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Super-massive black hole with a mass half the size of its hosting galaxy

Super-massive black hole with a mass half the size of its hosting galaxy | Amazing Science | Scoop.it

A new survey recently reported in Nature found a supermassive black hole (mass~17 billions of solar masses) at the center of a relatively "light" galaxy. This wouldn't be a surprise if the mass of the black hole wasn't more than half the mass of the buldge of the hosting galaxy. The black line shows the mass–luminosity relation for galaxies with a directly measured black-hole mass.

 

NGC 1277 is a significant positive outlier. Indeed, we already know that most galaxies -- including our own Milky Way -- host supermassive black holes which lurk at the galactic center. Also, the mass of the black hole is believed to be tightly connected with the properties of the hosting galaxy. Several models of galaxy dynamics and mergers predict a black hole mass VS bulge luminosity relation similar to that shown in the Figure above and this has important implications in the understanding of the galaxy evolution and of black hole population models. Typically, the mass of the black hole is about 0.1 per cent of the mass of the stellar bulge of the galaxy and the maximum mass fraction observed so far was about 10%.

 

The discovery of NGC 1277, a compact, lenticular galaxy with a mass of roughly 1.2x10^11 solar masses, is particularly interesting because this galaxy hosts a black hole of mass about 1.7x10^10 solar masses, that is, roughly 59% of the total bulge mass. Indeed, it's evident in the Figure above how NGC 1277 deviates from the expected empirical behavior.

 

This discovery seems confirmed by other observations of galaxies that host oversized black holes and it might suggest a failure (or the need of some improvement) in current models.

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How specialized enzymes remodel condensed chromatin in order to control genes

How specialized enzymes remodel condensed chromatin in order to control genes | Amazing Science | Scoop.it

An international team of biologists has discovered how specialized enzymes remodel the extremely condensed genetic material in the nucleus of cells in order to control which genes can be used. The discovery will be published in the print edition of the journal Nature on Feb. 4, 2016.


It was known that the DNA in cells is wrapped around proteins in structures called nucleosomes that resemble beads on a string, which allow the genetic material to be folded and compacted into a structure called chromatin. "We knew that the compaction into chromatin makes genes inaccessible to the cellular machinery necessary for gene expression, and we also knew that enzymes opened up the chromatin to specify which genes were accessible and could be expressed in a cell, but until now, we didn't know the mechanism by which these enzymes functioned," said B. Franklin Pugh, Evan Pugh Professor, Willaman Chair in Molecular Biology, and professor of biochemistry and molecular biology at Penn State University and one of the two corresponding authors of the paper along with Matthieu Gérard of the University of Paris-Sud in France.


The discovery was achieved by an international collaboration of scientists from the Alternative Energies and Atomic Energy Commission in France (Commissariat à l'énergie atomique et aux énergies alternatives), the National Center for Scientific Research in France (Centre national de la recherche scientifique), the University of Paris-Sud in France, Southern Medical University in Guangzhou in China, and Penn State University in the United States.


The researchers first mapped the location of several "chromatin-remodeller enzymes" across the entire genome of the embryonic stem cells of the mouse. The mapping showed that remodeller enzymes bind to particular nucleosomes "beads" at the sites along the wrapped-up DNA that are located just before the gene sequence begins. These sites are important because they are the location where the process of expressing genes begins -- where other proteins required for gene expression team up for the process of turning a gene on.


The researchers then tested how the chromatin-remodeller enzymes impact gene expression by reducing the amount of each of these enzymes in embryonic stem cells. The scientists found that some chromatin-remodeller enzymes promote gene expression, some repress gene expression, and some can do both.


"The correct expression of genes is necessary to define the identity and function of different types of cells in the course of embryonic development and adult life," said Pugh. "Chromatin-remodeller enzymes help each cell type accurately express the proper set of genes by allowing or blocking access to the critical section of DNA at the beginning of genes."


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Evidence that life once existed on Mars may have been discovered, scientists suggest

Evidence that life once existed on Mars may have been discovered, scientists suggest | Amazing Science | Scoop.it

Unusual silica formations spotted by a NASA rover look a lot like structures formed by microbes around geysers on Earth.


The hunt for signs of life on Mars has been on for decades, and so far scientists have found only barren dirt and rocks. Now a pair of astronomers thinks that strangely shaped minerals inside a Martian crater could be the clue everyone has been waiting for.


In 2008, scientists announced that NASA’s Spirit rover had discovered deposits of a mineral called opaline silica inside Mars's Gusev crater. That on its own is not as noteworthy as the silica’s shape: Its outer layers are covered in tiny nodules that look like heads of cauliflower sprouting from the red dirt.


No one knows for sure how those shapes—affectionately called “micro-digitate silica protrusions”—formed. But based on recent discoveries in a Chilean desert, Steven Ruff and Jack Farmer, both of Arizona State University in Tempe, think the silica might have been sculpted by microbes. At a meeting of the American Geophysical Union in December, they made the case that these weird minerals might be our best targets for identifying evidence of past life on Mars.


If the logic holds, the silica cauliflower could go down in history as arguably the biggest discovery ever in astronomy. But biology is hard to prove, especially from millions of miles away, and Ruff and Farmer aren’t claiming victory yet. All they’re saying is that maybe these enigmatic growths are mineral greetings from ancient aliens, and someone should investigate.


Spirit found the silica protrusions near the “Home Plate” region of Gusev crater, where geologists think hot springs or geysers once scorched the red planet's surface. To understand what that long-dormant landscape used to be like, we have to look closer to home: hydrothermal regions of modern Earth that resemble Mars in its ancient past.


To that end, Ruff has twice in the past year trekked to Chile’s Atacama Desert, a high plateau west of the Andes cited as the driest non-polar place on Earth. Scientists often compare this desert to Mars, and not just poetically. It’s actually like Mars. The soil is similar, as is the extreme desert climate.


In this part of the Atacama, it rains less than 100 millimeters per year, and temperatures swing from -13°F to 113°F. With an average elevation of 13,000 feet above sea level, lots of ultraviolet radiation makes it through the thin atmosphere to the ground, akin to the punishing radiation that reaches the surface of Mars.


Just as we interpret others’ behavior and emotions by peering into our own psychology, scientists look around our planet to help them interpret Mars, find its most habitable spots and look for signs of life. While the Atacama does have breathable oxygen and evolutionarily clever foxes (which Mars does not), its environment mimics Mars’s pretty well and makes a good standin for what the red planet may have been like when it was warmer and wetter.


So when geologists see something in the Atacama or another Mars analog that matches a feature on the red planet, they reasonably conclude that the two could have formed the same way. It’s not a perfect method, but it’s the best we’ve got. “I don't think there is any way around using modern Earth analogs to test where Martian microbes may be found,” says Kurt Konhauser of the University of Alberta, who is the editor-in-chief of the journal Geobiology.


But the comparison goes further: When Ruff peered closely at El Tatio’s silica formations, he saw shapes remarkably similar to those that Spirit had seen on Mars. Fraternal cauliflower twins also exist in Yellowstone National Park in Wyoming and the Taupo Volcanic Zone in New Zealand. In both of those places, the silica bears the fossilized fingerprints of microbial life.


Since microbes sculpted the silica features in Wyoming and New Zealand, it's possible they also helped make the formations at El Tatio. And if microbes were involved with the cauliflower at El Tatio, maybe they made it grow on Mars, too.

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Same Switches Program Taste and Smell in Fruit Flies

Same Switches Program Taste and Smell in Fruit Flies | Amazing Science | Scoop.it

A new study sheds light on how fruit flies get their keen sense of smell.

Duke University biologist Pelin Volkan and colleagues have identified a set of genetic control switches that interact early in a fly’s development to generate dozens of types of olfactory neurons, specialized nerve cells for smell. 


