ALBERT

Description: After many years of delays, the €1.7 billion Facility for Antiproton and Ion Research, an extension of the GSI Helmholtz Center for Heavy Ion Research near Darmstadt, Germany, may finally get built. At a council meeting on 27 and 28 June, the partner countries—eight European Union members plus India and Russia—concluded that they have enough money to cover a €320 million budget gap; they will now seek building permits from the German government. Still, some countries have yet to commit their share of the missing cash, including Russia, which had agreed to bear about 18% of FAIR's total construction cost, the second largest contribution after Germany's 70%. Author: Edwin Cartlidge

Description: Author: Jelena Stajic

Description: Author: Jelena Stajic

Description: Author: Ian S. Osborne

Description: Author: Jelena Stajic

Description: Density functional theory (DFT) stands out from all first-principles quantum mechanical methods for the simulation of materials, as it enables very good approximations for the complicated components of electronic motion called exchange and correlation. DFT is the method of choice for many materials simulations because of the availability of general-purpose programs that can perform calculations on any material. Results obtained with one DFT program need to be reproducible by any of the other DFT programs, and this has not been straightforward up to now. On page 10.1126/science.aad3000 of this issue, Lejaeghere et al. (1) describe an extensive effort by developers of the major solid-state DFT codes to provide a unified and reproducible benchmark of precision for their calculations based on a reliable criterion, the so-called Δ gauge. Using the Δ gauge, the authors found that the level of precision that can be achieved today in DFT calculations of elemental crystalline solids is comparable to the precision of the most advanced techniques for experimental measurement of the properties of materials. The work leads to the conclusion that the DFT simulation of elemental crystalline solids is a (computationally) solved problem, but also poses the question of whether we can achieve the same levels of validation and reproducibility for more complex simulations of materials involving several elements and/or several methods. Author: Chris-Kriton Skylaris

Description: The photoemission of electrons from atoms, molecules, and condensed matter provides the experimental basis of our understanding of electronic structure. During the process of photoemission, a sufficiently large quantum of electromagnetic radiation (a photon) is absorbed by matter and converted into an electronic excitation, promoting a bound electron into a final state above the vacuum energy Evac. In photoemission spectroscopy, the kinetic energy and momentum of electrons in such final states are analyzed after their propagation to a distant detector. To determine the electronic structure of the sample, the “sudden approximation” has to be fulfilled, whereby the photoelectron leaves the sample fast enough, without further interaction with the remaining electronic structure. On page 62 of this issue, Tao et al. (1) provide unprecedented insight into final-state dynamics by measuring the time a photoelectron takes to leave a solid material for characteristically different final states. By comparing an electron excited to a final state of a nickel solid Ψ Nif with one excited to a state of vacuum Ψ vacf, they establish that a photoelectron resides in the final state for 200 attoseconds (as) (2 × 10−16 s) before it leaves the nickel (see the figure). Such time scales would still allow for the electron to interact with its surroundings and, thus, are relevant for the validity of the sudden approximation. Authors: Uwe Bovensiepen, Manuel Ligges

Description: Author: Jelena Stajic

Description: When a multibillion-dollar physics experiment is canceled, it's tempting to look for lessons that can be applied to future megascience projects. A new book on the rise and fall of the Superconducting Supercollider (SSC) by a trio of science historians takes on that challenge. And while the authors do an excellent job of describing what occurred in the decade from its inception to its demise, they stumble when trying to assign blame. Author: Jeffrey Mervis

Description: The anomalous metallic state in the high-temperature superconducting cuprates is masked by superconductivity near a quantum critical point. Applying high magnetic fields to suppress superconductivity has enabled detailed studies of the normal state, yet the direct effect of strong magnetic fields on the metallic state is poorly understood. We report the high-field magnetoresistance of thin-film La 2– x Sr x CuO 4 cuprate in the vicinity of the critical doping, 0.161 ≤ p ≤ 0.190. We find that the metallic state exposed by suppressing superconductivity is characterized by magnetoresistance that is linear in magnetic fields up to 80 tesla. The magnitude of the linear-in-field resistivity mirrors the magnitude and doping evolution of the well-known linear-in-temperature resistivity that has been associated with quantum criticality in high-temperature superconductors.

Description: Quantum phase transitions (QPTs) are ubiquitous in strongly correlated materials. However, the microscopic complexity of these systems impedes the quantitative understanding of QPTs. We observed and thoroughly analyzed the rich strongly correlated physics in two profoundly dissimilar regimes of quantum criticality. With a circuit implementing a quantum simulator for the three-channel Kondo model, we reveal the universal scalings toward different low-temperature fixed points and along the multiple crossovers from quantum criticality. An unanticipated violation of the maximum conductance for ballistic free electrons is uncovered. The present charge pseudospin implementation of a Kondo impurity opens access to a broad variety of strongly correlated phenomena.

Description: Attosecond metrology of atoms has accessed the time scale of the most fundamental processes in quantum mechanics. Transferring the time-resolved photoelectric effect from atoms to molecules considerably increases experimental and theoretical challenges. Here we show that orientation- and energy-resolved measurements characterize the molecular stereo Wigner time delay. This observable provides direct information on the localization of the excited electron wave packet within the molecular potential. Furthermore, we demonstrate that photoelectrons resulting from the dissociative ionization process of the CO molecule are preferentially emitted from the carbon end for dissociative 2 states and from the center and oxygen end for the 2 states of the molecular ion. Supported by comprehensive theoretical calculations, this work constitutes a complete spatially and temporally resolved reconstruction of the molecular photoelectric effect.

Description: The ultrafast laser excitation of matters leads to nonequilibrium states with complex solid-liquid phase-transition dynamics. We used electron diffraction at mega–electron volt energies to visualize the ultrafast melting of gold on the atomic scale length. For energy densities approaching the irreversible melting regime, we first observed heterogeneous melting on time scales of 100 to 1000 picoseconds, transitioning to homogeneous melting that occurs catastrophically within 10 to 20 picoseconds at higher energy densities. We showed evidence for the heterogeneous coexistence of solid and liquid. We determined the ion and electron temperature evolution and found superheated conditions. Our results constrain the electron-ion coupling rate, determine the Debye temperature, and reveal the melting sensitivity to nucleation seeds.

Description: Topology and disorder have a rich combined influence on quantum transport. To probe their interplay, we synthesized one-dimensional chiral symmetric wires with controllable disorder via spectroscopic Hamiltonian engineering, based on the laser-driven coupling of discrete momentum states of ultracold atoms. Measuring the bulk evolution of a topological indicator after a sudden quench, we observed the topological Anderson insulator phase, in which added disorder drives the band structure of a wire from topologically trivial to nontrivial. In addition, we observed the robustness of topologically nontrivial wires to weak disorder and measured the transition to a trivial phase in the presence of strong disorder. Atomic interactions in this quantum simulation platform may enable realizations of strongly interacting topological fluids.

