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IBM sets new speed record for Big Data

IBM sets new speed record for Big Data | Amazing Science | Scoop.it

IBM has announced it has achieved a new data-transmission advancement that will help improve Internet backbone speeds to 200 — 400 gigabits per second (Gb/s) at extremely low power. The speed boost is based on a new lab prototype chip design that can be used to improve transfer of Big Data between clouds and data centers via fiber four times faster than current 100 Gb/s technology. A previous version of the technology has been licensed to Semtech Corp., a leading supplier of analog and mixed-signal semiconductors. Semtech is using that technology to develop advanced communications platforms expected to be announced later this year, ranging from optical and wireline communications to advanced radar systems.


As Big Data and Internet data traffic continue to grow exponentially, future networking standards have to support higher data rates. For example, in 1992, 100 gigabytes of data was transferred per day; today, traffic has grown to two exabytes per day, a 20-million-fold increase. To support the increase in traffic, scientists at IBM Research and Ecole Polytechnique Fédérale de Lausanne (EPFL) have been developing ultra-fast, energy-efficient, analog-to-digital converter (ADC) technology to enable transmission across long-distance fiber channels.


For example, scientists plan to use ADCs to convert the analog radio signals that originate from the cosmos to digital. It’s part of a collaboration called DOME between ASTRON, the Netherlands Institute for Radio Astronomy, DOME-South Africa, and IBM to develop a fundamental IT roadmap for the Square Kilometer Array (SKA), an international project to build the world’s largest and most sensitive radio telescope.


The analog radio data that the SKA collects from deep space is expected to produce multiple petabits (1015 bits) per second — 10 times the current global Internet traffic. IBM says the prototype ADC would be an ideal candidate to transport the signals fast and at very low power — a critical requirement considering the ~3,000 radio telescopes, each transmitting ~160 Gb/s, that will be spread over a square kilometer.


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Two Worlds, One Sun: Blue Sunsets on Mars

Two Worlds, One Sun: Blue Sunsets on Mars | Amazing Science | Scoop.it
While Earth can have lovely red sunsets, Mars can have a sunset that is truly blue.

 

Earth has a relatively thick atmosphere, so most of the atmospheric scattering occurs when light strikes a molecule of air, known as Rayleigh scattering. Rayleigh scattering occurs when the object a photon scatters off (the air molecule) is much smaller than the wavelength of the photon. The closer the wavelength is to the size of the molecule, the more likely it is to scatter. This means that red wavelengths (which are the longer wavelengths of visible light) don’t scatter with air molecules much, while blue wavelengths (which are shorter) tend to scatter a lot. In fact blue light is almost 10 times more likely to scatter against air molecules than red light. This is why the sky appears blue, since so much of the blue light is scattered.

 

When the Sun is low in the sky, it’s light has to travel a long path through the atmosphere to reach you. As the light travels through the atmosphere some of the photons are scattered off the air molecules. When the photons scatter off air molecules, they scatter randomly in all directions, so usually when a photon scatters, it scatters away from your line of sight. Since blue photons scatter much more often than red ones, much of the blue light is scattered away. This leaves red photons to reach your eye. Hence the Sun looks red when low in the sky. When the Sun is overhead, the path it takes to reach you is much shorter, so only a bit of the blue light is scattered. So the Sun looks yellow.

 

Mars has a much thinner atmosphere, so the amount of Rayleigh scattering is much less. But Mars also has a dry, dusty surface, and a weaker surface gravity, so the atmosphere of Mars is often filled with fine dust particles. These particles are more comparable in size to the wavelengths of visible light, so most of the light is scattered by Mie scattering. One of the main differences between Rayleigh and Mie scattering is that Rayleigh scattering tends to occur in all directions, but Mie scattering varies with scattering angle. What this means is that longer wavelengths (reds) tend to scatter more uniformly, while shorter wavelengths (blues) tend to scatter at slight angles. This means that blue light tends to be deflected less than red light. This means Mars can have a dusty red daytime sky, and a blue sunset.

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Scientists discover how supermassive black holes keep galaxies turned off

Scientists discover how supermassive black holes keep galaxies turned off | Amazing Science | Scoop.it
An international team of scientists has identified a common phenomenon in galaxies that could explain why huge numbers of them turn into cosmic graveyards.

 

Galaxies begin their existence as lively and colourful spiral galaxies, full of gas and dust, and actively forming bright new stars. However, as galaxies evolve, they quench their star formation and turn into featureless deserts, devoid of fresh new stars, and generally remain as such for the rest of their evolution. But the mechanism that produces this dramatic transformation and keeps galaxies turned off, is one of the biggest unsolved mysteries in galaxy evolution.

 

Now, thanks to the new large SDSS-IV MaNGA survey of galaxies, a collaborative effort led by the University of Tokyo and involving the University of Oxford has discovered a surprisingly common new phenomenon in galaxies, dubbed "red geysers", that could explain how the process works.

 

Researchers interpret the red geysers as galaxies hosting low-energy supermassive black holes which drive intense interstellar winds. These winds suppress star formation by heating up the ambient gas found in galaxies and preventing it to cool and condense into stars.

 

The research will be published in the journal Nature. Lead author Dr Edmond Cheung, from the University of Tokyo's Kavli Institute for the Physics and Mathematics of the Universe, said: 'Stars form from the gas, but in many galaxies stars were found not to form despite an abundance of gas. It was like having deserts in densely clouded regions. We knew quiescent galaxies needed some way to suppress star formation, and now we think the red geysers phenomenon may represent how typical quiescent galaxies maintain their quiescence.'

 

'Stars form from the gas, a bit like the drops of rain condense from the water vapour. And in both cases one needs the gas to cool down, for condensation to occur. But we could not understand what was preventing this cooling from happening in many galaxies,' said Co-author Dr Michele Cappellari, from the Department of Physics at Oxford University. 'But when we modelled the motion of the gas in the red geysers, we found that the gas was being pushed away from the galaxy centre, and escaping the galaxy gravitational pull.'