The same gene network also plays a role in programming the fly neurons responsible for taste, the researchers report in the journal PLOS Genetics.

The findings do more than merely explain how a household pest distinguishes rotting vegetables from ripening fruit, the authors say. The research could be a key to understanding how the nervous systems of other animals -- including humans, whose brains have billions of neurons -- produce such a dazzling array of cell types from a modest number of genes.


Fruit flies rely on their keen sense of smell to tell the difference between good food and bad, safety and danger, potential mates and those off-limits. The tiny insects perceive this wide range of chemical cues through a diverse set of olfactory sensory neurons along their antennae. More than 2000 such neurons are organized into 50 types, each of which transmits information to a specific region of the fly’s poppy seed-sized brain.


“Each neuron type detects a very specific range of odors,” Volkan said. Certain odors from fermenting fruit, for example, activate one class of neurons, and carbon dioxide activates another.


Volkan is interested in how the many types of smell neurons come to be as a fruit fly develops from egg to an adult.  Smell neurons begin as identical precursor cells, immature cells that have not yet “decided” which type of nerve cell they will become. All precursor cells have the same DNA, and how they produce one neuron type versus another was unknown.


One way to get many types of cells or proteins from the same genetic starting material is by mixing and matching different parts of one gene to produce multiple gene readouts, a phenomenon known as alternative splicing. The team’s results point to another strategy, however: using the same genes in different combinations, or “combinatorial coding.”


By tweaking different fly genes and counting how many neuron types were produced as the flies matured, the team identified a network of five genes that work together like coordinated control switches to guide the precursor cells’ transformation to mature neurons. The genes regulate each other’s activity, interacting in unique combinations to set each precursor cell on a distinct path by turning on different olfactory receptors in each cell.


The researchers found that manipulating the network had similar effects in the legs, which flies use not only to walk but also to taste. “The same basic toolkit gives rise to diverse types of neurons in completely different tissues,” said Volkan, who is also a member of the Duke Institute for Brain Sciences.


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Researchers Create Smallest Ever Lattice Structure

Researchers Create Smallest Ever Lattice Structure | Amazing Science | Scoop.it
A team of scientists at the Karlsruhe Institute of Technology, Germany, has created a glassy carbon nanolattice with single struts shorter than 1 μm and diameters as small as 200 nm -- the smallest lattice structure yet produced.


The world’s smallest lattice is visible under the microscope only, according to the team, led by Dr. Jens Bauer. “The smallest stable lattice structure presented now was produced by the established 3D laser lithography process at first,” said Dr. Bauer, who is the lead author of a paper published online yesterday in the journal Nature Materials.


For their experiments, Dr. Bauer and his colleagues manufactured three differently sized lattices with tetrahedral unit cells with edge or strut lengths of 10, 7.5 and 5 µm. In the subsequent pyrolysis step, these polymeric microlattices were converted into carbon nanostructures in a furnace. “The objects were exposed to temperatures of around 1,650 degrees Fahrenheit (900 degrees Celsius) in a vacuum tube furnace,” Dr. Bauer and co-authors explained.


“During the pyrolysis, the unit cell sizes of our structures shrank by roughly 80% compared to the initially fabricated sizes, yielding lattices with unit cell edge lengths of 2,020 nm, 1,440nm and 970 nm, respectively.”


“The struts of the pyrolyzed lattices have elliptical cross-sections with axial diameters of 330, 270 and 225 nm and lateral diameters of 275, 235 and 205 nm, respectively, for the three different lattice sizes.”


The resulting structures were tested for stability under pressure by the researchers. “According to the results, load-bearing capacity of the lattice is very close to the theoretical limit and far above that of unstructured glassy carbon,” said team member Prof. Oliver Kraft.


“The strength-to-density ratios of the nanolattices are 6 times higher than those of reported microlattices. With a honeycomb topology, effective strengths of 1.2 GPa at 0.6 g/cm3 are achieved,” the scientists said.


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No more insulin injections? Encapsulated pancreatic cells offer new possibilities

No more insulin injections? Encapsulated pancreatic cells offer new possibilities | Amazing Science | Scoop.it
Researchers have designed a material that prevents transplanted human islet cells from being attacked by the immune system in patients with Type 1 diabetes. The advance could help patients control their blood sugar without taking drugs.


Since the 1980s, a standard treatment for diabetic patients has been injections of insulin produced by genetically engineered bacteria. While effective, this type of treatment requires great effort by the patient and can generate large swings in blood sugar levels.


At the urging of JDRF director Julia Greenstein, Anderson, Langer, and colleagues set out several years ago to come up with a way to make encapsulated islet cell transplantation a viable therapeutic approach. They began by exploring chemical derivatives of alginate, a material originally isolated from brown algae. Alginate gels can be made to encapsulate cells without harming them, and also allow molecules such as sugar and proteins to move through, making it possible for cells inside to sense and respond to biological signals.


However, previous research has shown that when alginate capsules are implanted in primates and humans, scar tissue eventually builds up around the capsules, making the devices ineffective. The MIT/Children’s Hospital team decided to try to modify alginate to make it less likely to provoke this kind of immune response.


“We decided to take an approach where you cast a very wide net and see what you can catch,” says Arturo Vegas, a former MIT and Boston Children’s Hospital postdoc who is now an assistant professor at Boston University. Vegas is the first author of the Nature Biotechnology paper and co-first author of the Nature Medicine paper.


“We made all these derivatives of alginate by attaching different small molecules to the polymer chain, in hopes that these small molecule modifications would somehow give it the ability to prevent recognition by the immune system.”


After creating a library of nearly 800 alginate derivatives, the researchers performed several rounds of tests in mice and nonhuman primates. One of the best of those, known as triazole-thiomorpholine dioxide (TMTD), they decided to study further in tests of diabetic mice. They chose a strain of mice with a strong immune system and implanted human islet cells encapsulated in TMTD into a region of the abdominal cavity known as the intraperitoneal space.


The pancreatic islet cells used in this study were generated from human stem cells using a technique recently developed by Douglas Melton, a professor at Harvard University who is an author of the Nature Medicine paper. Following implantation, the cells immediately began producing insulin in response to blood sugar levels and were able to keep blood sugar under control for the length of the study, 174 days.


“The really exciting part of this was being able to show, in an immune-competent mouse, that when encapsulated these cells do survive for a long period of time, at least six months,” says Omid Veiseh, a senior postdoc at the Koch Institute and Boston Children’s hospital, co-first author of the Nature Medicine paper, and an author of the Nature Biotechnology paper. “The cells can sense glucose and secrete insulin in a controlled manner, alleviating the mice’s need for injected insulin.”

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Antarctic fungi survive Martian conditions on the International Space Station

Antarctic fungi survive Martian conditions on the International Space Station | Amazing Science | Scoop.it

European scientists have gathered tiny fungi that take shelter in Antarctic rocks and sent them to the International Space Station. After 18 months on board in conditions similar to those on Mars, more than 60% of their cells remained intact, with stable DNA. The results provide new information for the search for life on the red planet. Lichens from the Sierra de Gredos (Spain) and the Alps (Austria) also travelled into space for the same experiment.


The McMurdo Dry Valleys, located in the Antarctic Victoria Land, are considered to be the most similar earthly equivalent to Mars. They make up one of the driest and most hostile environments on our planet, where strong winds scour away even snow and ice. Only so-called cryptoendolithic microorganisms, capable of surviving in cracks in rocks, and certain lichens can withstand such harsh climatological conditions.


A few years ago a team of European researchers travelled to these remote valleys to collect samples of two species of cryptoendolithic fungi: Cryomyces antarcticus and Cryomyces minteri. The aim was to send them to the International Space Station (ISS) for them to be subjected to Martian conditions and space to observe their responses.