Description: Developing alternative paradigms of electronics beyond silicon technology requires the exploration of fundamentally new physical mechanisms, such as the valley-specific phenomena in hexagonal two-dimensional materials. We realize ballistic valley Hall kink states in bilayer graphene and demonstrate gate-controlled current transmission in a four-kink router device. The operations of a waveguide, a valve, and a tunable electron beam splitter are demonstrated. The valley valve exploits the valley-momentum locking of the kink states and reaches an on/off ratio of 8 at zero magnetic field. A magnetic field enables a full-range tunable coherent beam splitter. These results pave a path to building a scalable, coherent quantum transportation network based on the kink states.

Description: Metamaterials constructed from deep subwavelength building blocks have been used to demonstrate phenomena ranging from negative refractive index and -near-zero to cloaking, emulations of general relativity, and superresolution imaging. More recently, metamaterials have been suggested as a new platform for quantum optics. We present the use of a dielectric metasurface to generate entanglement between the spin and orbital angular momentum of photons. We demonstrate the generation of the four Bell states on a single photon by using the geometric phase that arises from the photonic spin-orbit interaction and subsequently show nonlocal correlations between two photons that interacted with the metasurface. Our results show that metamaterials are suitable for the generation and manipulation of entangled photon states, introducing the area of quantum optics metamaterials.

Description: Metasurfaces based on resonant nanophotonic structures have enabled innovative types of flat-optics devices that often outperform the capabilities of bulk components, yet these advances remain largely unexplored for quantum applications. We show that nonclassical multiphoton interferences can be achieved at the subwavelength scale in all-dielectric metasurfaces. We simultaneously image multiple projections of quantum states with a single metasurface, enabling a robust reconstruction of amplitude, phase, coherence, and entanglement of multiphoton polarization-encoded states. One- and two-photon states are reconstructed through nonlocal photon correlation measurements with polarization-insensitive click detectors positioned after the metasurface, and the scalability to higher photon numbers is established theoretically. Our work illustrates the feasibility of ultrathin quantum metadevices for the manipulation and measurement of multiphoton quantum states, with applications in free-space quantum imaging and communications.

Description: Fast, high-fidelity measurement is a key ingredient for quantum error correction. Conventional approaches to the measurement of superconducting qubits, involving linear amplification of a microwave probe tone followed by heterodyne detection at room temperature, do not scale well to large system sizes. We introduce an approach to measurement based on a microwave photon counter demonstrating raw single-shot measurement fidelity of 92%. Moreover, the intrinsic damping of the photon counter is used to extract the energy released by the measurement process, allowing repeated high-fidelity quantum nondemolition measurements. Our scheme provides access to the classical outcome of projective quantum measurement at the millikelvin stage and could form the basis for a scalable quantum-to-classical interface.

Description: In metals, orbital motions of conduction electrons on the Fermi surface are quantized in magnetic fields, which is manifested by quantum oscillations in electrical resistivity. This Landau quantization is generally absent in insulators. Here, we report a notable exception in an insulator—ytterbium dodecaboride (YbB 12 ). The resistivity of YbB 12 , which is of a much larger magnitude than the resistivity in metals, exhibits distinct quantum oscillations. These unconventional oscillations arise from the insulating bulk, even though the temperature dependence of the oscillation amplitude follows the conventional Fermi liquid theory of metals with a large effective mass. Quantum oscillations in the magnetic torque are also observed, albeit with a lighter effective mass.

Description: Spin waves are collective excitations of magnetic systems. An attractive setting for studying long-lived spin-wave physics is the quantum Hall (QH) ferromagnet, which forms spontaneously in clean two-dimensional electron systems at low temperature and in a perpendicular magnetic field. We used out-of-equilibrium occupation of QH edge channels in graphene to excite and detect spin waves in magnetically ordered QH states. Our experiments provide direct evidence for long-distance spin-wave propagation through different ferromagnetic phases in the N = 0 Landau level, as well as across the insulating canted antiferromagnetic phase. Our results will enable experimental investigation of the fundamental magnetic properties of these exotic two-dimensional electron systems.

Description: Standard superconductors consist of a condensate of paired electrons, called Cooper pairs. The transport behavior of these pairs at junctions can produce exotic effects that are of fundamental and practical interest. When two superconductors are in contact via a normal metal, the pairs must convert to single-particle states to traverse between superconductors. This occurs by the Andreev process, whereby a low-energy electron in the normal metal injects a Cooper pair into the superconductor and generates a hole that reflects back into the metal; coherent, opposite-momentum electron-hole pairs then carry the supercurrent across the metallic junction (1) (see the figure, panel A). In the case of superconductors connected to a quantum Hall state, there are only one-way paths along the junction edges. Here, a new type of Andreev process is predicted to occur, whereby electron and hole states on opposite sample edges carry the supercurrent. This prediction was made more than 20 years ago (2), but clear observation of the effect was frustrated by the difficulty of creating coexisting superconducting and quantum Hall states. On page 966 of this issue, Amet et al. (3) report on the interplay between these two states, finding evidence for the unconventional Andreev process. Their results confirm new physics that appears when two correlated states are connected, and opens the door to a range of novel excitations and exotic devices. Author: Nadya Mason

Description: Grappling with our desire to understand nature, we construct models of the specific systems that we wish to study. Unsurprisingly, such models are generally highly tailored to the system of interest. But are all these models really that distinct? Or, could there be a universal model that can somehow describe the behavior of any system we could think of? On page 1180 of this issue, De las Cuevas and Cubitt (1) venture out to weave ideas from physics and computer science in an attempt to answer this question for all classical spin models. Author: Stephanie Wehner

Description: The recent report of superconductivity in hydrogen sulfide (H2S) by Drozdov et al. (1) at a record high superconducting critical temperature Tc of 203 K and at high pressure (153 GPa) triggered excitement from both a fundamental and technological perspective. On page 1303 of this issue, Troyan et al. (2) confirm the finding by using an elegant and unexpected implementation of the Mössbauer technique at the third-generation synchrotron facility in Grenoble, France. They measured the Meissner effect (3)—the expulsion of magnetic field from the sample—thereby unequivocally confirming the existence of superconductivity. The new superconductor is believed to have a simple chemical formula, H3S. The superconductivity in H3S was predicted theoretically by Duan et al. (4) before the first experimental findings were reported. The technique has great potential for future studies of tiny samples squeezed to extremely high pressure. This experimental advance paves the road to probing superconductivity in metallic hydrogen, which is expected to be a room-temperature superconductor above 500 GPa (5). Author: Viktor Struzhkin

