widely-held theory of how water got to Earth.

Earth's Water: A Leaky Theory With Holes In It

But scientists are malcontents, always trying to have a better, more thorough understanding of things. They were questioning the "water from comets" theory before this newest study came out.

Back in 2014, some scientists studied the issue by looking at meteorites of different ages. (Meteorites are just asteroids that have struck Earth.) First they looked at what are known as 'carbonaceous chondrite meteorites'.

They're the oldest ones we know of, and they formed about the same time as the Sun did. They're the primary building blocks of Earth.

Next, they studied meteorites that we think originated from the large asteroid Vesta. Vesta formed in the same region as Earth, about 14 million years after the solar system was born.

According to this 2014 study, the ancient meteorites resembled the bulk Solar System composition and have a lot of water in them, so they've been widely considered to be the source of Earth's water.

The measurements in this 2014 study showed that these meteorites have the same chemistry as the carbonaceous chondrites and rocks found on Earth. They concluded that carbonaceous chondrites are the most likely common source of water.

At the time, Horst Marschall, one of the authors of the study, said, "The study shows that Earth's water most likely accreted at the same time as the rock. The planet formed as a wet planet with water on the surface."

The team behind that study acknowledged that some of our water did come from impacts.

Which brings us to this new study, which reinforces the conclusions from the 2014 study.

Earth's Water: All About The Hydrogen

The authors of this new study say that the oceans and their isotope ratios may not tell the whole story. "It's a bit of a blind spot in the community," said Steven Desch, a professor of astrophysics in the School of Earth and Space Exploration at Arizona State University in Tempe, Arizona.

"When people measure the [deuterium-to-hydrogen] ratio in ocean water and they see that it is pretty close to what we see in asteroids, it was always easy to believe it all came from asteroids." It's hard to blame them; it's a pretty compelling piece of evidence.

Desch and the other authors of this new study point to research published in 2015 showing that Earth's oceans may not be representative of Earth's primordial water.

The oceans may have cycled between the surface and a deeper reservoir of water, deep in the Earth. This may have changed the ratio over time, and it may mean that this deeper water represents at least some of Earth's true primordial water.

And that water may have come directly from the solar nebula, rather than through comet and asteroid impacts.

The study develops a new theoretical model of Earth's formation to explain these differences between hydrogen in Earth's oceans and at the core-mantle boundary.

This new model shows large water-logged asteroids formed into planets billions of years ago in the solar nebula swirling around the Sun. These planetary embryos suffered sequential collision and they grew quickly.

Eventually, they say, a powerful enough collision melted the surface of the largest embryo into an ocean of magma. This largest embryo became Earth.

This large embryo had enough gravity to hold onto an atmosphere, and it attracted gases, including hydrogen, the most abundant one, from the solar nebula to form one.

The hydrogen in the solar nebula contained less deuterium and is lighter than asteroidal hydrogen. It dissolved into the molten iron of the magma ocean on Earth.

The hydrogen was pulled to the center of Earth by a process called isotopic fractionation. Hydrogen is attracted to iron and was delivered the Earth's core by the iron.

Deuterium, the heavy hydrogen isotope, remained in the magma, which cooled to form the Earth's mantle. Continuing impacts brought more water and mass to Earth, until it reached the mass it is today.

The key point in this new model is that hydrogen in the Earth's core is different than hydrogen in the mantle and in the oceans. Core water has much less deuterium. But what does it all mean?

The new model allowed the authors to estimate the amounts of water that came from asteroid impacts as Earth grew and evolved, compared to how much came from the solar nebula when Earth formed.

Their conclusion?

"For every 100 molecules of Earth's water, there are one or two coming from solar nebula," said Jun Wu, assistant research professor in the School of Molecular Sciences and School of Earth and Space Exploration at Arizona State University and co-lead author of the study.

Conclusion: It's About More Than Just Earth's Water

This study is a new perspective on planetary formation, development, and on how early life could flourish on a young planet.

"This model suggests that the inevitable formation of water would likely occur on any sufficiently large rocky exoplanets in extrasolar systems. I think this is very exciting." – Jun Wu, School of Molecular Sciences and School of Earth and Space Exploration at ASU, co-lead author.

Previously, we thought that the only planets that could have life on them would have to be in a solar system rich with water-bearing asteroids and comets. But that may not be the case. In other solar systems, not all Earth-like planets have access to asteroids loaded with water.

The new study suggests any habitable exoplanets might have gotten water from the solar nebula in their system. Earth hides most of its water in its interior. Earth has roughly two ocean in its mantle, and 4 or 5 in its core. Exoplanets may be similar.

"This model suggests that the inevitable formation of water would likely occur on any sufficiently large rocky exoplanets in extrasolar systems," Wu said. "I think this is very exciting."

There's one cautionary point in this new model though, and that involves the hydrogen fractionation.

It's not well-understood how the deuterium-to-hydrogen ratio changes when the element dissolves in iron, which is at the center of this new model. It had to be estimated in this new study.

Overall, the new study fits in well with other research into Earth's water. Once more work is done on hydrogen fractionation, the new model can be tested more rigorously.

Scientists Found a Bird That's 3 Species in One, And We've Never Seen Anything Like It

noreply@blogger.com (Anonymous) — Wed, 14 Nov 2018 00:33:00 +0500

An unusual warbler in Pennsylvania has been discovered harbouring an incredible genetic secret. He's the hybrid of not two, but three different species of bird. His mother was a hybrid of two warblers - and his father was a warbler of an entirely different third genus.

"It's extremely rare," said ornithologist David Toews of Cornell Lab of Ornithology.

"The female is a Golden-winged/Blue-winged warbler hybrid - also called a Brewster's warbler. She then mated with a Chestnut-sided warbler and successfully reproduced."

Bird hybrids aren't uncommon - after all, Brewster's warbler has been known since 1874, and it's well known that hybridisation can lead to the development of new species.

But generally, it's only two species. The fact that this one bird is a three-species hybrid is fascinating - but it also reveals something alarming about declining warbler numbers in Appalachia.

(Cornell Lab of Ornithology)

He was first spotted in May 2018, by bird-watcher Lowell Burket. After taking a video of the little fellow, Burkett noticed that he had colouration similar to both Golden-winged (Vermivora chrysoptera) and Blue-winged (Vermivora cyanoptera) warblers - but that his song was more like that of a Chestnut-sided warbler (Setophaga pensylvanica).

After spotting the strange bird several times, Burket reported his discovery on The Cornell Lab of Ornithology's birding website, eBird, and reached out to researchers.

"I tried to make the email sound somewhat intellectual so they wouldn't think I was a crackpot," Burket said.

"Within a week researcher David Toews came down. We found the bird again and collected a blood sample and measurements. It was a very interesting and exciting morning for us."

A few days later Burket got a text message from Towes, punctuated with several exclamation marks - it turned out the amateur bird-watcher had been correct in his observations.

The researchers studied the genes that code for colouration, and used those to piece together what the mother bird would have looked like - arriving at a Brewster's warbler mum and a Chestnut-sided warbler dad.

It's the first time this hybrid combination has ever been seen. But it's also sobering. Some populations of Golden-winged warblers have declined dramatically across Appalachia.

A new type of hybridisation event could indicate that there are not enough mates for everyone, so the birds are having to look to other species for reproductive options.

(Lowell Burket)

"That this hybridisation occurred within a population of Golden-winged warblers in significant decline suggests that females may be making the best of a bad situation," Toews said.

"It also tells us that wood-warblers in general have remained genetically compatible long after they evolved major differences in appearance."

We know that some bird hybrids remain fertile, and are able to reproduce - after all, the triple-hybrid's mum was a hybrid herself. At this time, though, it's not known whether the triple hybrid will be able to reproduce - or, even if he can, whether he looks too weird for female birds to choose him as a mate.

It's definitely a situation that bears watching, though - not just for the individual bird, and the warblers of Appalachia, but for what it can tell us about avian hybridisation in general.

"This finding of 'hybrids hybridising' provides a novel avenue for the movement of genes between distantly related taxa not yet observed or described in birds," the researchers wrote in their paper

Primates of the Caribbean: Ancient DNA reveals history of mystery monkey

noreply@blogger.com (Anonymous) — Wed, 14 Nov 2018 00:22:00 +0500

Weird evolution revealed in now-extinct monkey which inhabited Jamaica until a few hundred years ago

Analysis of ancient DNA of a mysterious extinct monkey named Xenothrix -- which displays bizarre body characteristics very different to any living monkey -- has revealed that it was in fact most closely related to South America's titi monkeys (Callicebinae). Having made their way overwater to Jamaica, probably on floating vegetation, their bones reveal they subsequently underwent remarkable evolutionary change.

Xenothrix's close relative, the red titi monkey (Callicebus cupreus).

Analysis of ancient DNA of a mysterious extinct monkey named Xenothrix -- which displays bizarre body characteristics very different to any living monkey -- has revealed that it was in fact most closely related to South America's titi monkeys (Callicebinae). Having made their way overwater to Jamaica, probably on floating vegetation, their bones reveal they subsequently underwent remarkable evolutionary change.

The research published today in Proceedings of the National Academy of Sciences (12 November 2018) and carried out by a team of experts from international conservation charity ZSL (Zoological Society of London), London's Natural History Museum (NHM), and the American Museum of Natural History in New York, also reveals that monkeys must have colonised the Caribbean islands more than once. The study reports an incredible discovery of how the unusual ecology of islands can dramatically influence animal evolution.

Xenothrix, unlike any other monkey in the world, was a slow-moving tree-dweller with relatively few teeth, and leg bones somewhat like a rodent's. Its unusual appearance has made it difficult for scientists to work out what it was related to and how it evolved. However, the scientific team have successfully extracted the first ever ancient DNA from an extinct Caribbean primate -- uncovered from bones excavated in a Jamaican cave and providing important new evolutionary insights.

Professor Samuel Turvey from ZSL, a co-author on the paper, said: "This new understanding of the evolutionary history of Xenothrix shows that evolution can take unexpected paths when animals colonise islands and are exposed to new environments. However, the extinction of Xenothrix, which evolved on an island without any native mammal predators, highlights the great vulnerability of unique island biodiversity in the face of human impacts."

Professor Ian Barnes, whom runs the NHM's ancient DNA lab, and co-author said: "Recovering DNA from the bones of extinct animals has become increasingly commonplace in the last few years. However, it's still difficult with tropical specimens, where the temperature and humidity destroy DNA very quickly. I'm delighted that we've been able to extract DNA from these samples and resolve the complex history of the primates of the Caribbean."

