A theoretical model of DNA as a polymer explains why chemical markers on genes can survive from one cell generation to the next.

[Phys. Rev. X 6, 041047] Published Fri Dec 09, 2016

]]>Controlling a material’s electronic characteristics has long been a goal of physicists. A new study shows how strain and magnetization affect the transport properties of Weyl and Dirac semimetals, which can be thought of as cousins of graphene.

[Phys. Rev. X 6, 041046] Published Mon Dec 05, 2016

]]>The battle to improve measurement precision constantly forces scientists to develop more and more sophisticated methods. Surprisingly, theoretical demonstration shows that identical bosons, even when prepared in a random and noisy quantum state, can be used to attain precision surpassing that of classical statistics.

[Phys. Rev. X 6, 041044] Published Fri Dec 02, 2016

]]>Iron-based materials often exhibit magnetism, superconductivity, and nematic order. A theoretical investigation looks at the interplay between magnetism and orbital order and how these properties affect superconductivity.

[Phys. Rev. X 6, 041045] Published Fri Dec 02, 2016

]]>Electron-electron interactions are responsible for superconductivity, a state in which current flows without resistance. Researchers show that electron-electron interactions can be tuned at an oxide interface.

[Phys. Rev. X 6, 041042] Published Thu Dec 01, 2016

]]>Qubits are necessary for next-generation quantum computers. Researchers theoretically demonstrate a topological fluid of photons to simulate such qubits.

[Phys. Rev. X 6, 041043] Published Thu Dec 01, 2016

]]>Cold atomic gases exhibit a phononic analog of the Lamb shift, in which energy levels shift in the presence of the quantum vacuum.

[Phys. Rev. X 6, 041041] Published Mon Nov 28, 2016

]]>A key aspect of the standard model is the fact that quarks or gluons are not observed by themselves in nature. Scientists simulate, in one spatial dimension, the string breaking responsible for keeping these particles in pairs.

[Phys. Rev. X 6, 041040] Published Wed Nov 23, 2016

]]>Unexpected forms of proximity-induced superconductivity can result from magnetization developing a “twist.” Researchers demonstrate the noncollinear magnetic structure of a nanometer-scale stack of two metallic oxides.

[Phys. Rev. X 6, 041038] Published Tue Nov 22, 2016

]]>Experiments with ultracold magnetic atoms reveal liquid-like quantum droplets that are 20 times larger than previously observed droplets.

[Phys. Rev. X 6, 041039] Published Tue Nov 22, 2016

]]>Turbulence is inherent in both nature and industrial mixing applications. Numerical simulations shows how particles of different mass diffuse in a rotating medium.

[Phys. Rev. X 6, 041036] Published Mon Nov 21, 2016

]]>Target search processes can be found in a variety of fields spanning animal science, disease spreading, geophysics, and molecular signaling in biology. A theoretical analysis of the distribution of particles arriving at a target a certain distance away from their origin is presented.

[Phys. Rev. X 6, 041037] Published Mon Nov 21, 2016

]]>A significant challenge facing quantum computation is noise, and current theory proposes that it is surmountable if it is sufficiently weak and also weakly correlated in space and time. Now, researchers theoretically show that quantum computation can be achieved even when noise with arbitrary time correlations is present.

[Phys. Rev. X 6, 041034] Published Fri Nov 18, 2016

]]>Quantum computing relies on realizing on-chip communication channels. Researchers propose a method to connect defect clusters in diamond at room temperature to enable information exchange.

[Phys. Rev. X 6, 041035] Published Fri Nov 18, 2016

]]>Packing particles into a confined space is a feature of geological and industrial processes. A numerical investigation of the densest ways to pack aspherical particles may hold clues about the structure of granular piles.

[Phys. Rev. X 6, 041032] Published Thu Nov 17, 2016

]]>Entanglement, a key aspect of quantum mechanics, is critical to quantum information theory. Researchers theoretically show how cold atoms can be manipulated to measure the entanglement spectrum of a many-body quantum state.

[Phys. Rev. X 6, 041033] Published Thu Nov 17, 2016

]]>Researchers determine how the steady states of a quantum system with multiple such states depend on the initial properties of the system.

[Phys. Rev. X 6, 041031] Published Wed Nov 16, 2016

]]>An object can be commonly thought of as rigid or floppy. Now, scientists design and build periodic gear assemblies that can have topological floppy modes.