 

'The discovery was made possible by the amazing power of the ongoing MaNGA galaxy survey' said Dr Kevin Bundy, from the University of Tokyo, the overall leader of the collaboration. 'The survey allows us to observe galaxies in three dimensions, by mapping not only how they appear on the sky, but also how their stars and gas move inside them.'

 

Using a near-dormant distant galaxy named Akira as a prototypical example, the researchers describe how the wind's driving mechanism is likely to originate in Akira's galactic nucleus. The energy input from this nucleus, powered by a supermassive black hole, is capable of producing the wind, which itself contains enough mechanical energy to heat ambient, cooler gas in the galaxy and thus suppress star formation.

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Mars Has Just Exited an Extreme Ice Age, Peaking 370,000 Years Ago

Mars Has Just Exited an Extreme Ice Age, Peaking 370,000 Years Ago | Amazing Science | Scoop.it
Just a few hundred thousand years ago, the Red Planet was hardly that.​

 

Had you searched the sky with a telescope just a few hundred thousand years ago, you would have struggled to find a red planet. Instead, you would have seen a gleaming-white ice ball where Mars should be. A team of astronomers led by Isaac Smith, an astrophysicist at the Southwest Research Institute in Boulder, Colorado, has collected the first concrete evidence that Mars has just exited an extreme ice age, one so intense it would have put Earth's recent frosty foray to shame. 

 

Using cameras and a radar-pinging device on board NASA's Mars Reconnaissance Orbiter, Smith's team deduced this history by dating the miles-deep layers of snow and ice packed onto the Red Planet's northern pole. They found that only a mere 370,000 years ago, "Mars would have actually looked more white than red," says Smith. The Mars research is outlined today in the journal Science

 

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Stem cell gene Oct4 helps to prevent heart attack, stroke, and counteracts aging

Stem cell gene Oct4 helps to prevent heart attack, stroke, and counteracts aging | Amazing Science | Scoop.it

University of Virginia School of Medicine have discovered that a gene called Oct4 — which scientific dogma insists is inactive in adults — actually plays a vital role in preventing ruptured atherosclerotic plaques inside blood vessels, the underlying cause of most heart attacks and strokes.

 

The researchers found that Oct4 controls the conversion of smooth muscle cells into protective fibrous “caps” inside plaques, making the plaques less likely to rupture. They also discovered that the gene promotes many changes in gene expression that are beneficial in stabilizing the plaques. In addition, the researchers believe it may be possible to develop drugs or other therapeutic agents that target the Oct4 pathway as a way to reduce the incidence of heart attacks or stroke.

 

The researchers are also currently testing Oct4′s possible role in repairing cellular damage and healing wounds, which would make it useful for regenerative medicine.

 

Oct4 is one of the “stem cell pluripotency factors” described by Shinya Yamanaka, PhD, of Kyoto University, for which he received the 2012 Nobel Prize. His lab and many others have shown that artificial over-expression of Oct4 within somatic cells grown in a lab dish is essential for reprogramming these cells into induced pluripotential stem cells, which can then develop into any cell type in the body or even an entire organism.

 

“Finding a way to reactivate this pathway may have profound implications for health and aging,” said researcher Gary K. Owens, director of UVA’s Robert M. Berne Cardiovascular Research Center. “This could impact many human diseases and the field of regenerative medicine. [It may also] end up being the ‘fountain-of-youth gene,’ a way to revitalize old and worn-out cells.”

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Gene editing creates hornless cattle

Gene editing creates hornless cattle | Amazing Science | Scoop.it
Alison L. Van Eenennaam, PhD, a geneticist and cooperative extension specialist also at UC-Davis, is working with the Minnesota-based company Recombinetics on, among other things, a project that has produced some of the Holstein dairy cattle that lack horns by editing one allele to match another found in Angus cattle.

“We’ve still got a dairy cow with all the good dairy genetics,” she said. “We’ve just gone in and tweaked a little snippet of DNA at the gene that makes horns and made it so it’s the variant for Angus, which doesn’t grow horns.”
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Magnetic Reconnection Directly Observed for First Time

Magnetic Reconnection Directly Observed for First Time | Amazing Science | Scoop.it

The effects of this sudden release of particles and energy have been observed throughout the solar system and beyond.

 

In a first, the US space agency has directly observed fundamental process of nature after sending four spacecraft through an invisible whirlpool in space called magnetic reconnection, like sending sensors up into a hurricane. The findings showed that magnetic reconnection is dominated by the physics of electrons - thus providing crucial information about what powers this fundamental process in nature.

 

Magnetic reconnection is one of the prime drivers of space radiation and a key factor in the quest to learn more about our space environment and protect our spacecraft and astronauts. The effects of this sudden release of particles and energy - such as giant eruptions on the sun or radiation storms in near-Earth space - have been observed throughout the solar system and beyond.

 

"We developed a mission called the Magnetospheric Multiscale mission (MMS) that for the first time would have the precision needed to gather observations in the heart of magnetic reconnection," said Jim Burch, principal investigator at the Southwest Research Institute in San Antonio, Texas.

 

"We received results faster than we could have expected. By seeing magnetic reconnection in action, we have observed one of the fundamental forces of nature," he added. MMS is made of four identical spacecraft that were launched in March 2015. They fly in a pyramid formation to create a full 3D map of any phenomena they observe.

 

On October 16, 2015, the spacecraft travelled straight through a magnetic reconnection event at the boundary where Earth's magnetic field bumps up against the sun's magnetic field.

 

In only a few seconds, the 25 sensors on each of the spacecraft collected thousands of observations. By watching these electrons, MMS made the first observation of the predicted breaking and interconnection of magnetic fields in space.

 

"The data showed the entire process of magnetic reconnection to be fairly orderly and elegant," said Michael Hesse, space scientist at Goddard, in a paper published in the journal Science. There does not seem to be much turbulence present, or at least not enough to disrupt or complicate the process.

 

This suggests that it is the physics of electrons that is at the heart of understanding how magnetic field lines accelerate the particles.

 

Since its launch, MMS has made more than 4,000 trips through the magnetic boundaries around Earth, each time gathering information about the way the magnetic fields and particles move.