The tiny fungi were placed in cells (1.4 centimeters in diameter) on a platform for experiments known as EXPOSE-E, developed by the European Space Agency to withstand extreme environments. The platform was sent in the Space Shuttle Atlantis to the ISS and placed outside the Columbus module with the help of an astronaut from the team led by Belgian Frank de Winne.


For 18 months half of the Antarctic fungi were exposed to Mars-like conditions. More specifically, this is an atmosphere with 95% CO2, 1.6% argon, 0.15% oxygen, 2.7% nitrogen and 370 parts per million of H2O; and a pressure of 1,000 pascals. Through optical filters, samples were subjected to ultra-violet radiation as if on Mars (higher than 200 nanometers) and others to lower radiation, including separate control samples.


“The most relevant outcome was that more than 60% of the cells of the endolithic communities studied remained intact after ‘exposure to Mars’, or rather, the stability of their cellular DNA was still high,” highlights Rosa de la Torre Noetzel from Spain’s National Institute of Aerospace Technology (INTA), co-researcher on the project.


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Mining social media can help improve disaster response efforts

Mining social media can help improve disaster response efforts | Amazing Science | Scoop.it

Leveraging publicly available social media posts could help disaster response agencies quickly identify impacted areas in need of assistance, according to a Penn State-led team of researchers. By analyzing the September 2013 Colorado floods, researchers showed that a combination of remote sensing, Twitter and Flickr data could be used to identify flooded areas.


"FEMA (the Federal Emergency Management Agency), the Red Cross and other response agencies use social media now to disseminate relevant information to the general public," said said Guido Cervone, associate professor of geography and associate director of the Penn State's Institute for CyberScience. "We have seen here that there is potential to use social media data from community members to help identify hotspots in need of aid, especially when it is paired with remote sensing imagery of the area."


After a disaster, response teams typically prioritize rescue and aid efforts with help from imagery and other data that show what regions are affected the most. Responders commonly use satellite imagery, but this on its own has drawbacks.


"Publicly available satellite imagery for a location isn't always available in a timely manner -- sometimes it can take days before it becomes available," said Elena Sava, graduate student in geography, Penn State. "Our research focused on identifying data in non-traditional data streams that can prove mission critical for specific areas where there might be damage. We wanted to see if social media could help filling the gaps in the satellite data."


The 2013 Colorado flooding was an unprecedented event. In nine days in September, Boulder, Colo., received more than 43 centimeters, or 17 inches of rain -- nearly the amount of rainfall it normally receives in a year. Officials evacuated more than 10,000 people and had to rescue several thousand people and pets.


Because the flooding occurred in an urban setting, the researchers were able to access more than 150,000 tweets from people affected by the flooding. Using a tool called CarbonScanner, they identified clusters of posts suggesting possible locations of damage. Then, they analyzed more than 22,000 photos from the area obtained through satellites, Twitter, Flickr, the Civil Air Patrol, unmanned aerial vehicles and other sources.

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Lab-bred corals have successfully reproduced in the wild for the first time

Lab-bred corals have successfully reproduced in the wild for the first time | Amazing Science | Scoop.it

For the first time ever, lab-grown Caribbean corals have integrated with wild populations and successfully reproduced, representing the first good news we’ve heard since the world plunged itself into the third global bleaching eventin recorded history.


Scientists have predicted that the damage stemming from this event will affect 38 percent of the planet’s reefs, with 12,000 square kilometres expected to die out with the next 12 months. An estimated 80 percent of all Caribbean coralshave already disappeared over the last four decades.


In an effort to address this particularly beleagured population, scientists from the international conservation group SECORE (which stands for SExual COral REproduction) have been breeding baby corals in the lab to seed out into the wild.


"In 2011, offspring of the critically endangered elkhorn coral (Acropora palmata) were reared from gametes collected in the field and were outplanted to a reef one year later," said Valerie Chamberland, a coral reef ecologist a SECORE.


Now, just a few years later, the team is seeing the (very exciting) fruits of their labour. "In four years, these branching corals have grown to a size of a soccer ball and reproduced, simultaneously with their natural population, in September 2015," says Chamberland. "This event marks the first ever successful rearing of a threatened Caribbean coral species to its reproductive age."


Elkhorn coral is one of the most distinctive species you’ll come across, and this makes it vital to the Caribbean reef it inhabits. Its huge, branching shape - elkhorns grow 5 to 10 cm per year and often reach a diameter of 3.7 metres - not only protects the shore from storm damage, but provides a spacious home for other marine life, such as lobsters and parrotfish.


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Physicists investigate the structure of time, with implications for quantum mechanics and philosophy

Physicists investigate the structure of time, with implications for quantum mechanics and philosophy | Amazing Science | Scoop.it

Although in theory it may seem possible to divide time up into infinitely tiny intervals, the smallest physically meaningful interval of time is widely considered to be the Planck time, which is approximately 10-43 seconds. This ultimate limit means that it is not possible for two events to be separated by a time smaller than this.


But now in a new paper, physicists have proposed that the shortest physically meaningful length of time may actually be several orders of magnitude longer than the Planck time. In addition, the physicists have demonstrated that the existence of such a minimum time alters the basic equations of quantum mechanics, and as quantum mechanics describes all physical systems at a very small scale, this would change the description of all quantum mechanical systems.


The researchers, Mir Faizal at the University of Waterloo and University of Lethbridge in Canada, Mohammed M. Khalil at Alexandria University in Egypt, and Saurya Das at the University of Lethbridge, have recently published a paper called "Time crystals from minimum time uncertainty" in The European Physical Journal C.


"It might be possible that, in the universe, the minimum time scale is actually much larger than the Planck time, and this can be directly tested experimentally," Faizal explainsThe Planck time is so short that no experiment has ever come close to examining it directly—the most precise tests can access a time interval down to about 10−17 seconds.


Nevertheless, there is a great deal of theoretical support for the existence of the Planck time from various approaches to quantum gravity, such as string theory, loop quantum gravity, and perturbative quantum gravity. Almost all of these approaches suggest that it is not possible to measure a length shorter than the Planck length, and by extension not possible to measure a time shorter than the Planck time, since the Planck time is defined as the time it takes light to travel a single unit of the Planck length in a vacuum.


Motivated by several recent theoretical studies, the scientists further delved into the question of the structure of time—in particular, the long-debated question of whether time is continuous or discrete. "In our paper, we have proposed that time is discrete in nature, and we have also suggested ways to experimentally test this proposal," Faizal said.


One possible test involves measuring the rate of spontaneous emission of a hydrogen atom. The modified quantum mechanical equation predicts a slightly different rate of spontaneous emission than that predicted by the unmodified equation, within a range of uncertainty. The proposed effects may also be observable in the decay rates of particles and of unstable nuclei.


Based on their theoretical analysis of the spontaneous emission of hydrogen, the researchers estimate that the minimum time may be orders of magnitude larger than the Planck time, but no greater than a certain amount, which is fixed by previous experiments. Future experiments could lower this bound on the minimum time or determine its exact value.


The scientists also suggest that the proposed changes to the basic equations of quantum mechanics would modify the very definition of time. They explain that the structure of time can be thought of as a crystal structure, consisting of discrete, regularly repeating segments.


On a more philosophical level, the argument that time is discrete suggests that our perception of time as something that is continuously flowing is just an illusion.

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NASA engineers tapped to build first integrated-photonics modem

NASA engineers tapped to build first integrated-photonics modem | Amazing Science | Scoop.it

A NASA team has been tapped to build a new type of communications modem that will employ an emerging, potentially revolutionary technology that could transform everything from telecommunications, medical imaging, advanced manufacturing to national defense.