Description: Turn a switch and the light goes on. The layman's perception is that this is like opening a tap so that the water starts running. But this analogy is misleading. The flow of water is governed by the theory of hydrodynamics, whereby the behavior of the fluid does not require knowledge of the motions of individual molecules. Electrical currents in solids, however, are formed from electrons. In metals, these do not collide with each other, but they do scatter from lattice imperfections. The resulting “Knudsen flow” of electrons is reminiscent of the avalanche of balls cascading through a dense forest of pins, as in a Pachinko machine. On pages 1058, 1055, and 1061 of this issue, evidence is presented that electrons can actually yield to the laws of hydrodynamics (1–3). What is additionally surprising is that these observations are in agreement with mathematical techniques borrowed from string theory (4). These techniques have been applied to describe strongly interacting forms of quantum matter, predicting that they should exhibit hydrodynamic flows (5). Author: Jan Zaanen

Description: The 20th-century philosopher Wilfrid Sellars characterized the aim of philosophy as "to understand how things in the broadest possible sense of the term hang together in the broadest possible sense of the term." This is also physicist Sean Carroll's aim in his new book, The Big Picture. He sets out to show how various phenomena, including thought, choice, conscioussness, and value, hang together with the scientific account of reality that has been developed in physics in the past 100 years. He attempts to do all this without relying on specialized jargon from philosophy and physics, and succeeds spectacularly in achieving both aims. Author: Barry Loewer

Description: An inherent aspect of any two-dimensional (2D) sheet is that all atoms in the material lie on the surface. This leads to a concept of 2D crystals as a “canvas,” where different chemical groups or “ink” on the surface can lead to a palette of distinct materials properties. The most well-studied 2D crystal is graphene, a one-atom-thick sheet of carbon atoms arranged in a honeycomb lattice. Although graphene's superlative materials properties and novel physical phenomena have led to a variety of applications (1), better tunability of these properties is still required. Toward this end, hydrogenated graphene (graphane) was predicted to have a wide band gap and exhibit magnetic order (2–4), in contrast to graphene, which is (semi)metallic and diamagnetic. The chemical stability of graphene makes hydrogenation difficult to control, and this has hampered efforts to tune its electronic or magnetic properties. On page 437 of this issue, González-Herrero et al. (5) report direct evidence that hydrogen atoms on graphene do indeed yield a magnetic moment and that these moments can order ferromagnetically over relatively large distances. If these methods can be extended to industrial scales, then one can imagine storing information at unprecedented densities by painting magnetic bits on graphene canvases (see the figure). Authors: S. M. Hollen, J. A. Gupta

Description: Storing information in an ensemble of single-atom magnets represents the ultimate miniaturization of data storage technology, in which two specific orientations of each atomic magnetic moment represent a bit (a 0 or 1) of information (see the figure, panel A). The inherent dilemma in using a single-atom magnet is keeping it magnetized—or, in other words, being able to hold the information in one of the bit states without an external magnetic field for a useful amount of time and at practical temperatures (1, 2). This phenomenon of magnetic remanence is dif cult to realize from a single atom, in part because diminished robustness against fluctuations from the environment can unintentionally flip the magnetic state, thus wiping out the magnetic memory. A recent attempt to observe remanence in a single atom (3) proved premature, as the results were incompatible with the magnetic ground state of that system (4) and could not be reproduced (4, 5). Hence, the question of whether this defining property of a single-atom magnet can actually be achieved has remained an open question until now. On page 318 of this issue, Donati et al. (6) demonstrate that single holmium atoms exhibit magnetic remanence up to temperatures of 40 K, much higher than previous records of atomic-scale magnets composed of 3 to 12 atoms (1, 2, 5)—a record in both size and stability for any magnet. Authors: Alexander Ako Khajetoorians, Andreas J. Heinrich

Description: Taking advantage of nuclear spins for electronic structure analysis, magnetic resonance imaging, and quantum devices hinges on knowledge and control of the surrounding atomic-scale environment. We measured and manipulated the hyperfine interaction of individual iron and titanium atoms placed on a magnesium oxide surface by using spin-polarized scanning tunneling microscopy in combination with single-atom electron spin resonance. Using atom manipulation to move single atoms, we found that the hyperfine interaction strongly depended on the binding configuration of the atom. We could extract atom- and position-dependent information about the electronic ground state, the state mixing with neighboring atoms, and properties of the nuclear spin. Thus, the hyperfine spectrum becomes a powerful probe of the chemical environment of individual atoms and nanostructures.

Description: Ultrafast nonequilibrium dynamics offer a route to study the microscopic interactions that govern macroscopic behavior. In particular, photoinduced phase transitions (PIPTs) in solids provide a test case for how forces, and the resulting atomic motion along a reaction coordinate, originate from a nonequilibrium population of excited electronic states. Using femtosecond photoemission, we obtain access to the transient electronic structure during an ultrafast PIPT in a model system: indium nanowires on a silicon(111) surface. We uncover a detailed reaction pathway, allowing a direct comparison with the dynamics predicted by ab initio simulations. This further reveals the crucial role played by localized photoholes in shaping the potential energy landscape and enables a combined momentum- and real-space description of PIPTs, including the ultrafast formation of chemical bonds.

Description: The search for Majorana bound states (MBSs) has been fueled by the prospect of using their non-Abelian statistics for robust quantum computation. Two-dimensional superconducting topological materials have been predicted to host MBSs as zero-energy modes in vortex cores. By using scanning tunneling spectroscopy on the superconducting Dirac surface state of the iron-based superconductor FeTe 0.55 Se 0.45 , we observed a sharp zero-bias peak inside a vortex core that does not split when moving away from the vortex center. The evolution of the peak under varying magnetic field, temperature, and tunneling barrier is consistent with the tunneling to a nearly pure MBS, separated from nontopological bound states. This observation offers a potential platform for realizing and manipulating MBSs at a relatively high temperature.

Description: Suspended Bernal-stacked graphene multilayers up to an unexpectedly large thickness exhibit a broken-symmetry ground state whose origin remains to be understood. We show that a finite-temperature second-order phase transition occurs in multilayers whose critical temperature ( T c ) increases from 12 kelvins (K) in bilayers to 100 K in heptalayers. A comparison of the data with a phenomenological model inspired by a mean-field approach suggests that the transition is associated with the appearance of a self-consistent valley- and spin-dependent staggered potential that changes sign from one layer to the next, appearing at T c and increasing upon cooling. The systematic evolution with thickness of several measured quantities imposes constraints on any microscopic theory aiming to analyze the nature of electronic correlations in this system.

