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APOD: 2012 June 17 - Jupiter eclipsing the sun and its rings revealed by reflection

APOD: 2012 June 17 - Jupiter eclipsing the sun and its rings revealed by reflection | Amazing Science | Scoop.it

Pictured above is an eclipse of the Sun by Jupiter, as viewed from Galileo. Small dust particles high in Jupiter's atmosphere, as well as the dust particles that compose the rings, can be seen by reflected sunlight.

 

Jupiter's rings were discovered in 1979 by the passing Voyager 1 spacecraft, but their origin was a mystery. Data from the Galileo spacecraft that orbited Jupiter from 1995 to 2003 later confirmed that these rings were created by meteoroid impacts on small nearby moons. As a small meteoroid strikes tiny Adrastea, for example, it will bore into the moon, vaporize, and explode dirt and dust off into a Jovian orbit.

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Saberes Sin Fronteras OVS's curator insight, November 30, 2014 5:33 PM

Acceso gratuito a documentos de las mejores universidades del mundo

♥ princess leia ♥'s curator insight, December 28, 2014 11:58 AM

WoW  .. Expand  your mind!! It has room to grow!!! 

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How Whales Became the Biggest Animals on the Planet

How Whales Became the Biggest Animals on the Planet | Amazing Science | Scoop.it

Whales are big. Really big. Enormously big. Tremendously big. Fin whales can be 140,000 pounds. Bowhead whales tip the scales at 200,000 pounds. And the big mama of them all, the blue whale, can reach a whopping 380,000 pounds — making it the largest animal to have ever lived on planet Earth.

 

 But for as long as whales have awed us with their great size, people have wondered how they became so colossal. In a study published Tuesday in the journal Proceedings of the Royal Society B, a team of researchers investigated gigantism in baleen whales, the filter-feeding leviathans that include blue whales, bowhead whales and fin whales. The marine mammals became jumbo-size relatively recently, they found, only within the past 4.5 million years. The cause? A climatic change that allowed the behemoths to binge-eat.

 

Whales have an interesting evolutionary history. They began as land-dwelling, hoofed mammals some 50 million years ago. Over several millions of years they developed fins and became marine creatures. Between about 20 million and 30 million years ago, some of these ancient whales developed the ability to filter-feed, which meant they could swallow swarms of tiny prey in a single gargantuan gulp. But even with this feeding ability, whales remained only moderately large for millions of years.

 

“But then all of a sudden — ‘boom’ — we see them get very big, like blue whales,” said Nick Pyenson, the curator of fossil marine mammals at the Smithsonian Institution’s National Museum of Natural History and an author of the paper. The researchers suspected that an environmental change happened during that time that essentially caused the baleen whales to bulk up. After some investigation, they found that this time period coincided with the early beginnings of when ice sheets increasingly covered the Northern Hemisphere.

 

Runoff from the glaciers would have washed nutrients like iron into coastal waters and intense seasonal upwelling cycles would have caused cold water from deep below to rise, bringing organic material toward the surface. Together these ecological effects brought large amounts of nutrients into the water at specific times and places, which had a cascading effect on the ocean’s food web.

 

Throngs of zooplankton and krill would gather to feast on the nutrients. They would form dense patches that could stretch many miles long and wide and be more than 65 feet thick. The oceans became the whales’ giant all-you-can-eat buffets. “Even though they had the anatomical machinery to filter-feed for a long, long time,” said Jeremy Goldbogen, a comparative physiologist from Stanford University and author of the paper, “it wasn’t until the ocean provided these patchy resources that it made bulk filter-feeding so efficient.” But that was only part of the equation.

 

“Plentiful food everywhere isn’t going to get you giant whales,” said Graham Slater, an evolutionary biologist at the University of Chicago and the study’s lead author. “They have to be separated by big distances.” Because the ecological cycles that fuel the explosions of krill and zooplankton occur seasonally, Dr. Slater said the whales must migrate thousands of miles from food patch to food patch. Bigger whale ancestors that had bigger fuel tanks had a better chance of surviving the long seasonal migrations to feed, while smaller baleen whales became extinct. If the food patches were not far apart, Dr. Slater said, the whales would have grown to a certain body size that was comfortable for that environment, but they would not be the giants we see today.

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The next era of Drones will be defined by 'Swarms'

The next era of Drones will be defined by 'Swarms' | Amazing Science | Scoop.it

Drones are getting tinier, cheaper, and will start swarming in huge groups like flocks of birds. These automated, flying robots are tiny, cheap, disposable. And in large groups, they could either save your life, or be the deadliest weapon since the machine gun.

 

Earlier this year, 300 drones assembled into an American flag in Lady Gaga’s Super Bowl halftime show, illuminating the night sky. And Intel is promoting their Shooting Star swarms as an alternative to fireworks. Chinese company eHang claimed the record for the biggest swarm, in a spectacular New Year show in which 1,000 drones formed a map of China and the Chinese character for 'blessings'.

 

Swarms could also check pipelines, chimneys, power lines and industrial plants cheaply and easily. Drone swarms may even have a place on the farm. They can spot plant disease and help manage water use, or spray pesticides and herbicides only in the exact spot needed, all working cooperatively to cover the area and fill in gaps.

 

Nikolaos Papanikolopoulos of the Centre for Distributed Robotics at the University of Minnesota is working on solar-powered drones that will ultimately work together to survey large swathes of farmland at low cost. “Their roles may include early detection of nitrogen deficiency, plant disease, and proper management of water resources,” says Papanikolopoulos.

 

Even the military is developing swarm technology. The US, for example, recently launched 103 small ‘Perdix’ drones from F/A-18 jets. These weigh a few hundred grams, and are released from dispensers normally used for flares. The 3D-printed Perdix drones are disposable, and are intended to suppress enemy air defences by acting as decoys or jammers or by locating radar so they can be destroyed.

 

The US Navy also aims to develop a swarm of drones that costs less than a missile. It’s developing software that allows sub-swarms to be split off for particular missions, or fresh drones to join the swarm seamlessly.

 

Another player is China, long the leader in small consumer drones. Chinese company DJI alone has around 70% of the global market, and now the Chinese military is seeing what they can do with this new technology. At an aerospace exhibition in December, state-owned China Electronics Technology Group Corporation (CETC) displayed a video of nearly 70 drones flying together. The drones flew in formation and collaborated in an intelligence-gathering mission. Those drones could also cooperate in a ‘saturation attack’ on an enemy missile launcher. They all dive in to attack simultaneously from different directions – far too many at once for the defenders to stop.


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prgnewshawaii's curator insight, May 19, 3:54 PM

The mixed blessing of the drone...a device that can do good or evil, depending on who programs and uses them.

