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Scooped by Dr. Stefan Gruenwald!

2Smart4Mankind: Google Has An Internal Committee To Discuss Its Fears About The Power Of Artificial Intelligence

2Smart4Mankind: Google Has An Internal Committee To Discuss Its Fears About The Power Of Artificial Intelligence | Amazing Science |

Robots are coming. Google has assembled a team of experts in London who are working to "solve intelligence." They make up Google DeepMind, the US tech giant's artificial intelligence (AI) company, which it acquired in 2014. In an interview with MIT Technology Review, published recently, Demis Hassabis, the man in charge of DeepMind, spoke out about some of the company's biggest fears about the future of AI.

Hassabis and his team are creating opportunities to apply AI to Google services. AI firm is about teaching computers to think like humans, and improved AI could help forge breakthroughs in loads of Google's services. It could enhance YouTube recommendations for users for example, or make the company's mobile voice search better.

But it's not just Google product updates that DeepMind's cofounders are thinking about. Worryingly, cofounder Shane Legg thinks the team's advances could be what finishes off the human race. He told the LessWrong blog in an interview: "Eventually, I think human extinction will probably occur, and technology will likely play a part in this". He adds he thinks AI is the "no.1 risk for this century". It's ominous stuff. (Read about Elon Musk discussing his concerns about AI here.)

People like Stephen Hawking and Elon Musk are worried about what might happen as a result of advancements in AI. They're concerned that robots could grow so intelligent that they could independently decide to exterminate humans. And if Hawking and Musk are fearful, you probably should be too.

Hassibis showcased some DeepMind software in a video back in April. In it, a computer learns how to beat Atari video games — it wasn't programmed with any information about how to play, just given the controls and an instinct to win. AI specialist Stuart Russell of the University of California says people were "shocked".

Google is also concerned about the "other side" of developing computers in this way. That's why it set up an "ethics board". It's tasked with making sure AI technology isn't abused. As Hassibis explains: "It's (AI) something that we or other people at Google need to be cognizant of." Hassibis does concede that "we're still playing Atari games currently" — but as AI moves forward, the fear sets in.

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The #1 reason people die early, in each country

The #1 reason people die early, in each country | Amazing Science |

You're probably aware that heart disease and cancer are far and away the leading causes of death in America. But globally the picture is more complicated: The above map shows the leading cause of lost years of life by country (click to see a larger version). The data comes from the Global Burden of Disease study, whose 2013 installment was released just a few weeks ago. It's worth stressing that "cause of lost years of life" and "cause of death" aren't identical. For example, deaths from preterm births may cause more lost years of life in a country than deaths from heart disease even if heart disease is the leading cause of death. Deaths from preterm births amount to many decades of lost life, whereas heart disease tends to develop much later on.

But that makes the fact that heart disease is the leading cause of lost life in so many countries all the more striking, and indicative of those countries' successes in reducing childhood mortality. By contrast, in many lower-income countries, the leading cause is something like malaria, diarrhea, preterm birth, HIV/AIDS, or violence, which all typically afflict people earlier in life than heart disease or stroke. We've made considerable progress in fighting childhood mortality across the globe in recent decades, but there's still much work left to be done.

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Amazing Story: Man Saves Wife's Sight by 3D Printing Her Tumor

Amazing Story: Man Saves Wife's Sight by 3D Printing Her Tumor | Amazing Science |

Two highly motivated stakeholders (the patient and her husband) had access to the patient’s medical data and were able to enhance its value using new era tools (software and 3D printing) and bring it to the docs – clearer – so they could better apply their clinical skills. Specifically, the physicians who read the scans before had not seen the situation clearly. With the tumor printed, a better picture emerged. That is adding value in medicine.

Want to print your medical image? Ask your doctor for your DICOM files and download 3D Slicer ( Then use the Region Growing tool to segment the image. Extract a 3D mesh of the surface, save as an STL, and use ParaView ( to simplify it to a manageable number of triangles. To see more details, check out Make: volume 42, page 83, or visit projects/3d-print-your-medical-scan.

Full story is here:

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The Neural Turing Machine (NTM) — Google's DeepMind AI project

The Neural Turing Machine (NTM) — Google's DeepMind AI project | Amazing Science |

The mission of Google’s DeepMind Technologies startup is to “solve intelligence.” Now, researchers there have developed an artificial intelligence system that can mimic some of the brain’s memory skills and even program like a human. The researchers developed a kind of neural network that can use external memory, allowing it to learn and perform tasks based on stored data.

The so-called Neural Turing Machine (NTM) that DeepMind researchers have been working on combines a neural network controller with a memory bank, giving it the ability to learn to store and retrieve information. The system’s name refers to computer pioneer Alan Turing’s formulation of computers as machines having working memory for storage and retrieval of data.

The researchers put the NTM through a series of tests including tasks such as copying and sorting blocks of data. Compared to a conventional neural net, the NTM was able to learn faster and copy longer data sequences with fewer errors. They found that its approach to the problem was comparable to that of a human programmer working in a low-level programming language.

The NTM “can infer simple algorithms such as copying, sorting and associative recall from input and output examples,” DeepMind’s Alex Graves, Greg Wayne and Ivo Danihelka wrote in a research paper available on the arXiv repository.

“Our experiments demonstrate that it is capable of learning simple algorithms from example data and of using these algorithms to generalize well outside its training regime.”

A spokesman for Google declined to provide more information about the project, saying only that the research is “quite a few layers down from practical applications.” In a 2013 paper, Graves and colleagues showed how they had used a technique known as deep reinforcement learning to get DeepMind software to learn to play seven classic Atari 2600 video games, some better than a human expert, with the only input being information visible on the game screen.

Google confirmed earlier this year that it had acquired London-based DeepMind Technologies, founded in 2011 as an artificial intelligence company. The move is expected to have a major role in advancing the search giant’s research into robotics, self-driving cars and smart-home technologies.

More recently, DeepMind co-founder Demis Hassabis wrote in a blog post that Google is partnering with artificial intelligence researchers from Oxford University to study topics including image recognition and natural language understanding.

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How DNA Sequencing In Sewers Could Detect Disease Outbreaks

How DNA Sequencing In Sewers Could Detect Disease Outbreaks | Amazing Science |

Disease prevention and mapmaking have been inextricably intertwined since 1854, when an English physician named John Snow plotted a cholera outbreak on a grid to locate–and shut down–a bacteria-tainted water pump, inventing the modern science of epidemiology along the way.