[Phys. Rev. X 6, 041029] Published Tue Nov 08, 2016

]]>Generating pure proton beams using lasers for novel cancer therapies has long challenged researchers. In a new experiment, scientists irradiate a thin hydrogen ribbon with a high-power laser to generate a large and pure population of protons.

[Phys. Rev. X 6, 041030] Published Tue Nov 08, 2016

]]>Light-matter interactions on the level of single photons will be important in next-generation communications and electronic devices. A new experiment shows how a confined electron can repeatedly emit a microwave photon.

[Phys. Rev. X 6, 041027] Published Mon Nov 07, 2016

]]>Coherence is a fundamental feature of quantum theory and promises to underpin many future quantum technologies. By studying processes where it is not a necessary resource, researchers sharpen the theory of coherence finding links with interferometry and quantum correlations.

[Phys. Rev. X 6, 041028] Published Mon Nov 07, 2016

]]>Devices in which photons are naturally protected both against internal losses and backscattering would be valuable for amplifying quantum signals. A new approach proposes an amplifier where such protection is present and has a topological origin.

[Phys. Rev. X 6, 041026] Published Tue Nov 01, 2016

]]>Nematic liquid crystals are widely used in the electronics industry. The variety of possible forms of nematic liquid crystals are investigated using techniques borrowed from high-energy physics.

[Phys. Rev. X 6, 041025] Published Mon Oct 31, 2016

]]>Friction plays a key role in everyday life. A new study shows that frictional resistance depends on the geometry of the bodies in frictional contact.

[Phys. Rev. X 6, 041023] Published Fri Oct 28, 2016

]]>High-precision quantum measurements often require signal amplification. A new technique shows how weak electromagnetic signals can be both amplified and modulated in frequency.

[Phys. Rev. X 6, 041024] Published Fri Oct 28, 2016

]]>In certain materials, mechanical strain can mimic the effects of real electromagnetic fields. A theoretical examination explores how Dirac and Weyl semimetals respond to both torsional and unidirectional strain.

[Phys. Rev. X 6, 041021] Published Thu Oct 27, 2016

]]>Many networks—electronic, physical, or biological—have mutually shared vulnerabilities that render them significantly less secure and robust. Now, the conditions necessary for secure connectivity within a network characterized by vulnerabilities affecting many nodes are calculated

[Phys. Rev. X 6, 041022] Published Thu Oct 27, 2016

]]>Spin-orbit interactions are responsible for intriguing phenomena such as topological insulating states. Now, scientists study the spin-orbit interactions of electrons directly at the interface between graphene and transition-metal dichalcogenides.

[Phys. Rev. X 6, 041020] Published Wed Oct 26, 2016

]]>Lenses are critical to a variety of fields of science, but optical aberrations such as astigmatism are common problems. A “perfect” lens made of two metasurfaces is theoretically developed.

[Phys. Rev. X 6, 041018] Published Tue Oct 25, 2016

]]>Many copper-based materials exhibit coupling between their electrons and excitations known as phonons. Now, researchers demonstrate a tool to accurately study the details of this coupling.

[Phys. Rev. X 6, 041019] Published Tue Oct 25, 2016

]]>The second law of thermodynamics is concerned with what state formations are allowed by nature. Now, drawing inspiration from quantum information theory, researchers show that for microscopic or quantum systems, one can perform an outlawed state transformation.

[Phys. Rev. X 6, 041016] Published Mon Oct 24, 2016

]]>The second law of thermodynamics plays an important role in both everyday life—think of hot coffee cooling off—and a range of scientific disciplines. Now, researchers prove a more accurate version of the second law, which states precisely by how much the hot coffee cools off, as well as being relevant to small quantum systems.

[Phys. Rev. X 6, 041017] Published Mon Oct 24, 2016

]]>Observational astronomy devoted to the detection of ripples in spacetime was born in 2015 with the first detection of gravitational waves. Now, researchers use updated complete spin models to estimate the black hole component masses of the objects involved in the GW150914 coalescence event.

[Phys. Rev. X 6, 041014] Published Fri Oct 21, 2016

]]>Advanced LIGO has observed three binary black hole merger events using sensitive interferometers located in Washington state and Louisiana. Based on estimates of the stellar-mass binary black hole merger rate, researchers are confident that additional detections will result from Advanced LIGO’s second run.

