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Leaf Shape Evolution Through Duplication, Regulatory Domain Diversification and Loss of a Homeobox Gene

Leaf Shape Evolution Through Duplication, Regulatory Domain Diversification and Loss of a Homeobox Gene | Amazing Science | Scoop.it

Spinach looks nothing like parsley, and basil bears no resemblance to thyme. Each plant has a typical leaf shape that can differ even within the same family. The information about what shape leaves will be is stored in the DNA. According to researchers at the Max Planck Institute for Plant Breeding Research in Cologne, the hairy bittercress (Cardamine hirsuta) has a particular gene to thank for its dissected leaves. This homeobox gene inhibits cell proliferation and growth between leaflets, allowing them to separate from each other. The thale cress Arabidopsis thaliana does not have this gene. Therefore, its leaves are not dissected, but simple and entire.


Miltos Tsiantis and his colleagues at the Max Planck Institute for Plant Breeding Research in Cologne discovered the new gene when comparing two plants from the Brassicaceae family: Cardamine hirsuta has dissected leaves that form leaflets and Arabidopsis thaliana has simple leaves. The researchers identified the RCO (REDUCED COMPLEXITY) gene, which makes leaves of the hairy bittercress more complex. Arabidopsis lacks this gene and, accordingly, lacks leaflets. RCO is only active in growing leaves. RCO ensures that cell proliferation and growth is prevented in areas of the leaf margin between sites of leaflet formation. “The leaves of Arabidopsis are simple and entire because growth is not inhibited by the RCO gene,” explains Tsiantis. “If we had not compared the two plants we would never have discovered this difference, as it is impossible to find a gene where none exists,” he adds.


The scientists first identified the RCO gene through a mutation in the hairy bittercress. In the absence of functional RCO the hairy bittercress can no longer produces leaflets. The RCO gene belongs to a cluster of three genes, which arose during evolution through the duplication of a single gene. In the thale cress, the original triple cluster now consists of a single gene. When the scientists return the RCO gene to the thale cress in the laboratory, evolution is partially reversed. “The simple oval leaves of Arabidopsis now develop deep lobes” says Tsiantis, “The fact that the leaf shape becomes complex again through the transfer of the RCO gene alone, shows that most of the apparatus for the formation of leaflets must still be present in the thale cress and was not lost with the RCO gene.”


The research team also examined theRCO sequence in greater detail and found it is a  Homeobox gene. These genes function like genetic switches in that they activate or deactivate other genes. The scientists also demonstrated that RCO function is restricted to leaf shape; it does not decide whether leaves actually form. The loss of theRCO gene does not give rise to any other visible changes in the hairy bittercress. Therefore, its effect is limited to the inhibition of growth on the leaf margin. RCO does not work with the plant hormone auxin here. This specificity makes RCO a more likely driver of leaf shape evolution than any other genes identified to date. Tsiantis and his colleagues aim to decode its exact functionality in the months to come.

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Superbright fast X-rays image single layer of proteins, providing details of almost 25 percent of known proteins

Superbright fast X-rays image single layer of proteins, providing details of almost 25 percent of known proteins | Amazing Science | Scoop.it

In biology, a protein's shape is key to understanding how it causes disease or toxicity. Researchers who use X-rays to take snapshots of proteins need a billion copies of the same protein stacked and packed into a neat crystal. Now, scientists using exceptionally bright and fast X-rays can take a picture that rivals conventional methods with a sheet of proteins just one protein molecule thick.


Using a type of laser known as XFEL, the technique opens the door to learning the structural details of almost 25 percent of known proteins, many of which have been overlooked due to their inability to stack properly. The team of researchers led by the Department of Energy's Pacific Northwest and Lawrence Livermore National Laboratories report their results with this unique form of X-ray diffraction in the March issue of the International Union of Crystallography Journal.


"In this paper, we're proving it's possible to use an XFEL to study individual monolayers of protein," said PNNL microscopist James Evans. "Just being able to see any diffraction is brand new."


Evans co-led the team of two dozen scientists with LLNL physicist Matthias Frank. The bright, fast X-rays were produced at the Linac Coherent Light Source at SLAC National Accelerator Laboratory in Menlo Park, Calif., the newest of DOE's major X-ray light source facilities at the national laboratories. LCLS, currently the world's most powerful X-ray laser, is an X-ray free-electron laser. It produces beams millions of times brighter than earlier X-ray light sources.


Coming in at around 8 angstrom resolution (which can make out items a thousand times smaller than the width of a hair), the proteins appear slightly blurry but match the expected view based on previous research. Evans said this level of clarity would allow researchers, in some cases, to see how proteins change their shape as they interact with other proteins or molecules in their environment.


To get a clearer view of protein monolayers using XFEL, the team will need to improve the resolution to 1 to 3 angstroms, as well as take images of the proteins at different angles, efforts that are currently underway.


Researchers have been using X-ray crystallography for more than 60 years to determine the shape and form of proteins that form the widgets and gears of a living organism's cells. The conventional method requires, however, that proteins stack into a large crystal, similar to how oranges stack in a crate. The structure of more than 80,000 proteins have been determined this way, leading to breakthroughs in understanding of diseases, pathogens, and how organisms grow and develop.


But many proteins found in nature do not stack easily. Some jut from the fatty membranes that cover cells, detecting and interacting with other cells and objects, such as viruses or bacteria, in the surrounding area. These proteins are not used to having others of their kind stack on top. These so-called membrane proteins make up about 25 percent of all proteins but only 2 percent of proteins that researchers have determined structures for.


Evans, Frank and their team wanted to push this further. The team worked on a way to create one-sheet-thick crystals of two different proteins — a protein called streptavidin and a membrane protein called bacteriodopsin. The structures of both proteins are well-known to scientists, which gave the team something to compare their results to.


The team shined the super-bright X-rays for a brief moment — about 30 femtoseconds, a few million billionths of a second — on the protein crystals. They created so much data in the process that it took them more than a year to analyze all of it.


The resulting images look like the known structures, validating this method. Next, the researchers will try to capture proteins changing shape as they engage in a chemical reaction. For this, even shorter flashes of X-rays might be needed to see the action clearly.

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Optogenetics Makes Mice Resistant to Pain

Optogenetics Makes Mice Resistant to Pain | Amazing Science | Scoop.it

Scientists turn pain on and off, with a beam of light.


Some of the mice squeaked in agony when researchers aimed a blue light at their paws. Other mice felt nothing at all when zapped with a laser.

In the latest demonstration of optogenetics, a versatile but complex technology for controlling nerve cells, a research team at Stanford University has sketched out how patients afflicted by chronic pain might one day find relief: simply by pressing a bright flashlight to their skin.