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Nanomotors swiftly silence genes

Nanomotors swiftly silence genes | Amazing Science | Scoop.it

The promise of short interfering RNA (siRNA) is that it can be harnessed to turn off harmful genes in the cell. The difficulty is getting siRNA into the cell in the first place. In a new approach, nanoengineers have driven siRNA into the cell on acoustically-propelled nanomotors, silencing genes faster and more completely than with current methods (ACS Nano2016, DOI: 10.1021/acsnano.6b01415).

 

To silence a gene, researchers tap the cell’s own gene suppression system, which quashes the RNA messengers that are produced when a DNA sequence is expressed. The messengers are knocked out by siRNA, complementary to a given messenger RNA, which binds the mRNA and prevents it from being translated into a protein. Scientists can mooch off the cell’s gene suppression infrastructure simply by inserting an engineered siRNA specific to a target into the cell.

 

But that’s easier said than done. The negatively charged siRNA has to cross a negatively-charged cell membrane, traverse the intracellular milieu, and bump into the cell’s silencing complex before degradation enzymes destroy it.

 

The delivery challenge has spawned a bounty of possible siRNA carriers: metal particles, lipid bubbles, hydrogels, and more. Most of these strategies rely on some form of chemical camouflage to enter the cell and on diffusion to do the rest. But Yi Chen and Joseph Wang of the University of California, San Diego, thought that ultrasound-propelled nanowires might produce an siRNA transporter with more oomph.

 

When bombarded with ultrasound, these tiny gold rods—about 4 μm long, 200 nm in diameter, and concave at one end—scurry into motion. They penetrate cells, bounce around like pinballs, and even spin.


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Physicists discover new form of light, validate decades-old quantum mechanics prediction

Physicists discover new form of light, validate decades-old quantum mechanics prediction | Amazing Science | Scoop.it

It’s been over 340 years since Danish physicist Ole Rømer observed that the speed of light was finite. And, to this day, photons still manage to surprise us. Last year, scientists revealed a new fundamental property of light. This year, a team of physicists from by the Trinity College Dublin and the CRANN Institute have just discovered a new form of light that refuses to behave normally, and undermines what physicists know about angular momentum.

 

“Angular momentum measures how much something is rotating,” one of the study’s researchers, Kyle Ballantine, told Trinity News. “For a beam of light, although traveling in a straight line it can also be rotating around its own axis.” Up until this finding, physicists thought the angular momentum of all forms of light was a multiple of Planck’s constant. Apparently, that’s not so.

 

To uncover this information, the researchers began by searching for new behaviors of light by shining beams through crystals to create “screw-like structures.” They used the theory of quantum mechanics to analyze these beam structures and realized that the angular momentum of the photon would be a half-integer, not a multiple of Planck’s constant.

 

This discovery might not sound like much, but researchers suggest that it will influence our knowledge about the very essence of light. “Our discovery will have real impacts for the study of light waves in areas such as secure optical communications,” Professor John Donegan said.

 

Finding a new form of light is undoubtedly exciting. However, much of the physics community’s real joy comes from validating 30-year-old theoretical physics predictions. In the 1980s, physicists speculated ways in which quantum mechanics would open doors for strange new discoveries, such as particles with fractions of their expected quantum numbers. This research provides the first validation of those predictions. “This discovery is a breakthrough for the world of physics and science alike,” said CRANN Director, Stefano Santo.

 


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How Earth’s magnetic field is changing

How Earth’s magnetic field is changing | Amazing Science | Scoop.it

Earth’s continuously changing magnetic field is thought to be largely generated by superheated, swirling liquid iron in Earth’s outer core. Other sources of earthly magnetism include minerals in our world’s mantle and crust.

 

Earth’s ionosphere, magnetosphere and oceans also play a role. The European Space Agency (ESA) now has two years of data from a trio of satellites in Earth-orbit, designed to measure magnetism from these various sources. The mission is called Swarm. At last week’s Living Planet Symposium held in Prague in the Czech Republic (May 9-13, 2016), scientists presented new results from the Swarm satellite trio and provided some recent insights about how Earth’s magnetic field is changing at this time.

 

Among other things, they said that the field has weakened by about 3.5% at high latitudes over North America, while it has grown about 2% stronger over Asia. The region where the field is at its weakest field – the South Atlantic Anomaly – has moved steadily westward and further weakened by about 2%.

 

Meanwhile, the magnetic north pole has been wandering east, towards Asia. The animation shown in this article is based partly on results from ESA’s Swarm mission, and partly on information from the CHAMP and Ørsted satellites. It shows how the strength of Earth’s magnetic field changed between 1999 and mid-2016. Blue depicts where the field is weak and red shows regions where the field is strong. As you can see, the changes in field strength are relatively small.


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Scientists Unveil A Novel Genome Editing Technique Similar To CRISPR-CAS

Scientists Unveil A Novel Genome Editing Technique Similar To CRISPR-CAS | Amazing Science | Scoop.it

The CRISPR/Cas9 system is currently the technique in genome editing. Thanks to recent developments in the CRISPR genome editing system, we are able to alter DNA with unprecedented precision and accuracy. Ultimately, this revolutionary genome editing technique allows us to modify any region of the genome of any species—without harming other genes. But more than that, we are able to edit these genes at just a fraction of the cost of previous methods.

 

It has utterly revolutionized gene editing. However, a team of researchers has just developed a new approach that just might prove to be as efficient and effective as the current standard.

In a study published in Nature Biotechnology, researchers from Chunyu Han’s lab have developed a novel genome editing technique basically just like CRISPR.

 

According to the report, the method is based on the Natronobacterium gregoryi Argonaute (NgAgo), a DNA-guided endonuclease that’s similar to Cas9, the endonuclease of CRISPR. These are a specific type of protein, otherwise known as restriction enzymes, that are responsible for cutting DNA at specific locations. Remarkably, the study shows that NgAgo is suitable for genome editing in human cells.