Russell Roberts

Hawaii Intelligence Digest

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Neutrons provide the first nanoscale look at a living cell membrane

Neutrons provide the first nanoscale look at a living cell membrane | Amazing Science | Scoop.it

A research team from the Department of Energy's Oak Ridge National Laboratory has performed the first-ever direct nanoscale examination of a living cell membrane. In doing so, it also resolved a long-standing debate by identifying tiny groupings of lipid molecules that are likely key to the cell's functioning.

studies of membranes and, potentially, other cell components. It could prove useful for future research on important interactions such as drug-membrane, biofuel-membrane, and even antibiotic-membrane interactions.

 

The multidisciplinary project—led by biophysicist John Katsaras, chemist Bob Standaert and microbiologist James Elkins—was performed at the lab's High Flux Isotope Reactor and Spallation Neutron Source using the bacterium Bacillus subtilis. The team published its findings in the journal PLoS Biology.

 

A cell's membrane is a thin bilayer of lipid molecules among which reside other biomolecules such as proteins. Researchers have been uncertain about whether membrane lipids sometimes organize into groups called domains, also known as "rafts," or if they are randomly distributed in the membrane. Organization of lipids in distinct domains within the cell membrane is thought to enable functions such as signaling between cells.

 

"It became a debate," Katsaras said. "Some people believed they exist, while others believed they didn't. There was a lot of circumstantial evidence that could support either side." The problem was that existing techniques were not capable of unequivocally resolving this question.

 

Neutron scattering analysis was key to the project's success. Lipid domains are too small to be seen by optical microscopes that use light to probe samples such as biological cells. However, neutrons have no such limitation and can be used to provide a nanoscale view of a cell. Moreover, unlike other nanoscale tools, neutrons can be used for examining a live cell without damaging it.


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Discovered: Fast-growing galaxies from early universe

Discovered: Fast-growing galaxies from early universe | Amazing Science | Scoop.it

A team of astronomers including Carnegie's Eduardo Bañados and led by Roberto Decarli of the Max Planck Institute for Astronomy has discovered a new kind of galaxy which, although extremely old--formed less than a billion years after the Big Bang--creates stars more than a hundred times faster than our own Milky Way.

Their findings are published by Nature.

 

The team's discovery could help solve a cosmic puzzle--a mysterious population of surprisingly massive galaxies from when the universe was only about 10 percent of its current age.

 

After first observing these galaxies a few years ago, astronomers proposed that they must have been created from hyper-productive precursor galaxies, which is the only way so many stars could have formed so quickly. But astronomers had never seen anything that fit the bill for these precursors until now.

 

This newly discovered population could solve the mystery of how these extremely large galaxies came to have hundreds of billions of stars in them when they formed only 1.5 billion years after the Big Bang, requiring very rapid star formation.

 

The team made this discovery by accident when investigating quasars, which are supermassive black holes that sit at the center of enormous galaxies, accreting matter. They were trying to study star formation in the galaxies that host these quasars. "But what we found, in four separate cases, were neighboring galaxies that were forming stars at a furious pace, producing a hundred solar masses' worth of new stars per year," Decarli explained.

 

"Very likely it is not a coincidence to find these productive galaxies close to bright quasars. Quasars are thought to form in regions of the universe where the large-scale density of matter is much higher than average. Those same conditions should also be conducive to galaxies forming new stars at a greatly increased rate," added Fabian Walter, also of Max Planck.


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Research increases distance at which supernovas could spark mass extinctions on Earth

Research increases distance at which supernovas could spark mass extinctions on Earth | Amazing Science | Scoop.it

In 2016, researchers published “slam dunk” evidence, based on iron-60 isotopes in ancient seabed, that supernovae buffeted the Earth — one of them about 2.6 million years ago. University of Kansas researcher Adrian Melott, professor of physics and astronomy, supported those findings in Nature with an associated letter, titled “Supernovae in the neighborhood.”

 

Melott has followed up since those findings with an examination of the effects of the supernovae on Earth’s biology. In new research to appear in Astrophysical Journal, the KU researcher and colleagues argue the estimated distance of the supernova thought to have occurred roughly 2.6 million years ago should be cut in half.  

 

“There’s even more evidence of that supernova now,” he said. “The timing estimates are still not exact, but the thing that changed to cause us to write this paper is the distance. We did this computation because other people did work that made a revised distance estimate, which cut the distance in half. But now, our distance estimate is more like 150 light years.” A supernova exploding at such a range probably wouldn’t touch off mass extinctions on Earth, Melott said.  

 

“People estimated the ‘kill zone’ for a supernova in a paper in 2003, and they came up with about 25 light years from Earth,” he said. “Now we think maybe it’s a bit greater than that. They left some effects out or didn’t have good numbers, so now we think it may be a bit larger distance. We don’t know precisely, and of course it wouldn’t be a hard-cutoff distance. It would be a gradual change. But we think something more like 40 or 50 light years. So, an event at 150 light years should have some effects here but not set off a mass extinction.”

 

In addition to its distance, interstellar conditions at the time of a supernova would influence its lethality to biology on Earth. “Cosmic rays like to travel along magnetic field lines,” Melott said. “They don’t like to cut across magnetic field lines as they experience forces to stop them from doing that. If there’s a magnetic field, we don’t know its orientation, so it can either create a superhighway for cosmic ray, or it could block them.

 

The main interesting case did not assume the superhighway. It assumed that much of the magnetic field was blasted out by a series of supernovae, which made the Local Bubble — and we and the most recent supernovae were inside. This is a weak, disordered magnetic field. The best analogy I can think of is more like off-road driving.” In such a case, the authors think cosmic rays from the supernova at 150 light years would have penetrated to Earth’s lower atmosphere. 

 

“This is a much stronger thing,” he said. “The cosmic rays from the supernova would be getting down into the lower atmosphere — having an effect on the troposphere. All kinds of elementary particles are penetrating from altitudes of 45-10 miles, and many muons get to the ground. The effect of the muons is greater — it’s not overwhelming, but imagine every organism on Earth gets the equivalent of several CT scans per year. CT scans have some danger associated with them. Your doctor wouldn’t recommend a CT scan unless you really needed it.” 

 

Melott said cancer and mutations would be the most obvious consequences for Earth’s biology of a supernova’s cosmic rays. With his co-authors —  B.C. Thomas of Washburn University (2005 KU physics doctoral graduate and recent winner of the A. Roy Myers Excellence in Research Award), M. Kachelrieß of Institutt for fysikk in Norway, D.V. Semikoz of the Observatoire de Paris, Sorbonne Paris Cite in France and the National Research Nuclear University in Moscow, and A.C. Overholt (2013 KU physics doctoral graduate) of MidAmerica Nazarene University — Melott looked at the fossil record in Africa, the most geographically stable continent on earth during the Pleistocene, when a  supernova was likely to have occurred.

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A Whole New Jupiter: Newest Results from NASA’s Juno Mission

A Whole New Jupiter: Newest Results from NASA’s Juno Mission | Amazing Science | Scoop.it
Early science results from NASA’s Juno mission to Jupiter portray the largest planet in our solar system as a complex, gigantic, turbulent world, with Earth-sized polar cyclones, plunging storm systems that travel deep into the heart of the gas giant, and a mammoth, lumpy magnetic field that may indicate it was generated closer to the planet’s surface than previously thought.

