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  • richardmitnick 6:09 pm on March 4, 2019 Permalink | Reply
    Tags: “What is interesting” says first author Tatsuya Kaneko a postdoctoral researcher at the RIKEN Cluster for Pioneering Research “is that our calculations showed that this takes place based on the , But for the present study the researchers used non-equilibrium dynamics to analyze the effect of pulses of light on a Mott insulator and found that the effect would in fact happen in the real world, Mott insulators, RIKEN, Scientists from the RIKEN Cluster for Pioneering Research have shown that pulses of light could be used to turn these materials beyond simple conductors to superconductors—materials that conduct ele, , Thirty years ago the mathematical physicist Chen-Ning Yang originally proposed the idea of eta-pairing but because it was a purely mathematical concept it was understood as a virtual phenomenon that w, This process would happen through an unconventional type of superconductivity known as “eta pairing”, Under normal electron band theory they ought to conduct electricity but they do not due to interactions among their electrons, What remains is to perform actual experiments with Mott insulators to verify that this process actually takes place   

    From RIKEN: “Light pulses provide a new route to enhance superconductivity” 

    RIKEN bloc

    From RIKEN

    March 4, 2019

    Chief Scientist
    Seiji Yunoki
    Computational Condensed Matter Physics Laboratory
    Chief Scientist Laboratories

    Jens Wilkinson
    RIKEN International Affairs Division
    Tel: +81-(0)48-462-1225 / Fax: +81-(0)48-463-3687
    Email: pr@riken.jp

    1
    Schematic of eta-pairing

    Materials known as Mott insulators are odd things. Under normal electron band theory they ought to conduct electricity, but they do not, due to interactions among their electrons. But now, scientists from the RIKEN Cluster for Pioneering Research have shown that pulses of light could be used to turn these materials beyond simple conductors to superconductors—materials that conduct electricity without energy loss. This process would happen through an unconventional type of superconductivity known as “eta pairing.”

    Using numerical simulations, the researchers found that this unconventional type of conductivity, which is believed to take place under non-equilibrium conditions in strongly correlated materials such as high-Tc cuprates and iron-pnictides, arises due to a phenomenon known as eta pairing. This is different form the superconductivity observed in the same strongly correlated materials under equilibrium conditions, and is thought to involve repulsive interactions between certain electrons within the structure. It is also different from traditional superconductivity, where the phenomenon arises due to interactions between electrons and vibrations of the crystal structure, inducing mutual interactions between electrons through vibrations and thus overcoming the repulsion between the electrons.

    Thirty years ago, the mathematical physicist Chen-Ning Yang originally proposed the idea of eta-pairing, but because it was a purely mathematical concept, it was understood as a virtual phenomenon that would not take place in the real world. But for the present study, the researchers used non-equilibrium dynamics to analyze the effect of pulses of light on a Mott insulator, and found that the effect would in fact happen in the real world. “What is interesting,” says first author Tatsuya Kaneko, a postdoctoral researcher at the RIKEN Cluster for Pioneering Research, “is that our calculations showed that this takes place based on the beautiful mathematical structure that Yang and his followers formulated so many years ago.”

    According to Seiji Yunoki, who led the research team, “This work provides new insights not only into the phenomenon of non-equilibrium dynamics, but also could lead to the development of new high-temperature superconductors, which could be useful in applications. What remains is to perform actual experiments with Mott insulators to verify that this process actually takes place.”

    The research was published in Physical Review Letters.

    See the full article here .


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    Stem Education Coalition

    RIKEN campus

    RIKEN is Japan’s largest comprehensive research institution renowned for high-quality research in a diverse range of scientific disciplines. Founded in 1917 as a private research foundation in Tokyo, RIKEN has grown rapidly in size and scope, today encompassing a network of world-class research centers and institutes across Japan.

     
  • richardmitnick 5:02 pm on February 20, 2019 Permalink | Reply
    Tags: , , Brain clock ticks differently in autism, , RIKEN   

    From RIKEN: “Brain clock ticks differently in autism” 

    RIKEN bloc

    From RIKEN

    February 15, 2019
    Adam Phillips
    RIKEN International Affairs Division
    Tel: +81-(0)48-462-1225
    Fax: +81-(0)48-463-3687
    Email: pr@riken.jp

    The neural ‘time windows’ in certain small brain areas contribute to the complex cognitive symptoms of autism, new research suggests. In a brain imaging study of adults, the severity of autistic symptoms was linked to how long these brain areas stored information. The differences in neural timescales may underlie features of autism like hypersensitivity and could be useful as a future diagnostic tool.

    Sensory areas of the brain that receive input from the eyes, skin and muscles usually have shorter processing periods compared with higher-order areas that integrate information and control memory and decision-making. The new study, published in the journal eLife on February 5, shows that this hierarchy of intrinsic neural timescales is disrupted in autism. Atypical information processing in the brain is thought to underlie the repetitive behaviors and socio-communicational difficulties seen across the spectrum of autistic neurodevelopmental disorders (ASD), but this is one of the first indications that small-scale temporal dynamics could have an outsized effect.