Description: Synchrotron radiation—namely, electromagnetic radiation produced by charges moving in a curved path—is regularly generated at large-scale facilities where giga–electron volt electrons move along kilometer-long circular paths. We use a metasurface to bend light and demonstrate synchrotron radiation produced by a subpicosecond pulse, which moves along a circular arc of radius 100 micrometers inside a nonlinear crystal. The emitted radiation, in the terahertz frequency range, results from the nonlinear polarization induced by the pulse. The generation of synchrotron radiation from a pulse revolving about a circular trajectory holds promise for the development of on-chip terahertz sources.

Description: The layered semimetal tungsten ditelluride (WTe 2 ) has recently been found to be a two-dimensional topological insulator (2D TI) when thinned down to a single monolayer, with conducting helical edge channels. We found that intrinsic superconductivity can be induced in this monolayer 2D TI by mild electrostatic doping at temperatures below 1 kelvin. The 2D TI–superconductor transition can be driven by applying a small gate voltage. This discovery offers possibilities for gate-controlled devices combining superconductivity and nontrivial topological properties, and could provide a basis for quantum information schemes based on topological protection.

Description: Cuprates exhibit antiferromagnetic, charge density wave (CDW), and high-temperature superconducting ground states that can be tuned by means of doping and external magnetic fields. However, disorder generated by these tuning methods complicates the interpretation of such experiments. Here, we report a high-resolution inelastic x-ray scattering study of the high-temperature superconductor YBa 2 Cu 3 O 6.67 under uniaxial stress, and we show that a three-dimensional long-range-ordered CDW state can be induced through pressure along the a axis, in the absence of magnetic fields. A pronounced softening of an optical phonon mode is associated with the CDW transition. The amplitude of the CDW is suppressed below the superconducting transition temperature, indicating competition with superconductivity. The results provide insights into the normal-state properties of cuprates and illustrate the potential of uniaxial-pressure control of competing orders in quantum materials.

Description: The role of electron-electron interactions in two-dimensional Dirac fermion systems remains enigmatic. Using a combination of nonperturbative numerical and analytical techniques that incorporate both the contact and long-range parts of the Coulomb interaction, we identify the two previously discussed regimes: a Gross-Neveu transition to a strongly correlated Mott insulator and a semimetallic state with a logarithmically diverging Fermi velocity accurately described by the random phase approximation. We predict that experimental realizations of Dirac fermions span this crossover and that this determines whether the Fermi velocity is increased or decreased by interactions. We explain several long-standing mysteries, including why the observed Fermi velocity in graphene is consistently about 20% larger than values obtained from ab initio calculations and why graphene on different substrates shows different behaviors.

Description: Conventional theory predicts that ultrahigh lattice thermal conductivity can only occur in crystals composed of strongly bonded light elements, and that it is limited by anharmonic three-phonon processes. We report experimental evidence that departs from these long-held criteria. We measured a local room-temperature thermal conductivity exceeding 1000 watts per meter-kelvin and an average bulk value reaching 900 watts per meter-kelvin in bulk boron arsenide (BAs) crystals, where boron and arsenic are light and heavy elements, respectively. The high values are consistent with a proposal for phonon-band engineering and can only be explained by higher-order phonon processes. These findings yield insight into the physics of heat conduction in solids and show BAs to be the only known semiconductor with ultrahigh thermal conductivity.

Description: The ability to confine light into tiny spatial dimensions is important for applications such as microscopy, sensing, and nanoscale lasers. Although plasmons offer an appealing avenue to confine light, Landau damping in metals imposes a trade-off between optical field confinement and losses. We show that a graphene-insulator-metal heterostructure can overcome that trade-off, and demonstrate plasmon confinement down to the ultimate limit of the length scale of one atom. This is achieved through far-field excitation of plasmon modes squeezed into an atomically thin hexagonal boron nitride dielectric spacer between graphene and metal rods. A theoretical model that takes into account the nonlocal optical response of both graphene and metal is used to describe the results. These ultraconfined plasmonic modes, addressed with far-field light excitation, enable a route to new regimes of ultrastrong light-matter interactions.

Description: Many-particle entanglement is a fundamental concept of quantum physics that still presents conceptual challenges. Although nonclassical states of atomic ensembles were used to enhance measurement precision in quantum metrology, the notion of entanglement in these systems was debated because the correlations among the indistinguishable atoms were witnessed by collective measurements only. Here, we use high-resolution imaging to directly measure the spin correlations between spatially separated parts of a spin-squeezed Bose-Einstein condensate. We observe entanglement that is strong enough for Einstein-Podolsky-Rosen steering: We can predict measurement outcomes for noncommuting observables in one spatial region on the basis of corresponding measurements in another region with an inferred uncertainty product below the Heisenberg uncertainty bound. This method could be exploited for entanglement-enhanced imaging of electromagnetic field distributions and quantum information tasks.

Description: Modern quantum technologies in the fields of quantum computing, quantum simulation, and quantum metrology require the creation and control of large ensembles of entangled particles. In ultracold ensembles of neutral atoms, nonclassical states have been generated with mutual entanglement among thousands of particles. The entanglement generation relies on the fundamental particle-exchange symmetry in ensembles of identical particles, which lacks the standard notion of entanglement between clearly definable subsystems. Here, we present the generation of entanglement between two spatially separated clouds by splitting an ensemble of ultracold identical particles prepared in a twin Fock state. Because the clouds can be addressed individually, our experiments open a path to exploit the available entangled states of indistinguishable particles for quantum information applications.

Description: Tailored quantum states of light can be created via a transfer of collective quantum states of matter to light modes. Such collective quantum states emerge in interacting many-body systems if thermal fluctuations are overcome by sufficient interaction strengths. Therefore, ultracold temperatures or strong confinement are typically required. We show that the exaggerated interactions between Rydberg atoms allow for collective quantum states even above room temperature. The emerging Rydberg interactions lead both to suppression of multiple Rydberg state excitations and destructive interference due to polariton dephasing. We experimentally implemented a four-wave mixing scheme to demonstrate an on-demand single-photon source. The combination of glass cell technology, identical atoms, and operation around room temperature promises scalability and integrability. This approach has the potential for various applications in quantum information processing and communication.

Description: The robust generation and propagation of multiphoton quantum states are crucial for applications in quantum information, computing, and communications. Although photons are intrinsically well isolated from the thermal environment, scaling to large quantum optical devices is still limited by scattering loss and other errors arising from random fabrication imperfections. The recent discoveries regarding topological phases have introduced avenues to construct quantum systems that are protected against scattering and imperfections. We experimentally demonstrate topological protection of biphoton states, the building block for quantum information systems. We provide clear evidence of the robustness of the spatial features and the propagation constant of biphoton states generated within a nanophotonics lattice with nontrivial topology and propose a concrete path to build robust entangled states for quantum gates.