In 2010 geneticist Eric Schadt, then the chief scientific officer at DNA sequencer maker Pacific Biosciences, had a brainstorm as to how to update Snow’s breakthrough for the modern age. The germs that infect us–everything from influenza to measles to bubonic plague–wind up in our waste. Why not look for them by using DNA technology to sequence raw sewage?

Snippets of DNA in wastewater could then be matched to known pathogens–and specific physical locations. Public health officials would no longer have to wait for someone to spike a fever to know that Ebola virus was in Manhattan–they would be alerted by the sequences coming from the sewers, and they would know within a few blocks where it was.

Schadt tried the project out using samples from the San Francisco sewers, but bringing sewage back to PacBio’s expensive, heavy sequencers was impractical at best. Christopher Mason, a Weill Cornell Medical College professor, has picked up a simpler version of the idea, applying swabs to surfaces all over New York City to create a “Pathomap” of germs that will be unveiled early next year.

But Schadt, who now heads a sweeping Carl Icahn-funded genomics effort at the Mount Sinai School of Medicine in Manhattan, still wants a more detailed map produced automatically from sewage. Possible? One new DNA sequencer, made by Oxford Nanopore, is a thumb drive that can take sequences on the spot. Who knows what another generation of innovation could bring? Says Mason: “It’s futuristic, but not unrealistic.”

Via Integrated DNA Technologies
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Your Odds Of Surviving Cancer Depend Very Much On Where You Live

Your Odds Of Surviving Cancer Depend Very Much On Where You Live | Amazing Science |
The largest study of cancer patients reveals a huge gulf in survival rates around the world. And in some countries, there may only be one cancer doctor for the entire population.

In the United States, 9 out of 10 kids diagnosed with acute lymphoblastic leukemia will live. In Jordan, the survival rate is 16 percent. And while cervical cancer patients have a five-year survival rate of over 70 percent in countries like Mauritius and Norway, the rate in Libya is under 40 percent.

That's the sobering news from the largest cancer study ever published. It surveyed more than 25.7 million patients and reveals a huge gulf in cancer survival worldwide. But there's good news as well. "In most countries, survival from some of the commonest cancers has been improving," says Dr. Michel Coleman from the London School of Hygiene and Tropical Medicine, one of the study's authors.

More people are surviving breast cancer, colon cancer and stomach cancer than ever before, especially in the U.S. and Europe. The survival rate for breast cancer in France and Finland, for example, is 87 percent. The data from other regions are also encouraging. Brazil's breast cancer survival rate has gone up from 78 percent in 1995-99 to 87 percent in 2005-09.

The reason that some countries lag behind is not surprising; it's a matter of how much is invested in cancer care. Dr. Corey Casper, head of global oncology at the Fred Hutchinson Cancer Research Center in Seattle, met a doctor in Uganda a few years ago who was then seeing 10,000 patients a year "in a facility that had ... no roof, inconsistent electricity and no meds." What's more, says Casper, he was the only cancer doctor in Uganda and four surrounding countries.

In summary, the study found that 5-year survival from colon, rectal, and breast cancers has increased steadily in most developed countries. For patients diagnosed during 2005–09, survival for colon and rectal cancer reached 60% or more in 22 countries around the world; for breast cancer, 5-year survival rose to 85% or higher in 17 countries worldwide. Liver and lung cancer remain lethal in all nations: for both cancers, 5-year survival is below 20% everywhere in Europe, in the range 15–19% in North America, and as low as 7–9% in Mongolia and Thailand. Striking rises in 5-year survival from prostate cancer have occurred in many countries: survival rose by 10–20% between 1995–99 and 2005–09 in 22 countries in South America, Asia, and Europe, but survival still varies widely around the world, from less than 60% in Bulgaria and Thailand to 95% or more in Brazil, Puerto Rico, and the USA. For cervical cancer, national estimates of 5-year survival range from less than 50% to more than 70%; regional variations are much wider, and improvements between 1995–99 and 2005–09 have generally been slight. For women diagnosed with ovarian cancer in 2005–09, 5-year survival was 40% or higher only in Ecuador, the USA, and 17 countries in Asia and Europe. 5-year survival for stomach cancer in 2005–09 was high (54–58%) in Japan and South Korea, compared with less than 40% in other countries. By contrast, 5-year survival from adult leukaemia in Japan and South Korea (18–23%) is lower than in most other countries. 5-year survival from childhood acute lymphoblastic leukaemia is less than 60% in several countries, but as high as 90% in Canada and four European countries, which suggests major deficiencies in the management of a largely curable disease.

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Why Billions of Exoplanets Are Suddenly Looking Much More Habitable Than Before

Why Billions of Exoplanets Are Suddenly Looking Much More Habitable Than Before | Amazing Science |
A new astrophysics study just raised the chances for finding life on exoplanets across the universe.

If you're on the hunt for Earth-like planets that can sustain life, then your best bet might not be stars that look like our sun, but smaller, cooler stars—orange and red dwarfs. These, on average, have been found to host more Earth-sized planets, and they are far and away the most abundant. They make up more than 75 percent of the stars in our universe, and nearly every red dwarf star has at least one exoplanet

But there's a potentially fatal flaw here: When exoplanets orbiting these stars are the right distance to hold liquid water, they tend suffer from what astronomers call rotational lockup. Much like how one side of our Moon always faces the Earth, one side of the planet always faces its star. With an always-day desert on one side and an arctic hellscape on the other, any planet's chance of being habitable looks far less likely. 

Here comes some good news, though. A team of astrophysicists has announced that this thinking could be wrong—rotational lockup is not necessarily the rule for these exoplanets. As they report in the journal Science, the simple existence of an atmosphere (even one as thin as Earth's) can keep a planet twirling and habitable. According to Jérémy Leconte, the theoretical astrophysicist at the University of Toronto who lead the team that made this discovery, the finding means that a large number of already discovered Earth-like planets might be a lot more habitable than we thought. "Planets with potential oceans could thus have a climate that is much more similar to the Earth's than we've previously expected," he says.

So how does an atmosphere cause a planet to spin faster? Jeff Coughlin, a SETI astronomer working with Kepler planet-hunting mission (who was not involved in the research), explains it this way: "On Earth, light from the sun is what drives the weather in our atmosphere. And that weather, in the form of wind, constantly pushes against the planet—running into mountains, for example, or creating waves on the ocean. This friction is deposited in the rotation rate of our planet, helping to speed it up or slow it down." 