The space agency's first-ever integrated-photonics modem will be tested aboard the International Space Station beginning in 2020 as part of NASA's multi-year Laser Communications Relay Demonstration, or LCRD. The cell phone-sized device incorporates optics-based functions, such as lasers, switches, and wires, onto a microchip -- much like an integrated circuit found in all electronics hardware.


Once aboard the space station, the so-called Integrated LCRD LEO (Low-Earth Orbit) User Modem and Amplifier (ILLUMA) will serve as a low-Earth orbit terminal for NASA's LCRD, demonstrating yet another capability for high-speed, laser-based communications.


Since its inception in 1958, NASA has relied exclusively on radio frequency (RF)-based communications. Today, with missions demanding higher data rates than ever before, the need for LCRD has become more critical, said Don Cornwell, director of NASA's Advanced Communication and Navigation Division within the space Communications and Navigation Program, which is funding the modem's development.


LCRD promises to transform the way NASA sends and receives data, video and other information. It will use lasers to encode and transmit data at rates 10 to 100 times faster than today's communications equipment, requiring significantly less mass and power. Such a leap in technology could deliver video and high-resolution measurements from spacecraft over planets across the solar system -- permitting researchers to make detailed studies of conditions on other worlds, much as scientists today track hurricanes and other climate and environmental changes here on Earth.


The project, which is expected to begin operations in 2019, isn't NASA's first foray into laser communications. A payload aboard the Lunar Atmosphere and Dust Environment Explorer (LADEE) demonstrated record-breaking download and upload speeds to and from lunar orbit at 622 megabits per second (Mbps) and 20 Mbps, respectively, in 2013.



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A novel ’4D printing’ method inspired by plants

A novel ’4D printing’ method inspired by plants | Amazing Science | Scoop.it

Harvard University scientists have evolved their microscale 3D printing technology to the fourth dimension, time. Inspired by natural structures like plants, which respond and change their form over time according to environmental stimuli, the team has designed 4D-printed hydrogel composite structures that change shape upon immersion in water. The team is located at the Wyss Institute for Biologically Inspired Engineering at Harvard University and the Harvard John A. Paulson School of Engineering and Applied Sciences.


“This work represents an elegant advance in programmable materials assembly, made possible by a multidisciplinary approach,” said Jennifer Lewis, Sc.D., senior author of a new study reported on January 25 in a new  in Nature Materials. “We have now gone beyond integrating form and function to create transformable architectures.”


In nature, flowers and plants have tissue compositions and microstructures that result in dynamic morphologies (forms) that change according to their environments. Mimicking the variety of shape changes undergone by plant organs such as tendrils, leaves, and flowers in response to environmental stimuli like humidity and/or temperature, the 4D-printed hydrogel composites developed by Lewis and her team are programmed to contain precise, localized swelling behaviors.


The trick: the hydrogel composites contain cellulose fibrils that are derived from wood and are similar to the microstructures that enable shape changes in plants. By aligning cellulose fibrils during printing, the hydrogel composite ink is encoded with anisotropic swelling and stiffness, which can be patterned to produce intricate shape changes. The anisotropic (irregular) nature of the cellulose fibrils gives rise to varied directional properties that can be predicted and controlled. That’s why wood can be split easier along the grain rather than across it.


Likewise, when immersed in water, the hydrogel-cellulose fibril ink undergoes differential swelling behavior along and orthogonal to the printing path. Combined with a proprietary mathematical model developed by the team that predicts how a 4D object must be printed to achieve prescribed transformable shapes, the new method opens up many new and exciting potential applications for 4D printing technology including smart textiles, soft electronics, biomedical devices, and tissue engineering.


The composite ink that the team uses flows like liquid through the printhead, yet rapidly solidifies once printed. A variety of hydrogel materials can be used interchangeably resulting in different stimuli-responsive behaviors, while the cellulose fibrils can be replaced with other anisotropic fillers of choice, including conductive fillers. The mathematical model prescribes the printing pathways required to achieve the desired shape-transforming response. Specifically, it solves the “inverse problem” — the challenge of being able to predict what the printing toolpath must be to encode swelling behaviors toward achieving a specific desired target shape.


“It is wonderful to be able to design and realize, in an engineered structure, some of nature’s solutions,” said L. Mahadevan, Ph.D., a Wyss Core Faculty member as well as the Lola England de Valpine Professor of Applied Mathematics, Professor of Organismic and Evolutionary Biology, and Professor of Physics at Harvard University and Harvard SEAS, is a co-author on the study. “By solving the inverse problem, we are now able to reverse-engineer the problem and determine how to vary local inhomogeneity, i.e. the spacing between the printed ink filaments, and the anisotropy, i.e. the direction of these filaments, to control the spatiotemporal response of these shapeshifting sheets.”

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Shocking predictions for life after 2020 from Ray Kurzweil, who leads Google's AI effort

Shocking predictions for life after 2020 from Ray Kurzweil, who leads Google's AI effort | Amazing Science | Scoop.it

Ray Kurzweil is the world's foremost futurist, authoring bestsellers like "The Age of Spiritual Machines"  and "How to Create a Mind."

He's so influential that Google hired him to lead its artificial intelligence efforts.  Kurzweil is known for making predictions, which are right about 86% of the time.  Here are some of his most promising (and terrifying) visions of the 2020s and beyond.


Nanobots, Kurzweil said in a webinar earlier this year, will give us "full immersion virtual reality from within the nervous system." Earlier this month, Kurzweil said that nanobots will "finish the job" of the natural human immune system.  We'll be able to defeat any disease, even cancer. This leads to what futurists call "radical life extension." Kurzweil, like other futurists,considered death a disease to be cured — and nanobots are one of the ways to cure it.


As 3-D printing becomes more large scale and open source, more of of the world around us will become information technology. 

Kurzweil says that by the 2020s, you'll be able to "live extremely well and print out everything you need." Already, 3-D printed housesrib cages, andbridges are becoming a reality.


And we will hit singularity. The most important date for Kurzweil is 2045. That's the year, he says, of what futurists call the Singularity, the moment when biological evolution's rate of growth is superceded by artificial intelligence. Kurzweil says that in 2045, the computational power of artificial intelligence will be a billion times that of human intelligence. And our species will never be the same...


Kurzweil and other futurists see "mind-uploading" as a major consequence of the singularity. Even Stephen Hawking thinks it's possible. "I think the brain is like a program in the mind, which is like a computer, so it's theoretically possible to copy the brain on to a computer and so provide a form of life after death," the physicist says. "However, this is way beyond our present capabilities." But by 2045, it might not be.


If your mind is uploaded and virtual reality is fully immersive, then no doubt your bodywill be virtual, too. "The virtual bodies will be as detailed and convincing as real bodies," Kurzweil says.

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Marc Kneepkens's curator insight, January 30, 7:30 AM

This article will start you thinking about AI - Artificial Intelligence and how it will impact you in this lifetime.

The Asymptotic Leap's curator insight, January 30, 4:56 PM

The G-forces of asymptotic liftoff...

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Ravens might possess a Theory of Mind, say scientists

Ravens might possess a Theory of Mind, say scientists | Amazing Science | Scoop.it
A new study of ravens' behavior when they think they're being 'spied on' suggests they possess building blocks of humans' own ability to interpret others' thoughts, hopes, and fears.


Recent studies purported to demonstrate that chimpanzees, monkeys and corvids possess a basic Theory of Mind, the ability to attribute mental states like seeing to others. However, these studies remain controversial because they share a common confound: the conspecific’s line of gaze, which could serve as an associative cue. Here, we show that ravens Corvus corax take into account the visual access of others, even when they cannot see a conspecific.