“Patients could be given their own ability to create a pain block on demand,” says Michael Kaplitt, a neurosurgeon and chief scientific officer of Circuit Therapeutics, a three-year-old Palo Alto, California, biotechnology startup now working on a pain treatment along with the Stanford scientists.


Optogenetics is a breakthrough technology that is giving scientists precise control over what animals feel, how they behave, and even what they think. It relies on modifying the DNA of neurons so that they send signals—or are blocked from firing—in response to light (see “Brain Control”). The technique was invented nine years ago in the laboratory of Karl Deisseroth, one of Circuit’s cofounders and an author of the new pain study.


So far, the most striking use of optogenetics has been to produce effects directly inside animals’ brains, using light piped in with an implanted fiber-optic cable. In an earlier study, Deisseroth’s group made mice feel fear or become fearless (“An On-Off Switch for Anxiety”).


Circuit, which now has 47 employees, is working to engineer light sources and perfect genetic tools to take advantage of optogenetics. Kaplitt says that in addition to its research on pain, the company hopes to figure out how to treat serious psychiatric disease with implants that carry light into the brain.


But controlling nerves outside the brain could prove easier. The sensitive nerve endings, or nociceptors, that fire off warnings in response to heat or pressure lie only two hair-breadths beneath human skin, and could be controlled by a bright handheld light. “We have engineers thinking about what that kind of device would look like,” says Kaplitt. “Pain is a perception. So the idea is to stop the perception of it.”


In the Stanford group’s latest work, published in the journal Nature Biotechnology, they first used gene therapy to install light-sensitive molecules into the nerve endings in the skin of mice. Each animal was then placed into a small plexiglass chamber with a transparent floor.


When the researchers shined blue light through the floor, the mice “flinched,” cried out, or “engaged in prolonged paw licking,” all signs of pain. The team could also block sensation. In those tests, mice that were bathed in yellow light designed to block nerve impulses weren’t greatly bothered by a band pinching their leg. When the researchers pointed hot lasers at their paws, they were slow to react.

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Simply become immortal: AI will talk to loved ones when you die and preserve your digital footprint

Simply become immortal: AI will talk to loved ones when you die and preserve your digital footprint | Amazing Science | Scoop.it

Eterni.me wants to build an AI from your digital footprint, so you can have virtual chats with loved ones from beyond the grave.


"We don't try to replace humans or give false hopes to people grieving." Romanian design consultant Marius Ursache, cofounder of Eterni.me, needs to clear this up quickly. Because when you're building a fledgling artificial intelligence company that promises to bring back the dead -- or at least, their memories and character, as preserved in their digital footprint -- for virtual chats with loved ones, expect a lot of flack.


The site launched with the look of any other Silicon Valley internet startup, but a definitively new take on an old message. While social media companies want you to share and create the story of you while you're alive, and lifelogging company Memoto promises to capture "meaningful [and shareable] moments", Eterni.me wants to wrap that all up for those you leave behind into a cohesive AI they can chat with.


Three thousand people registered to the service within the first four days of the site going live, despite there being zero product to make use of (a beta version is slated for 2015). So with a year to ponder your own mortality, why the excitement for a technology that is, at this moment, merely a proof of concept? 


The company's motto is "it's like a Skype chat from the past," but it's still very much about crafting how the world sees you -- or remembers you, in this case -- just as you might pause and ponder on hitting Facebook's post button, wondering till the last if your spaghetti dinner photo/comment really gets the right message across. On its more troubling side, the site plays on the fear that you can no longer control your identity after you're gone; that you are in fact a mere mortal. "The moments and emotions in our lifetime define how we are seen by our family and friends. All these slowly fade away after we die -- until one day… we are all forgotten," it says in its opening lines -- scroll down and it provides the answer to all your problems: "Simply Become Immortal". Part of the reason we might identify as being immortal -- at least unconsciously, as Freud describes it -- is because we craft a life we believe will be memorable, or have children we believe our legacy will live on in. Eterni.me's comment shatters that illusion and could be seen as opportunistic on the founders' part. The site also goes on to promise a "virtual YOU" that can "offer information and advice to your family and friends after you pass away", a comfort to anyone worried about leaving behind a spouse or children.


The ultimate stumbling block might be, however, the something that's worse than the fear of being forgotten. Admitting you're going to die one day. It's a tough sell, to persuade someone to confess to the secret of their heroism.

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Laura E. Mirian, PhD's curator insight, February 17, 2014 10:47 AM

you can have virtual chats with loved ones from beyond the grave.

Laura E. Mirian, PhD's curator insight, February 23, 2014 10:34 AM

DON'T KNOW IF I WANT TO LIVE FOREVER IN THIS UNIVERSE-WHAT ABOUT YOU?

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Neutrino Experiments Come Closer to Seeing Charge-parity Violation

Neutrino Experiments Come Closer to Seeing Charge-parity Violation | Amazing Science | Scoop.it

Charge-parity (CP) violation—evidence that the laws of physics are different for particles and antiparticles—is often invoked as a “must” to explain why we observe more matter than antimatter in the universe. But the CP violation observed in interactions involving quarks is insufficient to explain this asymmetry. As a result, many theorists are looking toward leptons—and, specifically, neutrinos—for additional sources of CP violation. Researchers running the Tokai to Kamioka (T2K) experiment—a particle physics experiment at the Japan Proton Accelerator Research Complex (J-PARC)—have now made an important contribution toward the search for CP violation in neutrinos. Writing in Physical Review Letters, the T2K collaboration reports the strongest evidence to date for the appearance of electron neutrinos from a pure muon neutrino beam [1]. Their measurement allows them to determine a fundamental parameter of the standard model of particle physics, called θ13, which can in turn be used to make an early estimate of CP violation in neutrinos. Although this estimate has a large uncertainty, it will serve as a guide to future, more definitive neutrino experiments that are directly sensitive to CP violation.

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MicroRNA-Target Binding Structures Mimic MicroRNA Duplex Structures in Humans

MicroRNA-Target Binding Structures Mimic MicroRNA Duplex Structures in Humans | Amazing Science | Scoop.it

MicroRNAs (miRNAs) have emerged as key gene regulators in diverse biological pathways. These small non-coding RNAs bind to target sequences in mRNAs, typically resulting in repressed gene expression. Traditionally, researchers match a microRNA guide strand to mRNA sequences using sequence comparisons to predict its potential target genes. However, many of the predictions can be false positives due to limitations in sequence comparison alone. In a recently published study, scientists consider the association of two related RNA structures that share a common guide strand: the microRNA duplex and the microRNA-target binding structure. They have analyzed thousands of such structure pairs and found many of them share high structural similarity. From this investigation, they conclude that when predicting microRNA target genes, considering just the microRNA guide strand matches to gene sequences may not be sufficient – The microRNA duplex structure formed by the guide strand and its companion passenger strand must also be considered. They have also developed software to translate RNA binding structure into encoded representations, and we have also created novel automatic comparison methods utilizing such encoded representations to determine RNA structure similarity. The presented software and methods can be utilized in the other RNA secondary structure comparisons as well.