Astrophysicists knew this. But, Coughlin says, scientists also believed that for an atmosphere to have an appreciable impact on a locked planet's rotation, it'd have to be incredibly, almost absurdly massive. Consider the case of Venus, which is close enough to our sun to be locked up rotationally. That hellish planet spins just fast enough to escape lockup (so slowly that one Venus day lasts 243 Earth days). And Venus's atmosphere is enormous—around 90 times as dense as our own. 

But, when Leconte and his fellow researchers created and ran the first computer model of how an exoplanet's atmosphere might affect its rotation, they found something surprising. In fact, thinner atmospheres actually have a larger rotational effect on their planets. This might seem counterintuitive, but the reason seems to be that thinner atmospheres scatter less starlight. When starlight pierces into a planet’s atmosphere without scattering, the extra heat creates a stronger atmospheric tide (a bulging of atmosphere, much like our ocean’s tides) that yanks on the surface of the planet as it evens out, creating a stronger planetary rotation. 

Using this model, Leconte's team found that Earth-sized planets with an Earth-like atmosphere will spin healthily around stars as small as orange dwarfs and some red dwarfs. The same could be true for even smaller stars, depending on the size of a planet and thickness of its atmosphere. If Venus were to have an atmosphere like Earth's—90 percent less dense than its real atmosphere—then it would spin about 10 times faster. 

"More and more, we're discovering that there's a lot of ways to have a very nice, habitable planet around dwarf stars," Coughlin says.

Devin Julian Lee Sykes's curator insight, January 17, 2015 12:28 PM

Well this made me remember my childhood dreams of working towards being an astrophysicist and working with NASA.

Yumma Mudra's curator insight, January 22, 2015 3:11 AM

les planètes Terres

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Science Graphic of the Week: Perrenial Arctic Sea Ice Continues to Shrink

Science Graphic of the Week: Perrenial Arctic Sea Ice Continues to Shrink | Amazing Science |

For scientists concerned about the fate of the Arctic ice cap, one of the most important things to keep track of is the amount of ice that survives the summer. A new video shows how, despite growth during some years years, we’re progressively losing this mature, thicker ice.

Published on Jan. 12, 2015, by NASA’s Science Visualization Studio, this video tracks perennial sea ice from 1979-2014. To get a complete picture of multi-year ice, researchers had to carefully analyze their imagery day-by-day, and section-by-section. This is because different parts of the Arctic reach minimum sea ice at different times, and floating ice has a tendency to move.

The video builds on a study that was published in October in the journalGeophysical Research Letters. While the original study only tracked ice from 1979-2000, these 14 additional years of data show that even with a spike in 2000 and several recent years of growth, the Arctic is steadily, if spikily, melting.

In the short term, this will be good for global shipping, shortening the route between many huge markets, notably Europe and China. And because the dark ocean will absorb more of the sun’s heat, this will also trigger plankton blooms, meaning more productive oceans. But commercial fishing gains won’t last long, as warmer waters tend to attract huge jellyfish blooms, which crowd out other species.

And an ice-free Arctic would mostly benefit the few countries that have claims in the region. For the rest of the world, the melting sea ice will contribute to global warming’s negative consequences.

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By monitoring thousands of individual bacteria scientists discovered how they maintain their size

By monitoring thousands of individual bacteria scientists discovered how they maintain their size | Amazing Science |

Scientists have traditionally studied bacteria in large numbers, not individually. Working with tens of millions of cells in a culture flask, they tracked their growth by looking at how much the cells dimmed light passing through a tube. Using this method, scientists learned that populations of bacteria grow exponentially, doubling in mass at regular time intervals. And so, not unreasonably, they assumed that individual cells would do the same, dividing only when they have doubled in size.

In the Dec. 24 2014  online issue of Current Biology a group of scientists led by Suckjoon Jun of the University of California-San Diego, and including Petra Levin, PhD, associate professor of biology in Arts & Sciences at Washington University in St. Louis, report that this hypothesis was incorrect. “Even though on average it is true that mass doubles,” Levin said, “when you look at individual cells it becomes apparent that something else is going on.”

Instead of examining populations of cells growing in a flask or test tube, the Jun group instead used a microfluidics device called a “mother machine” to follow hundreds of thousands of individual cells from birth to division. They found that rather than doubling in size every generation, each cell added the same volume (or mass; the term reflects the measurement technique). Crucially a cell that was small added the same volume as a cell that was large. Why is this the rule? “Although this might seem counter-intuitive, over many generations this rule ensures that cells in a population maintain a constant size,” Levin said.

“This study really shows how new technologies, in this case the development of the ‘mother machine’ to visualize single bacteria in real time, can lead to new and unexpected answers to old problems,” Levin said. “Pinning down the growth rule is important,” she added, “because it provides clues to the underlying biochemical mechanism that ultimately controls growth. The mechanism is probably essential — or nearly so — and thus good target for new antimicrobials.”

Risto Suoknuuti's curator insight, January 16, 2015 1:15 AM

Tu stop the growth a Good rule good be that in division the added mass would decay stepwise exponentially.

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Researchers measure how fast electrons move through single atomic layers

Researchers measure how fast electrons move through single atomic layers | Amazing Science |
How fast do electrons whiz through the atomic layers of a crystal lattice? A team of scientists led by researchers from the Technische Universität München (TUM) joined by colleagues from the Max Planck Institute of Quantum Optics (MPQ), the Ludwig-Maximilians-Universität Munich and the Technical University of Vienna has now investigated this fundamental question. The researchers measured the time electrons needed to travel through a film consisting of a few layers a of magnesium atoms.

The time frames, in which electrons travel within atoms, are unfathomably short. For example, electrons excited by light change their quantum-mechanical location within mere attoseconds – an attosecond corresponds to a billionth of a billionth of a second. But how fast do electrons whiz across distances corresponding to the diameter of individual atomic layers? Such distances are but a few billionths of a metre. An international team of researchers led by Reinhard Kienberger, Professor for Laser and X-Ray Physics at the TUM and Head of a Research Group at the Max Planck Institute of Quantum Optics investigated the travel times of electrons over these extremely short distances.