[Phys. Rev. X 6, 041015] Published Fri Oct 21, 2016

]]>On atomic scales, some materials can destabilize because of electrostatic forces. Based on experimental evidence, researchers now theorize how exactly atoms rearrange to overcome this destabilization.

[Phys. Rev. X 6, 041011] Published Tue Oct 18, 2016

]]>Information storage can be accomplished using quantum mechanical spin. Now, researchers have demonstrated a ferromagnetic nanostructure that can carry spin-polarized supercurrents.

[Phys. Rev. X 6, 041012] Published Tue Oct 18, 2016

]]>The stochastic thermodynamic properties of an isothermal Brownian engine consisting of a micron-sized colloidal particle are calculated analytically and tested experimentally.

[Phys. Rev. X 6, 041010] Published Mon Oct 17, 2016

]]>A recasting of the theory that underlies thermal transport in electrical insulators relies on new vibrational modes called relaxons.

[Phys. Rev. X 6, 041013] Published Mon Oct 17, 2016

]]>Metasurfaces are engineered systems that enable advanced control of electromagnetic waves over deeply subwavelength thicknesses. Researchers make a careful study of the use of metasurfaces to transform the impinging optical wave front.

[Phys. Rev. X 6, 041008] Published Fri Oct 14, 2016

]]>Short stretches of DNA that can inappropriately bind regulatory proteins are statistically rare in many genomes, suggesting that evolutionary pressure works against them.

[Phys. Rev. X 6, 041009] Published Fri Oct 14, 2016

]]>A stepping stone to experimentally realizing new quantum phases of matter is to determine theoretically which phases are possible as a matter of principle. Researchers have now proposed theories of new topological crystalline insulators in three dimensions.

[Phys. Rev. X 6, 041006] Published Thu Oct 13, 2016

]]>Researchers have added dopant atoms to a quantum spin liquid in an effort to make it superconduct, but the material upended theory by remaining an insulator.

[Phys. Rev. X 6, 041007] Published Thu Oct 13, 2016

]]>Van der Waals interactions are ubiquitous in different materials yet not always described properly by current theories. Now, researchers have determined how to accurately and efficiently treat long-range Van der Waals interactions together with other chemical bonds, new findings that are important for studies of layered materials.

[Phys. Rev. X 6, 041005] Published Wed Oct 12, 2016

]]>Ensembles of ultracold atoms suffer only minimally from thermal fluctuations and, accordingly, are useful in a variety of fields. A new laser-cooling technique is demonstrated that can be applied to simple, abundant atoms such as hydrogen and carbon.

[Phys. Rev. X 6, 041004] Published Mon Oct 10, 2016

]]>Interactions between light and matter are of fundamental interest in a variety of fields, such as solar-energy conversion. A new, accurate method, based on first principles, is used to predict the absorption and emission properties of a range of organic and inorganic molecules.

[Phys. Rev. X 6, 041002] Published Tue Oct 04, 2016

]]>The future of quantum computing hinges on minimizing and correcting computational errors. Researchers investigate errors from the time evolution in systems of exotic quasiparticles, known as anyons, that could provide a well-protected platform for quantum computing.

[Phys. Rev. X 6, 041003] Published Tue Oct 04, 2016

]]>Repeatedly driving a system with electromagnetic pulses can produce dramatically new quantum properties. A theoretical understanding of new types of quantum phases of interacting matter that exist only in the face of periodic driving is presented.

[Phys. Rev. X 6, 041001] Published Mon Oct 03, 2016

]]>Developing more efficient solar cells has long been a goal of scientists, given the current energy crisis. A theoretical study of black phosphorous, a material useful as an infrared photodetector, shows that it can make a more efficient solar cell in the presence of strain.

[Phys. Rev. X 6, 031046] Published Tue Sep 27, 2016

]]>Probing electronic states on ultrafast timescales is critical for studies of chemical reactions. A tabletop method for performing time-resolved x-ray emission spectroscopy is presented and tested using a polypyridyl iron complex.

[Phys. Rev. X 6, 031047] Published Tue Sep 27, 2016

]]>Quantum computers promise to shed light on many areas of research that have proven too computationally expensive even for current supercomputers. Researchers show how a hybrid quantum-classical approach can be used to simulate strongly correlated materials, such as high-temperature superconductors and transition-metal oxides.