It is likely that Xenothrix's ancestors colonised Jamaica from South America around 11 million years ago, probably after being stranded on natural rafts of vegetation that were washed out of the mouths of large South American rivers. Many other animals, such as large rodents called hutias (Capromyidae) that still survive on some Caribbean islands today, probably colonised the region in the same way.

Ross MacPhee of the American Museum of Natural History's Mammalogy Department, a co-author of the study, said: "Ancient DNA indicates that the Jamaican monkey is really just a titi monkey with some unusual morphological features, not a wholly distinct branch of New World monkey. Evolution can act in unexpected ways in island environments, producing miniature elephants, gigantic birds, and sloth-like primates. Such examples put a very different spin on the old cliché that 'anatomy is destiny.'"

What Xenothrix may have looked like has been greatly debated, with suggestions that it looked like a kinkajou (Potos) or a night monkey (Aotus). Living titi monkeys are small tree-dwelling monkeys found across tropical South America, with long soft red, brown, grey or black fur. They are active during the day, extremely territorial and vocal, and live up to 12 years in the wild, with the father often caring for the young.

Though the Galapagos Islands are famous for inspiring Charles Darwin's theory of evolution, the islands of the Caribbean have also been home to some of the most unusual and mysterious species to have ever evolved. However, the Caribbean has also experienced the world's highest rate of mammal extinction since the end of the last ice age glaciation, likely caused by hunting and habitat loss by humans, and predation by invasive mammals brought by early settlers.

Transforming carbon dioxide into industrial fuel

noreply@blogger.com (Anonymous) — Wed, 14 Nov 2018 00:11:00 +0500

One day in the not-too-distant future, the gases coming from power plants and heavy industry, rather than spewing into the atmosphere, could be captured and chemically transformed from greenhouse gases like carbon dioxide into industrial fuels or chemicals thanks to a new system that can use renewable electricity to reduce carbon dioxide into carbon monoxide -- a key commodity used in a number of industrial processes.
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FULL STORY

"To explore more possibilities, my group has also developed several copper-based catalysts that can further reduce CO2 into products that are much more valuable," said Haotian Wang.

Imagine a day when -- rather than being spewed into the atmosphere -- the gases coming from power plants and heavy industry are instead captured and fed into catalytic reactors that chemically transform greenhouse gases like carbon dioxide into industrial fuels or chemicals and that emit only oxygen.

It's a future that Haotian Wang says may be closer than many realize.

A Fellow at the Rowland Institute at Harvard, Wang and colleagues have developed an improved system to use renewable electricity to reduce carbon dioxide into carbon monoxide -- a key commodity used in a number of industrial processes. The system is described in a November 8 paper published in Joule, a newly launched sister journal of Cell press.

"The most promising idea may be to connect these devices with coal-fired power plants or other industry that produces a lot of CO2," Wang said. "About 20 percent of those gases are CO2, so if you can pump them into this cell...and combine it with clean electricity, then we can potentially produce useful chemicals out of these wastes in a sustainable way, and even close part of that CO2 cycle."

The new system, Wang said, represents a dramatic step forward from the one he and colleagues first described in a 2017 paper in Chem.

Where that old system was barely the size of a cell phone and relied on two electrolyte-filled chambers, each of which held an electrode, the new system is cheaper and relies on high concentrations of CO2 gas and water vapor to operate more efficiently -- just one 10-by-10-centimeter cell, Wang said, can produce as much as four liters of CO per hour.

The new system, Wang said, addresses the two main challenges -- cost and scalability -- that were seen as limiting the initial approach.

"In that earlier work, we had discovered the single nickel-atom catalysts which are very selective for reducing CO2 to CO...but one of the challenges we faced was that the materials were expensive to synthesize," Wang said. "The support we were using to anchor single nickel atoms was based on graphene, which made it very difficult to scale up if you wanted to produce it at gram or even kilogram scale for practical use in the future."

To address that problem, he said, his team turned to a commercial product that's thousands of times cheaper than graphene as an alternative support -- carbon black.

Using a process similar to electrostatic attraction, Wang and colleagues are able to absorb single nickel atoms (positively charged) into defects (negatively charged) in carbon black nanoparticles, with the resulting material being both low-cost and highly selective for CO2 reduction.

"Right now, the best we can produce is grams, but previously we could only produce milligrams per batch," Wang said. "But this is only limited by the synthesis equipment we have; if you had a larger tank, you could make kilograms or even tons of this catalyst."

The other challenge Wang and colleagues had to overcome was tied to the fact that the original system only worked in a liquid solution.

The initial system worked by using an electrode in one chamber to split water molecules into oxygen and protons. As the oxygen bubbled away, protons conducted through the liquid solution would move into the second chamber, where -- with the help of the nickel catalyst -- they would bind with CO2 and break the molecule apart, leaving CO and water. That water could then be fed back into the first chamber, where it would again be split, and the process would start again.

"The problem was that, the CO2 we can reduce in that system are only those dissolved in water; most of the molecules surrounding the catalyst were water," he said. "There was only a trace amount of CO2, so it was pretty inefficient."

While it may be tempting to simply increase the voltage applied on the catalyst to increase the reaction rate, that can have the unintended consequence of splitting water, not reducing CO2, Wang said.

"If you deplete the CO2 that's close to the electrode, other molecules have to diffuse to the electrode, and that takes time," Wang said. "But if you're increasing the voltage, it's more likely that the surrounding water will take that opportunity to react and split into hydrogen and oxygen."

The solution proved to be relatively simple -- to avoid splitting water, the team took the catalyst out of solution.

"We replaced that liquid water with water vapor, and feed in high-concentration CO2 gas," he said. "So if the old system was more than 99 percent water and less than 1 percent CO2, now we can completely reverse that, and pump 97 percent CO2 gas and only 3 percent water vapor into this system. Before those liquid water also functions as ion conductors in the system, and now we use ion exchange membranes instead to help ions move around without liquid water.

"The impact is that we can deliver an order of magnitude higher current density," he continued. "Previously, we were operating at about ten milliamps-per-centimeter squared, but today we can easily ramp up to 100 milliamps."

Going forward, Wang said, the system still has challenges to overcome -- particularly related to stability.

"If you want to use this to make an economic or environmental impact, it needs to have a continuous operations of thousands of hours," he said. "Right now, we can do this for tens of hours, so there's still a big gap, but I believe those problems can be addressed with more detailed analysis of both the CO2 reduction catalyst and the water oxidation catalyst."

Ultimately, Wang said, the day may come when industry will be able to capture the CO2 that is now released into the atmosphere and transform it into useful products.

"Carbon monoxide is not a particularly high value chemical product," Wang said. "To explore more possibilities, my group has also developed several copper-based catalysts that can further reduce CO2 into products that are much more valuable."

Wang credited the freedom he enjoyed at the Rowland Institute for helping lead to breakthroughs like the new system.

"Rowland has provided me, as an early career researcher, a great platform for independent research, which initiates a large portion of the research directions my group will continue to push forward," said Wang, who recently accepted a position at Rice University. "I will definitely miss my days here."

This Insane Device Both Harvests Solar Energy And Sends Excess Heat Into Space

noreply@blogger.com (Anonymous) — Wed, 14 Nov 2018 00:04:00 +0500

We're facing a deadly Catch 22. As the world grows hotter, people crank up the air con. As they crank the air con, the world grows hotter. And so on. And so on.

If it seems like there's no escape from this gloomy, no-win situation, take heart: a new technology developed by scientists from the US and China could literally shine a light in the dark – and not just any dark either, but the cold emptiness of seemingly endless space.

Researchers at Stanford University have invented a new kind of solar panel technology that not only harvests light from the Sun and converts it into electricity (as conventional panels do), but can also beam excess heat into space at the same time.

"We've built the first device that one day could make energy and save energy, in the same place and at the same time, by controlling two very different properties of light," explains electrical engineer and senior author of the new research, Shanhui Fan.

(L.A. Cicero)

The principle Fan is talking about is called radiative cooling, in which an object – any object, including buildings, or even your own body – emits heat in the form of infrared light.

When objects do this, they simultaneously lose heat by the process of thermal radiation, but while the phenomenon might seem like a great way of displacing Earth's impending heat problems, there's a catch: not all the emitted heat escapes our atmosphere and makes it into space.

"Think about the atmosphere as a big blanket around the Earth," one of the researchers, Zhen Chen, formerly of Stanford and now a professor at the Southeast University of China, told Fast Company.

"This blanket does not allow heat easily to go from the Earth to the cold universe. But there are 'holes' in the blanket, if you want to think about it that way, through which the heat can radiate out to outer space."

The new prototype the researchers developed is a first-of-its-kind attempt at combining a radiative cooling device with a conventional solar panel, creating a type of hybrid technology that both absorbs sunlight while emitting infrared light into the sky.

The unit is composed of a conventional solar absorber array about the size of a compact disc (if you remember those), which sits above a similar circle-shaped radiative cooler, made from silicon nitride, silicon, and aluminium layers enclosed in a vacuum.

The idea is that the solar panel is transparent for infrared, so while it should absorb most of the Sun's light, infrared light (with a wavelength between 8 and 13 micrometres) passes through it and can be emitted into space – to the extent it can navigate atmospheric 'holes' at least.

In testing, the device – which builds on the team's earlier radiative cooling innovations in 2014 and 2015 – succeeded as a proof of concept, with the bottom layer (the radiative cooler) recording lower temperatures than both the ambient air temperature and the solar panel.

(Chen et al/Joule)

"This shows that heat radiated up from the bottom, through the top layer and into space," Chen explains in a statement, although there's a lot more work to be done before this kind of double-duty solar panel could be installed on rooftops around the world.

For starters, the solar panel in the team's prototype wasn't actually functional in terms of producing electricity, which is the next problem for the researchers to solve: developing working solar cells with elements that don't block infrared light from boldly going where no one has gone before.

Once that technical hurdle is overcome, the sky is no longer the limit.

"It is widely recognised that the Sun is a perfect heat source nature offers human beings on Earth," says Chen.

"It is less widely recognised that nature also offers human beings outer space as a perfect heat sink."