    Magnetic resonance imaging of the brains of high-functioning male adults with autism were compared to those of people without autism. In the resting state, both groups showed the expected pattern of longer timescales in frontal brain areas linked to executive control, and shorter timescales in sensory and motor areas. “Shorter timescales mean higher sensitivity in a particular brain region, and we found the most sensitive neural responses in those individuals with the most severe autistic symptoms,” says lead author Takamitsu Watanabe of the RIKEN Center for Brain Science. One brain area that displayed the opposite pattern was the right caudate, where the neural timescale was longer than normal, particularly in individuals with more severe repetitive, restricted behaviors. These differences in brain activity were also found in separate scans of autistic and neurotypical children.

    The team of Japanese and UK researchers think that structural changes in small parts of the brain link these local dynamics to ASD symptoms. They found changes in grey matter volume in the areas with atypical neural timescales. A greater density of neurons can contribute to recurrent, repetitive neural activity patterns, which underlie the longer and shorter timescales observed in the right caudate and bilateral sensory/visual cortices, respectively. “The neural timescale is a measure of how predictable the activity is in a given brain region. The shorter timescales we observed in the autistic individuals suggest their brains have trouble holding onto and processing sensory input for as long as neurotypical people,” says Watanabe. “This may explain one prominent feature of autism, the great weight given by the brain to local sensory information and the resulting perceptual hypersensitivity.”

    See the full article here .


    five-ways-keep-your-child-safe-school-shootings

    stem

    Stem Education Coalition

    RIKEN campus

    RIKEN is Japan’s largest comprehensive research institution renowned for high-quality research in a diverse range of scientific disciplines. Founded in 1917 as a private research foundation in Tokyo, RIKEN has grown rapidly in size and scope, today encompassing a network of world-class research centers and institutes across Japan.

     
  • richardmitnick 1:36 pm on December 28, 2018 Permalink | Reply
    Tags: Hybrid qubits solve key hurdle to quantum computing, , RIKEN   

    From RIKEN: “Hybrid qubits solve key hurdle to quantum computing” 

    RIKEN bloc

    From RIKEN

    December 28, 2018

    Spin-based quantum computers have the potential to tackle difficult mathematical problems that cannot be solved using ordinary computers, but many problems remain in making these machines scalable. Now, an international group of researchers led by the RIKEN Center for Emergent Matter Science have crafted a new architecture for quantum computing. By constructing a hybrid device made from two different types of qubit—the fundamental computing element of quantum computers—they have created a device that can be quickly initialized and read out, and that simultaneously maintains high control fidelity.

    Quantum computing – IBM – the current state

    In an era where conventional computers appear to be reaching a limit, quantum computers—which do calculations using quantum phenomena—have been touted as potential replacements, and they can tackle problems in a very different and potentially much more rapid way. However, it has proven difficult to scale them up to the size required for performing real-world calculations.

    In 1998, Daniel Loss, one of the authors of the current study, came up with a proposal, along with David DiVincenzo of IBM, to build a quantum computer by using the spins of electrons embedded in a quantum dot—a small particle that behaves like an atom, but that can be manipulated, so that they are sometimes called “artificial atoms.” In the time since then, Loss and his team have endeavored to build practical devices.

    There are a number of barriers to developing practical devices in terms of speed. First, the device must be able to be initialized quickly. Initialization is the process of putting a qubit into a certain state, and if that cannot be done rapidly it slows down the device. Second, it must maintain coherence for a time long enough to make a measurement. Coherence refers to the entanglement between two quantum states, and ultimately this is used to make the measurement, so if qubits become decoherent due to environmental noise, for example, the device becomes worthless. And finally, the ultimate state of the qubit must be able to be quickly read out.

    While a number of methods have been proposed for building a quantum computer, the one proposed by Loss and DiVincenzo remains one of the most practically feasible, as it is based on semiconductors, for which a large industry already exists.

    For the current study, published in Nature Communications, the team combined two types of quits on a single device. The first, a type of single-spin qubit called a Loss-DiVincenzo qubit, has very high control fidelity—meaning that it is in a clear state, making it ideal for calculations, and has a long decoherence time, so that it will stay in a given state for a relatively long time before losing its signal to the environment.

    Unfortunately, the downside to these qubits is that they cannot be quickly initialized into a state or read out. The second type, called a singlet-triplet qubit, is quickly initialized and read out, but it quickly becomes decoherent. For the study, the scientists combined the two types with a type of quantum gate known as a controlled phase gate, which allowed spin states to be entangled between the qubits in a time fast enough to maintain the coherence, allowing the state of the single-spin qubit to be read out by the fast singlet-triplet qubit measurement.

    According to Akito Noiri of CEMS, the lead author of the study, “With this study we have demonstrated that different types of quantum dots can be combined on a single device to overcome their respective limitations. This offers important insights that can contribute to the scalability of quantum computers.”

    See the full article here .


    five-ways-keep-your-child-safe-school-shootings

    stem

    Stem Education Coalition

    RIKEN campus

    RIKEN is Japan’s largest comprehensive research institution renowned for high-quality research in a diverse range of scientific disciplines. Founded in 1917 as a private research foundation in Tokyo, RIKEN has grown rapidly in size and scope, today encompassing a network of world-class research centers and institutes across Japan.