To do so, the physicists applied a defined number of layers of magnesium atoms on top of a tungsten crystal. The researchers directed two pulses of light at these samples. The first pulse lasted approximately 450 attoseconds, at frequencies within the extreme ultraviolet. This light pulse penetrated the material and released an electron from a magnesium atom in the layer system as well as from an atom in the underlying tungsten crystal. Both the electrons that were set free stemmed from the immediate vicinity of the nucleus.

Once released, the "tungsten electron" and the "magnesium electron" travelled through the crystal to the surface at which point they left the solid body. (electrons from the tungsten crystal managed to penetrate up to four layers of magnesium atoms.) There, the particles were captured by the electric field of the second pulse, an infrared wave train lasting less than five femtoseconds.

As the "tungsten electron" and the "magnesium electron" reached the surface at different times due to different path lengths, they experienced the second pulse of infrared light at different times. That is, they were exposed to different strengths of the oscillating electric field. As a result, both particles were accelerated to varying degrees. From the resulting differences in the energy of the electrons, the researchers were able to determine how long an electron needed to pass through a single layer of atoms.

The measurements showed that upon release a "tungsten electron" possesses a speed of about 5,000 kilometers per second. When travelling through a layer of magnesium atoms it is delayed by approximately 40 attoseconds, i.e., this is exactly the time required to travel through this layer.

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Temporary tattoo could help diabetics manage their condition without daily finger pricks

Temporary tattoo could help diabetics manage their condition without daily finger pricks | Amazing Science |

Nanoengineers at the University of California, San Diego have tested a temporary tattoo that both extracts and measures the level of glucose in the fluid in between skin cells. This first-ever example of the flexible, easy-to-wear device could be a promising step forward in noninvasive glucose testing for patients with diabetes.

The sensor was developed and tested by graduate student Amay Bandodkar and colleagues in Professor Joseph Wang's laboratory at the NanoEngineering Department and the Center for Wearable Sensors at the Jacobs School of Engineering at UC San Diego. Bandodkar said this "proof-of-concept" tattoo could pave the way for the Center to explore other uses of the device, such as detecting other important metabolites in the body or delivering medicines through the skin.

At the moment, the tattoo doesn't provide the kind of numerical readout that a patient would need to monitor his or her own glucose. But this type of readout is being developed by electrical and computer engineering researchers in the Center for Wearable Sensors. "The readout instrument will also eventually have Bluetooth capabilities to send this information directly to the patient's doctor in real-time or store data in the cloud," said Bandodkar.

The research team is also working on ways to make the tattoo last longer while keeping its overall cost down, he noted. "Presently the tattoo sensor can easily survive for a day. These are extremely inexpensive--a few cents--and hence can be replaced without much financial burden on the patient."

A similar device called GlucoWatch from Cygnus Inc. was marketed in 2002, but the device was discontinued because it caused skin irritation, the UC San Diego researchers note. Their proof-of-concept tattoo sensor avoids this irritation by using a lower electrical current to extract the glucose.

Wang and colleagues applied the tattoo to seven men and women between the ages of 20 and 40 with no history of diabetes. None of the volunteers reported feeling discomfort during the tattoo test, and only a few people reported feeling a mild tingling in the first 10 seconds of the test.

To test how well the tattoo picked up the spike in glucose levels after a meal, the volunteers ate a carb-rich meal of a sandwich and soda in the lab. The device performed just as well at detecting this glucose spike as a traditional finger-stick monitor.

The researchers say the device could be used to measure other important chemicals such as lactate, a metabolite analyzed in athletes to monitor their fitness. The tattoo might also someday be used to test how well a medication is working by monitoring certain protein products in the intercellular fluid, or to detect alcohol or illegal drug consumption.

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Space-Based Solar Power May Arrive Sooner Than You Think

Space-Based Solar Power May Arrive Sooner Than You Think | Amazing Science |

The idea of capturing solar power in space for use as energy on Earth has been around since the beginning of the space age. In the last few years, however, scientists around the globe -- and several researchers at the Energy Department’s own Lawrence Livermore National Laboratory (LLNL) -- have shown how recent technological developments could make this concept a reality.

On earth, solar power is greatly reduced by night, cloud cover, atmosphere and seasonality. Some 30 percent of all incoming solar radiation never makes it to ground level. In space the sun is always shining, the tilt of the Earth doesn't prevent the collection of power and there’s no atmosphere to reduce the intensity of the sun’s rays. This makes putting solar panels into space a tempting possibility. Additionally, SBSP can be used to get reliable and clean energy to people in remote communities around the world, without relying on the traditional grid to a large local power plant.

Self-assembling satellites are launched into space, along with reflectors and a microwave or laser power transmitter. Reflectors or inflatable mirrors spread over a vast swath of space, directing solar radiation onto solar panels. These panels convert solar power into either a microwave or a laser, and beam uninterrupted power down to Earth. On Earth, power-receiving stations collect the beam and add it to the electric grid. The two most commonly discussed designs for SBSP are a large, deeper space microwave transmitting satellite and a smaller, nearer laser transmitting satellite.

Microwave transmitting satellites orbit Earth in geostationary orbit (GEO), about 35,000 km above Earth’s surface. Designs for microwave transmitting satellites are massive, with solar reflectors spanning up to 3 km and weighing over 80,000 metric tons. They would be capable of generating multiple gigawatts of power, enough to power a major U.S. city. The long wavelength of the microwave requires a long antenna, and allows power to be beamed through the Earth’s atmosphere, rain or shine, at safe, low intensity levels hardly stronger than the midday sun. Birds and planes wouldn’t notice much of anything flying across their paths.

The estimated cost of launching, assembling and operating a microwave-equipped GEO satellite is in the tens of billions of dollars. It would likely require as many as 40 launches for all necessary materials to reach space. On Earth, the rectenna used for collecting the microwave beam would be anywhere between 3 and 10 km in diameter, a huge area of land, and a challenge to purchase and develop.

Laser transmitting satellites, as described by our friends at LLNL, orbit in low Earth orbit (LEO) at about 400 km above the Earth’s surface. Weighing in in at less than 10 metric tons, this satellite is a fraction of the weight of its microwave counterpart. This design is cheaper too; some predict that a laser-equipped SBSP satellite would cost nearly $500 million to launch and operate. It would be possible to launch the entire self-assembling satellite in a single rocket, drastically reducing the cost and time to production. Also, by using a laser transmitter, the beam will only be about 2 meters in diameter, instead of several km, a drastic and important reduction.