This Jupiter Cloud Kinda Looks Like a Dolphin, So We Found Some More Animals to Keep It Company

noreply@blogger.com (Anonymous) — Tue, 13 Nov 2018 23:58:00 +0500

Humans have a hard-wired habit of seeing patterns, shapes, and faces in all kinds of objects. For some these phenomena are conspiracy fuel, but it's really just our brains trying to make sense of the world.

Case in point, the Mars Warrior Women, the Mars Face, or any half decent optical illusion.

This time, however, we've gone a little further afield. Move over Earth and Mars, some news sites have reported that NASA's Juno spacecraft has spotted a dolphin swimming on Jupiter!

Of course, there are no actual dolphins in Jupiter's -145 degrees Celsius (-229 degrees Fahrenheit) chilly clouds.

But the picture, taken by Juno and highlighted on Twitter by artist Seán Doranis pretty cool, and the shape he pointed out does look surprisingly like a dolphin:

Twitter Ads information and privacCan you see the cloud dolphin? If not, no worries - we've highlighted it for you in all its glory.

(NASA/SwRI/MSSS/Brian Swift/Seán Doran; ScienceAlert)

Don't let its docile demeanour fool you – according to Doran, this cloud beast is probably at least the size of Earth.

Juno has been travelling in Jupiter's orbit and taking incredible images since mid-2016, and each cache of photos is edited by a team of citizen scientists.

On each flyby, JunoCam can take between 12 and 20 images, and Juno just finished its 16th flyby - so there are lots of breathtaking images to chose from.

And since there's so many photos, and just one lonely dolphin, here at ScienceAlert we decided to see what other animals we might find on the swirling surface of the gas giant.

So, please enjoy this extremely unofficial list of the animals of Jupiter.

The parrot:

(NASA/JPL-Caltech/SwRI/MSSS/Gerald Eichstädt/Seán Doran; ScienceAlert)

The octopus (or cuttlefish?):

(NASA/JPL-Caltech/SwRI/MSSS/Gerald Eichstäd/Seán Doran; ScienceAlert)

The seahorse:

(NASA/JPL-Caltech/SwRI/MSSS/Jason Major; ScienceAlert)

The snail:

(NASA/JPL-Caltech/SwRI/MSSS/Gerald Eichstädt/Seán Doran; ScienceAlert)

Both the snail and the parrot are from Juno's most recent flyby on the 29th of October, while the octopus was from the 13th flyby back in May.

The seahorse was taken in mid-July, while the spacecraft performed its 14th flyby of Jupiter. Juno was about 6,200 kilometers (3,900 miles) from the tops of Jupiter's clouds when it took the seahorse photo above.

Oh, and here's another dolphin:

(NASA/JPL-Caltech/SwRI/MSSS/Gerald Eichstädt/Seán Doran; ScienceAlert)

Obviously these are all in jest, but it really does go to show that humans love seeing patterns in unusual places.

We're sure there are plenty more animals left to discover - if you find any, we'd love if you sent us the picture! Maybe we'll start a Jovian zoo.

An Incredibly Fast 'Dark Matter Hurricane' Is Blowing Past Earth Right Now

noreply@blogger.com (Anonymous) — Tue, 13 Nov 2018 23:46:00 +0500

If astronomers' calculations are correct, the Solar System is right in the middle of a turbulent space event: a vast 'hurricane' of dark matter, blowing at an insane speed of 500 kilometres per second (310 mps).

We can't see it, and we can't feel it - but it could mean that a direct detection of dark matter is closer than we thought.

Dark matter is one of the big conundrums of the Universe. We have never directly detected it, and we don't know exactly what it even is - but we do know that it's out there. We can infer it based on the motions of the stars and galaxies, which are far too fast for the amount of observable mass.

So there's something else out there, some other mass creating the gravity to influence those cosmic movements. We can even, based on those movements, calculate that invisible mass. "Dark matter" - whatever that might be - is the name we give that mass, and scientists are working on ways to detect it directly.

But we're not there yet. So how do physicists know we're in the middle of a tremendous storm of dark matter? The clue lies in the motion of the stars.

With the release of data from the Gaia satellite last year, astronomers discovered a stellar stream, the dissolving remains left behind by a large dwarf spheroidal galaxy that was eaten by the Milky Way many years ago.

There have been several such streams of stars detected in the Milky Way, but S1, as it is now known, is unusual in that the neighbourhood of the Solar System is smack-bang right in its path of 30,000 stars.

None of them are going to hit us - so you can relax about any fears you might have harboured of fiery stellar death - but it does mean that the dark matter associated with this last shred of the cannibalised dwarf galaxy is moving along with the stream.

Theoretical physicist Ciaran O'Hare from the University of Zaragoza in Spain has led a team of researchers in figuring out the effect of S1 on the dark matter in our little corner of the galaxy.

They looked at different models for the density and distribution of the dark matter flowing in on the S1 stream, and then predicted the dark matter signatures for these models that could be picked up by our detectors here on Earth.

One of these potential signatures is produced by the hypothetical weakly interacting massive particles, known as WIMPs. If these particles exist, we should be able to detect them via their collisions with electrons or atomic nuclei, which would cause charged particles on Earth to recoil, producing light that could be picked up by liquid xenon or crystal detectors.

Based on their calculations, the team determined that these WIMP detectors are unlikely to see any effect from S1, although it's possible that future tech, as it becomes more refined and advanced, could.

Axion detectors - such as the Axion Dark Matter Experiment - have a better chance, they determined. Axions are, again, only hypothetical at this point. If they exist, they are incredibly light, around 500 million times lighter than an electron, and it's possible they are a principal component of cold dark matter.

According to calculations by theoretical physicist Pierre Sikivie, these ultralight particles - which we can't see - could be converted to photons which we cansee, in the presence of a strong magnetic field.

"Axion haloscopes possess by far the greatest potential sensitivity to the S1 stream if its dark matter component is sufficiently cold," the researchers wrote in their paper. "Once the axion mass has been discovered, the distinctive velocity distribution of S1 can easily be extracted from the axion power spectrum."

The Axion Dark Matter Experiment, as far as we know, hasn't made an S1 detection either. But knowing what to look for could help scientists improve the chances of this - and if no detection is made, improve detection technology for the ongoing search for dark matter in the future.

Our Brains Could Actually Have Bacteria Living Inside, New Evidence Suggests

noreply@blogger.com (Anonymous) — Tue, 13 Nov 2018 23:40:00 +0500

The microbes that inhabit the human gut are thought to be responsible for many things, affecting our health, our genes, and even our emotions.

Scientists are continually making new discoveries about the scale and influence of the human microbiome, but the latest evidence is particularly startling: this thriving bacterial kingdom might not be alone, but could be linked to a separate "human brain microbiome" that resides in your head.

The findings, which are only preliminary at this stage, were recently presented at a poster session at the Neuroscience 2018 annual meeting by researchers from the the University of Alabama in Birmingham.

It's worth mentioning that up front, because these types of scientific presentations are often geared towards sharing results from new or ongoing research that may not have been peer-reviewed by other scientists yet - which is the case here.

The reason that's important is because so far we're still learning how gut microbiota can influence brain function and behaviour, and the new suggestion – that the human brain has its own microbiome population – could be a landmark finding if it can be confirmed in future study.

"This is the hit of the week," neuroscientist Ronald McGregor from the University of California, Los Angeles, who was not involved in the research, told Science.

"It's like a whole new molecular factory [in the brain] with its own needs. … This is mind-blowing."

In the new research, a team led by neuroanatomist Rosalinda Roberts examined brain samples taken from 34 deceased people – about half of whom had schizophrenia, with the other half being considered healthy before they died.

"We did serial section analysis for identification and quantification," the researchers explain in their abstract.

"All cases contained bacteria in varying amounts. Bacteria were rod shaped, and contained a capsule, nucleoid, ribosomes and vacuoles."

The researchers say the density of the bacteria varied according to where it was found in the brain region, with abundant microbes in the substantia nigra, hippocampus, and prefrontal cortex.

They were also found in cells called astrocytes that are increasingly being discovered to play an important role in how neurons communicate.

As for how the bacteria got there, the researchers don't know, but Roberts speculates they could have been transported by blood vessels, finding a home in axons and at the blood brain barrier.

While the team acknowledges it's possible the microbes found their way into the brain tissue by some process of surgical contamination during postmortem operations, the way they were spread throughout the tissue might suggest otherwise.

In any case, subsequent experiments by the team found this bacterial phenomenon isn't restricted to human brains: research with mice also uncovered evidence of the brain microbiome in healthy mice, but not in a separate group of germ-free mice that were raised in isolators to be free from microorganisms.

It's definitely early days, but if future research can help explain the existence of this brain microbiome and how it affects brain cells, it could be a paradigm shift on a par with the discovery of the gut microbiome.

That would be a major step forward in neuroscience, helping cement other related findings in this area of research.

"There is much to investigate," psychiatrist Teodor Postolache from the University of Maryland in Baltimore, who wasn't involved with the study, told Science.

"I'm not very surprised that other things can live in the brain, but of course, it's revolutionary if it's so."

Consciousness Might Be a Result of Basic Physics, Say Researchers

noreply@blogger.com (Anonymous) — Sun, 11 Nov 2018 18:45:00 +0500

Why is my awareness here, while yours is over there? Why is the universe split in two for each of us, into a subject and an infinity of objects?

How is each of us our own center of experience, receiving information about the rest of the world out there? Why are some things conscious and others apparently not? Is a rat conscious? A gnat? A bacterium?

These questions are all aspects of the ancient "mind-body problem," which asks, essentially: What is the relationship between mind and matter? It's resisted a generally satisfying conclusion for thousands of years.

The mind-body problem enjoyed a major rebranding over the last two decades. Now it's generally known as the "hard problem" of consciousness, after philosopher David Chalmers coined this term in a now classic paper and further explored it in his 1996 book, "The Conscious Mind: In Search of a Fundamental Theory."

Chalmers thought the mind-body problem should be called "hard" in comparison to what, with tongue in cheek, he called the "easy" problems of neuroscience: How do neurons and the brain work at the physical level? Of course they're not actually easy at all.

But his point was that they're relatively easy compared to the truly difficult problem of explaining how consciousness relates to matter.

Over the last decade, my colleague, University of California, Santa Barbara psychology professor Jonathan Schooler and I have developed what we call a "resonance theory of consciousness."

We suggest that resonance – another word for synchronized vibrations – is at the heart of not only human consciousness but also animal consciousness and of physical reality more generally. It sounds like something the hippies might have dreamed up – it's all vibrations, man! – but stick with me.