     
  • richardmitnick 4:22 pm on May 29, 2018 Permalink | Reply
    Tags: , HAL QCD Collaboration, Japanese HAL llaboration are calling the particle di-Omega, , , RIKEN, Scientists have predicted a new type of dibaryon particle   

    From Riken and Science Alert: “Hunting the unseen – Scientists Are Hinting at The Existence of a Strange New Type of Particle” 

    RIKEN bloc

    From RIKEN

    July 15, 2011

    Sighting a theoretical exotic particle may become possible thanks to recently developed mathematical simulations.

    A better knowledge about the composition of sub-atomic particles such as protons and neutrons has sparked conjecture about, as yet, unseen particles. A tool based on theoretical calculations that could aid the search for these particles has been developed by a team of researchers in Japan called the HAL QCD Collaboration.

    Science paper from 2011
    Bound H Dibaryon in Flavor SU(3) Limit of Lattice QCD Physical Review Letters 20 April 2011

    At its most fundamental level, matter consists of particles known as quarks. Particle physicists refer to the six different types as ‘flavors’: up, down, charm, strange, top and bottom. The protons and neutrons found in the nucleus of an atom are examples of a class of particle called baryons: particles consisting of three quarks. Two baryons bound together are called dibaryons, but only one dibaryon has been found to date: a bound proton and neutron that has three up quarks and three down quarks in total.

    Models that reveal the potential physical properties of dibaryons, such as their mass and binding energy, are crucial if more of these particles are to be discovered in the future. To this end, the collaboration, including Tetsuo Hatsuda from the RIKEN Nishina Center for Accelerator-Based Science in Wako, developed simulations that shed new light on one promising candidate: the H dibaryon, which comprises two up, two down and two strange quarks (Fig. 1).

    1
    Figure 1: An artistic impression of a bound H dibaryon, a theoretical particle consisting of two up, two down and two strange quarks. © 2011 Keiko Murano

    The dynamics of quarks are described by an intricate theory known as quantum chromodynamics (QCD). The simulations, however, become increasingly difficult when more particles need to be included: dibaryons with six quarks are particularly testing. Hatsuda and his colleagues used an approach known as lattice QCD in which time and space are considered as a grid of discrete points. They simplified the calculation by assuming that all quarks have the same mass, but the strange quark is actually heavier than the up and down quarks. “We know from previous theoretical studies that the binding energy should be at its largest in the equal mass case,” says Hatsuda. “If we had not found a bound state in the equal mass case, there would be no hope that the bound state exists in the realistic unequal mass case.”

    The results from the collaboration’s simulations showed that the total energy of the dibaryon is less than the combined energy of two separate baryons, which verifies that H dibaryons are energetically stable. “We next hope to find the precise binding energy for unequal quark masses, which represents one of the major challenges in numerical QCD simulations,” Hatsuda adds.

    From Science Alerts 29 MAY 2018

    1
    (Keiko Murano/RIKEN) Science Alert 29 MAY 2018

    Using one of the most powerful computers in the world to perform complex simulations, scientists have predicted a new type of dibaryon particle – one that has two baryons instead of the usual one, with quarks all of the same colour.

    The researchers, from the Japanese HAL QCD Collaboration, are calling the particle di-Omega.

    Baryons are particles that contain three quarks, the subatomic particles that are one of the fundamental constituents that make up matter, and they make up most of the normal matter in the Universe. Protons and neutrons – which make up atomic nuclei – are baryons.

    The charge of baryons is dependent on the “colours,” or types, of the quarks inside, of which there are six – up, down, top, bottom, charm, and strange.

    In nature, there is only one known particle that’s made up of two baryons, or a dibaryon particle (also known as a hexaquark). It’s called deuteron, and it consists of a proton and a neutron bound together to form the nucleus of deuterium, or heavy hydrogen.

    Although scientists believe that other dibaryons might exist, so far none have been conclusively found.

    But by running simulations based on quantum chromodynamics (QCD), the theory that describes quark interactions, the HAL-QCD Collaboration is able to model potential stable dibaryons.

    But it’s not easy – the more quarks there are in the mix, the more complex their interactions, which means more computing power is needed.

    That’s why the researchers employed the K Computer at RIKEN’s Advanced Institute for Computational Science, which has a computational power of 10 petaflops, or 10 quadrillion operations per second.

    Riken Fujitsu K Computer at Riken Advanced Institute for Computational Science campus in Kobe, Hyōgo Prefecture, Japan

    Even so, it took almost three years to reach a conclusion on the particle. But reach a conclusion it did.

    Di-Omega consists of two Omega baryons, containing three strange quarks each. It is, the researchers said, the “most strange” of all the potential dibaryons.

    The research builds on the collaboration’s previous work – in 2011, they announced the discovery of a theoretical dibaryon with two up, two down and two strange quarks [above Riken article]. But since then they have refined their methods, devising a new theoretical framework, and a new algorithm, to allow for more efficient calculations.