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Making predictions about the multiverse

Making predictions about the multiverse | Amazing Science | Scoop.it

A recent conference organized by the Fundamental Questions Institute (FQXi) in Puerto Rico about making predictions in cosmology, especially in the eternally inflating multiverse. Many physicists and cosmologists are thinking with some “confidence” that we live in a multiverse, more specifically one of the many universes in which low-energy physical laws take different forms. For example, these universes have different elementary particles with different properties, possibly different spacetime dimensions, and so on. This idea of the multiverse is not simply a result of random imagination by theorists, but is based on several pieces of observational and theoretical evidence.


Observationally, we have learned more and more that we live in a highly special universe—it seems that the “physical laws” of our universe (summarized in the form of standard models of particle physics and cosmology) takes such a special form that if its structure were varied slightly, then there would be no interesting structure in the universe, let alone intelligent life. It is hard to understand this fact unless there are many universes with varying “physical laws,” and we simply happen to emerge in a universe which allows for intelligent life to develop (which seems to require special conditions). With multiple universes, we can understand the “specialness” of our universe precisely as we understand the “specialness” of our planet Earth (e.g. the ideal distance from the sun), which is only one of the many planets out there.


Perhaps more nontrivial is the fact that our current theory of fundamental physics leads to this picture of the multiverse in a very natural way. Imagine that at some point in the history of the universe, space is exponentially expanding. This expansion—called inflation—occurs when space is filled with a “positive vacuum energy”, which happens quite generally. We knew, already in 80′s, that such inflation is generically eternal. During inflation, various non-inflating regions called bubble universes—of which our own universe could be one—may form, much like bubbles in boiling water. Since ambient space expands exponentially, however, these bubbles do not percolate; rather, the process of creating bubble universes lasts forever in an eternally inflating background. Now, recent progress in string theory suggests that low energy theories describing phyics in these bubble universes (such as the elementary particle content and their properties) may differ bubble by bubble. This is precisely the setup needed to understand the “specialness” of our universe because of the selection effect associated with our own existence, as described above.


This particular version of the multiverse—called the eternally inflating multiverse—is very attractive. It is theoretically motivated and has a potential to explain various features seen in our universe. The eternal nature of inflation, however, causes a serious issue of predictivity. Because the process of creating bubble universes occurs infinitely many times, “In an eternally inflating universe, anything that can happen will happen; in fact, it will happen an infinite number of times,” as phrased in an article by Alan Guth.


The picture presented here does not solve all the problems in eternally inflating cosmology. What is the actual quantum state of the multiverse? What is its “initial conditions”? What is time? How does it emerge? The basic idea is that the state of the multiverse (which may be selected uniquely by the normalizability condition) never changes, and yet time appears as an emergent concept locally in branches as physical correlations among objects (along the lines of an old idea by DeWitt). 

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Redlight Special: Optogenetic Toolkit Goes Multicolor

Redlight Special: Optogenetic Toolkit Goes Multicolor | Amazing Science | Scoop.it
New light-sensitive proteins allow scientists to study how multiple sets of neurons interact with each other.


Optogenetics is a technique that allows scientists to control neurons’ electrical activity with light by engineering them to express light-sensitive proteins. Within the past decade, it has become a very powerful tool for discovering the functions of different types of cells in the brain.

Most of these light-sensitive proteins, known as opsins, respond to light in the blue-green range. Now, a team led by MIT has discovered an opsin that is sensitive to red light, which allows researchers to independently control the activity of two populations of neurons at once, enabling much more complex studies of brain function.


Opsins occur naturally in many algae and bacteria, which use the light-sensitive proteins to help them respond to their environment and generate energy.


To achieve optical control of neurons, scientists genetically modify brain cells of mice to express the gene for an opsin, which transports ions across the cell’s membrane to alter its voltage. Depending on the opsin used, shining light on the cell either lowers the voltage and silences neuron firing, or boosts voltage and provokes the cell to generate an electrical impulse. This effect is nearly instantaneous and easily reversible.


Using this approach, researchers can selectively turn a population of cells on or off and observe what happens in the brain. However, until now, they could activate only one population at a time, because the only opsins that responded to red light also responded to blue light, so they couldn’t be paired with other opsins to control two different cell populations.


To seek additional useful opsins, the MIT researchers worked with Gane Ka-Shu Wong, a professor of medicine and biological sciences at the University of Alberta, the paper’s other senior author. Wong’s team  is sequencing the transcriptomes of 1,000 plants, including some algae. (The transcriptome is similar to the genome but includes only the genes that are expressed by a cell, not the entirety of its genetic material.)


Once the team obtained genetic sequences that appeared to code for opsins, Klapoetke tested their light-responsiveness in mammalian brain tissue, working with Martha Constantine-Paton, an MIT professor of brain and cognitive sciences and of biology, a member of the McGovern Institute, and an author of the paper. The red-light-sensitive opsin, which the researchers named Chrimson, can mediate neural activity in response to light with a 735-nanometer wavelength.


The researchers also discovered a blue-light-driven opsin that has two highly desirable traits: It operates at high speed, and it is sensitive to very dim light. This opsin, called Chronos, can be stimulated with levels of blue light that are too weak to activate Chrimson.


Most optogenetic studies thus far have been done in mice, but Chrimson could be used for optogenetic studies of fruit flies, a commonly used experimental organism. Researchers have had trouble using blue-light-sensitive opsins in fruit flies because the light can get into the flies’ eyes and startle them, interfering with the behavior being studied.

Vivek Jayaraman, a research group leader at Janelia Farms and an author of the paper, was able to show that this startle response does not occur when red light is used to stimulate Chrimson in fruit flies.

Because red light is less damaging to tissue than blue light, Chrimson also holds potential for eventual therapeutic use in humans, Boyden says. Animal studies with other opsins have shown promise in helping to restore vision after the loss of photoreceptor cells in the retina.

The researchers are now trying to modify Chrimson to respond to light in the infrared range. They are also working on making both Chrimson and Chronos faster and more light sensitive.

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Why De-Extinction of Birds is a Challenge – The Passenger Pidgeon Case

Why De-Extinction of Birds is a Challenge – The Passenger Pidgeon Case | Amazing Science | Scoop.it

Birds are a huge challenge for de-extinction for two big reasons. The first is because less genomic research has been performed on birds than on mammals (but reptiles, amphibians, fish, invertebrates and plants are even less understood). We don’t know how precisely how the majority of gene pathways in birds work on the cellular levels and up.