“We are excited to share these early discoveries, which help us better understand what makes Jupiter so fascinating,” said Diane Brown, Juno program executive at NASA Headquarters in Washington. "It was a long trip to get to Jupiter, but these first results already demonstrate it was well worth the journey.”

Juno launched on Aug. 5, 2011, entering Jupiter’s orbit on July 4, 2016. The findings from the first data-collection pass, which flew within about 2,600 miles (4,200 kilometers) of Jupiter's swirling cloud tops on Aug. 27, are being published this week in two papers in the journal Science, as well as 44 papers in Geophysical Research Letters.

“We knew, going in, that Jupiter would throw us some curves,” said Scott Bolton, Juno principal investigator from the Southwest Research Institute in San Antonio. “But now that we are here we are finding that Jupiter can throw the heat, as well as knuckleballs and sliders. There is so much going on here that we didn’t expect that we have had to take a step back and begin to rethink of this as a whole new Jupiter.”

Among the findings that challenge assumptions are those provided by Juno’s imager, JunoCam. The images show both of Jupiter's poles are covered in Earth-sized swirling storms that are densely clustered and rubbing together.

“We're puzzled as to how they could be formed, how stable the configuration is, and why Jupiter’s north pole doesn't look like the south pole,” said Bolton. “We're questioning whether this is a dynamic system, and are we seeing just one stage, and over the next year, we're going to watch it disappear, or is this a stable configuration and these storms are circulating around one another?”

Another surprise comes from Juno’s Microwave Radiometer (MWR), which samples the thermal microwave radiation from Jupiter’s atmosphere, from the top of the ammonia clouds to deep within its atmosphere. The MWR data indicates that Jupiter’s iconic belts and zones are mysterious, with the belt near the equator penetrating all the way down, while the belts and zones at other latitudes seem to evolve to other structures. The data suggest the ammonia is quite variable and continues to increase as far down as we can see with MWR, which is a few hundred miles or kilometers. 

Prior to the Juno mission, it was known that Jupiter had the most intense magnetic field in the solar system. Measurements of the massive planet’s magnetosphere, from Juno’s magnetometer investigation (MAG), indicate that Jupiter’s magnetic field is even stronger than models expected, and more irregular in shape. MAG data indicates the magnetic field greatly exceeded expectations at 7.766 Gauss, about 10 times stronger than the strongest magnetic field found on Earth.

“Juno is giving us a view of the magnetic field close to Jupiter that we’ve never had before,” said Jack Connerney, Juno deputy principal investigator and the lead for the mission’s magnetic field investigation at NASA's Goddard Space Flight Center in Greenbelt, Maryland. “Already we see that the magnetic field looks lumpy: it is stronger in some places and weaker in others. This uneven distribution suggests that the field might be generated by dynamo action closer to the surface, above the layer of metallic hydrogen. Every flyby we execute gets us closer to determining where and how Jupiter’s dynamo works.”
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The World's Most Sensitive Dark Matter Detector Is Now Up and Running

The World's Most Sensitive Dark Matter Detector Is Now Up and Running | Amazing Science | Scoop.it
After three years of construction, the world's most sensitive dark matter experiment is online, and scientists report that the detector is operating as designed.

 

The XENON1T experiment is located deep beneath a mountain at the Gran Sasso National Laboratory in Italy (known by its Italian acronym, LNGS) so it can be shielded from interference caused by cosmic rays and other radiation sources on Earth's surface.

 

XENON1T is looking for the microscopic fireworks created byweakly interacting massive particles (WIMPs) crashing into xenon atoms. WIMPs are hypothetical particles that many scientists think are a primary component of dark matter.

Astronomical observations have confirmed that only about 15 percent of the material universe is composed of "ordinary" (or "baryonic") matter; nearly 85 percent is mysterious dark matter, which cannot be observed directly by telescopes. But dark matter's gravity can be measured indirectly via its effects on galaxy clusters and the rotation rates of galaxies, so we know it's out there.

 

Because WIMPs are so "weakly interacting" — that is, they cannot interact with normal matter via the electromagnetic, strong or weak forces — XENON1T can detect them only by looking out for lucky collisions between WIMPs and atoms in a chamber filled with pure liquid xenon cooled to minus 139 degrees Fahrenheit (minus 95 degrees Celsius).

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Unveiling the Quantum Necklace

Unveiling the Quantum Necklace | Amazing Science | Scoop.it
Researchers simulate quantum necklace-like structures in superfluids.

 

The quantum world is both elegant and mysterious. It is a sphere of existence where the laws of physics experienced in everyday life are broken—particles can exist in two places at once, they can react to each other over vast distances, and they themselves seem confused over whether they are particles or waves. For those not involved in the field, this world may seem trifling, but recently, researchers from the Okinawa Institute of Science and Technology Graduate University (OIST) have theoretically described two quantum states that are extraordinary in both the physics that define them and their visual appeal: a complex quantum system that simulates classical physics and a spellbinding necklace-like state. Their study is published in the journal Physical Review A.

 

The quest for these states begins with a doughnut, or rather, a doughnut-shaped container housing a rotating superfluid. This superfluid, which is a fluid that moves with no friction, is made of Bose-Einstein condensates (BECs) comprising particles with no charge that are cooled to near-zero degrees kelvin, a temperature so cold, that it does not exist in the universe outside of laboratories. At this temperature, particles begin to exhibit strange properties—they clump together, and eventually become indistinguishable from one another. In effect, they become a single entity and thus move as one.

 

Since this whirling BEC superfluid is operating at a quantum scale, where tiny distances and low temperatures reign, the physical characteristics of its rotation are not those seen in the classical world. Consider a father who is swinging his daughter around in a circle by the arms. Classical physics mandates that the child’s legs will move faster than her hands around the circle, since her legs must travel further to make a complete turn.

 

In the world of quantum physics the relationship is the opposite. “In a superfluid…things which are very far away [from the center] move really slowly, whereas things [that] are close to the center move very fast,” explains OIST Professor Thomas Busch, one of theresearchers involved in the study. This is what is happening in the superfluid doughnut.

 

In addition, the superfluid inside of the doughnut shows a uniform density profile, meaning that it is distributed around the doughnut evenly. This would be the same for most liquids that are rotating via classical or quantum rules. But what happens if another type of BEC is added, one that is made from a different atomic species and that cannot mix with the original BEC? Like oil and water, the two components will separate in a way that minimizes the area in which they are touching and form two semicircles on opposite sides of the doughnut container.

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Biggest ever simulations help to uncover the history of the galaxy

Biggest ever simulations help to uncover the history of the galaxy | Amazing Science | Scoop.it
The Royal Astronomical Society, encourages and promotes the study of astronomy, solar-system science, geophysics and closely related branches of science. The RAS organizes scientific meetings in Burlington House, its London HQ, and throughout the country, publishes international research and review journals, recognizes outstanding achievements by the award of medals and prizes, maintains an extensive library, supports education through grants and outreach activities and represents UK astronomy nationally and internationally.