Specifically, we find that ravens guard their caches against discovery in response to the sounds of conspecifics when a peephole is open but not when it is closed. Our results suggest that ravens can generalize from their own perceptual experience to infer the possibility of being seen. These findings confirm and unite previous work, providing strong evidence that ravens are more than mere behavior-readers.


Ravens do spy on each other, it turns out, and they can infer when other birds are snooping on them. New findings, released Tuesday in a study inNature Communications, highlight just how sophisticated – and human-like – ravens' cognitive abilities are.

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Cancer Spread Tracked From A Single Cell In A Live Animal

Cancer Spread Tracked From A Single Cell In A Live Animal | Amazing Science | Scoop.it

Researchers at Harvard-affiliated Boston Children’s Hospital have, for the first time, visualized the origins of cancer from the first affected cell and watched its spread in a live animal. Their work, published in the Jan. 29 issue of Science, could change the way scientists understand melanoma and other cancers and lead to new, early treatments before the cancer has taken hold.


“An important mystery has been why some cells in the body already have mutations seen in cancer, but do not yet fully behave like the cancer,” says the paper’s first author, Charles Kaufman, a postdoctoral fellow in the Zon Laboratory at Boston Children’s Hospital. “We found that the beginning of cancer occurs after activation of an oncogene or loss of a tumor suppressor, and involves a change that takes a single cell back to a stem cell state.”


That change, Kaufman and colleagues found, involves a set of genes that could be targeted to stop cancer from ever starting. The study imaged live zebrafish over time to track the development of melanoma. All the fish had the human cancer mutation BRAFV600E — found in most benign moles — and had also lost the tumor suppressor gene p53.


Kaufman and colleagues engineered the fish to light up in fluorescent green if a gene called crestin was turned on — a “beacon” indicating activation of a genetic program characteristic of stem cells. This program normally shuts off after embryonic development, but occasionally, in certain cells and for reasons not yet known, crestin and other genes in the program turn back on.


“Every so often we would see a green spot on a fish,” said Leonard Zon, director of the Stem Cell Research Program at Boston Children’s and senior investigator on the study. “When we followed them, they became tumors 100 percent of the time.”


When Kaufman, Zon, and colleagues looked to see what was different about these early cancer cells, they found that crestin and the other activated genes were the same ones turned on during zebrafish embryonic development — specifically, in the stem cells that give rise to the pigment cells known as melanocytes, within a structure called the neural crest.


“What’s amazing about this group of genes is that they also get turned on in human melanoma,” said Zon, who is also a member of the Harvard Stem Cell Instituteand a Howard Hughes Medical Institute investigator. “It’s a change in cell fate, back to neural crest status.”


Finding these cancer-originating cells was tedious. Wearing goggles and using a microscope with a fluorescent filter, Kaufman examined the fish as they swam around, shooting video with his iPhone. Scanning 50 fish could take two to three hours. In 30 fish, Kaufman spotted a small cluster of green-glowing cells about the size of the head of a Sharpie marker — and in all 30 cases, these spots grew into melanomas. In two cases, he was able to see on a single green-glowing cell and watch it divide and ultimately become a tumor mass.


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Visualizing Cross-Sectional Data in a Real-World Context

Visualizing Cross-Sectional Data in a Real-World Context | Amazing Science | Scoop.it
Combining the capabilities of an open-source drawing tool with Google Earth maps allows researchers to visualize real-world cross-sectional data in three dimensions.


If you could fly around your research results in three dimensions, wouldn’t you like to do it? Visualizing research results properly during scientific presentations already does half the job of informing the public on the geographic framework of your research. Many scientists use Google Earth™ mapping service (V7.1.2.2041) because it’s a great interactive mapping tool for assigning geographic coordinates to individual data points, localizing a research area, and draping maps of results over Earth’s surface for displaying the results in three dimensions. Yet scientists often do not fully explore the Google Earth™ platform.


Visualizations of research results in vertical cross sections through these maps are often not shown at the same time as the maps. However, a few tutorials to display cross-sectional data in Google Earth™ do exist, and the workflow is rather simple. By importing cross-sectional data into in the open software SketchUp Make [Trimble Navigation Limited, 2016], any spatial model displaying research results can be exported to a vertical figure in Google Earth™. A website now explains an easy workflow including tips, and discusses some of the endless applications of the method. This workflow will give researchers better spatial visibility of their results and will allow for more dynamic scientific presentations.


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Astronomers Detect High-Energy Gamma Rays from Blazar 7.6 Billion Light-Years Away

Astronomers Detect High-Energy Gamma Rays from Blazar 7.6 Billion Light-Years Away | Amazing Science | Scoop.it
Using NASA’s Fermi Space Telescope, the Very Energetic Radiation Imaging Telescope Array System (VERITAS) in Arizona, and other telescopes, astronomers have detected high-energy gamma-ray emission from an extremely distant galaxy.


The gamma rays came from PKS 1441+25, a type of galaxy called a blazar, according to two studies published in the Astrophysical Journal LettersThis galaxy lies in the constellation Boötes, approximately 7.6 billion light-years away, and has a black hole of about 70 million solar masses at its center. If placed at the center of our own Solar System, the black hole’s event horizon would extend almost to the orbit of Mars.


High-energy gamma-rays from PKS 1441+25 were detected in April 2015 and observed by a range of telescopes sensitive to different wavelengths. NASA’s Fermi telescope detected gamma rays up to 33 billion electron volts (GeV). For comparison, visible light has energies between about 2 and 3 eV.


“Detecting these very energetic gamma rays with Fermi, as well as seeing flaring at optical and X-ray energies with NASA’s Swift satellite, made it clear that PKS 1441+25 had become a good target for MAGIC,” said Dr Luigi Pacciani of the Italian National Institute for Astrophysics in Rome, who is a member of the Major Atmospheric Gamma-ray Imaging Cerenkov (MAGIC) experiment.


The MAGIC team detected gamma rays with energies ranging from 40 to 250 GeV. “Because PKS 1441+25 is so far away, we didn’t have a strong expectation of detecting gamma rays with energies this high,” said Dr Josefa Becerra Gonzalez of NASA’s Goddard Space Flight Center, a co-author of the MAGIC study.

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New hack-proof RFID chips could secure credit cards, key cards, and goods in warehouses

New hack-proof RFID chips could secure credit cards, key cards, and goods in warehouses | Amazing Science | Scoop.it

Researchers at MIT and Texas Instruments have developed a new type of radio frequency identification (RFID) chip that is virtually impossible to hack. If such chips were widely adopted, it could mean that an identity thief couldn’t steal your credit card number or key card information by sitting next to you at a café, and high-tech burglars couldn’t swipe expensive goods from a warehouse and replace them with dummy tags.


Texas Instruments has built several prototypes of the new chip, to the researchers’ specifications, and in experiments the chips have behaved as expected. The researchers presented their research this week at the International Solid-State Circuits Conference, in San Francisco.


According to Chiraag Juvekar, a graduate student in electrical engineering at MIT and first author on the new paper, the chip is designed to prevent so-called side-channel attacks. Side-channel attacks analyze patterns of memory access or fluctuations in power usage when a device is performing a cryptographic operation, in order to extract its cryptographic key.


“The idea in a side-channel attack is that a given execution of the cryptographic algorithm only leaks a slight amount of information,” Juvekar says. “So you need to execute the cryptographic algorithm with the same secret many, many times to get enough leakage to extract a complete secret.”


One way to thwart side-channel attacks is to regularly change secret keys. In that case, the RFID chip would run a random-number generator that would spit out a new secret key after each transaction. A central server would run the same generator, and every time an RFID scanner queried the tag, it would relay the results to the server, to see if the current key was valid.