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Earth Matters: What are the volcanoes with the highest energy emission on Earth?

Earth Matters: What are the volcanoes with the highest energy emission on Earth? | Amazing Science |

What is the hottest volcano of them all? It depends on how you define “hottest,” but a fascinating new analysis crunches the numbers in a few different ways, using satellite observations of 95 of Earth’s most active volcanoes since 2000.

In terms of total energy radiated, the prize goes to Hawaii’s Kilauea(shown above), which has been spilling lava continuously throughout the study period.  Thanks to its lava lake, Nyiragongo (Democratic Republic of Congo) came in a close second.  Africa’s most active volcano — and Nyiragongo’s neighbor — Nyamuragira came in third for overall energy radiated. For a full ranking of all 95 volcanoes, see the chart at the bottom of the bottom of this page. Note that the volcanoes emitting the most heat do not necessarily emit it explosively. In fact, most of the top heat producers were shield volcanoesthat released mafic lava slowly.

If you ignore the steady, continuous heat produced by volcanoes and look simply at the “extra” heat produced during eruptions, then the rankings look different. Iceland’s ongoing Holuhraun eruption has radiated the most heat for an event. At the time that the study was published, Holuhraun had radiated about one-third more thermal energy than the 2012-2013 eruption of Russia’s Tolbachik, which itself radiated about 50 percent more energy than the 2011-2012 eruption of Nyamuragira.

The study, led by Robert Wright of the Hawaii Institute of Geophysics and Planetology, was based on data acquired by the Moderate Resolution Imaging Spectroradiometers on NASA’s Aqua and Terra satellites. 

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End of cancer-genome project prompts to rethink: Should effort switch from sequencing to functional analysis?

End of cancer-genome project prompts to rethink: Should effort switch from sequencing to functional analysis? | Amazing Science |

A mammoth US effort to genetically profile 10,000 tumors has officially come to an end. Started in 2006 as a US$100-million pilot, The Cancer Genome Atlas (TCGA) is now the biggest component of the International Cancer Genome Consortium, a collaboration of scientists from 16 nations that has discovered nearly 10 million cancer-related mutations.

The question is what to do next. Some researchers want to continue the focus on sequencing; others would rather expand their work to explore how the mutations that have been identified influence the development and progression of cancer.

“TCGA should be completed and declared a victory,” says Bruce Stillman, president of Cold Spring Harbor Laboratory in New York. “There will always be new mutations found that are associated with a particular cancer. The question is: what is the cost–benefit ratio?”

Stillman was an early advocate for the project, even as some researchers feared that it would drain funds away from individual grants. Initially a three-year project, it was extended for five more years. In 2009, it received an additional $100 million from the US National Institutes of Health plus $175 million from stimulus funding that was intended to spur the US economy during the global economic recession.

On 2 December, Staudt announced that once TCGA is completed, the NCI will continue to intensively sequence tumours in three cancers: ovarian, colorectal and lung adenocarcinoma. It then plans to evaluate the fruits of this extra effort before deciding whether to add back more cancers. But this time around, the studies will be able to incorporate detailed clinical information about the patient’s health, treatment history and response to therapies. Because researchers can now use paraffin-embedded samples, they can tap into data from past clinical trials, and study how mutations affect a patient’s prognosis and response to treatment. Staudt says that the NCI will be announcing a call for proposals to sequence samples taken during clinical trials using the methods and analysis pipelines established by the TCGA.

The rest of the International Cancer Gene Consortium, slated to release early plans for a second wave of projects in February, will probably take a similar tack, says co-founder Tom Hudson, president of the Ontario Institute for Cancer Research in Toronto, Canada. A focus on finding sequences that make a tumour responsive to therapy has already been embraced by government funders in several countries eager to rein in health-care costs, he says. “Cancer therapies are very expensive. It’s a priority for us to address which patients would respond to an expensive drug.”

The NCI is also backing the creation of a repository for data not only from its own projects, but also from international efforts. This is intended to bring data access and analysis tools to a wider swathe of researchers, says Staudt. At present, the cancer genomics data constitute about 20 petabytes (10**15 bytes), and are so large and unwieldy that only institutions with significant computing power can access them. Even then, it can take four months just to download them.

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Ebola In The Air: What Science Says About How The Virus Spreads

Ebola In The Air: What Science Says About How The Virus Spreads | Amazing Science |

Turns out, Ebola is transmitted through the air, but it's not very good at spreading through the airborne route. What in the heck does that mean?

Viruses can spread through the air in two ways: inside large droplets that fall quickly to the ground (red), or inside tiny droplets that float in the air (gray). In the first route, called droplet transmission, the virus can spread only about 3 to 6 feet from an infected person. In the second route, called airborne transmission, the virus can travel 30 feet or more.

Viruses that move through the second route — the airborne route — can travel more than 30 feet and can stay in the air for minutes, even hours, when the humidity and temperature are right. That means you don't even have to see the person to catch a virus from him or her. An infected person could sneeze, walk out of the room and leave an infectious mist behind.

A few viruses, such as measles and chickenpox, spread this way (that's why they have such high R0s). What about Ebola? In the lab, scientists can infect monkeys with Ebola virus through the airborne route. They essentially stick a monkey's head in a plastic tube and spray the animal's face with a mist infused with Ebola. If the humidity and temperature are right in the tube, the monkey can get Ebola. But scientists haven't found evidence that Ebola spreads through the airborne route in real outbreaks, with real people. Does that mean Ebola never catches a ride on tiny, floating droplets? No.

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Princeton Scientists Build Rice-Sized Laser That Bodes Well for Quantum Computing

Princeton Scientists Build Rice-Sized Laser That Bodes Well for Quantum Computing | Amazing Science |
Scientists build rice sized laser that demonstrates the interactions between light and moving electrons, and is a major step toward building quantum computing

The tiny microwave laser, or “maser,” is a demonstration of the fundamental interactions between light and moving electrons. The researchers built the device — which uses about one-billionth the electric current needed to power a hair dryer — while exploring how to use quantum dots, which are bits of semiconductor material that act like single atoms, as components for quantum computers. “It is basically as small as you can go with these single-electron devices,” said Jason Petta, an associate professor of physics at Princeton who led the study, which was published in the journal Science.