 

Thousands of processors, terabytes of data, and months of computing time have helped a group of researchers in Germany create some of the largest and highest resolution simulations ever made of galaxies like our Milky Way. Led by Dr Robert Grand of the Heidelberger Institut fuer Theoretische Studien, the work of the Auriga Project appears in the journal Monthly Notices of the Royal Astronomical Society.

 

A composite of images from the simulation. (Left) Projected gas density of the galaxy environment about 10 billion years ago. Depicted are filamentary gas structures that feed the main galaxy at the centre. (Middle) Bird’s eye view of the gas disc in the present day. The fine detailed spiral pattern is clearly visible. (Right) Side-on view of the same gas disc in the present day. Cold gas is shown as blue, warm gas as green and hot gas as red.

 

Astronomers study our own and other galaxies with telescopes and simulations, in an effort to piece together their structure and history. Spiral galaxies like the Milky Way are thought to contain several hundred thousand million stars, as well as copious amounts of gas and dust. The spiral shape is commonplace, with a massive black hole at the centre, surrounded by a bulge of old stars, and arms winding outwards where relatively young stars like the Sun are found. However understanding how systems like our galaxy came into being continues to remain a key question in the history of the cosmos.

 

The enormous range of scales (stars, the building blocks of galaxies, are each about one trillion times smaller in mass than the galaxy they make up), as well as the complex physics involved, presents a formidable challenge for any computer model. Using the Hornet and SuperMUC supercomputers in Germany and a state-of-the-art code, the team ran 30 simulations at high resolution, and 6 at very high resolution, for several months.

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Gynandromorphs: Half Male, Half Female Animals

Gynandromorphs: Half Male, Half Female Animals | Amazing Science | Scoop.it

As they often do after a rainstorm, butterflies had gathered around puddles on Pigeon Mountain in northwest Georgia. Nets in hand, James Adams and his friend Irving Finkelstein watched the insects lapping up salts and proteins dissolved in the muddy water, their folded wings yawning apart now and then. There were silvery-blue Celastrinas and Skippers the color of cinnamon and ash. Largest of all were the Tiger Swallowtails—pastel lemon males with black dagger-like stripes and midnight-dark females with a dusting of evening cerulean.

 

Suddenly a very odd creature flitted past Adams and Finkelstein—a swallowtail unlike any they had ever seen. Its left half was yellow; its right, black. It was as though someone had sliced up two different insects and seamlessly sewn them back together. Finkelstein yelped and took a swipe at the bizarre beauty, missing by quite a bit. Suppressing his excitement, lest it misguide his hand, Adams chased the butterfly a few steps, swung, and netted it. He could see immediately that he had caught a gynandromorph—an animal that was half-male and half-female.

 

Butterfly collectors love gynandromorphs for their rarity as much as their peculiarity. They are unpredictable hiccups in nature’s symphony of symmetry. The creatures tantalize scientists, too, because they offer a unique opportunity: the chance to study typically male and female genes and anatomy in the same body.

 

For hundreds of years, naturalists have been documenting gynandromorphs among insects, spiders, lobsters, and birds. More recently, researchers—aided by increasingly sophisticated laboratory tools—have overturned reigning theories of sexual development by studying such hybrids. As has proven true time and again throughout the history of science, the creatures that seem strangest—those that are too odd, too asymmetrical to fit neatly into our presupposed categories—teach us the most about how all living things work. It turns out, for example, that the standard explanation of how a bird becomes male or female is wrong. Scientists came to this realization not by investigating scores of typical birds, but rather by examining a few gynandromorphs. It all started with an odd zebra finch.

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A new AI algorithm summarizes text amazingly well

A new AI algorithm summarizes text amazingly well | Amazing Science | Scoop.it
Training software to accurately sum up information in documents could have great impact in many fields, such as medicine, law, and scientific research.

 

Who has time to read every article they see shared on Twitter or Facebook, or every document that’s relevant to their job? As information overload grows ever worse, computers may become our only hope for handling a growing deluge of documents. And it may become routine to rely on a machine to analyze and paraphrase articles, research papers, and other text for you.

 

An algorithm developed by researchers at Salesforce shows how computers may eventually take on the job of summarizing documents. It uses several machine-learning tricks to produce surprisingly coherent and accurate snippets of text from longer pieces. And while it isn’t yet as good as a person, it hints at how condensing text could eventually become automated.

 

The algorithm produced, for instance, the following summary of a recent New York Times article about Facebook trying to combat fake news ahead of the U.K.’s upcoming election:

  • Social network published a series of advertisements in newspapers in Britain on Monday.
  • It has removed tens of thousands of fake accounts in Britain.
  • It also said it would hire 3,000 more moderators, almost doubling the number of people worldwide who scan for inappropriate or offensive content.

 

The Salesforce algorithm is dramatically better than anything developed previously, according to a common software tool for measuring the accuracy of text summaries. “I don’t think I’ve ever seen such a large improvement in any [natural-language-processing] task,” says Richard Socher, chief scientist at Salesforce. Socher is a prominent name in machine learning and natural-language processing, and his startup, MetaMind, was acquired by Salesforce in 2016.

 

The software is still a long way from matching a human’s ability to capture the essence of document text, and other summaries it produces are sloppier and less coherent. Indeed, summarizing text perfectly would require genuine intelligence, including commonsense knowledge and a mastery of language.

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Nanofibers feel forces and hear sounds made by individual cells

Nanofibers feel forces and hear sounds made by individual cells | Amazing Science | Scoop.it

Engineers at the University of California San Diego have developed a miniature device that's sensitive enough to feel the forces generated by swimming bacteria and hear the beating of heart muscle cells. The device is a nano-sized optical fiber that's about 100 times thinner than a human hair. It can detect forces down to 160 femtonewtons—about ten trillion times smaller than a newton—when placed in a solution containing live Helicobacter pylori bacteria, which are swimming bacteria found in the gut. In cultures of beating heart muscle cells from mice, the nano fiber can detect sounds down to -30 decibels—a level that's one thousand times below the limit of the human ear. "This work could open up new doors to track small interactions and changes that couldn't be tracked before," said nanoengineering professor Donald Sirbuly at the UC San Diego Jacobs School of Engineering, who led the study.

 

Some applications, he envisions, include detecting the presence and activity of a single bacterium; monitoring bonds forming and breaking; sensing changes in a cell's mechanical behavior that might signal it becoming cancerous or being attacked by a virus; or a mini stethoscope to monitor cellular acoustics in vivo.

The work is published in Nature Photonics on May 15.

 

The optical fiber developed by Sirbuly and colleagues is at least 10 times more sensitive than the atomic force microscope (AFM), an instrument that can measure infinitesimally small forces generated by interacting molecules. And while AFMs are bulky devices, this optical fiber is only several hundred nanometers in diameter. "It's a mini AFM with the sensitivity of an optical tweezer," Sirbuly said.