All about the vibrations

All things in our universe are constantly in motion, vibrating. Even objects that appear to be stationary are in fact vibrating, oscillating, resonating, at various frequencies.

Resonance is a type of motion, characterized by oscillation between two states. And ultimately all matter is just vibrations of various underlying fields. As such, at every scale, all of nature vibrates.

Something interesting happens when different vibrating things come together: They will often start, after a little while, to vibrate together at the same frequency. They "sync up," sometimes in ways that can seem mysterious. This is described as the phenomenon of spontaneous self-organization.

Mathematician Steven Strogatz provides various examples from physics, biology, chemistry and neuroscience to illustrate "sync" – his term for resonance – in his 2003 book "Sync: How Order Emerges from Chaos in the Universe, Nature, and Daily Life," including:

When fireflies of certain species come together in large gatherings, they start flashing in sync, in ways that can still seem a little mystifying.
Lasers are produced when photons of the same power and frequency sync up.
The moon's rotation is exactly synced with its orbit around the Earth such that we always see the same face.

Examining resonance leads to potentially deep insights about the nature of consciousness and about the universe more generally.

Sync inside your skull

Neuroscientists have identified sync in their research, too. Large-scale neuron firing occurs in human brains at measurable frequencies, with mammalian consciousness thought to be commonly associated with various kinds of neuronal sync.

For example, German neurophysiologist Pascal Fries has explored the ways in which various electrical patterns sync in the brain to produce different types of human consciousness.

Fries focuses on gamma, beta and theta waves. These labels refer to the speed of electrical oscillations in the brain, measured by electrodes placed on the outside of the skull.

Groups of neurons produce these oscillations as they use electrochemical impulses to communicate with each other. It's the speed and voltage of these signals that, when averaged, produce EEG waves that can be measured at signature cycles per second.

Gamma waves are associated with large-scale coordinated activities like perception, meditation or focused consciousness; beta with maximum brain activity or arousal; and theta with relaxation or daydreaming.

These three wave types work together to produce, or at least facilitate, various types of human consciousness, according to Fries. But the exact relationship between electrical brain waves and consciousness is still very much up for debate.

Fries calls his concept "communication through coherence." For him, it's all about neuronal synchronization. Synchronization, in terms of shared electrical oscillation rates, allows for smooth communication between neurons and groups of neurons.

Without this kind of synchronized coherence, inputs arrive at random phases of the neuron excitability cycle and are ineffective, or at least much less effective, in communication.

A resonance theory of consciousness

Our resonance theory builds upon the work of Fries and many others, with a broader approach that can help to explain not only human and mammalian consciousness, but also consciousness more broadly.

Based on the observed behavior of the entities that surround us, from electrons to atoms to molecules, to bacteria to mice, bats, rats, and on, we suggest that all things may be viewed as at least a little conscious.

This sounds strange at first blush, but "panpsychism" – the view that all matter has some associated consciousness – is an increasingly accepted position with respect to the nature of consciousness.

The panpsychist argues that consciousness did not emerge at some point during evolution. Rather, it's always associated with matter and vice versa – they're two sides of the same coin.

But the large majority of the mind associated with the various types of matter in our universe is extremely rudimentary. An electron or an atom, for example, enjoys just a tiny amount of consciousness. But as matter becomes more interconnected and rich, so does the mind, and vice versa, according to this way of thinking.

Biological organisms can quickly exchange information through various biophysical pathways, both electrical and electrochemical. Non-biological structures can only exchange information internally using heat/thermal pathways – much slower and far less rich in information in comparison.

Living things leverage their speedier information flows into larger-scale consciousness than what would occur in similar-size things like boulders or piles of sand, for example. There's much greater internal connection and thus far more "going on" in biological structures than in a boulder or a pile of sand.

Under our approach, boulders and piles of sand are "mere aggregates," just collections of highly rudimentary conscious entities at the atomic or molecular level only.

That's in contrast to what happens in biological life forms where the combinations of these micro-conscious entities together create a higher level macro-conscious entity. For us, this combination process is the hallmark of biological life.

The central thesis of our approach is this: the particular linkages that allow for large-scale consciousness – like those humans and other mammals enjoy – result from a shared resonance among many smaller constituents.

The speed of the resonant waves that are present is the limiting factor that determines the size of each conscious entity in each moment.

As a particular shared resonance expands to more and more constituents, the new conscious entity that results from this resonance and combination grows larger and more complex.

So the shared resonance in a human brain that achieves gamma synchrony, for example, includes a far larger number of neurons and neuronal connections than is the case for beta or theta rhythms alone.

What about larger inter-organism resonance like the cloud of fireflies with their little lights flashing in sync? Researchers think their bioluminescent resonance arises due to internal biological oscillators that automatically result in each firefly syncing up with its neighbors.

Is this group of fireflies enjoying a higher level of group consciousness? Probably not, since we can explain the phenomenon without recourse to any intelligence or consciousness.

But in biological structures with the right kind of information pathways and processing power, these tendencies toward self-organization can and often do produce larger-scale conscious entities.

Our resonance theory of consciousness attempts to provide a unified framework that includes neuroscience, as well as more fundamental questions of neurobiology and biophysics, and also the philosophy of mind. It gets to the heart of the differences that matter when it comes to consciousness and the evolution of physical systems.

Here's How an Allergic Reaction Can Shut Your Body Down in Minute

noreply@blogger.com (Anonymous) — Sun, 11 Nov 2018 18:40:00 +0500

Allergies can be deadly. But despite how common they are, scientists still don't fully understand what happens inside the body to trigger anaphylactic shock - a terrifying and rapid reaction that can result in death.

But they're getting closer. For the first time, scientists have identified a mechanism in mice that sends a body into full-on panicking shutdown when exposed to even the smallest amount of an allergen.

An allergy occurs when the body's immune system mistakenly identifies a particular substance - such as peanuts, or shellfish - as harmful, and fires up to fight it, potentially triggering anaphylaxis.

Anaphylaxis is incredibly dangerous. It's the most serious of all the allergic reactions, and it can happen incredibly quickly. Within minutes of allergen exposure, the patient's immune system can kick into action - causing facial swelling, racing heart, rashes and hives, and the inability to breathe.

We know that a type of immune cell called a mast cell plays a central role in anaphylaxis. When an allergen is detected, these cells release inflammatory molecules such as histamines, which play an important role in the inflammatory response, one of the body's defense mechanisms.

But until now, exactly how how the presence of the allergen is communicated between mast cells, and so quickly, had been something of a mystery. The new study implicates immune cells called dendritic cells.

"The central finding is that dendritic cells, which are key players in allergy development, also play a direct role in triggering anaphylactic shock," said immunologist and senior author Soman N. Abraham of Duke University.

To figure this out, the researchers lowered the levels of different types of immune cells in mice, then injected them with toxins to induce anaphylaxis.

They found that the mast cells on their own weren't able to pick up allergens. And when a certain type of cell - the dendritic cell - was reduced, the mice didn't experience anaphylactic symptoms.

When they looked closer with two-photon microscopy, the researchers observed these dendritic cells in action. They're called dendritic cells because of their dendrites, which are long tendrils they can use to probe into other cells.

As they sit on the exterior surface of blood vessels, they use these dendrites to penetrate the cell wall, seeking out invading substances.

Upon detection of an allergen, they communicate its presence to any surrounding mast cells - but the way they do this is pretty weird.

Usually, when dendritic cells detect antigens, they internalise them, process them, and present information about the antigen on their surface to communicate it to the immune system's T cells so they can get to work.

These dendritic cells fish the allergen out of the blood vessels, then send it out via tiny bubbles called microvesicles, which bud from the surface of dendritic cells.

"In addition to their well-known capacity to internalise, process and present antigens to immune cells, dendritic cells now appear to actively distribute antigens they have acquired to surrounding immune cells even before they are internalised," Duke University immunologist Hae Woong Choi explained.

This method spreads information much more quickly, and to a larger number of cells. And when they receive the microvesicles, the mast cells are galvanised into action, filling the blood stream with histamines and other inflammatory mediators, kicking off anaphylaxis.

Obviously, we don't know if it works exactly the same in humans. And nor do we know if these dendritic cells are somehow beneficial. These things will need to be figured out - but once they are, this research could help develop a new way to prevent anaphylaxis.

"While it's detrimental in the context of allergens, this function might be needed to fight diseases and actually be helpful," Abraham said.

"Maybe these dendritic cells are designed to detect blood-borne parasites, viruses or bacteria, so we need to understand any other circumstances that activate them before contemplating shutting them down or impeding their activity."

There's Early Evidence Poaching Is Causing Elephants to Evolve Away From Having Tusk

noreply@blogger.com (Anonymous) — Sun, 11 Nov 2018 18:29:00 +0500

Poachers that kill or maim elephants for their ivory tusks have decimated world elephant populations.

According to new research, that activity has placed such a strain on elephant populations in Mozambique that it's forcing the hand of evolution. Historically, only 2 to 4 percent of female African elephants were naturally tuskless — and now nearly a third of the population is

Pachyderm's Canon

That's according to as-yet-unpublished research by Joyce Poole, an elephant behavior expert.

Poole told National Geographic that "once there's been heavy poaching pressure on a population, then the poachers start to focus on the older females as well," and that over time, "with the older age population, you start to get this really higher proportion of tuskless females."

Trunk Club

Other researchers have corroborated the phenomenon outside Mozambique. In the early 2000s, according to National Geographic, 98 percent of the nearly 200 female elephants in South Africa's Addo Elephant National Park had no tusks.

The phenomenon is a bleak condemnation of the cruelty of poaching — but also a stark example of how pressure on an ecosystem can lead to incredible evolutionary adaptations.

These Are The 'Smartest' Dog Breeds, According to a Canine Psychologist

noreply@blogger.com (Anonymous) — Sun, 11 Nov 2018 17:12:00 +0500

There's no easy way to rate dog intelligence. It can be focused on more than one thing.

As canine psychologist Stanley Coren wrote back in the '90s, there's adaptive intelligence (i.e., figuring stuff out), working intelligence (i.e. following orders), and instinctive intelligence (i.e. innate talent) - not to mention spatial intelligence, kinesthetic intelligence, interpersonal intelligence, and more.

Indeed, as animal behaviourist Frans de Waal has argued, humans tend to judge animal intelligence in limited and unfair terms and often bungle the experiment.

While labs at Yale, Duke, and around the world are studying this question, for now, we do at least have data on one metric: working intelligence.