The researchers’ new chip uses a bank of 3.3-volt capacitors as an on-chip energy source. But it also features 571 1.5-volt cells that are discretely integrated into the chip’s circuitry. When the chip’s power source — the external scanner — is removed, the chip taps the 3.3-volt capacitors and completes as many operations as it can, then stores the data it’s working on in the 1.5-volt cells.


When power returns, before doing anything else the chip recharges the 3.3-volt capacitors, so that if it’s interrupted again, it will have enough power to store data. Then it resumes its previous computation. If that computation was an update of the secret key, it will complete the update before responding to a query from the scanner. Power-glitch attacks won’t work.


Because the chip has to charge capacitors and complete computations every time it powers on, it’s somewhat slower than conventional RFID chips. But in tests, the researchers found that they could get readouts from their chips at a rate of 30 per second, which should be more than fast enough for most RFID applications.


“In the age of ubiquitous connectivity, security is one of the paramount challenges we face,” says Ahmad Bahai, chief technology officer at Texas Instruments. “Because of this, Texas Instruments sponsored the authentication tag research at MIT that is being presented at ISSCC. We believe this research is an important step toward the goal of a robust, low-cost, low-power authentication protocol for the industrial Internet.”

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WHO Extremely Alarmed by Zika, Cases Could Reach 4 Million

WHO Extremely Alarmed by Zika, Cases Could Reach 4 Million | Amazing Science | Scoop.it

From October 2015 to January 2016, there were almost 4,000 cases of babies born with microcephaly in Brazil. Before then, there were just 150 cases per year. The suspected culprit is a mosquito-borne virus called Zika. Officials in Colombia, Ecuador, El Salvador and Jamaica have suggested that women delay becoming pregnant. And the Centers for Disease Control and Prevention has advised pregnant women to postpone travel to countries where Zika is active. Zika virus was first detected in Zika Forest in Uganda in 1947 in a rhesus monkey, and again in 1948 in the mosquito Aedes africanus, which is the forest relative of Aedes aegyptiAedes aegypti and Aedes albopictus can both spread Zika. Sexual transmission between people has also been reported.


The World Health Organization says it is likely that the virus will spread, as the mosquitoes that carry the virus are found in almost every country in the Americas. Zika virus was discovered almost 70 years ago, but wasn’t associated with outbreaks until 2007.


The World Health Organization (WHO) expects the Zika virus, which is spreading through the Americas, to affect between three million and four million people, a disease expert said recently. The WHO's director-general said the spread of the mosquito-borne disease had gone from a mild threat to one of alarming proportions.


Marcos Espinal, an infectious disease expert at the WHO's Americas regional office, said: "We can expect 3 to 4 million cases of Zika virus disease". He gave no time frame. There is no vaccine or treatment for Zika, which is a close cousin of dengue and chikungunya and causes mild fever, rash and red eyes. An estimated 80 percent of people infected have no symptoms, making it difficult for pregnant women to know whether they have been infected.


WHO Director-General Margaret Chan said the organization's will convene an emergency committee on Monday to help determine the level of the international response to an outbreak of the virus spreading from Brazil that is believed to be linked to severe birth defects.


"The level of alarm is extremely high," Chan told WHO executive board members at a meeting in Geneva. "As of today, cases have been reported in 23 countries and territories in the (Americas) region."


Brazil's Health Ministry said in November 2015 that Zika was linked to a fetal deformation known as microcephaly, in which infants are born with abnormally small heads Brazil has reported 3,893 suspected cases of microcephaly, the WHO said last week, more than 30 times more than in any year since 2010 and equivalent to 1-2 percent of all newborns in the state of Pernambuco, one of the worst-hit areas.

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Leonardo Wild's curator insight, February 3, 8:24 AM

Of course WHO would. Not much when it comes to drugs that have negative side effects, though, not necessarily blatant death, but certainly can destroy lives. That, though, is a taboo subject ever since Pasteur came on the scene.

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Bringing time, space together for universal symmetry

Bringing time, space together for universal symmetry | Amazing Science | Scoop.it

New research from Griffith University’s Centre for Quantum Dynamics is broadening perspectives on time and space. In a paper published in the prestigious journal Proceedings of the Royal Society A, Associate Professor Joan Vaccaro challenges the long-held presumption that time evolution — the incessant unfolding of the universe over time – is an elemental part of Nature.


In the paper, entitled "Quantum asymmetry between time and space," she suggests there may be a deeper origin due to a difference between the two directions of time: to the future and to the past.

"If you want to know where the universe came from and where it's going, you need to know about time," says Associate Professor Vaccaro.


"Experiments on subatomic particles over the past 50 years ago show that Nature doesn't treat both directions of time equally. "In particular, subatomic particles called K and B mesons behave slightly differently depending on the direction of time.


"When this subtle behavior is included in a model of the universe, what we see is the universe changing from being fixed at one moment in time to continuously evolving. In other words, the subtle behavior appears to be responsible for making the universe move forwards in time."


"Understanding how time evolution comes about in this way opens up a whole new view on the fundamental nature of time itself. It may even help us to better understand bizarre ideas such as travelling back in time."


According to the paper, an asymmetry exists between time and space in the sense that physical systems inevitably evolve over time whereas there is no corresponding ubiquitous translation over space. This asymmetry, long presumed to be elemental, is represented by equations of motion and conservation laws that operate differently over time and space.


However, Associate Professor Vaccaro used a "sum-over-paths formalism" to demonstrate the possibility of a time and space symmetry, meaning the conventional view of time evolution would need to be revisited.

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WIRED: Machine Learning Works Great — Mathematicians Just Don’t Know Why

WIRED: Machine Learning Works Great — Mathematicians Just Don’t Know Why | Amazing Science | Scoop.it
In mathematical terms, these supervised-learning systems are given a large set of inputs and the corresponding outputs; the goal is for a computer to learn the function that will reliably transform a new input into the correct output. To do this, the computer breaks down the mystery function into a number of layers of unknown functions called sigmoid functions. These S-shaped functions look like a street-to-curb transition: a smoothened step from one level to another, where the starting level, the height of the step and the width of the transition region are not determined ahead of time.

Inputs enter the first layer of sigmoid functions, which spits out results that can be combined before being fed into a second layer of sigmoid functions, and so on. This web of resulting functions constitutes the “network” in a neural network. A “deep” one has many layers.


Decades ago, researchers proved that these networks are universal, meaning that they can generate all possible functions. Other researchers later proved a number of theoretical results about the unique correspondence between a network and the function it generates. But these results assume networks that can have extremely large numbers of layers and of function nodes within each layer. In practice, neural networks use anywhere between two and two dozen layers. Because of this limitation, none of the classical results come close to explaining why neural networks and deep learning work as spectacularly well as they do.


It is the guiding principle of many applied mathematicians that if something mathematical works really well, there must be a good underlying mathematical reason for it, and we ought to be able to understand it. In this particular case, it may be that we don’t even have the appropriate mathematical framework to figure it out yet. Or, if we do, it may have been developed within an area of “pure” mathematics from which it hasn’t yet spread to other mathematical disciplines.


Another technique used in machine learning is unsupervised learning, which is used to discover hidden connections in large data sets. Let’s say, for example, that you’re a researcher who wants to learn more about human personality types. You’re awarded an extremely generous grant that allows you to give 200,000 people a 500-question personality test, with answers that vary on a scale from one to 10. Eventually you find yourself with 200,000 data points in 500 virtual “dimensions”—one dimension for each of the original questions on the personality quiz. These points, taken together, form a lower-dimensional “surface” in the 500-dimensional space in the same way that a simple plot of elevation across a mountain range creates a two-dimensional surface in three-dimensional space.