Description: Photon-mediated interactions between quantum systems are essential for realizing quantum networks and scalable quantum information processing. We demonstrate such interactions between pairs of silicon-vacancy (SiV) color centers coupled to a diamond nanophotonic cavity. When the optical transitions of the two color centers are tuned into resonance, the coupling to the common cavity mode results in a coherent interaction between them, leading to spectrally resolved superradiant and subradiant states. We use the electronic spin degrees of freedom of the SiV centers to control these optically mediated interactions. Such controlled interactions will be crucial in developing cavity-mediated quantum gates between spin qubits and for realizing scalable quantum network nodes.

Description: Graphene is an atomically thin plasmonic medium that supports highly confined plasmon polaritons, or nano-light, with very low loss. Electronic properties of graphene can be drastically altered when it is laid upon another graphene layer, resulting in a moiré superlattice. The relative twist angle between the two layers is a key tuning parameter of the interlayer coupling in thus-obtained twisted bilayer graphene (TBG). We studied the propagation of plasmon polaritons in TBG by infrared nano-imaging. We discovered that the atomic reconstruction occurring at small twist angles transforms the TBG into a natural plasmon photonic crystal for propagating nano-light. This discovery points to a pathway for controlling nano-light by exploiting quantum properties of graphene and other atomically layered van der Waals materials, eliminating the need for arduous top-down nanofabrication.

Description: Single-photon switches and transistors generate strong photon-photon interactions that are essential for quantum circuits and networks. However, the deterministic control of an optical signal with a single photon requires strong interactions with a quantum memory, which has been challenging to achieve in a solid-state platform. We demonstrate a single-photon switch and transistor enabled by a solid-state quantum memory. Our device consists of a semiconductor spin qubit strongly coupled to a nanophotonic cavity. The spin qubit enables a single 63-picosecond gate photon to switch a signal field containing up to an average of 27.7 photons before the internal state of the device resets. Our results show that semiconductor nanophotonic devices can produce strong and controlled photon-photon interactions that could enable high-bandwidth photonic quantum information processing.

Description: Laser-cooled and quantum degenerate atoms are being pursued as quantum simulators and form the basis of today’s most precise sensors. A key challenge toward these goals is to understand and control coherent interactions between the atoms. We observe long-range exchange interactions mediated by an optical cavity, which manifest as tunable spin-spin interactions on the pseudo spin-1/2 system composed of the millihertz linewidth clock transition in strontium. This leads to one-axis twisting dynamics, the emergence of a many-body energy gap, and gap protection of the optical coherence against certain sources of decoherence. Our observations will aid in the future design of versatile quantum simulators and the next generation of atomic clocks that use quantum correlations for enhanced metrology.

Description: The interplay between the oxidation state and the optical properties of molecules is important for applications in displays, sensors, and molecular-based memories. The fundamental mechanisms occurring at the level of a single molecule have been difficult to probe. We used a scanning tunneling microscope (STM) to characterize and control the fluorescence of a single zinc-phthalocyanine radical cation adsorbed on a sodium chloride–covered gold (111) sample. The neutral and oxidized states of the molecule were identified on the basis of their fluorescence spectra, which revealed very different emission energies and vibronic fingerprints. The emission of the charged molecule was controlled by tuning the thickness of the insulator and the plasmons localized at the apex of the STM tip. In addition, subnanometric variations of the tip position were used to investigate the charging and electroluminescence mechanisms.

Description: Active systems can produce a far greater variety of ordered patterns than conventional equilibrium systems. In particular, transitions between disorder and either polar- or nematically ordered phases have been predicted and observed in two-dimensional active systems. However, coexistence between phases of different types of order has not been reported. We demonstrate the emergence of dynamic coexistence of ordered states with fluctuating nematic and polar symmetry in an actomyosin motility assay. Combining experiments with agent-based simulations, we identify sufficiently weak interactions that lack a clear alignment symmetry as a prerequisite for coexistence. Thus, the symmetry of macroscopic order becomes an emergent and dynamic property of the active system. These results provide a pathway by which living systems can express different types of order by using identical building blocks.

Description: 〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Reczek, Colleen R -- Chandel, Navdeep S -- New York, N.Y. -- Science. 2015 Dec 11;350(6266):1317-8. doi: 10.1126/science.aad8671.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Department of Medicine and Robert H. Lurie Cancer Center, Feinberg School of Medicine, Northwestern University, Chicago, IL 60611, USA. ; Department of Medicine and Robert H. Lurie Cancer Center, Feinberg School of Medicine, Northwestern University, Chicago, IL 60611, USA. nav@northwestern.edu.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/26659042" target="_blank"〉PubMed〈/a〉

Description: 〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Bernstein, Rachel -- New York, N.Y. -- Science. 2015 Apr 17;348(6232):269. doi: 10.1126/science.348.6232.269.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/25883332" target="_blank"〉PubMed〈/a〉