 

The team asserts that their study has a number of key differences between NgAgo and Cas9, where the former is at the advantage. They claim that that the method appears to have a low tolerance to guide-target mismatches, leading to a high efficiency in editing:

 

  • One of these is that NgAgo does not need to be followed by a protospacer-adjacent motif (PAM), a DNA sequence seen in Cas9. Notably, Cas9 will not successfully bind or cleave a target DNA sequence if this is not followed by the PAM (as it is responsible for the protein to differentiate CRISPR DNA from target DNA).
  • Another benefit is that the loading temperature of NgAgo is found to be at 55°C and not at Cas9’s 37°C. This shows that this could be another option for genome editing at conditions such as this. Also, at this temperature, the method follows a “one-guide-faithful” rule, that is, NgAgo cannot swap target DNA with other free DNA, minimizing off-target effects.

 

Though there has yet to be an extensive side-by-side comparison of the two enzymes, NgAgo and Cas9 appear to have similar efficiencies. The authors report that their tests with 47 guides targeting 8 human genes, the results showed a 21% to 41% efficiency.

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The race to create super-crops

The race to create super-crops | Amazing Science | Scoop.it
Old-fashioned breeding techniques are bearing more fruit than genetic engineering in developing hyper-efficient plants.

 

Big corporations such as DuPont Pioneer in Johnston, Iowa, have spent more than a decadedeveloping improved crops through genetic engineering, and some companies say that their transgenic varieties look promising in field trials. But there are still no fertilizer-frugal transgenic crops on the market, and several agricultural organizations around the globe are reviewing their biotechnology initiatives in this area.

 

Plant biologist Allen Good of the University of Alberta in Edmonton, Canada, spent years working with companies to develop genetically modified (GM) crops that require little fertilizer, but he says that this approach has not been as fruitful as conventional techniques. The problem is that there are so many genes involved in nutrient uptake and use — and environmental variations alter how they are expressed.

 

“Nutrient efficiency was supposed to be one of those traits with broad applicability that could make companies lots of money. But they haven't developed the way we thought,” says Good.

 

Despite the scientific and breeding challenges, some researchers say that all strategies must be explored to develop crops that are less nutrient needy. With the global population heading towards 10 billion people by 2050, frugal crops could be essential to feed the planet. “There is a huge worldwide potential for these traits to help increase food production and sustainable development,” says Matin Qaim, an agricultural economist at the University of Göttingen in Germany.


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Physicists Suggest Link Between Dark Energy and the Arrow of Time

Physicists Suggest Link Between Dark Energy and the Arrow of Time | Amazing Science | Scoop.it

Is dark energy the reason time moves forward? For years, physicists have attempted to explain dark energy - a mysterious influence that pushes space apart faster than gravity can pull the things in it together. But physics isn’t always about figuring out what things are. A lot of it is figuring out what things cause. In a recent paper, a group of physicists asked this very question about dark energy, and found that in some cases, it might cause time to go forward.

When you throw a ball into the air, it starts with some initial speed-up, but then it slows as Earth’s gravity pulls it down. If you throw it fast enough (about 11 km per second, for those who want to try), it’ll never slow down enough to turn around and start falling back towards you, but it’ll still move more slowly as it moves away from you, because of Earth’s gravity.

Physicists and astronomers in the 1990s expected something similar to have occurred after the big bang - an event that threw matter out in all directions. The collective gravity from all that matter should have slowed it all down, just like the Earth slows down the ball. But that’s not what they found.

Instead, everything seems to have sped up. There’s something pervading the Universe that physically spreads space apart faster than gravity can pull things together. The effect is small - it’s only noticeable when you look at far-away galaxies - but it’s there. It’s become known as dark energy - "dark", because no one knows what it is.

Science is nothing if not the process of humans looking for things they can’t explain, so this isn’t the first time the Universe has stumped us. For centuries, one of those stumpers has been time itself: Why does time have an arrow pointing from the past to the present to the future?

It might seem like a silly question - I mean, if time didn’t go forward, then effects would precede causes, and that seems like it should be impossible - but it’s less of one than you might think.

The Universe, as far as we can tell, only operates according to laws of physics. And just about all of the laws of physics that we know are completely time-reversible, meaning that the things they cause look exactly the same whether time runs forward or backward.

One example is the path of a planet going around a star, which is governed by gravity. Whether time runs forward or backward, planetary orbits follow the exact same paths. The only difference is the direction of the orbit.

But one important piece of physics isn’t time-reversible, and that’s the second law of thermodynamics. It states that as time moves forward, the amount of disorder in the Universe will always increase. Just like dark energy, it’s something we’ve noticed about the Universe, and it’s something that we still don’t totally understand - though admittedly we have a better idea of it than we do of dark energy.

Physicists have, for this reason, reluctantly settled on the second law as the source of time’s arrow: disorder always has to increase after something happens, which requires that time can only move in one direction.

So physicists A. E. Allahverdyan from the Yerevan Physics Institute and V. G. Gurzadyan from Yerevan State University, both in Armenia, decided to see if - at least in a limited situation - dark energy and the second law might be related. To test it, they looked at the simple case of something like a planet orbiting a star with a changing mass.

They found that if dark energy either doesn’t exist or if it pulls space together, the planet just dully orbits the star without anything interesting happening. There’s no way to tell an orbit going forward in time from one going backward in time.

But if dark energy pushes space apart, like it does in our Universe, the planet eventually gets thrown away from the star on a path of no return. This gives us a distinction between the past and the future: run time one way, and the planet is flung off, run it the other way, and the planet comes in and gets captured by the star.

Dark energy naturally leads to an arrow of time. The authors stress that this is a really limited situation, and they’re certainly not claiming dark energy is the reason time only ever moves forward. But they’ve shown a possible link between thermodynamics and dark energy that could help us to understand either - or maybe both - better than we ever have.

The research has been published in Physical Review E.


Via Kim Frye, Tania Gammage, The Planetary Archives / San Francisco, California, CineversityTV
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Of monsters, moonshine and shadows

Of monsters, moonshine and shadows | Amazing Science | Scoop.it
Monsters, moonshine and shadows sound like the ingredients for an excellent fairy tale. They are also part of a fascinating mathematical story that brings together some of our favorite things – number theory, group theory, string theory and even quantum gravity – as well as some of our favorite mathematicians.
 