Also, birds have no uterus. The reason that the absence of a uterus is a problem for cloning relates to how cloning is done. When you take the nucleus out of an egg cell you kill that cell, it is completely dead. Even after you put a new nucleus in it, the cell is still dead. You have to bring the cell back to life, just like when you shock someone’s heart into beating again. You run electricity through the newly cloned cell to get it to divide. The problem here is that you have to keep stimulating cell division for many generations, up to several hundred and even a few thousand cells before the embryo will develop on its own without assistance. Therefore you cannot take a single cloned cell and implant it into an ovary, oviduct, uterus or any reproductive organ and get it to grow – you have to grow it in the lab and then implant a partially developed embryo. This is okay in a uterus because the embryo implants and develops in a fixed place. In a bird, the embryo is in constant motion within the female’s body – literally tumbling down the oviduct as the oviduct coats the eggshell around the embryo. To implant a cloned embryo one would have to take out the developing embryo from within a developing hard shelled egg within the female’s body and replace it with the cloned embryo – and hope that the embryo integrates into the yolk of the egg and that all the puncturing doesn’t deform the egg or harm the female. So you can see it’s very very tricky.


Are there ways to introduce an extinct bird’s genetics into an embryo without cloning? You can introduce cells into the embryo, which will integrate and create a chimeric bird – a bird that has a patchwork of tissues made of cells of both the original embryo and the cells that were introduced. This can be done after the egg is laid, avoiding tampering with the mother’s internal organ systems. The problem for de-extinction is that adult stem cells (or induced Pluripotent Stem cells, iPCs) cannot contribute to the germ line, only Embryonic stem cells can contribute to the germ line. We can’t easily use embryonic stem cells to recreate the passenger pigeon genome. After as few as seven days in a lab culture, embryonic stem cells have undergone enough cell division to be adult stem cells, and lose the ability to become germ cells. A process to use embryonic stem cells would require introducing a mutation to a band-tailed pigeon embryonic stem cell in less than a matter of a few days, then put it into an embryo and hatch a chimera. This would then require hundreds to even thousands of generations of chimeric birds until we have a passenger pigeon. It would be far more efficient to introduce the thousands of mutations in cell lines, then create a bird. But by the time all the mutations were added, the cells would be adult stem cells. You could make as many chimeras as you want from these “de-extinct” stem cells, but they would never form a breeding line. This does not mean that stem cells cannot become germ cells under experimental conditions, what this means is that they do not naturally become germ cells when placed inside a developing bird embryo. It may be possible in the future to program iPSCs to become germ cells, but currently this is not possible.


Further reading: The Mammoth Cometh (NY Times)

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Quantum engineering pushes quantum absorption refrigerator beyond classical efficiency limits

Quantum engineering pushes quantum absorption refrigerator beyond classical efficiency limits | Amazing Science | Scoop.it

The laws of thermodynamics determine what is possible and impossible in classical systems. Lately, scientists have been working on establishing quantum analogues of these fundamental laws to determine the performance limits of quantum systems. Now in a new study, scientists have established the thermodynamic limits on quantum absorption refrigerators, and then somewhat counterintuitively show how quantum engineering techniques can push the refrigerators beyond these limits, resulting in superefficient cooling.


The findings show how quantum enhancements can allow quantum systems to exceed what is classically achievable, and marks a promising step toward the development of practical quantum cooling technologies. The researchers, Luis A. Correa, et al., from the University of La Laguna in Spain and the University of Nottingham in the UK, have published their paper on quantum-enhanced refrigeration in a recent issue of Nature Scientific Reports.


Whether classical or quantum in nature, refrigerators function by transporting energy from a cold reservoir (the object to be cooled) to a hot reservoir, usually with assistance from a power source or, in the case of an absorption refrigerator, an additional work reservoir.

"First patented by Einstein himself, absorption fridges are really 'cool,'" coauthor Gerardo Adesso at the University of Nottingham told Phys.org. "They refrigerate by absorbing heat from outside, without having to be plugged to a power socket. People use them, e.g., while camping, but these fridges have been traditionally hindered by quite a low cooling power." For any refrigerator, the efficiency of the refrigeration process cannot exceed the Carnot limit, or else it would violate the second law of thermodynamics.


In the new study, the scientists investigated the theoretical maximum efficiency of a quantum refrigerator operating at maximum power. Efficiency at maximum power is of greater practical interest than efficiency in general, since power vanishes at high efficiencies. Here, the scientists proved that the efficiency at maximum power of a quantum refrigerator of any kind is limited by a fraction of the Carnot limit.


"Discovering that all quantum absorption fridges admit a tight model-independent performance limit was indeed surprising," Adesso said. "Establishing these bounds on efficiency at maximum power for heat engines and refrigerators has been a long-standing problem in finite-time thermodynamics."


Although this limit holds for all models of quantum absorption refrigerators, it is not the final answer. In the second part of their paper, the researchers show that quantum refrigerators can boost their performance by exploiting the system's quantum features.

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A detailed map of Jupiter's moon Ganymede, which might be habitable one day

A detailed map of Jupiter's moon Ganymede, which might be habitable one day | Amazing Science | Scoop.it

One day, poor planet Earth will succumb to the centuries of abuse we've dealt her, shrivel up, and cease to support life. Then, if we're not already living in some Elysium-like habitat in space, we'll have to find a new home. Jupiter's moon, Ganymede, might just be it.


Ganymede with its underground ocean and rocky terrain is already being eyed by scientists as one of the solar system's few habitable environments. Until now, though, we haven't known exactly what was on that far away satellite which also happens to be the largest moon in our solar system. Thankfully, a team of Brown scientists and geologists fixed that problem by making this terrifically detailed map of Ganymede using images from NASA's Voyager and Galileo missions.


The map is a little intimidating at first, but once you delve into it, you'll realize that exploring the geography of Ganymede isn't so different from exploring the geography of Earth. Different colors represent the different elements that make up the moon's surface creating an almost marbled look as the minerals run together. Of course, Ganymede would need a little work before we can colonize it. But let's just hope we never have to.

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Microrobotic technique combines 3D printing and tissue engineering

Microrobotic technique combines 3D printing and tissue engineering | Amazing Science | Scoop.it

Researchers at Brigham and Women's Hospital (BWH) and Carnegie Mellon University have introduced a unique micro-robotic technique to assemble the components of complex materials, the foundation of tissue engineering and 3D printing, described in the Jan. 28, 2014, issue of Nature Communications ("Untethered micro-robotic coding of three-dimensional material composition").