[Phys. Rev. X 6, 031045] Published Wed Sep 21, 2016

]]>A compact scheme can directly modulate the phase of a laser without a bulky external modulator.

[Phys. Rev. X 6, 031044] Published Tue Sep 20, 2016

]]>Bosons and fermions, once thought to be distinct entities, can actually be exchanged via the attachment of flux. This observation is used to relate different theories that have applications in fields as diverse as condensed matter physics and string theory.

[Phys. Rev. X 6, 031043] Published Mon Sep 19, 2016

]]>The structural stability of solar-cell absorbing materials is critical to ensure efficient solar cells. Experiments show how a hybrid perovskite material can be degraded by visible light much more easily than conventional semiconductors such as silicon.

[Phys. Rev. X 6, 031042] Published Thu Sep 15, 2016

]]>Multiqubit measurements will play a vital role in quantum information processing. A new experiment constructs complex measurements on three superconducting qubits and develops important tools toward characterizing them.

[Phys. Rev. X 6, 031041] Published Wed Sep 14, 2016

]]>Error correction is a fundamental aspect of quantum codes. Researchers theoretically show that even 5- and 7-qubit codes can yield universal fault-tolerant computation with relatively low overhead.

[Phys. Rev. X 6, 031039] Published Tue Sep 13, 2016

]]>Superconductors carry current without resistance, but excessive current destroys superconductivity. An investigation of this natural “speed limit” gives a better understanding of the properties of copper-oxide-based, high-temperature superconductors.

[Phys. Rev. X 6, 031040] Published Tue Sep 13, 2016

]]>Networks are everywhere: social networks, linked neurons in the brain, and maps of traffic patterns. A long-standing goal has been to divide networks into relevant “communities,” and now researchers demonstrate a better method for doing so.

[Phys. Rev. X 6, 031038] Published Mon Sep 12, 2016

]]>A newly discovered optical vortex forms a ring around many intense laser pulses but was never noticed before.

[Phys. Rev. X 6, 031037] Published Fri Sep 09, 2016

]]>Communication that relies on quantum carriers, like single photons, can achieve a level of privacy unattainable by classical communication methods. In a new experiment, single microwave photons are used as carriers of quantum information in a manner robust to loss.

[Phys. Rev. X 6, 031036] Published Tue Sep 06, 2016

]]>The interfaces between materials are often rich in physical phenomena such as emergent magnetic properties. A new study analyzes the low-temperature properties of the interface between two oxides controlled by cationic defect formation.

[Phys. Rev. X 6, 031035] Published Tue Aug 30, 2016

]]>Quantum metrology shows that it is always possible to estimate the separation of two stars, no matter how close together they are.

[Phys. Rev. X 6, 031033] Published Mon Aug 29, 2016

]]>In high-dimensional data, where the number of measurements can be far smaller than the number of unknown variables, extracting statistical information can be challenging. Scientists theoretically show how classical statistics can be generalized for such “big data.”

[Phys. Rev. X 6, 031034] Published Mon Aug 29, 2016

]]>Bosonic optoelectronic excitations known as polaritons may play crucial roles in futuristic quantum technologies. Researchers investigate the phase coupling between coherent quantum states of polaritons held at roughly 10 degrees above absolute zero.

[Phys. Rev. X 6, 031032] Published Fri Aug 26, 2016

]]>Inducing superconductivity in the surface of a three-dimensional topological insulator has long been a goal of condensed-matter physics. A new experiment realizes this process in a thin film of samarium hexaboride.

[Phys. Rev. X 6, 031031] Published Thu Aug 25, 2016

]]>Superconductivity is a fascinating property in which electrical resistance drops to zero. An investigation into the energy stored in the long-range Coulomb interaction in cuprates furthers understanding of these materials’ high-temperature superconductivity.

[Phys. Rev. X 6, 031027] Published Wed Aug 24, 2016

]]>Light-matter interactions play critical roles in many areas of physics. A new study shows how the paths of electrons liberated from molecules can be effectively measured to extremely high temporal and spatial resolutions.

[Phys. Rev. X 6, 031029] Published Wed Aug 24, 2016

]]>Noise is a fundamental aspect of experimental procedures, and achieving reliable quantum computing requires compensating for errors. Scientists show that certain types of errors can be calibrated out in a 7-qubit quantum error-correcting code in a system of trapped ions.