Coren, in his book, The Intelligence of Dogs, featured the results of a lengthy survey of 199 dog obedience judges.

The responses, he said, were remarkably consistent; however, he noted that many judges pointed out that there are exceptions in every breed and that a lot comes down to training.

Here's what he found:

Top tier - the brightest working dogs, who tend to learn a new command in less than five exposures and obey at least 95 percent of the time.

Dan Kitwood (Getty)

1. Border collie

2. Poodle

3. German shepherd

4. Golden retriever

5. Doberman pinscher

6. Shetland sheepdog

7. Labrador retriever

8. Papillon

9. Rottweiler

10. Australian cattle dog

Second tier - excellent working dogs, who tend to learn a new command in five to 15 exposures and obey at least 85 percent of the time.

Pmuths1956 (WikiMedia Commons)

11. Pembroke Welsh corgi

12. Miniature schnauzer

13. English springer spaniel

14. Belgian Tervuren

15. Schipperke, Belgian sheepdog

16. Collie Keeshond

17. German short-haired pointer

18. Flat-coated retriever, English cocker spaniel, Standard schnauzer

19. Brittany spaniel

20. Cocker spaniel, Nova Scotia duck tolling retriever

21. Weimaraner

22. Belgian Malinois, Bernese mountain dog

23. Pomeranian

24. Irish water spaniel

25. Vizsla

26. Cardigan Welsh corgi

Third tier - above-average working dogs, who tend to learn a new trick in 15 to 25 repetitions and obey at least 70 percent of the time.

27. Chesapeake Bay retriever, Puli, Yorkshire terrier

28. Giant schnauzer, Portuguese water dog

29. Airedale, Bouv Flandres

30. Border terrier, Briard

31. Welsh springer spaniel

32. Manchester terrier

33. Samoyed

34. Field spaniel, Newfoundland, Australian terrier, American Staffordshire terrier, Gordon setter, Bearded collie

35. American Eskimo dog, Cairn terrier, Kerry blue terrier, Irish setter

36. Norwegian elkhound

37. Affenpinscher, Silky terrier, Miniature pinscher, English setter, Pharaoh hound, Clumber spaniel

38. Norwich terrier

39. Dalmatian

Fourth tier - average working dogs, who tend to learn a new trick in 25 to 40 repetitions and obey at least 50 percent of the time.

Vadim Petrakov (Shutter Stock)

40. Soft-coated wheaten terrier, Bedlington terrier, Smooth-haired fox terrier

41. Curly-coated retriever, Irish wolfhound

42. Kuvasz, Australian shepherd

43. Saluki, Finnish Spitz, Pointer

44. Cavalier King Charles spaniel, German wirehaired pointer, Black-and-tan coonhound, American water spaniel

45. Siberian husky, Bichon Frise, English toy spaniel

46. Tibetan spaniel, English foxhound, Otterhound, American foxhound, Greyhound, Harrier, Parson Russel terrier, Wirehaired pointing griffon

47. West Highland white terrier, Havanese, Scottish deerhound

48. Boxer, Great Dane

49. Dachshund, Staffordshire bull terrier, Shiba Inu

50. Malamute

51. Whippet, Chinese shar-pei, Wirehaired fox terrier

52. Rhodesian ridgeback

53. Ibizan hound, Welsh terrier, Irish terrier

54. Boston terrier, Akita

Fifth tier - fair working dogs, who tend to learn a new trick in 40 to 80 repetitions and respond about 40 percent of the time.

Stephanie Keith (Getty)

55. Skye terrier

56. Norfolk terrier, Sealyham terrier

57. Pug

58. French bulldog

59. Brussels griffon, Maltese terrier

60. Italian greyhound

61. Chinese crested

62. Dandie Dinmont terrier, Vendeen, Tibetan terrier, Japanese chin, Lakeland terrier

63. Old English sheepdog

64. Great Pyrenees

65. Scottish terrier, Saint Bernard

66. Bull terrier, Petite Basset Griffon, Vendeen

67. Chihuahua

68. Lhasa apso

69. Bullmastiff

Sixth tier - the least effective working dogs, who may learn a new trick after more than 100 repetitions and obey around 30 percent of the time.

Capture Light (Shutter Stock)

70. Shih Tzu

71. Basset hound

72. Mastiff, beagle

73. Pekingese

74. Bloodhound

75. Borzoi

76. Chow chow

77. Bulldog

78. Basenji

79. Afghan hound

There are, again, exceptions. Coren talks in his book about a trainer who managed to win obedience competitions with multiple Staffordshire bull terriers (#49).

There are also, again, other ways of measuring intelligence.

Coren tells us about a Nova Scotia Duck Tolling Retriever (#20) he owned that was in some ways too smart for competitions.

"He was so bright and attentive that he read my every motion, head turn, and even the direction that I was looking with my eyes, as a command," he writes by email.

"That made him very difficult to compete with in obedience trials, since, for instance, a glance with my eyes in the direction of the high jump might be interpreted by him as a command and that would send him off, taking the jump beautifully of course, but nonetheless disqualifying us from that round of competition."

De Waal, in Are We Smart Enough to Know How Smart Animals Are? spoke in defence of the Afghan hound (#79), noting that they may not be unintelligent but rather independent-mined, stubborn, and unwilling to follow orders.

"Afghans," he wrote, "are perhaps more like cats, which are not beholden to anyone."

Scientists Just Engineered Human Heart Tissue That Beats Like The Real Thing

noreply@blogger.com (Anonymous) — Sun, 11 Nov 2018 17:04:00 +0500

If you have doubts about the progress scientists are making in growing tissuein the lab, check out this incredible artificial heart tissue that beats just like the real thing - it's both haunting and fascinating to watch.

The researchers grew the heart's atria – the upper chambers of the heart, which either pump blood into the ventricles or out to the rest of the body.

This artificial tissue can beat, express genes, and respond to drugs in a way that mimics a real human atrium, which means it could prove invaluable in developing treatments for related heart conditions such as atrial fibrillation.

This remarkable bit of lab engineering was based on human induced pluripotent stem cells or hiPCSs, which are stem cells generated directly from adult cells that can then be coached to develop into any other type of cell required.

"This is the first time that human atrial heart tissue has been generated in vitro from a principally unlimited source of hiPSCs," says one of the researchers, Marta Lemme from the University Medical Center Hamburg-Eppendorf in Germany.

"This could be useful both for academic laboratories and the pharmaceutical industry, because to test potential new drugs, we need to generate an in vitro model of atrial fibrillation. And the first step in that is to obtain cells that resemble human atrial cardiomyocytes."

Cardiomyocytes are the cells that make up the muscle of the heart or the cardiac muscle. What's special about these cardiomyocytes were they were developed to create 3D, beating heart tissue: that means properties allowing them to contract and relax, and to respond to drugs and electrical impulses.

The key was a vitamin A metabolite called all-trans retinoic acid, used to reprogram donor cells into a suitable, atrial-like form. Because the tissue matches the real heart so closely, it should be useful for everything from drug screening to disease analysis.

"A particular value of our study is the direct comparison of our 3D engineered heart tissue with native human atrial tissue obtained from patients on a molecular and functional level," says Lemme.

The main benefits of the research should be in the study of arrhythmia, or an irregular heartbeat. It comes in a variety of forms, but the most common is atrial fibrillation – that's where the heartbeat is often irregular and sometimes very fast, considerably higher than the usual upper limit of 100 beats when you're at rest.

It can lead to dizziness, shortness of breath, and tiredness, and is typically treated with drugs to control the heart rate or an operation called a catheter ablation that uses radiofrequency energy to destroy the part of the heart causing the abnormal rhythm.

But as realistic as this artificially grown human tissue looks when it's beating, the team behind the study thinks there's still plenty of room for improvement.

"These atrial muscle strips represent a great opportunity to model atrial fibrillation in the dish and test drugs," says Lemme. "Nevertheless, improvements can still be made to reach even higher similarity with the human atrial tissue."

"For us, the next step is to test various means to induce arrhythmias, study mechanisms of electrical remodeling of atrial fibrillation and test new potential drugs."

Your Lifestyle Could Be Giving You Type 2 Diabetes by Changing Your DN

noreply@blogger.com (Anonymous) — Sun, 11 Nov 2018 16:55:00 +0500

Changes to the expression of a gene responsible for managing important chemical messengers that keep glucose and fat metabolism in check could be behind the development of a number of cases of type 2 diabetes.

A new study has advanced earlier research that showed low levels of a protein that bound to insulin-like growth factors made it more likely that mice developed type 2 diabetes. By finding the same effect in humans, we might be able to spot the disease earlier, and maybe even prevent its onset.

Researchers from the German Institute of Human Nutrition Potsdam-Rehbruecke (DIfE) and the German Center for Diabetes Research (DZD) carried out a population-wide study on the back of their earlier studies on insulin-like growth hormone binding proteins and the genes that produce them.

Their findings suggest that for some people, type 2 diabetes could have its roots in the locking of just a single gene.

If you get your different diabetes muddled up, keep in mind type 1 is typically diagnosed early in life, and involves the loss of insulin-production thanks to the destruction of key pancreatic tissues.

Type 2, on the other hand, is a progressive illness that usually develops past middle age. It usually kicks in as a result of various dietary and lifestyle factors, though genetic influences can predispose many people to develop a resistance to insulin in the first place.

As convenient as these two categories are for the time being, diabetes is a complicated condition that we're only beginning to fully understand (and might need a complete rewrite anyway).

This new research shows just how complex the pathology behind type 2 diabetes could be.

Insulin is the usual suspect when it comes to glucose levels going away. It's the key that unlocks the door for glucose to enter cells and work its magic.

But there is another hormone that helps the body metabolise sugar, called insulin-like growth factor (IGF).

Various types of binding proteins grab onto IGF in the blood-stream and mediate its effects, helping fine tune not just the uptake of glucose, but the liver's production of fat and glycogen.

Changes to the production and distribution of these chemical handcuffs have been linked to the development of type 2 diabetes in the past, making IGF binding proteins an important target for researchers.

One binding protein in particular – IGFBP-2 – has been the subject of ongoing studies. Women who had higher concentrations of this protein in the blood were found to have a reduced risk of developing type 2 diabetes.

Studies carried out on mice suggested low levels of IGFBP-2 predisposed them to fatty liver disease, a condition closely associated with type 2 diabetes. This meant levels of the binding protein were low before the disease had taken hold.