    And, of course, the access to the K Computer, which became available for use by researchers in 2012, made an enormous difference.

    Going forward, the researchers believe their work can be applied to experimental settings to search for evidence of these particles in the real world.

    “We believe that these special particles could be generated by the experiments using heavy ion collisions that are planned in Europe and in Japan,” said quantum physicist Tetsuo Hatsuda of RIKEN.

    “We look forward to working with colleagues there to experimentally discover the first dibaryon system outside of deuteron.”

    This most recent work is also published in Physical Review Letters, Most Strange Dibaryon from Lattice QCD 23 May 2018

    See the full Riken article here .

    See the full Science Alert article here .


    five-ways-keep-your-child-safe-school-shootings

    stem

    Stem Education Coalition

    RIKEN campus

    RIKEN is Japan’s largest comprehensive research institution renowned for high-quality research in a diverse range of scientific disciplines. Founded in 1917 as a private research foundation in Tokyo, RIKEN has grown rapidly in size and scope, today encompassing a network of world-class research centers and institutes across Japan.

     
  • richardmitnick 1:28 pm on January 18, 2018 Permalink | Reply
    Tags: , , Fujitsu SPARC Riken K supercomputer, RIKEN, , Typhoon Soudelor   

    From Riken: “Geostationary satellite enables better precipitation and flood predictions” 

    RIKEN bloc

    RIKEN

    Using the power of Japan’s K computer, scientists from the RIKEN Advanced Institute for Computational Science and collaborators have shown that incorporating satellite data at frequent intervals—ten minutes in the case of this study—into weather prediction models can significantly improve the rainfall predictions of the models and allow more precise predictions of the rapid development of a typhoon.

    2
    No image caption or credit.

    1
    Fujitsu SPARC Riken K supercomputer

    Weather prediction models attempt to predict future weather by running simulations based on current conditions taken from various sources of data. However, the inherently complex nature of the systems, coupled with the lack of precision and timeliness of the data, makes it difficult to conduct accurate predictions, especially with weather systems such as sudden precipitation.

    As a means to improve models, scientists are using powerful supercomputers to run simulations based on more frequently updated and accurate data. The team led by Takemasa Miyoshi of AICS decided to work with data from Himawari-8, a geostationary satellite that began operating in 2015.

    3
    Himawari-8 geostationary satellite

    Its instruments can scan the entire area it covers every ten minutes in both visible and infrared light, at a resolution of up to 500 meters, and the data is provided to meteorological agencies. Infrared measurements are useful for indirectly gauging rainfall, as they make it possible to see where clouds are located and at what altitude.

    For one study, they looked at the behavior of Typhoon Soudelor (known in the Philippines as Hanna), a category 5 storm that wreaked damage in the Pacific region in late July and early August 2015. In a second study, they investigated the use of the improved data on predictions of heavy rainfall that occurred in the Kanto region of Japan in September 2015. These articles were published in Monthly Weather Review [N/A] and Journal of Geophysical Research: Atmospheres.

    3
    Simulation of Typhoon Soudelor at 22:00 on August 2, 2015

    For the study on Typhoon Soudelor, the researchers adopted a recently developed weather model called SCALE-LETKF—running an ensemble of 50 simulations—and incorporated infrared measurements from the satellite every ten minutes, comparing the performance of the model against the actual data from the 2015 tropical storm. They found that compared to models not using the assimilated data, the new simulation more accurately forecast the rapid development of the storm. They tried assimilating data at a slower speed, updating the model every 30 minutes rather than ten minutes, and the model did not perform as well, indicating that the frequency of the assimilation is an important element of the improvement.

    To perform the research on disastrous precipitation, the group examined data from heavy rainfall that occurred in the Kanto region in 2015. Compared to models without data assimilation from the Himawari-8 satellite, the simulations more accurately predicted the heavy, concentrated rain that took place, and came closer to predicting the situation where an overflowing river led to severe flooding.

    According to Miyoshi, “It is gratifying to see that supercomputers along with new satellite data, will allow us to create simulations that will be better at predicting sudden precipitation and other dangerous weather phenomena, which cause enormous damage and may become more frequent due to climate change. We plan to apply this new method to other weather events to make sure that the results are truly robust.”

    See the full article here .

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    RIKEN campus

    RIKEN is Japan’s largest comprehensive research institution renowned for high-quality research in a diverse range of scientific disciplines. Founded in 1917 as a private research foundation in Tokyo, RIKEN has grown rapidly in size and scope, today encompassing a network of world-class research centers and institutes across Japan.

     
  • richardmitnick 9:23 am on December 16, 2017 Permalink | Reply
    Tags: , , RIKEN, Superradiance of an ensemble of nuclei excited by a free electron laser,   

    From RIKEN: “Superradiance of an ensemble of nuclei excited by a free electron laser” 

    RIKEN bloc

    RIKEN

    December 15, 2017

    Contact

    Chief Scientist
    Alfred Baron
    Materials Dynamics Laboratory
    Photon Science Research Division
    RIKEN SPring-8 Center

    Jens Wilkinson
    RIKEN International Affairs Division
    Tel: +81-(0)48-462-1225 / Fax: +81-(0)48-463-3687
    Email: pr@riken.jp

    1
    Superradiance
    The figure shows photon emissions from 57Fe atoms. The chart shows that as the number of atoms increases from 1 to 5 to 20, the time until the first emission increases, while the energy of the photons increases.