The monster in question comes from group theory – the mathematical study of symmetry. A group is a set of things (usually called elements) and a rule for how these elements interact so the resulting system is self contained and satisfies some simple rules. You can read all the details in The power of groups.
 
One of the original inspirations for group theory came from studying symmetry groups – the symmetries that can exists together in an object. For example the symmetries of a rectangle are reflection in the vertical axis, reflection in the horizontal axis and a half-turn around the centre. These symmetries of a rectangle, together with the identity symmetry (that does nothing), form the Klein 4-group – one of the smallest groups.
 
There are also infinite groups, such as the set of whole numbers which form a group under addition. But every group, finite or infinite, is made up of building blocks called simple groups in an analogous way to every number being uniquely expressible as a product of prime factors.
 
One of the greatest mathematical achievements of the last century was the classification of the finite simple groups, an enormous theorem that took over 30 years, 100 mathematicians and 10,000 pages to prove. This result gave a description of every type of finite simple group: they were either one of 18 well-understood infinite families (such as addition modulo a prime number, eg. addition modulo 7) or they were one of 26 other individual possibilities (called the sporadic groups). The largest of these 26 outsiders is the Monster group, which consists of a mind-boggling

808,017,424,794,512,875,886,459,904,961,710,757,005,754,368,000,000,000

symmetries.

 

It turns out that every group, whether it's the symmetries of a rectangle or the whole numbers under addition, can be represented using mathematical objects called matrices. These are extensions of one-dimensional linear functions, such as , to higher dimensions. Each element of the group corresponds to a matrix that acts in -dimensional space, and these matrices behave in the same way that the original group elements (that is if for elements , and in the group, then for the corresponding matrices , and in the group's representation).

 

A single group can even have several different representations in terms of matrices. The smallest irreducible representation of the Monster group is as a group of matrices representing rotations in 196,883-dimensional space. The next largest is in 21,296,876-dimensional space, the one after that is in 842,609,326-dimensional space, and there are 194 such representations of the Monster group (including the trivial 1-dimensional one where all elements of the group act like the identity) in all.

 

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Kepler Mission Announces Largest Planet Collection Ever Discovered

Kepler Mission Announces Largest Planet Collection Ever Discovered | Amazing Science | Scoop.it
NASA's Kepler mission has verified 1,284 new planets – the single largest finding of planets to date.

 

“This announcement more than doubles the number of confirmed planets from Kepler,” said Ellen Stofan, chief scientist at NASA Headquarters in Washington. “This gives us hope that somewhere out there, around a star much like ours, we can eventually discover another Earth.” 

 

Analysis was performed on the Kepler space telescope’s July 2015 planet candidate catalog, which identified 4,302 potential planets. For 1,284 of the candidates, the probability of being a planet is greater than 99 percent – the minimum required to earn the status of “planet.” An additional 1,327 candidates are more likely than not to be actual planets, but they do not meet the 99 percent threshold and will require additional study. The remaining 707 are more likely to be some other astrophysical phenomena. This analysis also validated 984 candidates previously verified by other techniques.

 

"Before the Kepler space telescope launched, we did not know whether exoplanets were rare or common in the galaxy. Thanks to Kepler and the research community, we now know there could be more planets than stars,” said Paul Hertz, Astrophysics Division director at NASA Headquarters. "This knowledge informs the future missions that are needed to take us ever-closer to finding out whether we are alone in the universe."

 

Kepler captures the discrete signals of distant planets – decreases in brightness that occur when planets pass in front of, or transit, their stars – much like theMay 9 Mercury transit of our sun. Since the discovery of the first planets outside our solar system more than two decades ago, researchers have resorted to a laborious, one-by-one process of verifying suspected planets.

 

This latest announcement, however, is based on a statistical analysis method that can be applied to many planet candidates simultaneously. Timothy Morton, associate research scholar at Princeton University in New Jersey and lead author of the scientific paper published in The Astrophysical Journal, employed a technique to assign each Kepler candidate a planet-hood probability percentage – the first such automated computation on this scale, as previous statistical techniques focused only on sub-groups within the greater list of planet candidates identified by Kepler.

 

"Planet candidates can be thought of like bread crumbs,” said Morton. “If you drop a few large crumbs on the floor, you can pick them up one by one. But, if you spill a whole bag of tiny crumbs, you're going to need a broom. This statistical analysis is our broom."

 

In the newly-validated batch of planets, nearly 550 could be rocky planets like Earth, based on their size. Nine of these orbit in their sun's habitable zone, which is the distance from a star where orbiting planets can have surface temperatures that allow liquid water to pool. With the addition of these nine, 21 exoplanets now are known to be members of this exclusive group.

 

"They say not to count our chickens before they're hatched, but that's exactly what these results allow us to do based on probabilities that each egg (candidate) will hatch into a chick (bona fide planet)," said Natalie Batalha, co-author of the paper and the Kepler mission scientist at NASA's Ames Research Center in Moffett Field, California. “This work will help Kepler reach its full potential by yielding a deeper understanding of the number of stars that harbor potentially habitable, Earth-size planets -- a number that's needed to design future missions to search for habitable environments and living worlds.”

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Twisted light with high orbital angular momentum travels slower than the speed of light

Twisted light with high orbital angular momentum travels slower than the speed of light | Amazing Science | Scoop.it

That the speed of light in free space c is constant has been a pillar of modern physics since the derivation of Maxwell and in Einstein’s postulate in special relativity.