Intriguingly, researchers had found evidence that the binding protein's gene had been silenced by an epigenetic switch – the DNA equivalent of a padlock that can be put in place for various reasons, typically environmental ones.

Their findings suggested that the gene for IGFBP-2 in the liver was edited early in life, setting the mice up for type 2 diabetes later.

Mice models are all well and good, but for human health research what we really need is to find similar evidence in people studies.

So the same research team used data collected as part of a previous study on German health, comprised of individuals aged between 35 and 65.

From just under 28,000 individuals, the researchers matched 300 subjects who had type 2 diabetes with 300 similar controls, and then compared levels of IGFBP-2. They also analysed epigenetic changes to the protein's gene in their blood.

Sure enough, having higher levels of IGFBP-2 was associated with a variety of factors, such as a lower BMI, smaller waist circumference, smaller fatty liver index, and a lower risk of type 2 diabetes.

But for the subjects with type 2 diabetes the same chemical padlock found in the diabetic mice was also more likely to appear, again suggesting that for many people, diabetes could be influenced, if not caused, by epigenetic changes early in life.

"This study is a good example of how translational research works: a clinical finding is taken up, analysed mechanistically in the laboratory and finally examined in a population-wide study," says lead scientist Annette Schürmann.

Not only does this help explain some of the complexity behind the condition, it could lead to better ways of diagnosing or even preventing the disease - long before the trouble begins.

"In the future, our findings may help to identify risk potentials for type 2 diabetes even earlier and help to counteract the disease with preventive measures," says Schürmann.

Roughly 1 in 11 adults worldwide have some form of diabetes, 90 percent of which is of the type 2 variety. Those numbers are steadily going up as well.

Researchers Think They've Glimpsed What Sadness Looks Like in The Brai

noreply@blogger.com (Anonymous) — Sun, 11 Nov 2018 16:41:00 +0500

But until recently science, neuroscientists knew little about what the melancholy emotion looked like from a scientific perspective.

They knew the part of the brain called the amygdala played a role, but brain scans weren't fast enough to catch what was happening during moment-to-moment fluctuations in emotional state.

Tears Don't Fall

That changed when a team of researchers at the University of California asked 21 epilepsy patients to carefully log their moods.

Each of those patients had been previously outfitted with tiny wires that monitored their brains' electrical activity, making it easy for the UC team to look for patterns between their brain activity and mood.

In a new paper, published Thursday in the journal Cell, the researchers report an unexpected finding.

In most of the patients, they noticed a link between sadness and a particular neural circuit that connected the amygdala, which deals with emotional fluctuations, with the hippocampus, which helps store memories.

Misery Business

It makes sense, researcher Vikaas Sohal told NPR, that there would be a link between sadness and remembering bad things that have happened to you — though they haven't yet confirmed that that's what's going on.

In fact, it's still not clear whether the circuit between emotion and memory causes the feeling of sadness or the other way around.

Still, Sohal said he hopes the finding will bring comfort to patients in the form of a new explanation for what's going on during times of sorrow:

"As a psychiatrist, it's incredibly powerful to just be able to say to patients, 'Hey, I know there's something happening in your brain when you're feeling down.'"

An Astronaut on The ISS Has Caught an Eerie Orange Glow Above Earth

noreply@blogger.com (Anonymous) — Fri, 9 Nov 2018 14:14:00 +0500

The sky above Earth is never completely dark. Even at night a soft glow emanates from the rim of the upper atmosphere. It's always there, right above us, but it's tricky to see from Earth.

Lucky for us, an astronaut on board the International Space Station has captured the spectacular effect from space.

The photograph shows the curve of our planet, wrapped in a bubble of orange-coloured light known as an airglow.

It was taken in a fortuitous moment last month, while the ISS was passing over Australia, more than 250 miles (400 km) below.

(NASA)

Airglow is caused when nitrogen and oxygen in the atmosphere interact with ultraviolet radiation from the sun. The reaction excites atoms in the atmosphere, causing them to bang into each other and emit colourful light.

From space, airglow makes it look as though our planet is wrapped in a blanket of soft light, commonly green but sometimes other colours too.

From Earth, it looks sort of like an aurora, although it is fundamentally different and can be see all over the world. The effect tinges the sky with a whole rainbow of different colours and combinations. Sometimes, bands of light can also be seen crossing the sky.

Airglow is spectacular to behold, but it's also intriguing to scientists because it sits in the exact spot where Earth and space meet.

This dynamic zone can teach scientists a lot about how space weather is connected to weather here on Earth.

New York's Beloved, Handsome Duck Is Back After a Mysterious Disappearance

noreply@blogger.com (Anonymous) — Fri, 9 Nov 2018 14:11:00 +0500

At first glance, you might miss it. But among Central Park's usual waterfowl crowd, there appears to be a new addition. And people are flocking to see him.

A single, male Mandarin duck flaunts his multi-coloured feathers as he swims out among a posse of mallards and wood ducks. He's not a local, and it's a mystery as to how he arrived.

The hypothesis that he escaped from a zoo or sanctuary has been ruled out so far. And since ducks aren't allowed as pets in New York City, that theory also stands on shaky ground.

The duck was first spotted about a month ago by birdwatchers who frequent the park, but he fell off the grid for two weeks and reappeared a week or so ago.

Since then, he's been traversing different bodies of water throughout the park. The twitter account Manhattan Bird Alert tweets out the location of the duck from time to time.

Huge crowds from all over New York City, of all ages, have turned up in the past weekend to see the duck.

The Mandarin duck's favourite hang-out spot, the pond by 59th street and 5th avenue, drew a crowd that lined the entire perimeter of the waterfront on Saturday.

Spectators wait patiently, with cameras, binoculars, and scopes for the duck to leave his asylum on a shaded rock island that sits at the visually obscured part of the pond-where he preens his resplendent coat-and swim out to greet his fans.

The duck has become Twitter famous as well, ever since New York Times that drew in a flurry of shares all over social media.

Mandarin ducks tend to be a bit introverted by nature, according The Wildlife Trusts, and like to hide behind overhanging willows. They eat water plants, rice, grains, pests, and some small fish and mollusks, and live for about 6 years.

Mandarin ducks prefer wooded freshwater ponds or marshes. That's due to a quirk these ducks have – they like to nest in holes high up in trees. After the ducklings hatch, the mother duck coaxes them to jump down from the nest. They share this trait with the wood duck, a close relative.

(Charlotte Hu/Business Insider)

Male and female Mandarin ducks share an elaborate courtship ritual before forming monogamous pairs at the beginning of winter. Because of this, Mandarin ducks in China are a symbol of love and healthy relationships.

The Central Park Mandarin duck, however, still seems to be living out his bachelor days leisuring by the pond-side and bathing in attention.

In the wake of his growing celebrity, the New York City Parks Twitter account tweeted a request to visitors, asking them to "please remember to enjoy our new friend from a distance and do not feed him.

Ancient DNA Has Revealed Surprising Connections Between The First People of The Americas

noreply@blogger.com (Anonymous) — Fri, 9 Nov 2018 14:02:00 +0500

Who were the first Americans? While we have some rough ideas, the answer to this question has long been up for debate.

Now, comparisons between two extraordinary sets of ancient American remains have added rich detail to the spread of ancient human populations through the New World more than 13,000 years ago. And it shows a surprising and far-reaching connection between native North, South, and Central Americans.

What started as a simple story of migration is quickly turning into an intricate web of movement and cross-pollination, revealing connections that stretch not just deep into South America, but perhaps around the world.

Two separate research groups have compared genetic sequences taken from a range of specimens collected from Alaska to Patagonia to reveal new details on the expansion of native American populations.

The 'old' story on the arrival of humans to the American continents has been a fairly simple one, largely thanks to a relative lack of information.

Small groups of people slowly journeyed across the Bering Strait as the last great ice age melted away more than 20,000 years ago, taking thousands of years to branch out across the land and eventually into South America. That much we know.

The image we're left with is an inverted tree, with a solid trunk in the north and branches diverging and blooming with new cultures.

Of course, the story of human settlement was never going to be that straight forward. The map of human evolution around the globe, as we're learning, is anything but a one-way street ending in cul-de-sacs.

But while the beginning and end points are clear, the timing and precise movement of family lineages has been left to our imagination.

The remains of a toddler who died in what is today Montana some 12,700 years ago has provided two groups of investigators with a solid landmark to work from in their efforts to identify relationships between diverse populations.

So-called Anzick child is the oldest known burial in North America, discovered alongside tools representing a people who had until recently been long considered the first occupants of the continent, the Clovis culture.

One group of researchers compared DNA sequences from the Anzick child with those taken from another record holding specimen – the continent's oldest mummified remains.

Spirit Cave mummy is a body that was unearthed in northwest Nevada in the 1940s, and has contentiously been thought to represent an even older culture than the Clovis, based on its own unique tools.

The 10,600 year old remains were quickly claimed by the Fallon Paiute-Shoshone Tribe as an ancestor deserving repatriation, with a subsequent genetic analysis demonstrating it was more closely related to modern Native Americans than any other population around the globe.

Researchers have now identified a genetic link between the Anzick child and the Spirit Cave mummy, arguing even if they were culturally distinct, genetically they shared a relatively recent set of ancestors.

Drawing a line between Anzick child and the Spirit Cave mummy was just the first step. The team also showed there were links between the Anzick child's remains and 10,000 year old remains from Lagoa Santa in Brazil, with a common ancestor dating back around 14,000 years ago - a link between the Clovis culture and South American that wasn't expected.

A second international team of researchers independently analysed an astonishing 49 sets of remains from Central and South America dating as far back as around 11,000 years, also using Anzick child as a reference point.

They identified even closer relationships between the Clovis remains and 9,300 to 10,900 year old remains from Brazil, Chile, and Belize.

"These [findings] are fascinating as they open new gateways into archaeological and genetic research," co-author Nathan Nakatuska explained to Sarah Sloat at Inverse.

"It was previously not known that the Clovis culture extended into South America, and it is incredible that these people were able to migrate all the way through North, Central, and South America. In addition, the new migration into the Southern Andes was not previously known, and we are unsure what historical events led to this."

Solving the mystery of why such rapid separations occurred is now the big question. Making matters even more complicated, both teams identified further waves of genes entering populations spreading north and south over the millennia.

None of these movements replaced existing populations, but rather show a melting pot of migrations that ebbed and flowed. That inverted tree idea is quickly being replaced by a far more complex network, which has exploded and settled in multiple directions over thousands of years.