    2
    Measuring the multi-photon emission after a single pulse of XFEL.
    a, Scope traces from the avalanche photo diode (APD) detectors after one pulse of 44 photons and the fits used to analyse the distribution. b, The distribution of multi-photon events measured in the APD detectors, as compared with a model incorporating a coherent source with few modes (M = 2.2) and an incoherent source (large M limit).

    3
    Acceleration of the initial decay rate.
    The increase of the initial decay rate for the transitions from N to N-1 excited states revealed (a) by the accelerated decay of the first out of N detected photon, PN1(t) (b) by the ratios PN1(t)/P11(t) of these data to the single-photon decay P11(t) (shown in (c)), and (d) by the estimated acceleration rates (PN1/ P11)|t→0. The solid lines in (a, b) are the calculations based on the statistical approach. The solid line in (d) is the power fit.

    A collaboration of scientists from five of the world’s most advanced x-ray sources in Europe, Japan and the US, has succeeded in verifying a basic prediction of the quantum-mechanical behavior of resonant systems. In the study published in Nature Physics, they were able to carefully follow, one x-ray at a time, the decay of nuclei in a perfect crystal after excitation with a flash of x-rays from the world’s strongest pulsed source, the SACLA x-ray free electron laser in Harima, Japan. They observed a dramatic reduction of the time taken to emit the first x-ray as the number of x-rays increased. This behavior is in good agreement with one limit of a superradiant system, as predicted by Robert H. Dicke in 1954.

    Dicke predicted that, in the same way that a large collection of bells will act differently from a single bell that is tapped, a group of atoms will emit light in response to excitation at a different rate—faster—than a single atom. He predicted a “superradiant” state, where, when large numbers of photons or quanta are put into a system with many atoms, the decay becomes much faster than for a single atom in isolation. Taking the analogy of bells, he was suggesting that if you have a large number of bells that you excite together, they can ring loudly, but the sound dies out much more quickly than the gentle fading of a single bell. His approach included quantum effects, predicting that the fastest decay occurred when the number of quanta was half the number of atoms.

    The concept of superradiance has since been verified, and, indeed, is a touchstone in the field of quantum optics. However, Dicke also predicted that a very strong change in decay rate would occur even when the number of quanta in the system was much less than the number of atoms in the system. This is what was investigated in the recent experiments at SACLA and the European Synchrotron Radiation Facility (ESRF) in France.

    SACLA Free-Electron Laser Riken Japan


    ESRF. Grenoble, France

    The new work replaced the low-energy quanta envisioned by Dicke with high-energy x-rays, allowing the researchers to follow the decay of the system one quantum—meaning one x-ray—at a time. However, getting strong pulses of x-rays is much harder than for low energy light, and required using the most modern sources, x-ray free electron lasers. These sources have only become available recently, and of the few operating in the world, only one, SACLA, at the RIKEN SPring-8 Center in Japan, achieves the required high energy. Using this source an international team of researchers from the ESRF in France, SPring-8 in Japan, DESY in Germany, the APS in the USA, and the Kurchatov Institute in Russia, were able to precisely follow the decay for up to 68 x-ray photons.


    ANL/APS

    They observed the accelerated emission of the first photon to be in excellent agreement with Dicke’s prediction. The single-photon decay under the same experimental conditions was studied at the ESRF.

    According to Alfred Baron of the RIKEN SPring-8 Center, “Through this work, we were able to demonstrate Dicke’s work to be correct, and were also able to offer an alternative picture of the decay properties, based on a statistical approach. This will be valuable for understanding future work.”

    See the full article here .

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    RIKEN campus

    RIKEN is Japan’s largest comprehensive research institution renowned for high-quality research in a diverse range of scientific disciplines. Founded in 1917 as a private research foundation in Tokyo, RIKEN has grown rapidly in size and scope, today encompassing a network of world-class research centers and institutes across Japan.

     
  • richardmitnick 6:01 pm on November 27, 2017 Permalink | Reply
    Tags: , CERN BASE experiment, , Penning traps, Physicists Just Smashed a Record For Measuring a Fundamental Proton Feature, , RIKEN, , The most exact measurement of the magnetic moment of protons   

    From Science Alert: “Physicists Just Smashed a Record For Measuring a Fundamental Proton Feature” 

    ScienceAlert

    Science Alert

    27 NOV 2017
    BRAD BERGAN

    1
    (Quality Stock Arts/Shutterstock.com)

    An international team of scientists employed highly precise methods to uncover the most exact measurement of the magnetic moment of protons.

    They found it to be 2.79284734462, plus-or-minus 0.00000000082 nuclear magnetons (the typical unit for measuring this property).

    The magnetic moment is a property of particles that is a prerequisite for magnetism, and applied to protons, it embodies a fundamental property of atomic structure.