 

The device is made from an extremely thin fiber of tin dioxide, coated with a thin layer of a polymer, called polyethylene glycol, and studded with gold nanoparticles. To use the device, researchers dip the nano optical fiber into a solution of cells, send a beam of light down the fiber and analyze the light signals it sends out. These signals, based on their intensity, indicate how much force or sound the fiber is picking up from the surrounding cells. "We're not just able to pick up these small forces and sounds, we can quantify them using this device. This is a new tool for high resolution nanomechanical probing," Sirbuly said.

 

Here's how the device works: as light travels down the optical fiber, it interacts strongly with the gold nanoparticles, which then scatter the light as signals that can be seen with a conventional microscope. These light signals show up at a particular intensity. But that intensity changes when the fiber is placed in a solution containing live cells. Forces and sound waves from the cells hit the gold nanoparticles, pushing them into the polymer layer that separates them from the fiber's surface. Pushing the nanoparticles closer to the fiber allows them to interact more strongly with the light coming down the fiber, thus increasing the intensity of the light signals. Researchers calibrated the device so they could match the signal intensities to different levels of force or sound.

 

The key to making this work is the fiber's polymer layer. It acts like a spring mattress that's sensitive enough to be compressed to different thicknesses by the faint forces and sound waves produced by the cells. And Sirbuly says the polymer layer can be tuned—if researchers want to measure larger forces, they can use a stiffer polymer coating; for increased sensitivity, they can use a softer polymer like a hydrogel.

 

Moving forward, researchers plan to use the nano fibers to measure bio-activity and the mechanical behavior of single cells. Future works also includes improving the fibers' "listening" capabilities to create ultra-sensitive biological stethoscopes, and tuning their acoustic response to develop new imaging techniques.


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Radar warns motorcycle pilots of nearby traffic before they even see the oncoming cars

Radar warns motorcycle pilots of nearby traffic before they even see the oncoming cars | Amazing Science | Scoop.it

Radar warns motorcyclists of nearby traffic before they see oncoming cars. Motorcyclists are 18 times more likely to be killed in a collision. This new technology is about to change that. The claim is that this new radar could prevent nearly one-third of all motorcycle accidents.

 

RADAR technology initially developed for use in driverless cars has been adapted for motorcycles. Vehicle-to-vehicle communications developer Cohda Wireless from South Australia has partnered with Bosch, Ducati and Autotalks on a “digital protective shield” that warns riders of nearby traffic before they see oncoming cars. Bosch is commercializing the technology in Ducati production bikes but the radar could also be retrofitted to any car or motorcycle.

 

Production of the technology is being driven by a proposed mandate from the United States Department of Transportation that would require all new vehicles to have vehicle-to-vehicle radars installed. Cohda Wireless Managing Director Paul Gray said the radar was the next step in safety from seatbelts and airbags. “Technologists have gone as far as they can in terms of minimizing harm during an accident and now it is about avoiding the accidents before they even happen,” he said.

 

“If a motorcyclist is riding down the street, it will be alerted when a car turning onto the same road creates an opportunity for an accident. This can also happen when the car moving onto the road is not visible to the rider. The radar will also alert drivers who are changing lanes if someone is in their blind spot, which is quite an issue for motorcyclists.”

 

Gray said the technology would eventually be in every autonomous car as well. Cohda commands about 60% of the vehicle-to-vehicle communication market. The system uses the public WLAN standard (ITS G5) as the basis for the exchange of data between motorcycles and cars.

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NASA invites scientists to submit ideas for successful Europa lander

NASA invites scientists to submit ideas for successful Europa lander | Amazing Science | Scoop.it

Now is the time to voice your opinions on the lander’s instruments. NASA recently informed the science community to prepare for a planned competition to select science instruments for a potential Europa lander. While a Europa lander mission is not yet approved by NASA, the agency's Planetary Science Division has funding in Fiscal Year 2017 to conduct the announcement of opportunity process. "The possibility of placing a lander on the surface of this intriguing icy moon, touching and exploring a world that might harbor life is at the heart of the Europa lander mission," said Thomas Zurbuchen, associate administrator of NASA's Science Mission Directorate in Washington. "We want the community to be prepared for this announcement of opportunity, because NASA recognizes the immense amount of work involved in preparing proposals for this potential future exploration."

 

The community announcement provides advance notice of NASA's plan to hold a competition for instrument investigations for a potential Europa lander mission. Proposed investigations will be evaluated and selected through a two-step competitive process to fund development of a variety of relevant instruments and then to ensure the instruments are compatible with the mission concept. Approximately 10 proposals may be selected to proceed into a competitive Phase A. The Phase A concept study will be limited to approximately 12 months with a $1.5 million budget per investigation. At the conclusion of these studies, NASA may select some of these concepts to complete Phase A and subsequent mission phases.

 

Investigations will be limited to those addressing the following science objectives, which are listed in order of decreasing priority:

  • Search for evidence of life on Europa
  • Assess the habitability of Europa via in situ techniques uniquely available to a lander mission
  • Characterize surface and subsurface properties at the scale of the lander

 

In early 2016, in response to a congressional directive, NASA's Planetary Science Division began a study to assess the science and engineering design of a future Europa lander mission. NASA routinely conducts such studies—known as Science Definition Team (SDT) reports—long before the start of any mission to gain an understanding of the challenges, feasibility and science value of the potential mission. The 21-member team began work almost one year ago. The agency briefed the community on the Europa Lander SDT study at recent town halls at the 2017 Lunar and Planetary Science Conference (LPSC) at The Woodlands, Texas, and the Astrobiology Science Conference (AbSciCon) in Mesa, Arizona.

 

The proposed Europa lander is separate from and would follow its predecessor—the Europa Clipper multiple flyby mission - which now is in preliminary design phase and planned for launch in the early 2020s. Arriving in the Jupiter system after a journey of several years, the spacecraft would orbit the planet about every two weeks, providing opportunities for 40 to 45 flybys in the prime mission. The Clipper spacecraft would image Europa's icy surface at high resolution, and investigate its composition and structure of its interior and icy shell.

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How radioactive decay could support extraterrestrial life, study shows

How radioactive decay could support extraterrestrial life, study shows | Amazing Science | Scoop.it

In the icy bodies around our solar system, radiation emitted from rocky cores could break up water molecules and support hydrogen-eating microbes. To address this cosmic possibility, a University of Texas at San Antonio (UTSA) and Southwest Research Institute (SwRI) team modeled a natural water-cracking process called radiolysis. They then applied the model to several worlds with known or suspected interior oceans, including Saturn’s moon Enceladus, Jupiter’s moon Europa, Pluto and its moon Charon, as well as the dwarf planet Ceres.  