The device demonstrates a major step forward for efforts to build quantum-computing systems out of semiconductor materials, according to co-author and collaborator Jacob Taylor, an adjunct assistant professor at the Joint Quantum Institute, University of Maryland-National Institute of Standards and Technology. “I consider this to be a really important result for our long-term goal, which is entanglement between quantum bits in semiconductor-based devices,” Taylor said.

The original aim of the project was not to build a maser, but to explore how to use double quantum dots — which are two quantum dots joined together — as quantum bits, or qubits, the basic units of information in quantum computers. “The goal was to get the double quantum dots to communicate with each other,” said Yinyu Liu, a physics graduate student in Petta’s lab. The team also included graduate student Jiri Stehlik and associate research scholar Christopher Eichler in Princeton’s Department of Physics, as well as postdoctoral researcher Michael Gullans of the Joint Quantum Institute.

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House fly genome reveals an expanded immune system combatting many animal pathogens

House fly genome reveals an expanded immune system combatting many animal pathogens | Amazing Science |

Scientists have sequenced the house fly genome for the first time, revealing robust immune system genes, as one might expect from an insect that thrives in pathogen-rich dung piles and garbage heaps.

The research, published Oct. 13, 2014, in the journal Genome Biology, will increase our understanding of house fly genetics and biology and of how flies quickly adapt to resist insecticides, which could lead to novel control methods.

Adult house flies (Musca domestica) carry and transmit more than 100 human and animal diseases, including salmonellosis, anthrax, typhoid fever, tuberculosis, cholera and diarrhea as well as parasites such as pinworms, roundworms, hookworms and tapeworms. House fly larvae are important animal waste decomposers and live in close contact with many animal pathogens.

“Anything that comes out of an animal, such as bacteria and viruses, house flies can take from that waste and deposit on your sandwich,” said Jeff Scott, the paper’s lead author and a Cornell professor of entomology. “House flies are the movers of any disgusting pathogenic microorganism you can think of,” Scott added.

The genome, roughly twice the size of the fruit fly’s genome, revealed an expanded number of immune response and defense genes. The researchers also discovered an expansion in the number of cytochrome P450s, which help the flies metabolize environmental toxins. “House flies have a lot more of these enzymes than would be expected based on other insects they are related to,” said Scott, noting that the house fly’s close relative, Glossina morsitans (tsetse fly), has half as many cytochrome P450s. These enzymes are more ancient than insecticides. “We don’t have a clear handle on why house flies need so many,” Scott said.

The M. domestica genome also revealed many genes for chemoreceptors, which detect certain chemical stimuli in the environment. These receptors are important in sensing food and moving in ways critical for survival, allowing house flies to detect a wide variety of different things, Scott said.

“If you think of the genome like a phone book, we now have the phone number of every gene,” said Scott. “We now can study every gene. For any scientific question, we have a highway to get us there.”

One of those questions will focus on controlling house flies and developing new toxins that disrupt the fly’s internal balance by poisoning them or using RNAi to turn off specific genes and killing them, Scott said.

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SN1006: Many times brighter than Venus and visible during the day - the story of a supernova

SN1006: Many times brighter than Venus and visible during the day - the story of a supernova | Amazing Science |

Very detailed new observations with ESO’s Very Large Telescope (VLT) of the remains of a thousand-year-old supernova have revealed clues to the origins of cosmic rays. For the first time the observations suggest the presence of fast-moving particles in the supernova remnant that could be the precursors of such cosmic rays.

In the year 1006 a new star was seen in the southern skies and widely recorded around the world. It was many times brighter than the planet Venus and may even have rivaled the brightness of the Moon. It was so bright at maximum that it cast shadows and it was visible during the day. More recently astronomers have identified the site of this supernova and named it SN 1006. They have also found a glowing and expanding ring of material in the southern constellation of Lupus (The Wolf) that constitutes the remains of the vast explosion.

It has long been suspected that such supernova remnants may also be where some cosmic rays — very high energy particles originating outside the Solar System and travelling at close to the speed of light — are formed. But until now the details of how this might happen have been a long-standing mystery.

A team of astronomers led by Sladjana Nikolić (Max Planck Institute for Astronomy, Heidelberg, Germany) has now used the VIMOS instrument on the VLT to look at the one-thousand-year-old SN 1006 remnant in more detail than ever before. They wanted to study what is happening where high-speed material ejected by the supernova is ploughing into the stationary interstellar matter — the shock front. This expanding high-velocity shock front is similar to the sonic boom produced by an aircraft going supersonic and is a natural candidate for a cosmic particle accelerator.

For the first time the team has not just obtained information about the shock material at one point, but also built up a map of the properties of the gas, and how these properties change across the shock front. This has provided vital clues to the mystery.

The results were a surprise — they suggest that there were many very rapidly moving protons in the gas in the shock region. While these are not the sought-for high-energy cosmic rays themselves, they could be the necessary “seed particles”, which then go on to interact with the shock front material to reach the extremely high energies required and fly off into space as cosmic rays.

Nikolić explains: “This is the first time we were able to take a detailed look at what is happening in and around a supernova shock front. We found evidence that there is a region that is being heated in just the way one would expect if there were protons carrying away energy from directly behind the shock front.”

The study was the first to use an integral field spectrograph to probe the properties of the shock fronts of supernova remnants in such detail. The team now is keen to apply this method to other remnants.

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Wireless technology more than 10 times faster than the best Wi-Fi is coming to market in 2015

Wireless technology more than 10 times faster than the best Wi-Fi is coming to market in 2015 | Amazing Science |

Smartphones, tablets and PCs should appear this year that can send and receive data wirelessly more than 10 times faster than a Wi-Fi connection. As well as transferring videos and other large files in a flash, this could do away with the cables used to hook PCs up to displays or projectors.

The wireless technology that will allow this is known as 60 gigahertz—after the radio frequency it uses—and by the name “WiGig.” Computing giants including Apple, Microsoft, and Sony have quietly collaborated on the new standard for years, and a handful of products featuring WiGig are already available. But the technology will get a big push this year, with several companies bringing products featuring WiGig to market.

WiGig carries data much faster than Wi-Fi because its higher frequency radio signal can be used to encode more information. The maximum speed of a wireless channel using the current 60 gigahertz protocol is seven gigabits per second (in perfect conditions). That compares to the 433 megabits per second possible via a single channel made using the most advanced Wi-Fi protocol in use today, which transmits at five megahertz. Most Wi-Fi networks use less advanced technology that operates even slower.