Tissue engineering and 3D printing have become vitally important to the future of medicine for many reasons. The shortage of available organs for transplantation, for example, leaves many patients on lengthy waiting lists for life-saving treatment. Being able to engineer organs using a patient's own cells can not only alleviate this shortage, but also address issues related to rejection of donated organs. Developing therapies and testing drugs using current preclinical models have limitations in reliability and predictability. Tissue engineering provides a more practical means for researchers to study cell behavior, such as cancer cell resistance to therapy, and test new drugs or combinations of drugs to treat many diseases.


The presented approach uses untethered magnetic micro-robotic coding for precise construction of individual cell-encapsulating hydrogels (such as cell blocks). The micro-robot, which is remotely controlled by magnetic fields, can move one hydrogel at a time to build structures. This is critical in tissue engineering, as human tissue architecture is complex, with different types of cells at various levels and locations. When building these structures, the location of the cells is significant in that it will impact how the structure will ultimately function. "Compared with earlier techniques, this technology enables true control over bottom-up tissue engineering," explains Tasoglu.


Tasoglu and Demirci also demonstrated that micro-robotic construction of cell-encapsulating hydrogels can be performed without affecting cell vitality and proliferation. Further benefits may be realized by using numerous micro-robots together in bioprinting, the creation of a design that can be utilized by a bioprinter to generate tissue and other complex materials in the laboratory environment."


Our work will revolutionize three-dimensional precise assembly of complex and heterogeneous tissue engineering building blocks and serve to improve complexity and understanding of tissue engineering systems," said Metin Sitti, professor of Mechanical Engineering and the Robotics Institute and head of CMU's NanoRobotics Lab.


"We are really just beginning to explore the many possibilities in using this micro-robotic technique to manipulate individual cells or cell-encapsulating building blocks." says Demirci. "This is a very exciting and rapidly evolving field that holds a lot of promise in medicine."

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Deborah Verran's curator insight, February 14, 2014 10:07 PM

Another interesting step in the research that is being performed in the tissue engineering sphere. However there is a lot more research required before bioengineered tissues can be used for transplantation into humans

Sieg Holle's curator insight, February 16, 2014 11:23 AM

Towards our age of abundance and self sufficiency and personal choice?

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Lockheed Martin joins the world's largest wave-energy development project

Lockheed Martin joins the world's largest wave-energy development project | Amazing Science | Scoop.it

Lockheed Martin has joined a partnership to develop what it described as “the world’s largest wave energy project” to date, off the Victoria coast in southern Australia. Victorian Wave Partners Ltd. is an Australian special-purpose company owned by Ocean Power Technologies Australasia Pty Ltd., a developer of “wave energy” technology.


OPT’s PowerBuoy system uses a "smart" buoy to convert wave energy into electricity.  The buoy moves up and down with the rising and falling of waves, and the mechanical energy generated by this action drives an electrical generator, which transmits power to shore via an underwater cable.


The system is designed to be electrically tuned on a wave-by-wave basis to maximize the amount of electricity produced. In the Australian development, anticipated peak-power generating capacity is 62.5 megawatts. That would be sufficient to supply 10,000 homes.

The Victorian Wave project is scheduled to be built in three stages, with the first stage producing approximately 2.5 megawatts of peak power.

No starting date has been indicated for the installation.


Lockheed did not reveal the value of its investment.  It will provide overall project management, assist with the design for manufacturing the PowerBuoy systems, lead the production of selected components, and perform system integration of the wave energy converters.


Lockheed Martin’s participation in this project is reminiscent of Boeing’s recent participation in a tidal-energy project, though wave power is distinct from tidal power.


Wave power devices extract energy from the surface motion of ocean waves, which is very predictable and reportedly will generate electricity for more hours in a year than wind and solar sources.


"We are applying our design and system integration expertise to commercialize promising, emerging alternative energy technologies, including ocean power," stated Tim Fuhr, director of ocean energy for Lockheed Martin's Mission Systems and Training business. "This project extends our established relationship with OPT and Australian industry, and enables us to demonstrate a clean, efficient energy source for Australia and the world."

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How NASA is Planning to 3D Print Trees in Space

How NASA is Planning to 3D Print Trees in Space | Amazing Science | Scoop.it

The Stanford University researchers have been working long hours honing a three-dimensional printing process to make biomaterials like wood and enamel out of mere clumps of cells. Pundits say such 3D bioprinting has vast potential, and could one day be widely used to transform specially engineered cells into structural beams, food, and human tissue. Rothschild and Gentry don’t only see these laboratory-created materials helping only doctors and Mars voyagers. They also envision their specific research – into so-called “synthetic biomaterials” – changing the way products like good-old-fashioned wooden two-by-fours are made and used by consumers.


Here’s their plan: Rothschild, an evolutionary biologist who works for NASA and teaches astrobiology at Stanford, and Gentry, her doctoral advisee who is trained in biology and mechanical engineering, are working with $100,000 they received last fall from the space agency’s Innovative Advanced Concept Program. They say they’re on track to prove their concept  by October: a three-dimensional printing process that yields arrays of cells that can excrete non-living structural biomaterials like wood, mineral parts of bone and tooth enamel. They’re building a massive database of cells already in nature, refining the process of engineering select cells to make and then excrete (or otherwise deliver) the desired materials, and tweaking hardware that three-dimensionally prints modified cells into arrays that yield the non-living end products.


“Cells produce an enormous array of products on the Earth, everything from wool to silk to rubber to cellulose, you name it, not to mention meat and plant products and the things that we eat,” Rothschild said. “Many of these things are excreted (from cells). So you’re not going to take a cow or a sheep or a probably not a silk worm or a tree to Mars. But you might want to have a very fine veneer of either silk or wood. So instead of taking the whole organism and trying to make something, why couldn’t you do this all in a very precise way – which actually may be a better way to do it on Earth as well – so that you’re printing an array of cells that then can secrete or produce these products?”


Rothschild and Gentry’s setup is different from using basic 3D printers that deliver final products. Instead, the NASA-funded researchers are using 3D printing as an enabling technology of sorts. Their setup involves putting cells in a gelling solution with some sort of chemical signaling and support into a piezoelectric print head that spits out cells that form a gel-based 3D pattern.


Andrew Hessel, a biotechnology analyst who is a distinguished researcher with San Rafael, Calif.-based Autodesk Inc., said the emerging field of 3D bioprinting is a “pretty wide open space” with different researchers “all dancing on multiple fronts at once.” And the research is not without controversy. Information-technology research firm Gartner, Inc. recently predicted 3D printing of living tissue and organs will soon spur a major ethical debate.


Hessel said the most-complex 3D bioprinting research is being done with the actual engineering of cells. Companies like Organovo, for example, aren’t actually engineering the cells, and instead are differentiating and laying them in a way that they can mature and grow in to functional tissue.