    The team included scientists from RIKEN’s Ulmer Fundamental Symmetries Laboratory (FSL), Johannes Gutenberg-Universität Mainz, Max Planck Institute for Nuclear Physics, Heidelberg, and GSI Darmstadt.

    The level of precision for the first-of-a-kind measurements was better than one part per billion.

    In order to achieve this kind of specificity, researchers needed to isolate a single proton.

    Not a microscopic handful or an iota of particles; just one, caught in a Penning trap.

    1
    A Penning trap. Image Credit: RIKEN

    They detected the thermal signal of ions (atoms or molecules with an uneven ratio of electrons to protons) and used an electric field to eliminate protons until there was only one left.

    Achieving the high level of specificity for the experiment required both extremely difficult engineering and moving the proton between two types of traps.

    A proton inside a Penning trap will sync its spin with the magnetic field inside the trap. The detector measured two frequencies: the cyclotron frequency of the proton in a magnetic field and the Larmor (spin-procession) frequency.

    Together, these help determine the magnetic moment. After the proton goes through all that in the first trap, it moves to a second trap, where its spin state is obtained with a magnetic bottle.

    Georg Schneider, first author of the study [Science], says the work will “allow us to get a better understanding of, for example, atomic structure.” Andreas Mooser, member of RIKEN FSL and second author of the study, said.

    “Looking forward, using this technique, we will be able to make similarly precise measurements of the antiproton at the BASE experiment in CERN, and this will allow us to look for further hints for why there is no antimatter in the universe today.”

    CERN BASE experiment

    See the full article here .

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  • richardmitnick 8:33 am on July 7, 2017 Permalink | Reply
    Tags: , , , RIKEN   

    From RIKEN: “Visualizing whole-body cancer metastasis at the single-cell level” 

    RIKEN bloc

    RIKEN

    July 6, 2017
    Adam Phillips
    RIKEN International Affairs Division
    Tel: +81-(0)48-462-1225 /
    Fax: +81-(0)48-463-3687
    pr@riken.jp

    1
    3D analysis of the metastatic patterns in experimental brain metastasis models

    Researchers at the RIKEN Quantitative Biology Center (QBiC) and the University of Tokyo (UTokyo) have developed a method to visualize cancer metastasis in whole organs at the single-cell level. Published in Cell Reports, the study describes a new method that combines the generation of transparent mice with statistical analysis to create 3-D maps of cancer cells throughout the body and organs.

    Recent research in optical clearing methods has made it possible to transparentize the bodies and organs of experimental animals. This has led to a new wave of anatomical studies that can combine tissue transparency with sophisticated cell-labeling techniques and light microscopy. Led by Hiroki Ueda at RIKEN QBiC/UTokyo and Kohei Miyazono at the UTokyo, the team has focused their efforts on being able to visualize and profile cancer metastasis throughout the body.

    “One of the biggest difficulties in studying cancer,” explains co-senior author Ueda, “is that tumor metastasis is started by just a few metastasized cells. Our new method makes it possible to image the whole body down to the individual cell level, and therefore we can detect cancer at spatial resolutions beyond what is possible using other current imaging techniques.”

    See the full article here .

    Please help promote STEM in your local schools.

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    RIKEN campus

    RIKEN is Japan’s largest comprehensive research institution renowned for high-quality research in a diverse range of scientific disciplines. Founded in 1917 as a private research foundation in Tokyo, RIKEN has grown rapidly in size and scope, today encompassing a network of world-class research centers and institutes across Japan.

     
  • richardmitnick 3:33 pm on June 27, 2017 Permalink | Reply
    Tags: , , , , , MPA, , RIKEN,   

    From Max Planck Institute for Astrophysics, Garching: “Neutrinos as drivers of supernovae” 

    Max Planck Institute for Astrophysics, Garching

    June 26, 2017
    Dr. Hans-Thomas Janka
    Max Planck Institute for Astrophysics, Garching
    Phone:+49 89 30000-2228
    Fax:+49 89 30000-2235
    thj@mpa-garching.mpg.de

    Dr. Hannelore Hämmerle
    Max Planck Institute for Astrophysics, Garching
    Phone:+49 89 30000-3980
    hhaemmerle@mpa-garching.mpg.de

    1
    Time evolution of the radioactive 56Ni in the ejecta of a 3D simulation of a neutrino-driven supernova explosion. The images show the non-spherical distribution from shortly after the onset of the explosion (3.25 seconds) until a late time (6236 seconds) when the final asymmetry is determined. The colours represent radial velocities according to the scales given for each panel. © MPA

    Radioactive elements in gaseous supernova remnant Cassiopeia A provide glimpses into the explosion of massive stars.

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    Cassiopeia A. NASA/CXC/SAO

    NASA/Chandra Telescope

    Stars exploding as supernovae are the main sources of heavy chemical elements in the Universe. In these star explosions, radioactive atomic nuclei are synthesized in the hot, innermost regions during the explosion and can thus provide insights into the unobservable physical processes that initiate the blast. Using elaborate computer simulations, a team of researchers from the Max Planck Institute for Astrophysics (MPA) and the research institute RIKEN in Japan were able to explain the recently measured spatial distributions of radioactive titanium and nickel in Cassiopeia A, a roughly 340 year old gaseous remnant of a nearby supernova.