 “The physical and chemical processes that follow radiolysis release molecular hydrogen (H2), which is a molecule of astrobiological interest,” said Alexis Bouquet, lead author of the study published in the May edition of Astrophysical Journal Letters.

 

Radioactive isotopes of elements such as uranium, potassium, and thorium are found in a class of rocky meteorites known as chondrites. The cores of the worlds studied by Bouquet and his co-authors are thought to have chondrite-like compositions. Ocean water permeating the porous rock of the core could be exposed to ionizing radiation and undergo radiolysis, producing molecular hydrogen and reactive oxygen compounds.

 

Bouquet, a student in the joint doctoral program between UTSA’s Department of Physics and Astronomy and SwRI’s Space Science and Engineering Division, explained that microbial communities sustained by H2 have been found in extreme environments on Earth. These include a groundwater sample found nearly 2 miles deep in a South African gold mine and at hydrothermal vents on the ocean floor. That raises interesting possibilities for the potential existence of analogous microbes at the water-rock interfaces of ocean worlds such as Enceladus or Europa.

 

“We know that these radioactive elements exist within icy bodies, but this is the first systematic look across the solar system to estimate radiolysis. The results suggest that there are many potential targets for exploration out there, and that’s exciting,” says co-author Dr. Danielle Wyrick, a principal scientist in SwRI’s Space Science and Engineering Division.

One frequently suggested source of molecular hydrogen on ocean worlds is serpentinization. This chemical reaction between rock and water occurs, for example, in hydrothermal vents on the ocean floor.

 

The key finding of the study is that radiolysis represents a potentially important additional source of molecular hydrogen. While hydrothermal activity can produce considerable quantities of hydrogen, in porous rocks often found under seafloors, radiolysis could produce copious amounts as well.

 

Radiolysis may also contribute to the potential habitability of ocean worlds in another way. In addition to molecular hydrogen, it produces oxygen compounds that can react with certain minerals in the core to create sulfates, a food source for some kinds of microorganisms.

 

“Radiolysis in an ocean world’s outer core could be fundamental in supporting life. Because mixtures of water and rock are everywhere in the outer solar system, this insight increases the odds of abundant habitable real estate out there,” Bouquet said.

 

Co-authors of the article, “Alternative Energy: Production of H2 by Radiolysis of Water in the Rocky Cores of Icy Bodies,” are SwRI’s Dr. Christopher R. Glein, Wyrick, and Dr. J. Hunter Waite, who also serves as a UTSA adjoint professor. 

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Methanol detected for first time around young star

Methanol detected for first time around young star | Amazing Science | Scoop.it
Methanol, a key building block for the complex organic compounds that comprise life, has been detected for the first time in the protoplanetary disk of a young, distant star. This finding could help scientists better understand the chemistry occurring during a planet's formation that could ultimately lead to the emergence of life.

Scientists made the methanol discovery around TW Hydrae, a star about 80 percent of our sun's mass and roughly 5 million to 10 million years old. It represents a younger version of what our solar system may have looked like during its formation more than 4 billion years ago. At about 170 light-years away, TW Hydrae has the closest protoplanetary disk to Earth.

The methanol appears to be located in a ring peaking 30 astronomical units from the star. (An astronomical unit, or AU, is the average distance between Earth and the sun, or about 93 million miles.)

This methanol gas likely came from methanol ice located slightly further away from the star. The scientists detailed their findings in the paper, "First detection of gas-phase methanol in a protoplanetary disk," published the journal Astrophysical Journal Letters.

"Methanol is an important molecule because it has been shown in laboratory ice experiments to be a feedstock of larger and more complex molecules," said study lead author Catherine Walsh, an astrochemist at the University of Leeds in England. "The successful detection of methanol in a protoplanetary disk provides compelling evidence that larger molecules are also present."

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World's thinnest nano-hologram paves path to a new 3-D world

World's thinnest nano-hologram paves path to a new 3-D world | Amazing Science | Scoop.it
Researchers pave way towards integration of 3-D holography into electronics like smart phones, computers and TVs, with development of nano-hologram 1,000 times thinner than a human hair.

 

An Australian-Chinese research team has created the world's thinnest hologram, paving the way towards the integration of 3D holography into everyday electronics like smart phones, computers and TVs.

 

Interactive 3D holograms are a staple of science fiction -- from Star Wars to Avatar -- but the challenge for scientists trying to turn them into reality is developing holograms that are thin enough to work with modern electronics.

 

Now a pioneering team led by RMIT University's Distinguished Professor Min Gu has designed a nano-hologram that is simple to make, can be seen without 3D goggles and is 1000 times thinner than a human hair.

 

"Conventional computer-generated holograms are too big for electronic devices but our ultrathin hologram overcomes those size barriers," Gu said. "Our nano-hologram is also fabricated using a simple and fast direct laser writing system, which makes our design suitable for large-scale uses and mass manufacture. "Integrating holography into everyday electronics would make screen size irrelevant -- a pop-up 3D hologram can display a wealth of data that doesn't neatly fit on a phone or watch.

 

"From medical diagnostics to education, data storage, defence and cyber security, 3D holography has the potential to transform a range of industries and this research brings that revolution one critical step closer." Conventional holograms modulate the phase of light to give the illusion of three-dimensional depth. But to generate enough phase shifts, those holograms need to be at the thickness of optical wavelengths.

 

The RMIT research team, working with the Beijing Institute of Technology (BIT), has broken this thickness limit with a 25 nanometre hologram based on a topological insulator material -- a novel quantum material that holds the low refractive index in the surface layer but the ultrahigh refractive index in the bulk. The topological insulator thin film acts as an intrinsic optical resonant cavity, which can enhance the phase shifts for holographic imaging.

 

Dr Zengyi Yue, who co-authored the paper with BIT's Gaolei Xue, said: "The next stage for this research will be developing a rigid thin film that could be laid onto an LCD screen to enable 3D holographic display. "This involves shrinking our nano-hologram's pixel size, making it at least 10 times smaller. "But beyond that, we are looking to create flexible and elastic thin films that could be used on a whole range of surfaces, opening up the horizons of holographic applications."

 

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How Google’s ‘smart reply’ is getting smarter

How Google’s ‘smart reply’ is getting smarter | Amazing Science | Scoop.it

Last week, Google reported that it is rolling out an enhanced version of its “smart reply” machine-learning email software to “over 1 billion Android and iOS users of Gmail” — quoting Google CEO Sundar Pichai. The new smart-reply version is now able to handle challenging sentences like “That interesting person at the cafe we like gave me a glance,” as Google research scientist Brian Strope and engineering director Ray Kurzweil noted in a Google Research blog post. But “given enough examples of language, a machine learning approach can discover many of these subtle distinctions,” they wrote.

 

So, how does it work? “The content of language is deeply hierarchical, reflected in the structure of language itself, going from letters to words to phrases to sentences to paragraphs to sections to chapters to books to authors to libraries, etc.,” they explained. So a hierarchical approach to learning “is well suited to the hierarchical nature of language.This approach seems to work well for suggesting possible responses to emails. A hierarchy of modules, each of which considers features that correspond to sequences at different temporal scales, similar to how we understand speech and language, is being used.