Qualcomm, a leading maker of mobile device processors and wireless chips, has invested heavily in WiGig. At the International Consumer Electronics Show in Las Vegas this month, the company demonstrated a wireless router for home or office use with the technology built in. That device will go on sale by the end of 2015.

Qualcomm has also designed the latest in its line of Snapdragon mobile processors to support WiGig. The “reference designs” Qualcomm shows to customers include its 60-gigahertz wireless chips, and the first devices built using the Snapdragon 810 processor are expected to go on sale in mid-2015. At CES, Qualcomm showed tablets built with that processor using WiGig to transfer video.

Those working on WiGig technology predict that demand for high definition video will make the technology necessary. The latest smartphones now record video at extremely high resolution. Grodzinsky says WiGig will start appearing in set-top boxes, making it easier to stream content from mobile devices to high definition TVs, or upload it to the Internet. Qualcomm calculates that its WiGig technology will make it possible to transfer a full-length HD movie in just three minutes.

Besides Qualcomm, Intel is preparing its own WiGig technology, and the company said at its annual developer conference last summer that WiGig chips would appear in laptops in 2015. In demos then and at CES this month, Intel showed a laptop using WiGig to connect with displays and other peripheral devices.

Samsung also expects to launch WiGig products this year. The company announced late in 2014 that it had developed its own implementation, and said it expected to commercialize it in 2015. The technology will appear in Samsung’s mobile, health-care, and smart home products.

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Humans have crossed two of the nine "planetary boundaries" that must remain to be safe on Earth

Humans have crossed two of the nine "planetary boundaries" that must remain to be safe on Earth | Amazing Science |

The Earth’s climate has always changed. All species eventually become extinct. But a new study has brought into sharp relief the fact that humans have, in the context of geological timescales, produced near instantaneous planetary-scale disruption. We are sowing the seeds of havoc on the Earth, it suggests, and the time is fast approaching when we will reap this harvest.

This in the year that the UN climate change circus will pitch its tents in Paris. December’s Conference of the Parties will be the first time individual nations submit their proposals for their carbon emission reduction targets. Sparks are sure to fly.

The research, published in the journal Science, should focus the minds of delegates and their nations as it lays out in authoritative fashion how far we are driving the climate and other vital Earth systems beyond any safe operating space. The paper, headed by Will Steffen of the Australian National University and Stockholm Resilience Center, concludes that our industrialised civilisation is driving a number of key planetary processes into areas of high risk.

It argues climate change along with “biodiversity integrity” should be recognised as core elements of the Earth system. These are two of nine planetary boundaries that we must remain within if we are to avoid undermining the biophysical systems our species depends upon.

The original planetary boundaries were conceived in 2009 by a team lead by Johan Rockstrom, also of the Stockholm Resilience Center. Together with his co-authors, Rockstrom produced a list of nine human-driven changes to the Earth’s system: climate change, ocean acidification, stratospheric ozone depletion, alteration of nitrogen and phosphorus cycling, freshwater consumption, land use change, biodiversity loss, aerosol and chemical pollution. Each of these nine, if driven hard enough, could alter the planet to the point where it becomes a much less hospitable place on which to live.

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Huygens: Ten Years of Titan

Huygens: Ten Years of Titan | Amazing Science |

Ten years ago today—Jan. 15, 2005—humanity reached out and touched another world. It was Titan, the largest moon of Saturn. The Cassini spacecraft, still on its way to entering orbit around the ringed planet, had already dropped a small probe named Huygens—named after Dutch astronomer Christiaan Huygens, who discovered Titan—to go their separate ways. Huygens was aimed at the monster moon (bigger than the planet Mercury!), and on Jan. 5, 2005 began its descent.

Titan’s atmosphere is mostly nitrogen and twice as thick as Earth’s, so Huygens used that to slow initially, then used parachutes to drop safely down to the surface. While it did, it took a lot of photos and other data to investigate the alien world. Finally, after more than two hours, it touched down, the first time a space probe had ever successfully landed on the moon of another planet. On the YouTube channel The Mars Underground there’s a fantastic and compelling video of the descent, loaded with info, which shows you the Huygen’s-eye view of Titan as it made its way down to the surface.

Amazing! You can see the angle and size of Huygens on the left, its descent angle on the bottom left, and various data on the right. In the middle the view fills in as the camera takes its shots, and then at about 1:00 things start to pick up as the probe descends through the thick haze layer into more transparent air, close enough to see detail in the landscape which changes as the probe descends.

The sounds coming from the left speaker represent the rotation and descent angle of the probe among other things, and sounds from the right speaker represent various instruments taking data, as well as how solid the uplink connection is to Cassini (which acted as a receiver, then sending the Huygens data back to Earth). The show notes on the YouTube page have the details. But it was peculiar and sad to hear the uplink tone die as communications with Cassini were lost when the spacecraft set in Titan's sky as seen by Huygens.

In the decade since we’ve learned so much about this planet-sized moon! It has grains of hydrocarbon ice that blow in the wind, forming dunes, it has lakes of liquid methane and ethane (with features in the lakes that change with time), it has weather. It has a methane cycle, which is the analog to the water cycle on Earth; river channels are clearly seen leading downhill to flatter surfaces. And while it may be frigidly cold there to us—180 below 0 Celsius—for methane that’s near the triple point where it can be a solid, liquid, and gas, just like water on Earth.

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Water-soluble silicon leads to dissolvable electronics

Water-soluble silicon leads to dissolvable electronics | Amazing Science |

Researchers working in a materials science lab are literally watching their work disappear before their eyes—but intentionally so. They're developing water-soluble integrated circuits that dissolve in water or biofluids in months, weeks, or even a few days. This technology, called transient electronics, could have applications for biomedical implants, zero-waste sensors, and many other semiconductor devices.

The researchers, led by John A. Rogers at the University of Illinois at Urbana-Champaign and Fiorenzo Omenetto at Tufts University, have published a study in a recent issue of Applied Physics Letters in which they analyzed the performance and dissolution times of various semiconductor materials.