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Miniaturized hearing aids that will fit into the ear canal

Miniaturized hearing aids that will fit into the ear canal | Amazing Science | Scoop.it
Fraunhofer researchers pack a total of 19 hearing-aid components (left) into their new microsystem (right). System-on-chip integrated circuit, high-frequency


The technology is also suitable for implants, pacemakers, and insulin pumps. This all means that the system uses only a fraction of the energy required by conventional devices, keeping cumbersome battery changes to a minimum. “Ideally, patients should not even be feeling of wearing the hearing aid over long periods of time,” says Dr. Dionysios Manessis from Fraunhofer Institute of Reliability and Microintegration IZM in Berlin.


With dimensions of just 4 mm by 4mm by 1 mm, the new microsystem is fifty times smaller than the current models. To achieve this, the project partners first developed especially small components such as innovative miniature antennas, system-on-chip integrated circuitry and high frequency filters, then integrated the 19 discrete components in a single module, using a modular 3D stacking concept that saves extra space.


Hearing aids worn behind the ear are powered by a 180mAh  (milliampere hour) battery, which must be either replaced or recharged approximately every two weeks. The aim is to minimize the system’s energy consumption to around one milliwatt (mW) to extend battery life up to 20 weeks.


The development is part of the EU WiserBAN project. Project partners are also looking to optimize energy management. The WiserBAN project partners are also developing special antenna and wireless protocols that can communicate information such as pulse, blood pressure, or glucose levels straight to a physician’s tablet or smartphone. The resulting WiserBAN wireless system makes obsolete the relay station — an extra device that patients have previously been obliged to wear to extend the communication range.


Another advantage is that the wireless protocols developed within the WiserBAN project are based on the reliable IEEE 802.15.4 and 802.15.6 standards. Conventional devices have ordinarily relied on Bluetooth, where there are often issues with interference with other devices.


It is hoped that the new technology will act as the springboard for more comfortable, more reliable healthcare products in the future — from long-term electrocardiography to insulin pumps. Furthermore, there is the potential to use the microsystem in implants and pacemakers.

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Mother's milk customized to sex of the baby

Mother's milk customized to sex of the baby | Amazing Science | Scoop.it
Mothers may say they don't care whether they have a son or a daughter, but their breast milk says otherwise.


"Mothers are producing different biological recipes for sons and daughters," says Katie Hinde, an evolutionary biologist at Harvard UniversityStudies in humans, monkeys and other mammals have found a variety of differences in both the content and the quantity of milk produced.


One common theme: baby boys often get milk that is richer in fat or protein — and thus energy — while baby girls often get more milk.

There are a lot of theories as to why this happens, says Hinde, who presented her findings at the American Association for the Advancement of Science's annual meeting.


Rhesus monkeys, for instance, tend to produce more calcium in the milk they feed to daughters who inherit social status from their mothers.

"It could be adaptive in that it allows mothers to give more milk to daughters which is going to accelerate their develop and allow them to begin reproducing at early ages," says Hinde.


Males don't need to reach sexual maturity as quickly as females because the only limit on how often they reproduce is how many females they can win over. "While the food aspects of milk to some extent are replicated in formula, the immunological factors and medicine of milk are not and the hormonal signals are not," she says.


Getting a better understanding of how milk is personalized for specific infants will also help hospitals find better matches for breast milk donated to help nourish sick and premature infants in neo natal units, she adds.

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IBM sets new speed record for Big Data

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

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


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


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


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


REFERENCES:



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Our brain has a switch board to guide behavior in response to external stimuli

Our brain has a switch board to guide behavior in response to external stimuli | Amazing Science | Scoop.it

How do our brains combine information from the external world (sensory stimulation) with information on our internal state such as hunger, fear or stress? NERF-scientists demonstrate that the habenula, a specific part in our brain consisting of neural circuits, acts as a gate for sensory information, thus regulating behavior in response to external stimuli. 


The medial habenula in the brain relays information from the sensory areas via the interpeduncular nucleus to the periaqueductal gray matter that regulates animal behavior under stress conditions. Ablation of the dorsal habenula (dHb) in zebrafish, which is equivalent to the mammalian medial habenula, perturbs experience-dependent fear. Therefore, understanding dHb function is important for understanding the neural basis of fear. In zebrafish, the dHb receives inputs from the mitral cells (MCs) of the olfactory bulb (OB), and odors can trigger distinct behaviors (e.g., feeding, courtship, alarm). However, it is unclear how the dHb processes olfactory information and how these computations relate to behavior. In this recent study, researchers demonstrated that the odor responses in the dHb are asymmetric and spatially organized despite the unorganized OB inputs. Moreover, they show that the spontaneous dHb activity is not random but structured into functionally and spatially organized clusters of neurons, which reflects the favored states of the dHb network. These dHb clusters are also preserved during odor stimulation and govern olfactory responses. Finally, they show that functional dHb clusters overlap with genetically defined dHb neurons, which regulate experience-dependent fear. Thus, the working hypothesis is that the dHb is composed of functionally, spatially, and genetically distinct microcircuits that regulate different behavioral programs.

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Bonobos, like humans, keep time to music, study shows

Bonobos, like humans, keep time to music, study shows | Amazing Science | Scoop.it

Some animals, like humans, can sense and respond to a musical beat, a finding that has implications for understanding how the skill evolved, scientists said. A study of bonobos, closely related to chimpanzees, shows they have an innate ability to match tempo and synchronize a beat with human experimenters. For the study, researchers designed a highly resonate, bonobo-friendly drum able to withstand 500 pounds of jumping pressure, chewing, and other ape-like behaviors.


“Bonobos are very attuned to sound. They hear above our range of hearing,” said Patricia Gray, a biomusic program director at University of North Carolina in Greensboro. Experimenters beat a drum at a tempo favored by bonobos – roughly 280 beats per minute, or the cadence that humans speak syllables. The apes picked up the beat and synchronized using the bonobo drum, Gray and psychologist Edward Large, with the University of Connecticut, said at the annual meeting of the American Association for the Advancement of Science.


“It’s not music, but we’re slowing moving in that direction,” Large said. Related research on a rescued sea lion, which has no innate rhythmic ability, shows that with training, it could bob its head in time with music, said comparative psychologist Peter Cook, who began working with Ronan the sea lion while a graduate student at the University of California, Santa Cruz.


Scientists suspect that the musical and rhythmic abilities of humans evolved to strengthen social bonds, “so, one might think that a common ancestor to humans and the bonobo would have some of these capabilities,” Large said. The addition of sea lions to the list suggests that the ability to sense rhythm may be more widespread.

Gray and Large said they would like to conduct a study on whether bonobos in the wild synchronize with other members of their species when they, for example, beat on hollow trees.