Stranger still is the hint of Australasian ancestry slipped in among the genes, hinting at a deeper mystery that so far has few clues to go on.

"How did it get there? We have no idea,"

geneticist José Víctor Moreno-Mayar of the University of Copenhagen

told Lizzie Wade at Science Magazine.

There's little doubt that with better technology and more genetic samples we'll continue to unveil the rich tapestry of early American cultures, one that could stretch further than we ever imagined.

No, 3 Giant Asteroids Aren't 'Skimming' Earth This Weekend to Put You Out of Your Misery

noreply@blogger.com (Anonymous) — Fri, 9 Nov 2018 13:57:00 +0500

According to some alarming tabloid headlines, three giant asteroids are skimming by Earth this weekend - one as long as a blue whale!

Here's what's really going on: there are a number of asteroids about to zip through Earth's general neighbourhood, according to a NASA asteroid watch website.

But we're not in any danger whatsoever - they're all at or well outside the Moon's orbit. Comfortingly, one has already safely passed by.

Asteroids are streaming past us every day, as a matter of fact, although many of them are too wee to be detectable, or even potentially hazardous.

However, NASA keeps an eye out for the bigger chunks of space rock, just in case.

According to NASA's official Near-Earth Asteroids categories, anything smaller than around 140 metres (460 feet) isn't considered potentially hazardous.

By those metrics, the four asteroids about to pass by this weekend are absolute shrimpazoids.

Here they are (all times in GMT):

Asteroid 2018 VA2 will make its closest approach at 1:01 am GMT on Friday, 9 November at a distance of 718,070 kilometres (446,188 miles). It's 10 to 23 metres (33 to 75 feet) in diameter. Phew, missed us!
Asteroid 2018 VS1 will make its closest approach at 2:03 pm on Saturday, 10 November at a distance of 1.39 million kilometres (865,418 miles). It's 13 to 28 metres (43 to 92 feet) in diameter.
Asteroid 2018 VR1 will make its closest approach at 2:19 pm on Saturday, 10 November at a distance of 5.06 million kilometres (3.15 million miles). It's 14 to 30 metres (46 to 98 feet) in diameter.
Asteroid 2018 VX1 will make its closest approach at 6:20 pm on Saturday, 10 November at a distance of 381,474 kilometres (237,037 miles). It's the closest, but the smallest, of all four, just skimming inside the Moon's average distance of 384,400 kilometres (238,855 miles), but only 7.9 to 18 metres (26 to 59 feet) in diameter

Next week there are some much bigger asteroids zipping past as they orbit the Sun, with 2018 UQ1 boasting a diameter of 110 to 250 metres (361 to 820 feet), and 2017 UL12 at 180 to 390 metres (590 to 1,280 feet).

But these are much farther out, at 9 and 16 times the average distance to the Moon respectively. So, really, you don't need to panic.

Now, Earth's asteroid safety measures aren't necessarily the best. One might even say they're nonexistent. But NASA is working on it Nasa wreck working on it. The detection system is undergoing constant improvement, and in 2021, NASA engineers are going to test a new method of deflecting rocks away from Earth.

In the meantime, comfort yourself with the knowledge that, although asteroids wind up meeting Earth with relative frequency, most of the time no one gets hurt.

And all of next week's asteroids are going to sail harmlessly by, with no one but asteroid watchers even seeing them in the sky. If you have a telescope, maybe you can try to catch them yourself.

Satellite Data Has Revealed Relics of Lost Continents Hiding Under Antarctica

noreply@blogger.com (Anonymous) — Fri, 9 Nov 2018 13:49:00 +0500

Of all our planet's continents, we know the least about the icy landmass of Antarctica. Now, scientists have used satellite imagery to peer into Earth's tectonics, revealing the hidden structures of Antarctica as part of their work.

Due to its remote location and abundance of ice, charting the geological characteristics of Antarctica is tricky, but the Gravity Field and Steady-State Ocean Circulation Explorer (GOCE) satellite can see what other satellites can't – by precisely measuring the pull of Earth's gravity to map out hidden terrain.

GOCE crashed out of orbit after running out of fuel in 2013, but scientists are still poring over the data it collected. The researchers say it offers new insights into how Antarctica was formed, and how plate tectonics can function, as you can see in the video below.

"In East Antarctica we see an exciting mosaic of geological features that reveal fundamental similarities and differences between the crust beneath Antarctica and other continents it was joined to until 160 million years ago," says one of the team, Fausto Ferraccioli from the British Antarctic Survey.

Antarctica was once part of the supercontinent Gondwana, which began to disintegrate some 130 million years ago, although the bond between Antarctica and Australia held together as recently as 55 million years ago.

By combining GOCE readings with seismological data, the researchers were able to create 3D maps of Earth's lithosphere, made up of the crust and the molten mantle beneath. That lithosphere includes mountain ranges, ocean backs, and rocky zones called cratons – the leftovers of ancient continents embedded incontinents as we know them today

"The satellite gravity data can be combined with seismological data to produce more consistent images of the crust and upper mantle in 3D, which is crucial to understand how plate tectonics and deep mantle dynamics interact," says one of the researchers, Jörg Ebbing from Kiel University in Germany.

The GOCE satellite circled our planet for over four years, from March 2009 to November 2013. During that time it got unusually close to Earth – an altitude of just 225 km (140 miles) – to maximise the accuracy of its measurements.

The International Space Station, by comparison, is about two times farther away from Earth's surface.

Among the findings from the new study was the discovery of a thinner crust and lithosphere under West Antarctica compared to East Antarctica (above) – the latter has a mosaic of older cratons interspersed with thinner regions of rock, similar to India and Australia, which it was once joined to.

And the data is useful for more than just tracing the remnants of ancient continents across the past 200 million years: It can be used to help figure out how ice sheets above the underlying terrain might react to warmer temperatures.

With so many variables to consider, predicting how ice melt might progress across Antarctica is a real challenge, so any help scientists can get will be welcome. GOCE is still proving its use long after its mission ended.

"These gravity images are revolutionising our ability to study the least understood continent on Earth, Antarctica,"

says Ferraccioli.

A Solar Storm Detonated Dozens of US Sea Mines, Declassified Navy Documents Reveal

noreply@blogger.com (Anonymous) — Fri, 9 Nov 2018 13:39:00 +0500

An extraordinary account of the impact space weather had on military operations in Vietnam in 1972 was found buried in the US Navy archives, according to a newly published article in Space Weather.

On August 4, 1972, the crew of a US Task Force 77 aircraft flying near a naval minefield in the waters off Hon La observed 20 to 25 explosions over about 30 seconds. They also witnessed an additional 25 to 30 mud spots in the waters nearby.

Destructor sea mines had been deployed here during Operation Pocket Money, a mining campaign launched in 1972 against principal North Vietnamese ports.

There was no obvious reason why the mines should have detonated. But it has now emerged the US Navy soon turned its attention to extreme solar activity at the time as a probable cause.

The more we can understand the impact of such space weather on technology then, the better we can be prepared for any future extreme solar activity.

A solar theory

As detailed in a now declassified US Navy report, the event sparked an immediate investigation about the potential cause(s) of the random detonations of so many sea mines.

The sea mines deployed had a self-destruct feature. But the minimum self-destruct time on these mines was not for another 30 days, so something else was to blame.

On August 15, 1972, the Commander in Chief of the US Pacific Fleet, Admiral Bernard Clarey, asked about a hypothesis that solar activity could have caused the mine detonations.

Many of the mines deployed were magnetic influence sea mines that were designed to detonate when they detected changes in the magnetic field.

Solar activity was then well known to cause magnetic field changes, but it wasn't clear whether or not the Sun could cause these unintentional detonations.

Solar flares

Early August in 1972 saw some of the most intense solar activity ever recorded.

A sunspot region, denoted MR 11976, set off a series of intense solar flares(energetic explosions of electromagnetic radiation), coronal mass ejections (eruptions of solar plasma material that typically accompany flares) and clouds of charged particles travelling close to the speed of light.

Those conducting the investigation into the mine incident visited the Space Environment Laboratory at the National Oceanographic and Atmospheric Administration (NOAA) near Boulder, Colorado, to speak to space scientists.

One of the scientists at NOAA at the time was the now Emeritus Professor Brian Fraser, from Australia's Newcastle University, and it's an event he told me he remembers well:

I was on my first sabbatical leave at NOAA working with Wallace (Wally) Campbell's group, and one day in Wally's office I noticed a group of US Navy brass hat gentlemen and a couple of dark suits.

Brian said he had later quizzed Wally on what was going on, and Wally explained they were concerned about geomagnetic field changes triggering sea mines laid in Hai Phong, North Vietnam.

There was no mention whether or not they had exploded but maybe Wally was being coy. And of course it was all probably top secret then.

The outcome of this investigation, as stated in the declassified US Navy report, detailed "a high degree of probability" that the Destructor mines had been detonated by the August solar storm activity.

Solar interference

Solar storms cause strong magnetic field fluctuations, which impact large power grid infrastructure, particularly in the high-latitude regions beneath the northern and southern auroras.

The storms of early August 1972 were no different. There were numerous reports across North America of power disruptions and telegraph line outages.

Now that light has been shone on the impact of these events on sea mine operations in 1972, the scientific community has another clear example of space weather impacts on technologies.

The intensity of the early August activity peaked when an X-class solar flare at 0621 UT August 4, 1972, launched an ultra-fast coronal mass ejection that reached Earth in the record time of 14.6 hours. The solar wind normally takes two to three days to reach Earth.

Scientists think that the previous slower ejections from earlier flares had cleared the path for this fast disturbance, similar to what was observed by the STEREO spacecraft in July 2012.

It's the impact of this fast disturbance in the solar wind on the Earth's magnetosphere that probably caused the detonation of the Destructor mines.

Using the past to predict the future

The Dst index, measured in nano-Tesla (nT), is a typical measure of the disturbance level in the Earth's magnetic field – the more negative, the more intense the storm.

Some recent extreme solar storms, according to this scale, include the 2015 St Patrick's Day storm (-222 nT) and the 2003 Halloween storm (-383 nT).

Interestingly, the extreme activity in August 1972 was far less intense on this scale, only weighing in at -125 nT.

Exactly why this storm reached extreme level on some measures, such as its high speed from the Sun, but not on the typical Dst scale is a topic of significant discussion within the scientific literature.