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    The computer models yield strong support for the theoretical idea that such stellar death events can be initiated and powered by neutrinos escaping from the neutron star left behind at the origin of the explosion.

    Massive stars end their lives in gigantic explosions, so-called supernovae. Within millions of years of stable evolution, these stars have built up a central core composed of mostly iron. When the core reaches about 1.5 times the mass of the Sun, it collapses under the influence of its own gravity and forms a neutron star. Enormous amounts of energy are released in this catastrophic event, mostly by the emission of neutrinos. These nearly massless elementary particles are abundantly produced in the interior of the new-born neutron star, where the density is higher than in atomic nuclei and the temperature can reach 500 billion degrees Kelvin.

    The physical processes that trigger and drive the explosion have been an unsolved puzzle for more than 50 years. One of the theoretical mechanisms proposed invokes the neutrinos, because they carry away more than hundred times the energy needed for a typical supernova. Leaking out from the hot interior of the neutron star, a small fraction of the neutrinos are absorbed in the surrounding gas. This heating causes violent motions of the gas, similar to those in a pot of boiling water on a stove. When the bubbling of the gas becomes sufficiently powerful, the supernova explosion sets in as if the lid of the pot were blown off. The outer layers of the dying star are expelled into circumstellar space, and with them all the chemical elements that the star has assembled by nuclear burning during its life. But also new elements are created in the hot ejecta of the explosion, among them radioactive species such as 44Ti (titanium with 22 protons and 22 neutrons in its atomic nuclei) and 56Ni (28/28 neutrons/protons), which decay to stable calcium and iron, respectively. The thus released radioactive energy makes a supernova shine bright for years.

    3
    Observed distribution of 44Ti (blue) and iron (white, red) in Cassiopeia A. The visible iron is mostly the radioactive decay product of 56Ni. The yellow cross marks the geometrical centre of the explosion, the white cross and the arrow indicate the current location and the direction of motion of the neutron star. © Macmillan Publishers Ltd: Nature; from Grefenstette et al., Nature 506, 339 (2014); Fe distribution courtesy of U.~Hwang.)

    Because of the wild boiling of the neutrino-heated gas, the blast wave starts out non-spherically and imprints a large-scale asymmetry on the ejected stellar matter and the supernova as a whole, in agreement with the observation of clumpiness and asymmetries in many supernovae and their gaseous remnants. The initial asymmetry of the explosion has two immediate consequences. On the one hand, the neutron star receives a recoil momentum opposite to the direction of the stronger explosion, where the supernova gas is expelled with more violence. This effect is similar to the kick a rowing boat receives when a passenger jumps off. On the other hand, the production of heavy elements from silicon to iron, in particular also of 44Ti and 56Ni, is more efficient in directions where the explosion is stronger and where more matter is heated to high temperatures. “We have predicted both effects some years ago by our three-dimensional (3D) simulations of neutrino-driven supernova explosions”, says Annop Wongwathanarat, researcher at RIKEN and lead author of the corresponding publication of 2013, at which time he worked at MPA in collaboration with his co-authors H.-Thomas Janka and Ewald Müller. “The asymmetry of the radioactive ejecta is more pronounced the larger the neutron star kick is”, he adds. Since the radioactive atomic nuclei are synthesized in the innermost regions of the supernova, in the very close vicinity of the neutron star, their spatial distribution reflects explosion asymmetries most directly.

    New observations of Cassiopeia A (Cas A), the gaseous remnant of a supernova whose light reached the Earth around the year 1680, could meanwhile confirm this theoretical prediction. Because of its young age and relative proximity at a distance of just 11,000 light years, Cas A offers two great advantages for the measurements. First, the radioactive decay of 44Ti is still an efficient energy source, and the presence of this atomic nucleus can therefore be mapped in 3D with high precision in the whole remnant by detecting the high-energy X-ray radiation from the radioactive decays. Second, also the velocity of the neutron star is known with its magnitude and its direction on the plane of the sky.

    4
    Observable radioactive nickel (56Ni, green) and titanium (44Ti, blue) as predicted by the 3D simulation of a neutrino-driven supernova explosion shown in Fig. 1. The orientation is optimized for closest possible similarity to the Cas A image of Fig. 2a. The neutron star is marked by a white cross and shifted away from the centre of the explosion (red plus symbol) because of its kick velocity. The neutron star motion points away from the hemisphere that contains most of the ejected 44Ti. Iron of its kick velocity. The neutron star motion points away from the hemisphere that contains most of the ejected 44Ti. Iron (the decay product of Ni56) can be observed only in an outer, hot shell of Cas A. © MPA

    Since the neutron star propagates with an estimated speed of at least 350 kilometres per second, the asymmetry in the spatial distribution of the radioactive elements is expected to be very pronounced. Exactly this is seen in the observations . While the compact remnant speeds toward the lower hemisphere, the biggest and brightest clumps with most of the 44Ti are found in the upper half of the gas remnant. The computer simulation, viewed from a suitably chosen direction, exhibits a striking similarity to the observational image. But not only the spatial distributions of titanium and iron resemble those in Cas A (for a 3D visualization, see Fig. 3 in comparison with the 3D imaging of Cas A available at the weblink http://3d.si.edu/explorer?modelid=45). Also the total amounts of these elements, their expansion velocities, and the velocity of the neutron star are in amazing agreement with those of Cas A. “This ability to reproduce basic properties of the observations impressively confirms that Cas A may be the remnant of a neutrino-driven supernova with its violent gas motions around the nascent neutron star”, concludes H.-Thomas Janka.