The work builds on previous research, by the authors and others, which demonstrated that silicon—the most commonly used semiconductor material in today's electronic devices—can dissolve in water. Although it would take centuries to dissolve bulk silicon, thin layers of silicon can dissolve in more reasonable times at low but significant rates of 5-90 nm/day. The silicon dissolves due to hydrolysis, in which water and silicon react to form silicic acid. Silicic acid is environmentally and biologically benign.

In the new study, the researchers analyzed the dissolution characteristics of silicon dioxide and tungsten, which they used to fabricate two electronics devices: field-effect transistors and ring oscillators. Under biocompatible conditions (37 °C, 7.4 pH), dissolution rates ranged from 1 week for the tungsten components, to between 3 months and 3 years for the silicon dioxide components. The dissolution rates can be controlled by several factors, such as the thickness of the materials, the concentration and type of ions in the solution, and the method used to deposit the silicon dioxide on the original substrate.

As shown in the microscope images, the circuits do not dissolve in a uniform, layer-by-layer mode, but instead some places dissolve more rapidly than others. This is due to mechanical fractures in the fragile circuits, which cause the solution to penetrate through the layers more in some locations than in others. Although organic electronic materials are also often biodegradable, silicon-based electronics have the advantages of an overall higher performance and the use of complementary metal-oxide-semiconductor (CMOS) fabrication processes that allow for mass-production.

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Squid uses luminescent bacteria to match moonlight welling down from above to cancel out its own shadow

Squid uses luminescent bacteria to match moonlight welling down from above to cancel out its own shadow | Amazing Science |

The aquarium looks empty, but there is something in it. A pair of eyes stick out from the sandy floor, and their owner is easily scooped up into a glass bowl. At first, the creature looks like a hazelnut truffle — small, round and covered in tiny flecks. But with a gentle shake, the flecks of sand fall off to reveal a female Hawaiian bobtail squid (Euprymna scolopes), about the size of a thumb. As she jets furiously around the bowl, discs of pigment bloom and fade over her skin like a living pointillist painting.

There are no other animals in the bowl, but the squid is not alone. Its undersides contain a two-chambered light organ that is full of glowing bacteria called Vibrio fischeri. In the wild, their luminescence is thought to match the moonlight welling down from above and cancel out the squid's shadow, hiding the animal from predators. From below, the squid is invisible. From above, it is adorable. “They're just so beautiful,” says Margaret McFall-Ngai, a zoologist at the University of Wisconsin–Madison. “They're phenomenal lab animals.”

Few things excite McFall-Ngai more than the partnership between the bobtail squid and V. fischeri — and that is after studying it for more than 26 years. Over that time, she has shown that this symbiotic relationship is more intimate than anyone had imagined. She has found that the bacterium out-competes other microbes to establish an entirely faithful relationship with one host. It interacts with the squid's immune system, guides its body clock and shapes its early development by transforming its body.

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Hibernation hints at novel dementia and Alzheimer's therapy

Hibernation hints at novel dementia and Alzheimer's therapy | Amazing Science |

Bears, hedgehogs and mice destroy brain connections as they enter hibernation, and repair them as they wake up. A team of scientists now discovered "cold-shock chemicals" that trigger the process. They used theses to prevent brain cells dying in animals, and say that restoring lost memories may eventually be possible.

Experts have described the findings as "promising" and "exciting". In the early stages of Alzheimer's, and other neurodegenerative disorders, synapses are lost. This inevitably progresses to whole brain cells dying. But during hibernation, 20-30% of the connections in the brain - synapses - are culled as the body preserves precious resources over winter. And remarkably those connections are reformed in the spring, with no loss of memory.

In experiments, non-hibernating mice with Alzheimer's disease and prion disease were cooled so their body temperature dropped from 37˚C to 16-18˚C. Young diseased mice lost synapses during the chill and regained them as they warmed up. Old mice also lost brain connections, but were unable to re-establish them. The study, published in the journal Nature, found levels of a "cold-shock" chemical called RBM3 soared when young mice were chilled, but not in old mice. It suggested RBM3 was key to the formation of new connections.

In a further set of tests, the team showed the brain cell deaths from prion disease and Alzheimer's could be prevented by artificially boosting RBM3 levels. The discovery comes from the laboratory that was the first to prevent the death of brain tissue in a neurodegenerative disease.

Dr Doug Brown, the director of research and development at the Alzheimer's Society said: "We know that cooling body temperate can protect the brain from some forms of damage and it's interesting to see this protective mechanism now also being studied in neurodegenerative disease. "Connections between brain cells - called synapses - are lost early on in several neurodegenerative conditions, and this exciting study has shown for the first time that switching on a cold-shock protein called RBM3 can prevent these losses.

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DNA does design: 3D plasmonic photonic crystallization of DNA-guided colloidal crystals

DNA does design: 3D plasmonic photonic crystallization of DNA-guided colloidal crystals | Amazing Science |

As biotechnology and nanotechnology continue to merge, DNA-programmable methods have emerged as a way to provide unprecedented control over the assembly of nanoparticles into complex structures, including customizable periodic structures known as superlattices that allow fine tuning the interaction between light and highly organized collections of particles. Lattice structures have historically been two-dimensional because fabricating three-dimensional DNA lattices has been too difficult, while three-dimensional dielectric photonic crystals have well-established enhanced light–matter interactions. However, the dearth of synthetic means of creating plasmonic crystals (those that exploit surface plasmons produced from the interaction of light with metal-dielectric materials) based on arrays of nanoparticles has prevented them from being experimentally studied. At the same time, it has been suggested that polaritonic photonic crystals (PPCs) – plasmonic counterparts of photonic crystals – can prohibit light propagation and open a photonic band gap (also known as a polariton gap) by strong coupling between surface plasmons and photonic modes if the crystal is in a deep subwavelength size regime. Polaritons are quasiparticles resulting from strong coupling of electromagnetic waves with an electric or magnetic dipole-carrying excitation.

To that end, scientists at Northwestern University recently reported strong light-plasmon interactions within 3D plasmonic photonic crystals that have lattice constants and nanoparticle diameters that can be independently controlled in the deep subwavelength size regime by using a DNA-programmable assembly technique – the first devices prepared by DNA-guided colloidal crystallization. The researchers have shown that they can tune the interaction between light and the collective electronic modes of gold nanoparticles by independently adjusting lattice constants and gold nanoparticle diameters, adding that their results in tuning interactions between light and highly-organized nanoscale collections of particles suggest the possibility of applications that include lasers, quantum electrodynamics and biosensing.

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