 

“With Smart Reply, Google is assuming users want to offload the burdensome task of communicating with one another to our more efficient counterparts,” says Wired writer Liz Stinson. “It’s not wrong. The company says the machine-generated replies already account for 12 percent of emails sent; expect that number to boom once everyone with the Gmail app can send one-tap responses.

 

“In the short term, that might mean more stilted conversations in your inbox. In the long term, the growing number of people who use these canned responses is only going to benefit Google, whose AI grows smarter with every email sent.”

 

Another challenge is that our emails, particularly from mobile devices, “tend to be riddled with idioms [such as urban lingo] that make no actual sense,” suggests Washington Post writer Hayley Tsukayama. “Things change depending on context: Something ‘wicked’ could be good or very bad, for example. Not to mention, sarcasm is a thing.

 

“Which is all to warn you that you may still get a wildly random and even potentially inappropriate suggestion — I once got an ‘Oh no!’ suggestion to a friend’s self-deprecating pregnancy announcement, for example. If the email only calls for a one- or two-sentence response, you’ll probably find Smart Reply useful. If it requires any nuance, though, it’s still best to use your own human judgment.”

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Hottest lavas that erupted in past 2.5 billion years revealed

Hottest lavas that erupted in past 2.5 billion years revealed | Amazing Science | Scoop.it
Deep portions of Earth's mantle might be as hot as it was more than 2.5 billion years ago, an international team of researchers has recently discovered.

 

An international team of researchers led by geoscientists with the Virginia Tech College of Science recently discovered that deep portions of Earth's mantle might be as hot as it was more than 2.5 billion years ago. The study, led by Esteban Gazel, an assistant professor with Virginia Tech's Department of Geosciences, and his doctoral student Jarek Trela of Deer Park, Illinois, is published in the latest issue of Nature Geoscience. The study brings new, unprecedented evidence on the thermal evolution of the deep Earth during the past 2.5 billion years, Gazel said.

 

The Archean Eon -- covering from 2.5 to 4 billion years ago -- is one of the most enigmatic times in the evolution of our planet, Gazel said. During this time period, the temperature of Earth's mantle -- the silicate region between the crust and the outer core -- was hotter than it is today, owing to a higher amount of radioactive heat produced from the decay of elements such as potassium, thorium, and uranium. Because Earth was hotter during this period, this interval of geologic time is marked by the widespread of occurrence of a unique rock known as komatiite.

 

"Komatiites are basically superhot versions of Hawaiian style lava flows," Gazel said. "You can imagine a Hawaiian lava flow, only komatiites were so hot that they glowed white instead of red, and they flowed on a planetary surface with very different atmospheric conditions, more similar to Venus than the planet we live on today." Earth essentially stopped producing abundant hot komatiites after the Archean era because the mantle has cooled during the past 4.5 billion years due to convective cooling and a decrease in radioactive heat production, Gazel said.

 

However, Gazel and a team made what they call an astonishing discovery while studying the chemistry of ancient Galapagos-related lava flows, preserved today in Central America: a suite of lavas that shows conditions of melting and crystallization similar to the mysterious Archean komatiites.

 

Gazel and collaborators studied a set of rocks from the 90 million-year-old Tortugal Suite in Costa Rica and found that they had magnesium concentrations as high as Archean komatiites, as well as textural evidence for extremely hot lava flow temperatures.

 

"Experimental studies tell us that that the magnesium concentration of basalts and komatiites is related to the initial temperature of the melt," Gazel said. "They higher the temperature, the higher the magnesium content of a basalt."


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Male Fish Borrows Egg to Clone Itself

Male Fish Borrows Egg to Clone Itself | Amazing Science | Scoop.it

A fish created by spontaneous androgenesis is the first known vertebrate to arise naturally by this asexual reproductive phenomenon.

 

Researchers in Portugal studying a rare type of hybrid fish in the Ocreza River have found an individual that is the exact genomic match to his father. While such androgenesis—the reproduction of a male with no female genetic component—occurs in some non-vertebrates and has been induced in vertebrates artificially, today’s report (May 24) in Royal Society Open Science is the first known description of a vertebrate reproducing this way in the wild.

 

“I was very surprised,” said Miguel Morgado-Santos, a graduate student at the University of Lisbon in Portugal who co-authored the study. “I thought maybe it was a mistake and we had captured the father.” But, when the researchers examined the animal’s mitochondrial DNA, which can only be inherited from the mother’s egg, they found that it differed from the father’s. “So, it was definitely an androgenetic individual,” he said. “Although [androgenesis] is very rare, there are a number of species out there that do this and . . . it is interesting that people have found it now in a vertebrate,” said evolutionary biologist Laura Ross of the University of Edinburgh who was not involved in the study.

 

While the females of many species, including some vertebrates, are well known to be able to reproduce themselves without any input from a male—a process called parthenogenesis—“for a long time, biologists thought that clonal reproduction by males was impossible as they are not able to have babies,” said Ross. However, there are now known to be a handful of species—certain types of ants and fresh water clams, for example—where the “males basically use a surrogate mum to clone themselves,” she said.

 

Because there are so few examples of androgenesis, it is not always clear how the phenomenon arises. However, in some species the males are thought to produce sperm with twice the normal genetic content (diploid), and the genetic content of the egg is either absent or eliminated after fertilization. Alternatively, it’s possible that a normal sperm (haploid) can fertilize an egg with either an absent or eliminated genome and the male genome then replicates, or that two sperm can co-fertilize a genome-less egg. Which, if any, of these occurred in the fish is unknown, said Morgado-Santos.

 

“In a lot of these cases,” Ross said, “these bizarre types of reproduction seem to have arisen by two closely related species hybridizing at some point in their evolutionary history and something going really, really wrong with reproduction.” Hybridization often results in unmatched chromosome numbers, and consequent sterility of the offspring, she explained, so in essence the reproductive quirks provide a workaround.

 

Indeed, the fish that is the subject of the new research—Squalius alburnoides—is the result of a natural hybridization event between another fish, Squalius pyrenaicus, and a now extinct species of the lineage Anaecypris hispanica.

 

Members of S. alburnoides are an assorted mix of diploids, triploids and tetrapoids, meaning they carry different combinations and copy numbers of the two genomes of the originator species, explained Morgado-Santos. He and colleagues had been studying an isolated population of S. alburnoides in the hopes of figuring out the complexities of reproduction in these strange fish when, by chance, they found a male offspring that was an exact genomic replica of its father.