Description: Transcriptional regulation and posttranscriptional processing underlie many cellular and organismal phenotypes. We used RNA sequence data generated by Genotype-Tissue Expression (GTEx) project to investigate the patterns of transcriptome variation across individuals and tissues. Tissues exhibit characteristic transcriptional signatures that show stability in postmortem samples. These signatures are dominated by a relatively small number of genes-which is most clearly seen in blood-though few are exclusive to a particular tissue and vary more across tissues than individuals. Genes exhibiting high interindividual expression variation include disease candidates associated with sex, ethnicity, and age. Primary transcription is the major driver of cellular specificity, with splicing playing mostly a complementary role; except for the brain, which exhibits a more divergent splicing program. Variation in splicing, despite its stochasticity, may play in contrast a comparatively greater role in defining individual phenotypes.〈br /〉〈br /〉〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4547472/" target="_blank"〉〈img src="https://static.pubmed.gov/portal/portal3rc.fcgi/4089621/img/3977009" border="0"〉〈/a〉   〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4547472/" target="_blank"〉This paper as free author manuscript - peer-reviewed and accepted for publication〈/a〉〈br /〉〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Mele, Marta -- Ferreira, Pedro G -- Reverter, Ferran -- DeLuca, David S -- Monlong, Jean -- Sammeth, Michael -- Young, Taylor R -- Goldmann, Jakob M -- Pervouchine, Dmitri D -- Sullivan, Timothy J -- Johnson, Rory -- Segre, Ayellet V -- Djebali, Sarah -- Niarchou, Anastasia -- GTEx Consortium -- Wright, Fred A -- Lappalainen, Tuuli -- Calvo, Miquel -- Getz, Gad -- Dermitzakis, Emmanouil T -- Ardlie, Kristin G -- Guigo, Roderic -- HHSN261200800001E/PHS HHS/ -- HHSN268201000029C/HL/NHLBI NIH HHS/ -- HHSN268201000029C/PHS HHS/ -- R01 DA006227-17/DA/NIDA NIH HHS/ -- R01 MH090936/MH/NIMH NIH HHS/ -- R01 MH090941/MH/NIMH NIH HHS/ -- New York, N.Y. -- Science. 2015 May 8;348(6235):660-5. doi: 10.1126/science.aaa0355.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Center for Genomic Regulation (CRG), Barcelona, Catalonia, Spain. Harvard Department of stem cell and regenerative biology, Harvard University, Cambridge, MA, USA. ; Center for Genomic Regulation (CRG), Barcelona, Catalonia, Spain. Department of Genetic Medicine and Development, University of Geneva, Geneva, Switzerland. Institute for Genetics and Genomics in Geneva (iGE3), University of Geneva, Geneva, Switzerland. Swiss Institute of Bioinformatics, Geneva, Switzerland. ; Center for Genomic Regulation (CRG), Barcelona, Catalonia, Spain. Facultat de Biologia, Universitat de Barcelona (UB), Barcelona, Catalonia, Spain. Universitat Pompeu Fabra (UPF), Barcelona, Catalonia, Spain. ; Broad Institute of MIT and Harvard, Cambridge, MA, USA. ; Center for Genomic Regulation (CRG), Barcelona, Catalonia, Spain. Universitat Pompeu Fabra (UPF), Barcelona, Catalonia, Spain. McGill University, Montreal, Canada. ; Center for Genomic Regulation (CRG), Barcelona, Catalonia, Spain. Universitat Pompeu Fabra (UPF), Barcelona, Catalonia, Spain. National Institute for Scientific Computing (LNCC), Petropolis, Rio de Janeiro, Brazil. ; Center for Genomic Regulation (CRG), Barcelona, Catalonia, Spain. Universitat Pompeu Fabra (UPF), Barcelona, Catalonia, Spain. Radboud University, Nijmegen, Netherlands. ; Center for Genomic Regulation (CRG), Barcelona, Catalonia, Spain. Universitat Pompeu Fabra (UPF), Barcelona, Catalonia, Spain. Faculty of Bioengineering and Bioinformatics, Moscow State University, Leninskie Gory 1-73, 119992 Moscow, Russia. ; Center for Genomic Regulation (CRG), Barcelona, Catalonia, Spain. Universitat Pompeu Fabra (UPF), Barcelona, Catalonia, Spain. ; Department of Genetic Medicine and Development, University of Geneva, Geneva, Switzerland. Institute for Genetics and Genomics in Geneva (iGE3), University of Geneva, Geneva, Switzerland. Swiss Institute of Bioinformatics, Geneva, Switzerland. ; Center for Genomic Regulation (CRG), Barcelona, Catalonia, Spain. Harvard Department of stem cell and regenerative biology, Harvard University, Cambridge, MA, USA. Department of Genetic Medicine and Development, University of Geneva, Geneva, Switzerland. Institute for Genetics and Genomics in Geneva (iGE3), University of Geneva, Geneva, Switzerland. Swiss Institute of Bioinformatics, Geneva, Switzerland. Facultat de Biologia, Universitat de Barcelona (UB), Barcelona, Catalonia, Spain. Universitat Pompeu Fabra (UPF), Barcelona, Catalonia, Spain. Broad Institute of MIT and Harvard, Cambridge, MA, USA. McGill University, Montreal, Canada. National Institute for Scientific Computing (LNCC), Petropolis, Rio de Janeiro, Brazil. Radboud University, Nijmegen, Netherlands. Faculty of Bioengineering and Bioinformatics, Moscow State University, Leninskie Gory 1-73, 119992 Moscow, Russia. North Carolina State University, Raleigh, NC, USA. New York Genome Center, New York, NY, USA. Department of Systems Biology, Columbia University, New York, NY, USA. Cancer Center and Department of Pathology, Massachusetts General Hospital, Boston, MA 02114, USA. Institut Hospital del Mar d'Investigacions Mediques (IMIM), Barcelona, Catalonia, Spain. Joint CRG-Barcelona Super Computing Center (BSC)-Institut de Recerca Biomedica (IRB) Program in Computational Biology, Barcelona, Catalonia, Spain. ; North Carolina State University, Raleigh, NC, USA. ; Department of Genetic Medicine and Development, University of Geneva, Geneva, Switzerland. Institute for Genetics and Genomics in Geneva (iGE3), University of Geneva, Geneva, Switzerland. Swiss Institute of Bioinformatics, Geneva, Switzerland. New York Genome Center, New York, NY, USA. Department of Systems Biology, Columbia University, New York, NY, USA. ; Facultat de Biologia, Universitat de Barcelona (UB), Barcelona, Catalonia, Spain. ; Broad Institute of MIT and Harvard, Cambridge, MA, USA. Cancer Center and Department of Pathology, Massachusetts General Hospital, Boston, MA 02114, USA. ; Broad Institute of MIT and Harvard, Cambridge, MA, USA. kardlie@broadinstitute.org roderic.guigo@crg.cat. ; Center for Genomic Regulation (CRG), Barcelona, Catalonia, Spain. Universitat Pompeu Fabra (UPF), Barcelona, Catalonia, Spain. Institut Hospital del Mar d'Investigacions Mediques (IMIM), Barcelona, Catalonia, Spain. Joint CRG-Barcelona Super Computing Center (BSC)-Institut de Recerca Biomedica (IRB) Program in Computational Biology, Barcelona, Catalonia, Spain. kardlie@broadinstitute.org roderic.guigo@crg.cat.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/25954002" target="_blank"〉PubMed〈/a〉

Description: 〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Dantzer, Ben -- New York, N.Y. -- Science. 2015 Feb 20;347(6224):822-3. doi: 10.1126/science.aaa6480.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Department of Psychology and Department of Ecology and Evolutionary Biology, University of Michigan, Ann Arbor, MI 48109, USA. dantzer@umich.edu.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/25700499" target="_blank"〉PubMed〈/a〉