What you would like to do, as a researcher, is identify this lower-dimensional surface, thereby reducing the personality portraits of the 200,000 subjects to their essential properties—a task that is similar to finding that two variables suffice to identify any point in the mountain-range surface. Perhaps the personality-test surface can also be described with a simple function, a connection between a number of variables that is significantly smaller than 500. This function is likely to reflect a hidden structure in the data.


In the last 15 years or so, researchers have created a number of tools to probe the geometry of these hidden structures. For example, you might build a model of the surface by first zooming in at many different points. At each point, you would place a drop of virtual ink on the surface and watch how it spread out. Depending on how the surface is curved at each point, the ink would diffuse in some directions but not in others. If you were to connect all the drops of ink, you would get a pretty good picture of what the surface looks like as a whole. And with this information in hand, you would no longer have just a collection of data points. Now you would start to see the connections on the surface, the interesting loops, folds and kinks. This would give you a map for how to explore it.


These methods are already leading to interesting and useful results, but many more techniques will be needed. Applied mathematicians have plenty of work to do. And in the face of such challenges, they trust that many of their “purer” colleagues will keep an open mind, follow what is going on, and help discover connections with other existing mathematical frameworks. Or perhaps even build new ones.

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Revolutionizing heat transport: Quantum-limited heat conduction over macroscopic distances

Revolutionizing heat transport: Quantum-limited heat conduction over macroscopic distances | Amazing Science | Scoop.it

Scientists at Aalto University, Finland, have made a breakthrough in physics. They succeeded in transporting heat maximally effectively ten thousand times further than ever before. The discovery may lead to a giant leap in the development of quantum computers.


Heat conduction is a fundamental physical phenomenon utilized, for example, in clothing, housing, car industry, and electronics. Thus our day-to-day life is inevitably affected by major shocks in this field. The research group, led by quantum physicist Mikko Möttönen has now made one of these groundbreaking discoveries. This new invention revolutionizes quantum-limited heat conduction which means as efficient heat transport as possible from point A to point B. This is great news especially for the developers of quantum computers.


Quantum technology is still a developing research field, but its most promising application is the super-efficient quantum computer. In the future, it can solve problems that a normal computer can never crack. The efficient operation of a quantum computer requires that it can be cooled down efficiently. At the same time, a quantum computer is prone to errors due to external noise.


Möttönen's innovation may be utilized in cooling quantum processors very efficiently and so cleverly that the operation of the computer is not disturbed.


"Our research started already in 2011 and advanced little by little. It feels really great to achieve a fundamental scientific discovery that has real practical applications", Professor Mikko Möttönen rejoices.


In the QCD Labs in Finland, Möttönen's research group succeeded in measuring quantum-limited heat transport over distances up to a meter. A meter doesn't sound very long at first, but previously scientists have been able to measure such heat transport only up to distances comparable to the thickness of a human hair.


"For computer processors, a meter is an extremely long distance. Nobody wants to build a larger processor than that", stresses Möttönen.

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Can We Decipher the Language of the Brain?

Can We Decipher the Language of the Brain? | Amazing Science | Scoop.it

Understanding how brains work is one of the greatest scientific challenges of our times, but despite the impression sometimes given in the popular press, researchers are still a long way from some basic levels of understanding. A project recently funded by the Obama administration's BRAIN (Brain Research through Advancing Innovative Neurotechnologies) initiative is one of several approaches promising to deliver novel insights by developing new tools that involves a marriage of nanotechnology and optics.


There are close to 100 billion neurons in the human brain. Researchers know a lot about how these individual cells behave, primarily through “electrophysiology,” which involves sticking fine electrodes into cells to record their electrical activity. We also know a fair amount about the gross organization of the brain into partially specialized anatomical regions, thanks to whole-brain imaging technologies like functional magnetic resonance imaging (fMRI), which measure how blood oxygen levels change as regions that work harder demand more oxygen to fuel metabolism. We know little, however, about how the brain is organized into distributed “circuits” that underlie faculties like, memory or perception. And we know even less about how, or even if, cells are arranged into “local processors” that might act as components in such networks.


We also lack knowledge regarding the “code” large numbers of cells use to communicate and interact. This is crucial, because mental phenomena likely emerge from the simultaneous activity of many thousands, or millions, of interacting neurons. In other words, neuroscientists have yet to decipher the “language” of the brain. “The first phase is learning what the brain's natural language is. If your resolution [in a hypothetical language detector] is too coarse, so you're averaging over paragraphs, or chapters, you can't hear individual words or discern letters,” says physicist Michael Roukes of the California Institute of Technology, one of the authors of the “Brain Activity Map” (BAM) paper published in 2012 inNeuron that inspired the BRAIN Initiative. “Once we have that, we could talk to the brain in complete sentences.”


This is the gap BRAIN aims to address. Launched in 2014 with an initial pot of more than $100 million, the idea is to encourage the development of new technologies for interacting with massively greater numbers of neurons than has previously been possible. The hope is that once researchers understand how the brain works (with cellular detail but across the whole brain) they'll have better understanding of neurodegenerative diseases, like Alzheimer's and psychiatric disorders like schizophrenia or depression.


Today’s state-of-the-art technology in the field is optical imaging, mainly using calcium indicators—fluorescent proteins introduced into cells via genetic tweaks, which emit light in response to the calcium level changes caused by neurons firing. These signals are recorded using special microscopes that produce light, as the indicators need to absorb photons in order to then emit these light particles. This can be combined with optogenetics, a technique that genetically modifies cells so they can be activated using light, allowing researchers to both observe and control neural activity.


Some incredible advances have already been made using these tools. For example, researchers at the Howard Hughes Medical Institute’s Janelia Farm Research Campus, led by Misha Ahrens, published a study in 2013 in Nature Methods in which they recorded activity from almost all of the neurons of zebra fish larvae brains. Zebra fish larvae are used because they are easily genetically tweaked, small and, crucially, transparent. The researchers refined a technique called light-sheet microscopy, which uses lasers to produce planes of light that illuminate the brain one cross-section at a time. The fish were genetically engineered with calcium indicators so the researchers were able to generate two-dimensional pictures of neural activity, which they then stacked into three-dimensional images, capturing 90 percent of the activity of the zebra fish’s 100,000 brain cells.


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MIT wins design competition for Elon Musk's Hyperloop

MIT wins design competition for Elon Musk's Hyperloop | Amazing Science | Scoop.it
MIT student engineers won a competition to transform SpaceX and Tesla Motors co-founder Elon Musk's idea into a design for a Hyperloop to move pods of people at high speed.


An image released by Tesla Motors, is a sketch of the Hyperloop capsule with passengers onboard. . Billionaire entrepreneur Elon Musk on Monday, Aug. 12, 2013 unveiled a concept for a transport system he says would make the nearly 400-mile trip in half the time it takes an airplane. The "Hyperloop" system would use a large tube with capsules inside that would float on air, traveling at over 700 miles per hour.


The Massachusetts Institute of Technology, based in Cambridge, Massachusetts, was named the winner Saturday after a competition among more than 1,000 college students at Texas A&M University in College Station. The Hyperloop is a high-speed ground transport concept proposed by Musk to transport "pods" of 20 to 30 people through a 12-foot diameter tube at speeds of roughly 700 mph. More than 100 university teams presented design concepts to a panel of judges in an event that began Friday.


Delft University of Technology from The Netherlands finished second, the University of Wisconsin third, Virginia Tech fourth and the University of California, Irvine, fifth.


The top teams will build their pods and test them at the world's first Hyperloop Test Track, being built adjacent to SpaceX's Hawthorne, California, headquarters.