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Digital logic circuits in yeast using CRISPR-dCas9 NOR gates

Digital logic circuits in yeast using CRISPR-dCas9 NOR gates | Amazing Science | Scoop.it

Natural genetic circuits enable cells to make sophisticated digital decisions. Building equally complex synthetic circuits in eukaryotes remains difficult, however, because commonly used components leak transcriptionally, do not arbitrarily interconnect or do not have digital responses. Scientists now designed dCas9-Mxi1-based NOR gates in Saccharomyces cerevisiae that allow arbitrary connectivity and large genetic circuits. Because they used the chromatin remodeller Mxi1, their gates showed minimal leak and digital responses. The researchers built a combinatorial library of NOR gates that directly convert guide RNA (gRNA) inputs into gRNA outputs, enabling the gates to be ‘wired’ together. They constructed logic circuits with up to seven gRNAs, including repression cascades with up to seven layers. Modeling predicted the NOR gates have effectively zero transcriptional leak explaining the limited signal degradation in the circuits. This approach enabled the largest, eukaryotic gene circuits to date and will form the basis for large, synthetic, cellular decision-making systems.

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Mining the moon for rocket fuel to get us to Mars

Mining the moon for rocket fuel to get us to Mars | Amazing Science | Scoop.it

Forty-five years have passed since humans last set foot on an extraterrestrial body. Now, the moon is back at the center of efforts not only to explore space, but to create a permanent, independent space-faring society.

 

Planning expeditions to Earth's nearest celestial neighbor is no longer just a NASA effort, though the U.S. space agency has plans for a moon-orbiting space station that would serve as a staging ground for Mars missions in the early 2030s. The United Launch Alliance, a joint venture between Lockheed Martin and Boeing, is planning a lunar fueling station for spacecraft, capable of supporting 1,000 people living in space within 30 years.

 

Billionaires Elon Musk, Jeff Bezos and Robert Bigelow all have companies aiming to deliver people or goods to the moon. Several teams competing for a share of Google's US$30 million cash prize are planning to launch rovers to the moon. Groups of students from around the world recently participated in the 2017 Caltech Space Challenge, proposing designs of what a lunar launch and supply station for deep space missions might look like, and how it would work.

 

Right now all space missions are based on, and launched from, Earth. But Earth's gravitational pull is strong. To get into orbit, a rocket has to be traveling 11 kilometers a second – 25,000 miles per hour!

 

Any rocket leaving Earth has to carry all the fuel it will ever use to get to its destination and, if needed, back again. That fuel is heavy – and getting it moving at such high speeds takes a lot of energy. If we could refuel in orbit, that launch energy could lift more people or cargo or scientific equipment into orbit. Then the spacecraft could refuel in space, where Earth's gravity is less powerful.

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Massive Lava Waves Detected on Jupiter’s Moon Io

Massive Lava Waves Detected on Jupiter’s Moon Io | Amazing Science | Scoop.it
Io is the closest thing we have to hell in our Solar System, a Jovian moon that features hundreds of active volcanoes and expansive lakes filled with lava. New observations suggests that the largest of these lakes, Loki Patera, produces enormous waves that repeatedly flow around the molten surface.

 

Jupiter's moon Io has the biggest active volcano in the Solar System. Inside the volcano, a warm floor surrounds a cool central island. Previous observations have indicated that volcanic resurfacing occurs every one to three years, but telescope observations have insufficient resolution to see how this progresses, and spacecraft observations have not been able to see the entire floor at once. Katherine De Kleer et al. used an occultation of Io by another of Jupiter's moons (Europa) to map the entire floor at a spatial resolution of 2 kilometers, using interferometric telescope observations. They find that the resurfacing happens in two waves, with different starting times and velocities, which then converge around the central island. They interpret the differences between the waves as evidence of either a non-uniformity in the lava or variations in the bulk density of the crust across the volcano.

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Scientists discover dolphins speech complexity is almost as high as in humans

Scientists discover dolphins speech complexity is almost as high as in humans | Amazing Science | Scoop.it

Dolphins are capable of “highly developed spoken language” which closely resembles human communication, scientists have suggested.  While it has long been acknowledged dolphins are of high intelligence and can communicate within a larger pack, their ability to converse with each other individually has been less understood.

 

But researchers at the Karadag Nature Reserve, Feodosia, Crimea, believe the pulses, clicks and whistles – of up to five “words” – made by dolphins are listened to fully by another before a response is made. 

 
 

“Essentially, this exchange resembles a conversation between two people,” wrote lead researcher Dr Vyacheslav Ryabov in the study,published in the journal Mathematics and Physics. Dr Ryabov said each pulse produced by a dolphin “is different from another” in its time span and the frequencies it emits. 

 

“In this regard, we can assume that each pulse represents a phoneme or a word of the dolphin’s spoken language,” Dr Ryabov wrote. However: “The dolphin’s speech unfortunately lies beyond the time and frequency characteristics of the human hearing, and is thus unavailable to humans.”


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Physicists find a way to control charged molecules -- with quantum logic

Physicists find a way to control charged molecules -- with quantum logic | Amazing Science | Scoop.it

National Institute of Standards and Technology (NIST) physicists have solved the seemingly intractable puzzle of how to control the quantum properties of individual charged molecules, or molecular ions. The solution is to use the same kind of "quantum logic" that drives an experimental NIST atomic clock. The new technique achieves an elusive goal, controlling molecules as effectively as laser cooling and other techniques can control atoms. Quantum control of atoms has revolutionized atomic physics, leading to applications such as atomic clocks. But laser cooling and control of molecules is extremely challenging because they are much more complex than atoms.

 

The NIST technique still uses a laser, but only to gently probe the molecule; its quantum state is detected indirectly. This type of control of molecular ions -- several atoms bound together and carrying an electrical charge -- could lead to more sophisticated architectures for quantum information processing, amplify signals in basic physics research such as measuring the "roundness" of the electron's shape, and boost control of chemical reactions.

 

The research is described in the May 11, 2017 issue of Nature and was performed in the NIST Boulder group that demonstrated the first laser cooling of atomic ions in 1978. "We developed methods that are applicable to many types of molecules," NIST physicist James Chinwen Chou said. "Whatever trick you can play with atomic ions is now within reach with molecular ions. Now the molecule will 'listen' to you -- asking, in effect, 'What do you want me to do?'"

 

"This is comparable to when scientists could first laser cool and trap atoms, opening the floodgates to applications in precision metrology and information processing. It's our dream to achieve all these things with molecules," Chou added. Compared to atoms, molecules are more difficult to control because they have more complex structures involving many electronic energy levels, vibrations and rotations. Molecules can consist of many different numbers and combinations of atoms and be as large as DNA strands more than a meter long.

 

The NIST method finds the quantum state (electronic, vibrational, and rotational) of the molecular ion by transferring the information to a second ion, in this case an atomic ion, which can be laser cooled and controlled with previously known techniques. Borrowing ideas from NIST's quantum logic clock, the researchers attempt to manipulate the molecular ion and, if successful, set off a synchronized motion in the pair of ions. The manipulation is chosen such that it can only trigger the motion if the molecule is in a certain state. The "yes" or "no" answer is signaled by the atomic ion. The technique is very gentle, indicating the molecule's quantum states without destroying them.

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