[Phys. Rev. X 6, 031030] Published Wed Aug 24, 2016

]]>Some of the remarkable behaviors of strongly correlated metals may be controlled by quantum phase transitions. An exact numerical method is used to reveal the properties of a model exhibiting a quantum phase transition between an isotropic and a nematic metal.

[Phys. Rev. X 6, 031028] Published Tue Aug 23, 2016

]]>Quantum information processing of the future may rely on controlling systems of interacting atoms or ions. A theoretical proposal shows how a lattice of ionic crystals can demonstrate critical phases that are neither fully disordered nor fully ordered.

[Phys. Rev. X 6, 031025] Published Mon Aug 22, 2016

]]>Differentiating between Dirac composite fermions and the Halperin-Lee-Read state has long been difficult. Now, a theoretical demonstration shows that the Nernst effect—a type of thermoelectric transport measurement—can be used to test the Dirac nature of composite fermions.

[Phys. Rev. X 6, 031026] Published Mon Aug 22, 2016

]]>A progressive loss of phase information (i.e., decoherence) is fundamental to many physical systems since they evolve over time. Researchers present a way of deriving master equations to dynamically characterize disordered quantum systems with finite dimensions.

[Phys. Rev. X 6, 031023] Published Fri Aug 19, 2016

]]>The central nervous system is a prime example of a complex network. Scientists derive the statistics associated with the interactions between pairs of binary units representing individual neurons.

[Phys. Rev. X 6, 031024] Published Fri Aug 19, 2016

]]>Researchers provide new evidence for the existence of type-II Weyl semimetals, which would be both conducting and insulating in different spatial directions.

[Phys. Rev. X 6, 031021] Published Wed Aug 17, 2016

]]>Observing the effects of quantum phenomena requires relatively long state lifetimes. In a new experiment, ultracold dysprosium atoms are used to demonstrate that spin-orbit coupling persists for 10 to 100 times longer than in other atoms.

[Phys. Rev. X 6, 031022] Published Wed Aug 17, 2016

]]>A Rydberg atom immersed in a dense cloud of ultracold neutral atoms can undergo two chemical processes.

[Phys. Rev. X 6, 031020] Published Wed Aug 10, 2016

]]>Majorana particles are favored in quantum computing, which promises exponential increases in processing speed compared with classical protocols. Now, researchers propose using Majoranas to perform a magic gate that is more resistant to system noise.

[Phys. Rev. X 6, 031019] Published Mon Aug 08, 2016

]]>Pulses of light are made up of quantum particles called photons. A novel way of making individual photons interact could pave the way toward generating photonic “molecules” and even more complex states of light.

[Phys. Rev. X 6, 031017] Published Thu Aug 04, 2016

]]>The field of gravitational-wave astronomy celebrated its first direct detection of a binary black hole merger in 2015. Researchers study what can and cannot be learned through observations of the stochastic background of distant gravitational-wave signals.

[Phys. Rev. X 6, 031018] Published Thu Aug 04, 2016

]]>Preparing, manipulating, and reading out Majorana zero modes is important for quantum computing. A theoretically developed set of milestone experiments, if conducted successfully, may pave the way for fault-tolerant “topological” quantum information processing.

[Phys. Rev. X 6, 031016] Published Wed Aug 03, 2016

]]>Quantum annealing is a quantum enhanced heuristic optimization algorithm that exploits quantum tunneling. New work shows that it can significantly outperform its classical analog (simulated annealing) as well as the most popular classical algorithm for simulating quantum annealing (quantum Monte Carlo).

[Phys. Rev. X 6, 031015] Published Mon Aug 01, 2016

]]>A chiral object cannot be superimposed onto its mirror image—a geometric definition of chirality. A new theoretical study introduces a definition of electromagnetic chirality.

[Phys. Rev. X 6, 031013] Published Thu Jul 28, 2016

]]>Sensing magnetic fields is a key aspect in many areas of study such as biomedical imaging and geophysics. Researchers demonstrate all-optical solid-state magnetometry that is sensitive to magnetic fields weaker than 100 nT.