Inventor Musk to share plans for high-speed travel (Update)


More information: hyperloop.tamu.edu/ 

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A pulsating star in the constellation Lyra revealed a peculiar mathematical object

A pulsating star in the constellation Lyra revealed a peculiar mathematical object | Amazing Science | Scoop.it

A pulsating star in the constellation Lyra generates a unique fractal pattern that hints at unknown stellar processes.


What struck John Learned about the blinking of KIC 5520878, a bluish-white star 16,000 light-years away, was how artificial it seemed. A “variable” star, KIC 5520878 brightens and dims in a six-hour cycle, seesawing between cool-and-clear and hot-and-opaque. Overlaying this rhythm is a second, subtler variation of unknown origin; this frequency interplays with the first to make some of the star’s pulses brighter than others. In the fluctuations, Learned had identified interesting and, he thought, possibly intelligent sequences, such as prime numbers (which have been floated as a conceivable basis of extraterrestrial communication). He then found hints that the star’s pulses were chaotic.


But when Learned mentioned his investigations to a colleague, William Ditto, last summer, Ditto was struck by the ratio of the two frequencies driving the star’s pulsations. “I said, ‘Wait a minute, that’s the golden mean.’” This irrational number, which begins 1.618, is found in certain spirals, golden rectangles and now the relative speeds of two mysterious stellar processes. It meant that the blinking of KIC 5520878 wasn’t an extraterrestrial signal, Ditto realized, but something else that had never before been found in nature: a mathematical curiosity caught halfway between order and chaos called a “strange nonchaotic attractor.”


Dynamical systems — such as pendulums, the weather and variable stars — tend to fall into circumscribed patterns of behavior that are a subset of all the ways they could possibly behave. A pendulum wants to swing from side to side, for example, and the weather stays within a general realm of possibility (it will never be zero degrees in summer). Plotting these patterns creates a shape called an “attractor.”


Mathematicians in the 1970s used attractors to model the behavior of chaotic systems like the weather, and they found that the future path of such a system through its attractor is extremely dependent on its exact starting point. This sensitivity to initial conditions, known as the butterfly effect, makes the behavior of chaotic systems unpredictable; you can’t tell the forecast very far in advance if the flap of a butterfly’s wings today can make the difference, two weeks from now, between sunshine and a hurricane. The infinitely detailed paths that most chaotic systems take through their attractors are called “fractals.” Zoom in on a fractal, and new variations keep appearing, just as new outcrops appear whenever you zoom in on the craggy coastline of Great Britain. Attractors with this fractal structure are called “strange attractors.”


Then in 1984, mathematicians led by Celso GrebogiEdward Ott and James Yorke of the University of Maryland in College Park discovered an unexpected new category of objects — strange attractors shaped not by chaos but by irrationality. These shapes formed from the paths of a system driven at two frequencies with no common multiple — that is, frequencies whose ratio was an irrational number, like pi or the golden mean. Unlike other strange attractors, these special “nonchaotic” ones did not exhibit a butterfly effect; a small change to a system’s initial state had a proportionally small effect on its resulting fractal journey through its attractor, making its evolution relatively stable and predictable.


“It was quite surprising to find these fractal structures in something that was totally nonchaotic,” said Grebogi, a Brazilian chaos theorist who is now a professor at the University of Aberdeen in Scotland.


Though no example could be positively identified, scientists speculated that strange nonchaotic attractors might be everywhere around and within us. It seemed possible that the climate, with its variable yet stable patterns, could be such a system. The human brain might be another.


The first laboratory demonstration of strange nonchaotic dynamics occurred in 1990, spearheaded by Ott and none other than William Ditto. Working at the Naval Surface Warfare Center in Silver Spring, Maryland, Ditto, Ott and several collaborators induced a magnetic field inside a metallic strip of tinsel called a “magnetoelastic ribbon” and varied the field’s strength at two different frequencies related by the golden ratio. The ribbon stiffened and relaxed in a strange nonchaotic pattern, bringing to life the mathematical discovery from six years earlier. “We were the first people to see this thing; we were pleased with that,” Ditto said. “Then I forgot about it for 20 years.


The study of variable stars entered boom times in 2009 with the launch of the Kepler telescope, which looked for small aberrations in starlight as a sign of distant planets. The telescope gathered a trove of unprecedented data on the pulsations of variable stars throughout the galaxy. Other, ground-based surveys have added further riches.


The data revealed subtle variations in many of the stars’ pulsations that hinted at stellar processes beyond those described by Eddington. The pulses of starlight could be separated into two main frequencies: a faster one like the beat of a snare drum and a slower one like a gong, with the two rhythms played out of sync. And in more than 100 of these variable stars — including those, like KIC 5520878, belonging to a subclass called “RRc” — the ratios defining the duration of one frequency relative to the other inexplicably fell between 1.58 and 1.64.

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Galaxy Clusters Reveal New Dark Matter Insights

Galaxy Clusters Reveal New Dark Matter Insights | Amazing Science | Scoop.it
Dark matter is a mysterious cosmic phenomenon that accounts for 27 percent of all matter and energy. Though dark matter is all around us, we cannot see it or feel it. But scientists can infer the presence of dark matter by looking at how normal matter behaves around it.

Galaxy clusters, which consist of thousands of galaxies, are important for exploring dark matter because they reside in a region where such matter is much denser than average. Scientists believe that the heavier a cluster is, the more dark matter it has in its environment. But new research suggests the connection is more complicated than that.

"Galaxy clusters are like the large cities of our universe. In the same way that you can look at the lights of a city at night from a plane and infer its size, these clusters give us a sense of the distribution of the dark matter that we can't see," said Hironao Miyatake at NASA's Jet Propulsion Laboratory, Pasadena, California.

A new study in Physical Review Letters, led by Miyatake, suggests that the internal structure of a galaxy cluster is linked to the dark matter environment surrounding it. This is the first time that a property besides the mass of a cluster has been shown to be associated with surrounding dark matter.

Researchers studied approximately 9,000 galaxy clusters from the Sloan Digital Sky Survey DR8 galaxy catalog, and divided them into two groups by their internal structures: one in which the individual galaxies within clusters were more spread out, and one in which they were closely packed together. The scientists used a technique called gravitational lensing -- looking at how the gravity of clusters bends light from other objects -- to confirm that both groups had similar masses.

But when the researchers compared the two groups, they found an important difference in the distribution of galaxy clusters. Normally, galaxy clusters are separated from other clusters by 100 million light-years on average. But for the group of clusters with closely packed galaxies, there were fewer neighboring clusters at this distance than for the sparser clusters. In other words, the surrounding dark-matter environment determines how packed a cluster is with galaxies.

"This difference is a result of the different dark-matter environments in which the groups of clusters formed. Our results indicate that the connection between a galaxy cluster and surrounding dark matter is not characterized solely by cluster mass, but also its formation history," Miyatake said.

Study co-author David Spergel, professor of astronomy at Princeton University in New Jersey, added, "Previous observational studies had shown that the cluster's mass is the most important factor in determining its global properties. Our work has shown that 'age matters': Younger clusters live in different large-scale dark-matter environments than older clusters."

The results are in line with predictions from the leading theory about the origins of our universe. After an event called cosmic inflation, a period of less than a trillionth of a second after the big bang, there were small changes in the energy of space called quantum fluctuations. These changes then triggered a non-uniform distribution of matter. Scientists say the galaxy clusters we see today have resulted from fluctuations in the density of matter in the early universe.

"The connection between the internal structure of galaxy clusters and the distribution of surrounding dark matter is a consequence of the nature of the initial density fluctuations established before the universe was even one second old," Miyatake said.

Researchers will continue to explore these connections.

"Galaxy clusters are remarkable windows into the mysteries of the universe. By studying them, we can learn more about the evolution of large-scale structure of the universe, and its early history, as well as dark matter and dark energy," Miyatake said.
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