 

That the speed of light in free space c is constant has been a pillar of modern physics since the derivation of Maxwell and in Einstein’s postulate in special relativity. This has been a basic assumption in light’s various applications. However, a physical beam of light has a finite extent such that even in free space it is by nature dispersive. The field confinement changes its wavevector, hence, altering the light’s group velocity vg. Here, a group of scientists now reports the subluminal vg and consequently the dispersion in free space of Laguerre-Gauss (LG) beam, a beam known to carry orbital angular momentum. The vg of LG beam, calculated in the paraxial regime, is observed to be inversely proportional to the beam’s divergence θ0, the orbital order ℓ and the radial order p. LG beams of higher orders travel relatively slower than that of lower orders. As a consequence, LG beams of different orders separate in the temporal domain along propagation. This is an added effect to the dispersion due to field confinement.

 

These results are useful for treating information embedded in LG beams from astronomical sources and/or data transmission in free space.

 

 

 

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Mirror-image polymerase copies mirror-world DNA

Mirror-image polymerase copies mirror-world DNA | Amazing Science | Scoop.it

Researchers at Tsinghua University in Beijing have created a mirror-image version of a protein that performs two of the most fundamental processes of life: copying DNA and transcribing it into RNA.

The work is a “small step” along the way to making mirror-image life forms, says molecular biologist Jack Szostak of Harvard Medical School in Boston, Massachusetts. “It’s a terrific milestone,” adds his Harvard colleague George Church, who hopes one day to create an entire mirror-image cell.

Many organic molecules are ‘chiral’: that is, they can exist in mirror-image forms that cannot be superimposed, like a right-handed and left-handed glove. But life almost always employs one version: cells use left-handed amino acids, and have DNA that twists like a right-handed screw, for instance.

 

Life forms created in this mirrored way would not be able to use any of the biological material of our normal world.

 

In their research paper, the Tsinghua researchers also present their work as an effort to investigate why life’s chirality is the way it is. This remains mysterious: it may simply be down to chance, or it could have been triggered by a fundamental asymmetry in nature.

 

But Steven Benner, at the Foundation for Applied Molecular Evolution in Alachua, Florida, says it’s unlikely that creating a mirror form of biochemical life could shed any light on this question. Almost every physical process behaves identically when viewed in a mirror. The only known exceptions — called ‘parity violations’ — lie in the realm of subatomic physics. Such tiny differences would never show up in these biochemical experiments, says Benner. (He is also interested in making DNA that can avoid unwanted degradation by natural enzymes or viruses, but rather than using mirror-DNA, he has created artificial DNA with non-natural building blocks.)

 

Church’s ultimate goal, to make a mirror-image cell, faces enormous challenges. In nature, RNA is translated into proteins by the ribosome, a complex molecular machine. “Reconstructing a mirror-image of the ribosome would be a daunting task,” says Zhu. Instead, Church is trying to mutate a normal ribosome so that it can handle mirror-RNA.

 

Church says that it is anyone’s guess as to which approach might pay off. But he notes that a growing number of researchers are working on looking-glass versions of biochemical processes. “For a while it was a non-field,” says Church. “But now it seems very vibrant.”

 

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Cancer-patient big data can save lives if shared globally

Cancer-patient big data can save lives if shared globally | Amazing Science | Scoop.it

Sharing genetic information from millions of cancer patients around the world could revolutionize cancer prevention and care, according to a paper in Nature Medicine by the Cancer Task Team of the Global Alliance for Genomics and Health (GA4GH). Hospitals, laboratories and research facilities around the world hold huge amounts of this data from cancer patients, but it’s currently held in isolated “silos” that don’t talk to each other, according to GA4GH, a partnership between scientists, clinicians, patients, and the IT and Life Sciences industry, involving more than 400 organizations in over 40 countries. GA4GH intends to provide a common framework for the responsible, voluntary and secure sharing of patients’ clinical and genomic data.

 

“Imagine if we could create a searchable cancer database that allowed doctors to match patients from different parts of the world with suitable clinical trials,” said GA4GH co-chair professor Mark Lawler, a leading cancer expert fromQueen’s University Belfast. “This genetic matchmaking approach would allow us to develop personalized treatments for each individual’s cancer, precisely targeting rogue cells and improving outcomes for patients.

 

“This data sharing presents logistical, technical, and ethical challenges. Our paper highlights these challenges and proposes potential solutions to allow the sharing of data in a timely, responsible and effective manner. We hope this blueprint will be adopted by researchers around the world and enable a unified global approach to unlocking the value of data for enhanced patient care.”

 

GA4GH acknowledges that there are security issues, and has created a Security Working Group and a policy paper that documents the standards and implementation practices for protecting the privacy and security of shared genomic and clinical data.

 

Examples of current initiatives for clinico-genomic data-sharing include the U.S.-based Precision Medicine Initiative and the UK’s 100,000 Genomes Project, both of which have cancer as a major focus.

 

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Bionic Spinal Cord Lets You Move Robotic Limbs With Power of Thought

Bionic Spinal Cord Lets You Move Robotic Limbs With Power of Thought | Amazing Science | Scoop.it

Australian researchers have created a “bionic spinal cord.” They claim that this device could give paralyzed people significant hope of walking again. And if that’s not enough, it could do it utilizing the power of thought and without the necessity of open brain surgery.

 

A research team from the Vascular Bionics Laboratory at the University of Melbourne developed the novel neural-recording device, which both eschews invasive surgery and decreases the risks of a blood-brain barrier breach by being implanted into the brain’s blood vessels.

 

Developed under DARPA’s Reliable Neural-Interface Technology (RE-NET) program, the Stentrode can potentially safely expand the use of brain-machine interfaces (BMIs) in the treatment of physical disabilities and neurological disorders.

 

The researchers describe their “proof-of-concept results” which come from a study conducted on sheep, demonstrating high-fidelity measurements taken from the region of the brain responsible for controlling voluntary movement (called the motor cortex) with the use of the novel device which, as it happens, is just about the size of a paperclip.

 

Notably, the device records neural activity that has been shown in pre-clinical trials to move limbs through an exoskeleton.

 

The team, led by neurologist Thomas Oxley, M.D., published their study in an article in the journal Nature Biotechnology.