Given the complexities of this event, this new paper lays out a grand challenge to the space weather community to use our modern modelling techniques to reexamine this solar event. Hopefully, under

Children Really Need to "Go Play Outside" to Prevent a Serious Eyesight Problem, Researchers War

noreply@blogger.com (Anonymous) — Fri, 9 Nov 2018 13:33:00 +0500

Getting children to play outside will benefit their eyesight and reduce their risk of becoming shortsighted, experts say.

Shortsightedness, or myopia, is becoming increasingly common the world over. By 2050, nearly 4.8 billion people will be affected by this visual disorder, which is about 2.8 billion more people than in 2010.

In China, where over 90 percent of young people are shortsighted, the problem is considered an epidemic.

But while those who wear glasses commonly blame their genes, genetics alone cannot explain this rapidly developing problem.

Instead, experts say we've been underestimating how our eyesight is affected by the environment, and the outdoors in particular.

Today, there is a growing body of research that suggests outdoor play time can lower a child's risk of developing myopia.

Not only does being outdoors force you to look further into the distance, exposure to outdoor lighting is also thought to be vital, since it appears to slow the axial growth of the eye. Excessive growth is what contributes to myopia.

One study found that even when a child has two nearsighted parents, if they don't spend enough time outdoors, the genetic threat of myopia increases to about 60 percent.

In light of these developments, experts now think that the environment has a greater role to play in myopia than genetics.

A recent study on twins adds even more weight to that idea. It suggests that there are several environmental factors that can influence the development of myopia.

"There is not much you can do about when your child is born … but periods indoors doing indoor activities does increase your risk of myopia," co-author Katie Williams, who studies disorders of the eye at King's College London, told The Guardian.

"A healthy balance of time outdoors and a balance during early education is important."

The research followed 1,991 twins, born between 1994 and 1996 in the UK, using data from the twins early development study.

For the first sixteen years of life, the researchers analysed each child's development, behaviour and education through questionnaires and tests, as well as collecting eye tests.

Interestingly, the study pinpointed four major environmental factors that are linked to myopia, and some of them were quite unexpected.

For instance, the study found children born by fertility treatment were 25-30 percent less likely to develop myopia by their mid-teens.

"This could, in part, be related to the fact that infants born following fertility treatment tend to have a lower birth weight and shorter gestation and have, in some but not all studies, developmental delay and reduced cognitive scores," the authors write.

Another part of the study found that those born during the summer were twice as likely to develop myopia - most likely because they start going to school younger than many of their peers.

Plus, for every higher level of education the mother had, the odds of the teenager having the condition rose by 33 percent. This could have something to do with the link between intelligence and myopia, although social factors like class and wealth probably also play a role.

And then, of course, there's technology. In the twin study, the hours spent playing computer games in early adolescence increased the odds of becoming myopic, too.

Although, this isn't simply because screen time is bad for your eyes (and it most certainly is). It's also a reflection of how little time we are spending outdoors - a relatively modern phenomenon that has been found to harm eye development.

"The increased [device screen time] resulting from gaming, social media, and digital entertainment has led to a rise in sedentary behaviour, poor diet and a lack of outdoor activity," the authors suggest.

The researchers reiterate, however, that these environmental factors are only correlated with myopia. And, as such, they do not necessarily causes hortsightedness.

But there's another part of the study that is perhaps even more limiting. The research was conducted on children born in the 90s, before the age of smartphones and other hand held devices.

Nowadays, with our eyes glued to the screen no matter where we are - even if it's outdoors - the problem is likely even worse.

"The rapid adoption of smart devices in children adds a new dimension to how we define and quantify near-work activity," the authors conclude.

"The role of smart devices, quantified as device screen time must also be investigated."

Scientists Develop Liquid Fuel That Can Store The Sun's Energy For Up to 18 Years

noreply@blogger.com (Anonymous) — Thu, 8 Nov 2018 14:57:00 +0500

No matter how abundant or renewable, solar power has a thorn in its side. There is still no cheap and efficient long-term storage for the energy that it generates.

The solar industry has been snagged on this branch for a while, but in the past year alone, a series of four papers has ushered in an intriguing new solution.

Scientists in Sweden have developed a specialised fluid, called a solar thermal fuel, that can store energy from the sun for well over a decade.

"A solar thermal fuel is like a rechargeable battery, but instead of electricity, you put sunlight in and get heat out, triggered on demand," Jeffrey Grossman, an engineer works with these materials at MIT explained to NBC News.

The fluid is actually a molecule in liquid form that scientists from Chalmers University of Technology, Sweden have been working on improving for over a year.

This molecule is composed of carbon, hydrogen and nitrogen, and when it is hit by sunlight, it does something unusual: the bonds between its atoms are rearranged and it turns into an energised new version of itself, called an isomer.

Like prey caught in a trap, energy from the sun is thus captured between the isomer's strong chemical bonds, and it stays there even when the molecule cools down to room temperature.

When the energy is needed - say at nighttime, or during winter - the fluid is simply drawn through a catalyst that returns the molecule to its original form, releasing energy in the form of heat.

"The energy in this isomer can now be stored for up to 18 years," says one of the team, nanomaterials scientist Kasper Moth-Poulsen from Chalmers University.

"And when we come to extract the energy and use it, we get a warmth increase which is greater than we dared hope for."

A prototype of the energy system, placed on the roof of a university building, has put the new fluid to the test, and according to the researchers, the results have caught the attention of numerous investors.

(Chalmers University of Technology)

The renewable, emissions-free energy device is made up of a concave reflector with a pipe in the centre, which tracks the Sun like a sort-of satellite dish.

The system works in a circular manner. Pumping through transparent tubes, the fluid is heated up by the sunlight, turning the molecule norbornadiene into its heat-trapping isomer, quadricyclane. The fluid is then stored at room temperature with minimal energy loss.

When the energy is needed, the fluid is filtered through a special catalyst that converts the molecules back to their original form, warming the liquid by 63 degrees Celsius (113 degrees Fahrenheit).

The hope is that this warmth can be used for domestic heating systems, powering a building's water heater, dishwasher, clothes dryer and much more, before heading back to the roof once again.

The researchers have put the fluid through this cycle more than 125 times, picking up heat and dropping it off without significant damage to the molecule.

"We have made many crucial advances recently, and today we have an emissions-free energy system which works all year around," says Moth-Poulsen.

After a series of rapid developments, the researchers claim their fluid can now hold 250 watt-hours of energy per kilogram, which is double the the energy capacity of Tesla's Powerwall batteries, according to the NBC.

But there's still plenty of room for improvement. With the right manipulations, the researchers think they can get even more heat out of this system, at least 110 degrees Celsius (230 degrees Fahrenheit) more.

"There is a lot left to do. We have just got the system to work. Now we need to ensure everything is optimally designed," says Moth-Poulsen.

If all goes as planned, Moth-Poulsen thinks the technology could be available for commercial use within 10 years.

NASA Photo Shows The Wreck of a 'Flying Saucer', But The Real Story Is Even More Amazing

noreply@blogger.com (Anonymous) — Thu, 8 Nov 2018 14:28:00 +0500

Any species reaching for the stars is bound to have its fingertips singed. Probably more than once.

One of NASA's latest posts on the Astronomy Picture of the Day website is an iconic reminder of the mishaps in our spacefaring history.

"A flying saucer from outer space crash-landed in the Utah desert after being tracked by radar and chased by helicopters," states the photo description, although NASA is not hinting at an alien visit here.

The banged-up dish, half-buried in the desert sand, was actually the return capsule of the Genesis spacecraft. And it wasn't supposed to touch down in such a brutal way.

Launched on 8 August 2001, the Genesis mission was the space agency's ambitious effort to send a spacecraft into our home star's solar wind, gather samples, and return them to Earth.

By gathering data on the composition of the charged particles streaming from the Sun's corona, researchers hoped to precisely determine the composition of the star, and learn more about the elements that were around when the Solar System's planets were formed.

To bring us solar wind samples, the Genesis craft was equipped with a sample return capsule holding a canister of solar wind materials, gathered when the craft spent two years orbiting Lagrange point 1 - one of the spots in space where the gravity from Earth and Sun are precisely balanced.

The craft captured the solar wind by folding out a series of collector arrays, each loaded with high-purity materials such as aluminium, sapphire, silicon, and even gold.

Artist rendering of the spacecraft with its arrays folded out (NASA/JPL-Caltech)

"The materials we used in the Genesis collector arrays had to be physically strong enough to be launched without breaking; retain the sample while being heated by the Sun during collection; and be pure enough that we could analyse the solar wind elements after Earth-return," project scientist Amy Jurewicz explained on 3 September 2004.

Five days later, that sample capsule and its precious arrays smashed into the ground in Utah, at an estimated speed of 310 km/h (193 mph).

(USAF 388th Range Sqd., Genesis Mission, NASA)

What was supposed to happen was rather different - 127 seconds after re-entering the atmosphere, a mortar aboard the capsule would blow, releasing a preliminary parachute for slowing and stabilising the descent.

Then, a main parachute was to inflate, providing the capsule with a gentle descent into the Utah Test and Training Range.

In the crash photo, you can see helicopters - they were hovering nearby, ready to snag the capsule mid-air and ferry it directly to a cleanroom to avoid contamination of the samples.

Neither of those parachutes deployed.

After a thorough investigation, the error was traced back to a set of sensors, barely the size of the metallic end of a pencil. They had been installed backwards.

These tiny devices were supposed to detect the increasing g-forces as the capsule plummeted towards the ground, and trigger the deployment of the parachutes.

As you can imagine, the crash led to severe damage, breaking several of the arrays and contaminating the precious cargo within.

Once the sample capsule was retrieved from the heart-sinking site of its demise, the project team set about to retrieve anything that could still be recovered and studied.

One of the Genesis team, Karen McNamara, inspects the damage on the capsule (NASA)

Thankfully, the Genesis mission wasn't completely ruined, even after such a dramatic arrival of the sample capsule. Some of the sturdy collector materials survived, and researchers managed to clean the surfaces without disturbing the solar material embedded within.

Within three years, a series of papers were published on the Genesis findings. Thanks to the daring mission, we learned unprecedented details about the composition of the Sun and the elemental differences between our star and the inner planets of the Solar System.

"The Sun houses more than 99 percent of the material currently in our Solar System, so it's a good idea to get to know it better," Genesis principal investigator Don Burnett from California Institute of Technology said in 2011