“That’s really coordination. Now, you’re talking about a social interaction,” Large said. “If your brain rhythms are literally able to synchronize to someone else’s brain rhythms, that’s what communication is potentially all about.”


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Chaohusaurus Fossil Shows Oldest Live Reptile Birth

Chaohusaurus Fossil Shows Oldest Live Reptile Birth | Amazing Science | Scoop.it

Recent excavations in south Majiashan, Anhui, China, yielded more than 80 new ichthyosaur skeletons. Among the specimens was a partial skeleton that contained embryos. According to Dr. Chen and colleagues, the fossil belongs to the ichthyosaur Chaohusaurus, which is the oldest of Mesozoic marine reptiles. This viviparous creature lived around 248 million years ago. It had a lizard-like appearance and was one of the smallest ichthyosaurs (up to 1.8 m long).


The new fossil was associated with three embryos and neonates: one inside the mother, another exiting the pelvis-with half the body still inside the mother-and the third outside of the mother. The headfirst birth posture of the second embryo indicates that live births in ichthyosaurs may have taken place on land, instead of in the water, as some studies have previously suggested.


“The study reports the oldest vertebrate fossil to capture the ‘moment’ of live-birth, with a baby emerging from the pelvis of its mother. The 248-million-year old fossil of an ichthyosaur suggests that live-bearing evolved on land and not in the sea,” said Dr Ryosuke Motani from the University of California, Davis, the first author of a paper published in the journal PLoS ONE.


The Chaohusaurus fossil may also contain the oldest fossil embryos of Mesozoic marine reptile, about 10 million years older than those indicated on previous records.


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The Ubi Ubiquitous Computer is Here: Talk to Your Wall and Your Wall will Talk Back

The Ubi Ubiquitous Computer is Here: Talk to Your Wall and Your Wall will Talk Back | Amazing Science | Scoop.it

The Ubi is a WiFi-connected, voice-operated computer that plugs into a power outlet and makes the environment around it Internet enabled. Reminiscent of voice controlled computers depicted in science fiction, early uses of the Ubi include Internet search, messaging, and communications without the use of hands or screens. The Ubi also includes sensors that allow for remote monitoring of the environment around it.

Project Ubi Odyssey will allow early adopters of technology to get access to the Ubi, develop connectivity with home automation and Internet services, and create novel human computer interactions. Those interested can register for the program at www.theubi.com and selected candidates will be invited to participate in the program. The Beta Ubi cost is $299. The program is currently limited to 5,000 participants and to residents of the United States.

The Ubi relies on powerful server technology that processes natural language to infer requests from the user and then pulls data from various Internet sources. Users can easily build voice-driven interactions and connect devices and services through the Ubi Portal. The device is equipped with temperature, humidity, air pressure and ambient light sensors to provide feedback on the environment around it. Also onboard the Ubi are stereo speakers, two microphones, and bright multi-colored LED indicator lights.


Unified Computer Intelligence Corporation CEO Leor Grebler told me the device will also be able to sense devices that are openly connected to the Internet (eventually, the Nest “learning” thermostat and smart smoke/CO2 alarms), “but we’re not controlling devices outright yet. We will add a way to talk to devices/Internet services as well as for them to talk back to the user.”


Here are the impressive specs: Android OS 4.1, 1.6 GHz Dual-Core ARM Cortex-A9 Processor, 1 GB RAM, 802.11 b/n/g Wifi Enabled (WPA and WPA2 encryption), stereo speakers and dual microphones, Bluetooth-capable, ambient light sensor, cloud-based speech recognition (Google/Android libraries), and natural language understanding.


And you can program its user interface on a computer, or verbally on the Ubi, Grebler said. “We’re slowly releasing apps on portal.theubi.com,” he said. “We have the first blossoms of an API that will essentially allow any Internet service, such as email, calendar, Twitter, Facebook, etc. ) to have its own voice and be interactive through the Ubi.”


You can register for the program at www.theubi.com and selected candidates will be invited to participate in the program. The Beta Ubi cost is $299. The program is currently limited to 5,000 participants and to U.S. residents.

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Tamika Garay's curator insight, March 25, 2015 11:24 PM

#4 Most Important Technologies in the next 5-10 years

Voice operated computers

 

Voice operated computers and operating systems have captured the imaginations of  sci-fi writers for years and have been included in recent works such as :

 

* Her (Movie, 2013 Director & Writer – Spike Jonze) - a movie about a man who falls in love with his interactive operating system.

 

* Extant (Series – 2014 Halle Berry) – there is a Siri-like talking computer device in every home and space station

 

Using voice commands to operate computers would make it more natural for humans to use by allowing the interface between user and computer become invisible. With the popularity of Siri and Google voice recognition, voice operated computers and operating systems will be important in the next 5-10 years.

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Quarks Know Their Left From Their Right

Quarks Know Their Left From Their Right | Amazing Science | Scoop.it

Matter interacts through four fundamental forces: the electromagnetic force that creates light and chemical bonds, the strong nuclear force that binds quarks and nuclei, the weak nuclear force that produces a type of radioactive decay called beta decay, and gravity. There could be other forces – some theorists have speculated that a second version of the weak force may also exist. At one time, physicists assumed that all the forces obeyed a handful of symmetries. So, for example, a physical system should behave exactly like its mirror image, a symmetry known as parity.


In 1957, physicists discovered that parity does not hold in particle interactions mediated by the weak force. For example, suppose you aim right-spinning electrons at nuclei and watch them bounce off. If you look at the tiny shooting gallery in a mirror, you'll see left-spinning electrons bouncing off the target. So if the interaction between electron and nucleus were mirror-symmetric, then the scattering of right- and left-spinning electrons should be the same. And, indeed, that’s exactly what would happen if the negatively charged electrons interacted with the positively charged nuclei only through the electromagnetic force.


But the electrons also interact with the nuclei through the weak force, which violates parity and is not mirror symmetric. As a result, right-spinning and left-spinning electrons ricochet off the target differently, creating a slight asymmetry in their scattering pattern. That effect was seen at SLAC National Accelerator Laboratory in Menlo Park, California, in 1978 in an experiment called E122 that helped cement physicists' then-emerging standard model. A second weak force, if it exists, ought to give similarly lopsided results.


But what about the quarks? Like electrons, they can spin one way or the other as they zip around inside protons and neutrons. And, according to the standard model, the right- and left-spinning quarks should interact slightly differently with an incoming electron, producing an additional asymmetry, or parity violation, when the spin of the incoming electrons is flipped. Now, Xiaochao Zheng, a nuclear physicist at the University of Virginia in Charlottesville, and colleagues have observed that smaller contribution, as they recently reported in Nature.