Description: Sex determination in the mosquito Aedes aegypti is governed by a dominant male-determining factor (M factor) located within a Y chromosome-like region called the M locus. Here, we show that an M-locus gene, Nix, functions as an M factor in A. aegypti. Nix exhibits persistent M linkage and early embryonic expression, two characteristics required of an M factor. Nix knockout with clustered regularly interspaced short palindromic repeats (CRISPR)-Cas9 resulted in largely feminized genetic males and the production of female isoforms of two key regulators of sexual differentiation: doublesex and fruitless. Ectopic expression of Nix resulted in genetic females with nearly complete male genitalia. Thus, Nix is both required and sufficient to initiate male development. This study provides a foundation for mosquito control strategies that convert female mosquitoes into harmless males.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Hall, Andrew Brantley -- Basu, Sanjay -- Jiang, Xiaofang -- Qi, Yumin -- Timoshevskiy, Vladimir A -- Biedler, James K -- Sharakhova, Maria V -- Elahi, Rubayet -- Anderson, Michelle A E -- Chen, Xiao-Guang -- Sharakhov, Igor V -- Adelman, Zach N -- Tu, Zhijian -- AI113643/AI/NIAID NIH HHS/ -- New York, N.Y. -- Science. 2015 Jun 12;348(6240):1268-70. doi: 10.1126/science.aaa2850. Epub 2015 May 21.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Interdisciplinary PhD Program in Genetics, Bioinformatics, and Computational Biology, Virginia Polytechnic Institute and State University (Virginia Tech), Blacksburg, VA, USA. Department of Biochemistry, Virginia Tech, Blacksburg, VA, USA. Fralin Life Science Institute, Virginia Tech, Blacksburg, VA, USA. ; Fralin Life Science Institute, Virginia Tech, Blacksburg, VA, USA. Department of Entomology, Virginia Tech, Blacksburg, VA, USA. ; Department of Biochemistry, Virginia Tech, Blacksburg, VA, USA. Fralin Life Science Institute, Virginia Tech, Blacksburg, VA, USA. ; Department of Biochemistry, Virginia Tech, Blacksburg, VA, USA. ; School of Public Health and Tropical Medicine, Southern Medical University, Guangdong, People's Republic of China. ; Interdisciplinary PhD Program in Genetics, Bioinformatics, and Computational Biology, Virginia Polytechnic Institute and State University (Virginia Tech), Blacksburg, VA, USA. Fralin Life Science Institute, Virginia Tech, Blacksburg, VA, USA. Department of Entomology, Virginia Tech, Blacksburg, VA, USA. ; Interdisciplinary PhD Program in Genetics, Bioinformatics, and Computational Biology, Virginia Polytechnic Institute and State University (Virginia Tech), Blacksburg, VA, USA. Fralin Life Science Institute, Virginia Tech, Blacksburg, VA, USA. Department of Entomology, Virginia Tech, Blacksburg, VA, USA. jaketu@vt.edu zachadel@vt.edu. ; Interdisciplinary PhD Program in Genetics, Bioinformatics, and Computational Biology, Virginia Polytechnic Institute and State University (Virginia Tech), Blacksburg, VA, USA. Department of Biochemistry, Virginia Tech, Blacksburg, VA, USA. Fralin Life Science Institute, Virginia Tech, Blacksburg, VA, USA. jaketu@vt.edu zachadel@vt.edu.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/25999371" target="_blank"〉PubMed〈/a〉

Description: During rest, brain activity is synchronized between different regions widely distributed throughout the brain, forming functional networks. However, the molecular mechanisms supporting functional connectivity remain undefined. We show that functional brain networks defined with resting-state functional magnetic resonance imaging can be recapitulated by using measures of correlated gene expression in a post mortem brain tissue data set. The set of 136 genes we identify is significantly enriched for ion channels. Polymorphisms in this set of genes significantly affect resting-state functional connectivity in a large sample of healthy adolescents. Expression levels of these genes are also significantly associated with axonal connectivity in the mouse. The results provide convergent, multimodal evidence that resting-state functional networks correlate with the orchestrated activity of dozens of genes linked to ion channel activity and synaptic function.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Richiardi, Jonas -- Altmann, Andre -- Milazzo, Anna-Clare -- Chang, Catie -- Chakravarty, M Mallar -- Banaschewski, Tobias -- Barker, Gareth J -- Bokde, Arun L W -- Bromberg, Uli -- Buchel, Christian -- Conrod, Patricia -- Fauth-Buhler, Mira -- Flor, Herta -- Frouin, Vincent -- Gallinat, Jurgen -- Garavan, Hugh -- Gowland, Penny -- Heinz, Andreas -- Lemaitre, Herve -- Mann, Karl F -- Martinot, Jean-Luc -- Nees, Frauke -- Paus, Tomas -- Pausova, Zdenka -- Rietschel, Marcella -- Robbins, Trevor W -- Smolka, Michael N -- Spanagel, Rainer -- Strohle, Andreas -- Schumann, Gunter -- Hawrylycz, Mike -- Poline, Jean-Baptiste -- Greicius, Michael D -- IMAGEN consortium -- 93558/Medical Research Council/United Kingdom -- R01 MH085772-01A1/MH/NIMH NIH HHS/ -- R01NS073498/NS/NINDS NIH HHS/ -- U54 EB020403/EB/NIBIB NIH HHS/ -- Department of Health/United Kingdom -- Wellcome Trust/United Kingdom -- New York, N.Y. -- Science. 2015 Jun 12;348(6240):1241-4. doi: 10.1126/science.1255905. Epub 2015 Jun 11.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Functional Imaging in Neuropsychiatric Disorders Laboratory, Department of Neurology and Neurological Sciences, Stanford University, Stanford, CA, USA. Laboratory of Neurology and Imaging of Cognition, Department of Neuroscience, University of Geneva, Geneva, Switzerland. jonas.richiardi@unige.ch greicius@stanford.edu. ; Functional Imaging in Neuropsychiatric Disorders Laboratory, Department of Neurology and Neurological Sciences, Stanford University, Stanford, CA, USA. ; The War Related Illness and Injury Study Center, VA Palo Alto Health Care System, Palo Alto, CA, USA. Functional Imaging in Neuropsychiatric Disorders Laboratory, Department of Neurology and Neurological Sciences, Stanford University, Stanford, CA, USA. ; Advanced MRI Section, Laboratory of Functional and Molecular Imaging, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, MD, USA. ; Cerebral Imaging Centre, Douglas Mental Health University Institute, Montreal, Canada. Departments of Psychiatry and Biomedical Engineering, McGill University, Montreal, Canada. ; Department of Child and Adolescent Psychiatry, Central Institute of Mental Health, Medical Faculty Mannheim, Heidelberg University, Mannheim, Germany. ; Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, UK. ; Institute of Neuroscience, Trinity College Dublin, Dublin, Ireland. ; Universitaetsklinikum Hamburg Eppendorf, Hamburg, Germany. ; Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, UK. Department of Psychiatry, Universite de Montreal, Centre Hospitalier Universitaire (CHU) Ste Justine Hospital, Montreal, Canada. ; Department of Addictive Behaviour and Addiction Medicine, Central Institute of Mental Health, Medical Faculty Mannheim, Heidelberg University, Mannheim, Germany. ; Department of Cognitive and Clinical Neuroscience, Central Institute of Mental Health, Medical Faculty Mannheim, Heidelberg University, Mannheim, Germany. ; Neurospin, Commissariat a l'Energie Atomique et aux Energies Alternatives, Paris, France. ; Department of Psychiatry and Psychotherapy, Campus Charite Mitte, Charite-Universitatsmedizin Berlin, Berlin, Germany. ; Institute of Neuroscience, Trinity College Dublin, Dublin, Ireland. Departments of Psychiatry and Psychology, University of Vermont, Burlington, VT, USA. ; School of Physics and Astronomy, University of Nottingham, Nottingham, UK. ; Institut National de la Sante et de la Recherche Medicale, INSERM Unit 1000 "Neuroimaging and Psychiatry," University Paris Sud, Orsay, France. INSERM Unit 1000 at Maison de Solenn, Assistance Publique Hopitaux de Paris (APHP), Cochin Hospital, University Paris Descartes, Sorbonne Paris Cite, Paris, France. ; Rotman Research Institute, University of Toronto, Toronto, Canada. School of Psychology, University of Nottingham, Nottingham, UK. ; The Hospital for Sick Children, University of Toronto, Toronto, Canada. ; Department of Genetic Epidemiology in Psychiatry, Central Institute of Mental Health, Medical Faculty Mannheim, Heidelberg University, Mannheim, Germany. ; Behavioural and Clinical Neuroscience Institute and Department of Psychology, University of Cambridge, Cambridge, UK. ; Department of Psychiatry and Psychotherapy, and Neuroimaging Center, Technische Universitat Dresden, Dresden, Germany. ; Department of Psychopharmacology, Central Institute of Mental Health, Faculty of Clinical Medicine Mannheim, Mannheim, Germany. ; Institute of Psychiatry, Psychology and Neuroscience, King's College London, London, UK. Medical Research Council (MRC) Social, Genetic and Developmental Psychiatry (SGDP) Centre, London, UK. ; Allen Institute for Brain Science, Seattle, WA, USA. ; Helen Wills Neuroscience Institute, University of California Berkeley, Berkeley, CA, USA. ; Functional Imaging in Neuropsychiatric Disorders Laboratory, Department of Neurology and Neurological Sciences, Stanford University, Stanford, CA, USA. jonas.richiardi@unige.ch greicius@stanford.edu.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/26068849" target="_blank"〉PubMed〈/a〉