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Scientists hold closed meeting to discuss building a human genome from scratch

Scientists hold closed meeting to discuss building a human genome from scratch | Amazing Science | Scoop.it

More than 130 scientists, lawyers, entrepreneurs, and government officials from five continents gathered at Harvard this week for an “exploratory” meeting to discuss the topic of creating genomes from scratch — including, but not limited to, those of humans, said George Church, Harvard geneticist and co-organizer of the meeting.  The meeting was closed to the press, which drew the ire of prominent academics.

 

Synthesizing genomes involves building them from the ground up — chemically combining molecules to create DNA. Similar work by Craig Venter in 2010 created what was hailed as the first synthetic cell, a bacterium with a comparatively small genome.

 

In recent months, Church has been vocal in saying that the much-hyped genome-editing technology called CRISPR, which is only a few years old and which he helped develop, would soon be obsolete. Instead of changing existing genomes through CRISPR, Church has said, scientists could build exactly the genomes they want from scratch, by stringing together off-the-shelf DNA letters.

 

The topic is a heavy one, touching on fundamental philosophical questions of meaning and being. If we can build a synthetic genome — and eventually, a creature — from the ground up, then what does it mean to be human?

 

“This idea is an enormous step for the human species, and it shouldn’t be discussed only behind closed doors,” said Laurie Zoloth, a professor of religious studies, bioethics, and medical humanities at Northwestern University.

 

In response, she co-authored an article with Drew Endy, a bioengineering professor at Stanford University, calling for broader conversations around the research.

 

Church said that the meeting was originally going to be “an open meeting with lots of journalists engaged.” It was supposed to be accompanied by a peer-reviewed article on the topic. But, he said, the journal (which Church declined to identify) wanted the paper to include more information about the ethical, social, and legal components of synthesizing genomes — things that were discussed at the meeting.

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Physicists measure van der Waals forces of individual atoms for the first time

Physicists measure van der Waals forces of individual atoms for the first time | Amazing Science | Scoop.it

Physicists at the Swiss Nanoscience Institute and the University of Basel have succeeded in measuring the very weak van der Waals forces between individual atoms for the first time. To do this, they fixed individual noble gas atoms within a molecular network and determined the interactions with a single xenon atom that they had positioned at the tip of an atomic force microscope. As expected, the forces varied according to the distance between the two atoms; but, in some cases, the forces were several times larger than theoretically calculated. These findings are reported by the international team of researchers in Nature Communications.

 

Van der Waals forces act between non-polar atoms and molecules. Although they are very weak in comparison to chemical bonds, they are hugely significant in nature. They play an important role in all processes relating to cohesion, adhesion, friction or condensation and are, for example, essential for a gecko's climbing skills.

 

Van der Waals interactions arise due to a temporary redistribution of electrons in the atoms and molecules. This results in the occasional formation of dipoles, which in turn induce a redistribution of electrons in closely neighboring molecules. Due to the formation of dipoles, the two molecules experience a mutual attraction, which is referred to as a van der Waals interaction. This only exists temporarily but is repeatedly re-formed. The individual forces are the weakest binding forces that exist in nature, but they add up to reach magnitudes that we can perceive very clearly on the macroscopic scale - as in the example of the gecko.

 

To measure the van der Waals forces, scientists in Basel used a low-temperature atomic force microscope with a single xenon atom on the tip. They then fixed the individual argon, krypton and xenon atoms in a molecular network. This network, which is self-organizing under certain experimental conditions, contains so-called nano-beakers of copper atoms in which the noble gas atoms are held in place like a bird egg. Only with this experimental set-up is it possible to measure the tiny forces between microscope tip and noble gas atom, as a pure metal surface would allow the noble gas atoms to slide around.

 

The researchers compared the measured forces with calculated values and displayed them graphically. As expected from the theoretical calculations, the measured forces fell dramatically as the distance between the atoms increased. While there was good agreement between measured and calculated curve shapes for all of the noble gases analyzed, the absolute measured forces were larger than had been expected from calculations according to the standard model. Above all for xenon, the measured forces were larger than the calculated values by a factor of up to two.


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Five genes identified that give your nose its shape

Five genes identified that give your nose its shape | Amazing Science | Scoop.it

Whether you have a huge honker, a puny proboscis, or a snubbed schnoz, the shape of your nose is in your genes. Now, researchers have sniffed out five of those stretches of DNA that control nose and chin shape. The team sequenced the genomes of more than 6000 men and women in Central and South America and used photographs of the participants to categorize 14 of their facial features—from cheekbone protrusion to lip shape. Then, the scientists analyzed whether any of the features were associated with certain genes. GLI3 and PAX1, both known to be involved in cartilage growth, were linked to the breadth of a person’s nostrils;DCHS2, also related to cartilage, controlled nose pointiness; RUNX2, which drives bone development, was associated with the width of the nose bridge, the upper area of the nose; and EDAR, which has previously been linked to ear and tooth shape and hair texture, affected chin protrusion. The results, published online today in Nature Communications, may help shed light on how the human face evolved and why different ethnicities have distinct facial features. Moreover, the research could help forensic scientists reconstruct faces based on genetic samples.

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Study captures ultrafast motion of proteins

Study captures ultrafast motion of proteins | Amazing Science | Scoop.it

A new study by an international team of researchers, affiliated with Ulsan National Institute of Science and Technology (UNIST) has announced that they have succeeded for the first time in observing the structural change.

 

The breakthrough comes from a research, conducted by Professor Chae Un Kim (School of Natural Science) of UNIST in collaboration with researchers from Soongsil University, Cornell University, and University of Florida. Carbonic anhydrase, which is found within red blood cells, is a crucial enzyme that stabilizes carbon dioxide (CO2 ) concentrations. This enzyme catalyzes a reaction converting CO2 and water into carbonic acid, which associates into protons and bicarbonate ions.

 

Moreover, it is also known that carbonic anhydraseis is able to catalyze at a rate of 106 reactions per second. In the absence of this catalyst, the conversion from CO2 to bicarbonate, and vice versa, would be extremely slow and difficult.

 

One of the important functions of the enzyme in humans is to adjust the acidity of the chemical environment to prevent damage to the body, as well as to help transport carbon dioxide out from tissue cells to the lungs. Although carbonic anhydrase performs a lot of beneficial functions, defects in the enzyme are responsible for developing diseases, such as glaucoma, acidemia, or osteopetrosis.