[Phys. Rev. X 6, 031014] Published Thu Jul 28, 2016

]]>Phase transitions are ubiquitous in nature and can occur in out-of-equilibrium situations. The key role of short-range fluctuations in dissipative phase transitions is theoretically demonstrated and can be experimentally reproduced in the future using trapped ions, Rydberg states of atoms, or microwave circuits.

[Phys. Rev. X 6, 031011] Published Wed Jul 27, 2016

]]>Metals, semiconductors, and insulators all exhibit the spin Seebeck effect, in which a temperature gradient results in current flow. Now, researchers advance our understanding of how the spin Seebeck effect depends on temperature and material properties.

[Phys. Rev. X 6, 031012] Published Wed Jul 27, 2016

]]>It is commonly believed that quantum tunneling is necessary for a quantum speedup in quantum annealing, but a theoretical demonstration shows that quantum tunneling is not always the most efficient way to yield a quantum speedup.

[Phys. Rev. X 6, 031010] Published Thu Jul 21, 2016

]]>Complex networks like neural maps and the internet are characterized by a large number of connected nodes. A new algorithm shows how three-dimensional networks can be computationally simplified by tiling an abstract surface.

[Phys. Rev. X 6, 031009] Published Wed Jul 20, 2016

]]>[Phys. Rev. X 6, 039901] Published Tue Jul 19, 2016

]]>A quantum computer is used to efficiently model a quantum chemical system to extremely high accuracy.

[Phys. Rev. X 6, 031007] Published Mon Jul 18, 2016

]]>Obtaining large quantities of drinkable water via desalinization is often an expensive, complex process. A theoretical method for obtaining clean water from waste is presented, drawing on inspiration from the human kidney.

[Phys. Rev. X 6, 031008] Published Mon Jul 18, 2016

]]>Optimal quantum error-correction codes are necessary to extend the lifetime of quantum memories. A new error-correction code to rectify photon loss, gain, and dephasing errors in electromagnetic cavities is presented.

[Phys. Rev. X 6, 031006] Published Thu Jul 14, 2016

]]>Dynamic networks are common in complex systems, and coarse-graining their evolving structure is a key step to understanding them. General mathematical tools for identifying the theoretical limits of such methods are presented.

[Phys. Rev. X 6, 031005] Published Wed Jul 13, 2016

]]>By bathing a superconducting qubit in squeezed light, researchers have been able to confirm a decades-old prediction for the resulting phase-dependent spectrum of resonance fluorescence.

[Phys. Rev. X 6, 031004] Published Mon Jul 11, 2016

]]>Quasiparticles with no direct analogs in the standard model have been recently revealed in experiments. Researchers theoretically analyze the physical properties of triple point fermions, which can be thought of as a melding of Dirac and Weyl fermions.

[Phys. Rev. X 6, 031003] Published Thu Jul 07, 2016

]]>In quantum circuits, electrical fluctuations render the behavior of the components interdependent, calling for new circuit rules. Now, researchers establish such rules for simple quantum components.

[Phys. Rev. X 6, 031002] Published Tue Jul 05, 2016

]]>Cells that are electrically active and that also produce light for easy voltage monitoring could lead to new studies of heart arrhythmias and possibly bio-computing.

[Phys. Rev. X 6, 031001] Published Fri Jul 01, 2016

]]>A scanning probe detects the quantum states of photons in a microwave circuit, providing the information needed for quantum simulations.

[Phys. Rev. X 6, 021044] Published Thu Jun 30, 2016

]]>Solid-state materials are invariably plagued by disorder in real-world experiments. In a numerical study, researchers investigate the semimetal phases of Dirac and Weyl semimetals characterized by disorder.

[Phys. Rev. X 6, 021042] Published Wed Jun 29, 2016

]]>Hybrid quantum-classical computation may be a hallmark of future technologies. Researchers investigate the tradeoff between employing quantum and classical resources for computational tasks.

[Phys. Rev. X 6, 021043] Published Wed Jun 29, 2016

]]>Entanglement purification, a vital enabler for practical quantum networks, has been shown to be feasible with secluded nuclear memories in diamond.

[Phys. Rev. X 6, 021040] Published Wed Jun 22, 2016

]]>Current liquid-crystal research will pave the way for next-generation electro-optical displays. Researchers experimentally and theoretically characterize the fluctuation modes of a new phase of liquid crystals.

[Phys. Rev. X 6, 021041] Published Wed Jun 22, 2016

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