    But more work is needed to finally prove that the explosions of massive stars are powered by energy input from neutrinos. “Cas A is an object of so much interest and importance that we must also understand the spatial distributions of other chemical species such as silicon, argon, neon, and oxygen”, remarks Ewald Müller, pointing to the beautiful multi-component morphology of Cas A revealed by 3D imaging (see http://3d.si.edu/explorer?modelid=45). One example is also not enough for making a fully convincing case. Therefore the team has joined a bigger collaboration to test the theoretical predictions for neutrino-driven explosions by a close analysis of a larger sample of young supernova remnants. Step by step the researchers thus hope to collect evidence that is able to settle the long-standing problem of the supernova mechanism.

    See the full article here .

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  • richardmitnick 9:17 am on December 31, 2015 Permalink | Reply
    Tags: , , RIKEN   

    From RIKEN: “A treasure trove of new cancer biomarkers” 

    RIKEN bloc

    RIKEN

    [This post is dedicated to EBM, Cancer researcher. I hope he sees it.]

    November 10, 2015 [I just started following RIKEN]
    Jens Wilkinson
    RIKEN Global Relations and Research Coordination Office
    Tel: +81-(0)48-462-1225 / Fax: +81-(0)48-463-3687
    Email: pr@riken.jp

    Biomarkers, which allow diseases to be diagnosed and staged based on relatively non-invasive blood tests, have been identified for several types of cancers, but for most cancers remain elusive. Now, research conducted at the RIKEN Center for Life Science Technologies (CLST) in Japan and the Harry Perkins Institute of Medical Research in Australia has identified a large number of genes that are upregulated in many different types of cancer, opening the door for developing biomarker tests that could be used to detect cancers early, allowing for prompt treatment.

    The study, published on November 9 in Cancer Research, made use of two different technologies. First, the team looked at data generated by CAGE technology that was developed at RIKEN as part of the FANTOM project.

    Temp 1

    Temp 2

    They examined RNA expression profiles of 225 cancer cell lines and 339 normal cells, and looked for differences in gene expression. They then supplemented this by looking at RNA sequencing data from 4,055 primary tumors and 563 healthy tissues from the Cancer Genome Atlas (TCGA) database, and crossed the two to identify changes that were found in both datasets.

    According to Bogumil Kaczkowski of CLST, the first author of the paper, “Using the two different datasets allowed us to make use of the strengths of each. The TCGA data is complicated by the fact that tumor samples are composed of mixture of different cells, while the FANTOM5 CAGE data is from cells grown in cell culture where changes might arise from the culture process. By putting the two together and looking at changes found in both, we have been able to make a robust catalog.”

    Based on the work, the researchers were able to identify 128 markers that were consistently perturbed in both datasets in a variety of tumor types. Some of them, such as TOP2A and MKI67, are well-known targets as potential biomarkers. But thanks to the data from FANTOM5, they were also able to find a number of new markers including non-coding RNAs, RNAs derived from repetitive elements and enhancer elements that CAGE technology can identify. In particular, they found that a little known repetitive element called REP522, was upregulated in many cancers.

    According to Piero Carninci, one of the leaders of the FANTOM5 consortium and an author of the paper, “The study shows that our CAGE (Cap-Analysis Gene Expression) technology is a powerful tool for cancer marker discovery at the promoter level. We found hundreds of promoters—parts of the genome that initiate expression of a gene—that are upregulated in cancer, and in particular, promoters that overlap with repetitive elements in the genome seem to be upregulated. This is an interesting insight into the development of cancer. We are especially interested in the REP522 element, and would like to determine what role it plays.”

    Carninci continues, “It is very rewarding to see that our basic science approach to mapping and understanding regulatory elements of the genome can be translated into discovery that can aid early cancer diagnosis. We hope that researchers will use our findings to identify markers for the many cancer types that currently have no useful markers. It may also be possible to target the genes we have identified as potential drug targets. These targets could potentially help many cancer patients as they are up-regulated in many different types of tumors.”
    Reference

    Kaczkowski B. et al. Transcriptome analysis of recurrently deregulated genes across multiple cancers identifies new pan-cancer biomarkers. Cancer Research http://dx.doi.org/ 10.1158/0008-5472.CAN-15-0484

    See the full article here .

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    RIKEN is Japan’s largest comprehensive research institution renowned for high-quality research in a diverse range of scientific disciplines. Founded in 1917 as a private research foundation in Tokyo, RIKEN has grown rapidly in size and scope, today encompassing a network of world-class research centers and institutes across Japan.

     
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