That was no mean feat. To see the extra asymmetry, the incoming electron must strike the nucleus hard enough to blast out a single quark, setting off a shower of particles, as was done in E122 but not in subsequent experiments. Researchers must take great care to ensure that they alternately shine equally intense beams of right- and left-spinning electrons on the target. Using the electron accelerator at Thomas Jefferson National Accelerator Facility in Newport News, Virginia, the researchers shined 170 billion electrons on a target of liquid deuterium over 2 months in 2009. After crunching the data, they were able to measure the part-in-10,000 scattering asymmetry precisely enough to pull out the contribution from the quarks, albeit with a large uncertainty. The result agrees with the standard model prediction.


"They've measured something fundamental at the quark level that wasn't measured before," says William Marciano, a theorist at Brookhaven National Laboratory in Upton, New York. Maas notes that the result is not as exciting as it could have been, however. "They have not observed any new physics at the level of their precision," he says. The new result does place tighter limits on models that assume a second weak force exists, Maas says.


The measurement is not the end of the road. The 101 members in the experimental team intend to repeat their measurement and hope to improve their precision by at least a factor of 5, Zheng says. That should enable them to test for new forces with far more sensitivity, she says. Marciano agrees that "this is just the first step." He notes that it might be beneficial that the asymmetry from the quarks is so small in the standard model, as that will make any deviation look relatively large.

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Scientists estimate 16,000 tree species in the Amazon

Scientists estimate 16,000 tree species in the Amazon | Amazing Science | Scoop.it
Researchers, taxonomists, and students from The Field Museum and 88 other institutions around the world have provided new answers to two simple but long-standing questions about Amazonian diversity: How many trees are there in the Amazon, and how many tree species occur there?


The vast extent and difficult terrain of the Amazon Basin (including parts of Brazil, Peru, Columbia) and the Guiana Shield (Guyana, Suriname, and French Guiana), which span an area roughly the size of the 48 contiguous North American states, has historically restricted the study of their extraordinarily diverse tree communities to local and regional scales. The lack of basic information about the Amazonian flora on a basin-wide scale has hindered Amazonian science and conservation efforts.


over 100 experts have contributed data from 1,170 forestry surveys in all major forest types in the Amazon to generate the first basin-wide estimates of the abundance, frequency and spatial distribution of thousands of Amazonian trees.


Extrapolations from data compiled over a period of 10 years suggest that greater Amazonia, which includes the Amazon Basin and the Guiana Shield, harbors around 390 billion individual trees, including Brazil nut, chocolate, and açai berry trees.


"We think there are roughly 16,000 tree species in Amazonia, but the data also suggest that half of all the trees in the region belong to just 227 of those species! Thus, the most common species of trees in the Amazon now not only have a number, they also have a name. This is very valuable information for further research and policymaking," says Hans ter Steege, first author on the study and researcher at the Naturalis Biodiversity Center in South Holland, Netherlands.


The authors termed these species "hyperdominants." While the study suggests that hyperdominants -- just 1.4 percent of all Amazonian tree species -- account for roughly half of all carbon and ecosystem services in the Amazon, it also notes that almost none of the 227 hyperdominant species are consistently common across the Amazon. Instead, most dominate a region or forest type, such as swamps or upland forests.


The study also offers insights into the rarest tree species in the Amazon. According to the mathematical model used in the study, roughly 6,000 tree species in the Amazon have populations of fewer than 1,000 individuals, which automatically qualifies them for inclusion in the International Union for Conservation of Nature (IUCN) Red List of Threatened Species. The problem, say the authors, is that these species are so rare that scientists may never find them.


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Out of this world first light images emerge as the Gemini Planet Imager in Chile goes online

Out of this world first light images emerge as the Gemini Planet Imager in Chile goes online | Amazing Science | Scoop.it

After nearly a decade of development, construction and testing, the world's most advanced instrument for directly imaging and analyzing planets orbiting around other stars is pointing skyward and collecting light from distant worlds. 

"Even these early first-light images are almost a factor of 10 better than the previous generation of instruments. In one minute, we were seeing planets that used to take us an hour to detect," says Bruce Macintosh of Lawrence Livermore National Laboratory, who led the team who built the instrument. 

For the past decade, Lawrence Livermore has been leading a multi-institutional team in the design, engineering, building and optimization of the instrument, called the Gemini Planet Imager (GPI), which will be used for high-contrast imaging to better study faint planets or dusty disks next to bright stars. Astronomers -- including a team at LLNL-- have made direct images of a handful of extrasolar planets by adapting astronomical cameras built for other purposes. GPI is the first fully optimized planet imager, designed from the ground up for exoplanet imaging deployed on one of the world's biggest telescopes, the 8-meter Gemini South telescope in Chile.


Gemini Planet Imager's first light image (see picture) of the light scattered by a disk of dust orbiting the young star HR4796A. This narrow ring is thought to be dust from asteroids or comets left behind by planet formation; some scientists have theorized that the sharp edge of the ring is defined by an unseen planet. The left image shows normal light, including both the dust ring and the residual light from the central star scattered by turbulence in the Earth's atmosphere. The right image shows only polarized light. Leftover starlight is unpolarized and hence removed from this image. The light from the back edge of the disk is strongly polarized as it scatters towards us.


Gemini's website: http://planetimager.org/

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Mechanical Overlords: AI Robots are Infiltrating Insect, Fish and Bird Communities and Take Control

Mechanical Overlords: AI Robots are Infiltrating Insect, Fish and Bird Communities and Take Control | Amazing Science | Scoop.it

Several years ago, a group of American cockroaches discovered four strangers in their midst. A brief investigation revealed that the interlopers smelled like cockroaches, and so they were welcomed into the cockroach community. The newcomers weren’t content to just sit on the sidelines, however. Instead, they began to actively shape the group’s behavior. Nocturnal creatures, cockroaches normally avoid light. But when the intruders headed for a brighter shelter, the rest of the roaches followed.


What the cockroaches didn’t seem to realize was that their new, light-loving leaders weren’t fellow insects at all. They were tiny mobile robots, doused in cockroach pheromones and programmed to trick the living critters into following their lead. The demonstration, dubbed the LEURRE project and conducted by a team of European researchers, validated a radical idea—that robots and animals could be merged into a “biohybrid” society, with biological and technological organisms forming a cohesive unit.


A handful of scientists have now built robots that can socially integrate into animal communities. Their goal is to create machines that not only infiltrate animal groups but also influence them, changing how fish swim, birds fly, and bees care for their young. If the research reaches the real world, we may one day use robots to manage livestock, control pests, and protect and preserve wildlife. So, dear furry and feathered friends, creepy and crawly creatures of the world: Prepare for a robo-takeover.

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