 

Prof. Kim, the lead researcher of the study states, "The reaction rate of carbonic anhydrase is one of the fastest of all enzymes." He continues, "Due to the rapid movement of proteins, direct observation for such movement has been extremely difficult to obtain, protein scientists say."

 

In this study, Prof. Kim's team used their own method of "High-pressure Crycooling" and "X-ray Crystallography" to capture the gaseous carbon dioxide in crystals of carbonic anhydrase and follow the sequential structure changes as the carbon dioxide is released. The results of the study will not only greatly contribute to the future biomedical research and new drug development, but will also help make carbon capture more economic.

 

According to Prof. Kim of UNIST, "This study also shows technical methods that may be applicable to other enzymes that bind and react to low-molecular weight substrates, such as CO2 and NO2 ."


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Mystery mounds in Colombia are actually giant piles built by earthworms

Mystery mounds in Colombia are actually giant piles built by earthworms | Amazing Science | Scoop.it

During the rainy season in the Orinoco Llanos of Columbia and Venezuela, an odd landscape feature appears in places: mounds of grassy plants, as big as five meters across and two meters tall, surrounded by water. Traversing this landscape, called surales, requires either hopping from mound to mound or trudging through the boggy bits in between.

 

Locals and scientists have generally agreed that some kind of earthworm creates the mounds, but what species and how it does so has been a mystery. Now Anne Zangerlé of the Braunschweig University of Technology in Germany and colleagues report that they’ve found the culprit — giant Andiorrhinus earthworms, which can grow to a meter in length as juveniles. And the mounds themselves, the team reports May 11 in PLOS ONE, are actually made mostly of earthworm poop.

 

Zangerlé and her colleagues used Google Earth images to locate surales landscapes, finding that they come in the shape of both mounds and labyrinths. Leaving the complex labyrinths for a future study, the team studied the mounds and the lands on which they were found in both the rainy and dry seasons. They characterized the soil and the plants and worms living in and on the mounds. And then they pieced all of that information together to come up with a scenario that they think explains the construction of the mounds.

 


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Intron Addition into Genome Detected as an Ultra-rare Event

Intron Addition into Genome Detected as an Ultra-rare Event | Amazing Science | Scoop.it

After nearly a half trillion tries, a rare event was seen that might solve an evolutionary puzzle about noncoding sequences of DNA in genomes and address speciation and the cause of diseases like cancer.

 

For a long time, scientists have known that much of the DNA within any given organism’s genome does not code for functional molecules or protein. However, recent research has found that these genetic sequences, misnamed “junk” DNA in the past, often do have functional significance. These introns are no exception. Now known to play a role in gene expression, introns are the portion of gene sequences that are removed or spliced out of RNA before genes are translated into protein. When eukaryotes first diverged from bacteria, there was a massive invasion of introns into the genome. All living eukaryotes — from yeast to mammals — share this common ancestor, and whereas simple organisms such as yeast have eliminated most of their introns, organisms such as mammals have considerably expanded their intron inventory. Humans have more than 200,000 introns that take up about 40 percent of the genome.

 

In a current paper, Stevens and co-author Sujin Lee, a former graduate student in cellular and molecular biology at UT Austin, used a new reporter assay to directly detect the loss and gain of introns in budding yeast (Saccharomyces cerevisiae). The team tested nearly a half trillion yeast and found only two instances in which an intron was added to a new gene. The proposed mechanism for this addition is a reversal of a splicing reaction.

 

Normally, to make proteins, RNA is read from the instructions in DNA, and the introns are spliced out. But in these two instances, the cell allowed the spliced out introns to make it back into a different RNA and was recombined back into the genome, thus creating a permanent genetic change. These are called intron gains, and if these accumulate over time, they can contribute to the development of new species as well as human disease.

 

“We showed in this project that introns continue to be gained, although infrequently at any point in time,” says Stevens. “But can introns drive evolution? If these sequences give organisms a selective advantage and become fixed in a population, others have shown that it can be a major factor in the creation of new species.”

 

These evolutionary advances come at a cost, however, because diseases such as cancer correlate with the improper removal of introns from RNA. Stevens adds, “We are continuing this work to further understand how this process impacts our genetic history, our future, and the prospects of curing disease.”


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Using Natural Killer Cells within us to Fight Cancer

Using Natural Killer Cells within us to Fight Cancer | Amazing Science | Scoop.it

Our bodies are constantly and successfully fighting off the development of cells that lead to tumors - but when there is disruption to this process cancer is free to develop.

Walter and Eliza Hall Institute researchers, led by Dr Sandra Nicholson and Dr Nicholas Huntington, together with colleagues from the Queensland Institute of Medical Research, are investigating ways to 'switch on' our Natural Killer (NK) cells.

 

Natural Killer cells exist to detect and then destroy any deviant cells in our bodies before those cells go on to develop into tumors or before infection spreads, Dr Nicholson said. "Natural Killer cells are a key part of our immune system that locate other cells posing a danger to health either because they are infected or because they are becoming a cancer cell," she said. However, it is known that abnormal cells sometimes escape the immune system and develop into a cancer.

 

The researchers identified a protein 'brake' within Natural Killer cells that controls their ability to destroy their target tumor cells.

In their paper published today in Nature Immunology, they showed that when the brake was removed in an experimental model, the NK cells were better able to protect the body against metastatic melanoma.

 

Natural Killer cells rely on a growth factor called Interleukin 15 (IL15) to activate. Dr Nicholson and Dr Huntington's research has shown that an inhibitor protein made inside the Natural Killer cells limits the ability of the NK cell to respond to IL15 and therefore kill cancer cells. By identifying for the first time how this protein inhibits NK cell responses, they now hope that a drug can be developed that will improve the NK cells' response to this growth factor and help patients fight cancer with their own immune system. "This is about learning how to activate the NK cells of the individual patient and boost their immune system to tackle the disease," Dr Huntington said.


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