Description: PIWI-interacting RNAs (piRNAs) protect the animal germ line by silencing transposons. Primary piRNAs, generated from transcripts of genomic transposon "junkyards" (piRNA clusters), are amplified by the "ping-pong" pathway, yielding secondary piRNAs. We report that secondary piRNAs, bound to the PIWI protein Ago3, can initiate primary piRNA production from cleaved transposon RNAs. The first ~26 nucleotides (nt) of each cleaved RNA becomes a secondary piRNA, but the subsequent ~26 nt become the first in a series of phased primary piRNAs that bind Piwi, allowing piRNAs to spread beyond the site of RNA cleavage. The ping-pong pathway increases only the abundance of piRNAs, whereas production of phased primary piRNAs from cleaved transposon RNAs adds sequence diversity to the piRNA pool, allowing adaptation to changes in transposon sequence.〈br /〉〈br /〉〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4545291/" target="_blank"〉〈img src="https://static.pubmed.gov/portal/portal3rc.fcgi/4089621/img/3977009" border="0"〉〈/a〉   〈a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4545291/" target="_blank"〉This paper as free author manuscript - peer-reviewed and accepted for publication〈/a〉〈br /〉〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Han, Bo W -- Wang, Wei -- Li, Chengjian -- Weng, Zhiping -- Zamore, Phillip D -- GM62862/GM/NIGMS NIH HHS/ -- GM65236/GM/NIGMS NIH HHS/ -- HG007000/HG/NHGRI NIH HHS/ -- R01 GM065236/GM/NIGMS NIH HHS/ -- R37 GM062862/GM/NIGMS NIH HHS/ -- U41 HG007000/HG/NHGRI NIH HHS/ -- Howard Hughes Medical Institute/ -- New York, N.Y. -- Science. 2015 May 15;348(6236):817-21. doi: 10.1126/science.aaa1264.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉RNA Therapeutics Institute, Howard Hughes Medical Institute, University of Massachusetts Medical School, 368 Plantation Street, Worcester, MA 01605, USA. Department of Biochemistry and Molecular Pharmacology, University of Massachusetts Medical School, 368 Plantation Street, Worcester, MA 01605, USA. ; RNA Therapeutics Institute, Howard Hughes Medical Institute, University of Massachusetts Medical School, 368 Plantation Street, Worcester, MA 01605, USA. Department of Biochemistry and Molecular Pharmacology, University of Massachusetts Medical School, 368 Plantation Street, Worcester, MA 01605, USA. Program in Bioinformatics and Integrative Biology, University of Massachusetts Medical School, 368 Plantation Street, Worcester, MA 01605, USA. ; Department of Biochemistry and Molecular Pharmacology, University of Massachusetts Medical School, 368 Plantation Street, Worcester, MA 01605, USA. Program in Bioinformatics and Integrative Biology, University of Massachusetts Medical School, 368 Plantation Street, Worcester, MA 01605, USA. zhiping.weng@umassmed.edu phillip.zamore@umassmed.edu. ; RNA Therapeutics Institute, Howard Hughes Medical Institute, University of Massachusetts Medical School, 368 Plantation Street, Worcester, MA 01605, USA. Department of Biochemistry and Molecular Pharmacology, University of Massachusetts Medical School, 368 Plantation Street, Worcester, MA 01605, USA. zhiping.weng@umassmed.edu phillip.zamore@umassmed.edu.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/25977554" target="_blank"〉PubMed〈/a〉

Description: Human vocal development occurs through two parallel interactive processes that transform infant cries into more mature vocalizations, such as cooing sounds and babbling. First, natural categories of sounds change as the vocal apparatus matures. Second, parental vocal feedback sensitizes infants to certain features of those sounds, and the sounds are modified accordingly. Paradoxically, our closest living ancestors, nonhuman primates, are thought to undergo few or no production-related acoustic changes during development, and any such changes are thought to be impervious to social feedback. Using early and dense sampling, quantitative tracking of acoustic changes, and biomechanical modeling, we showed that vocalizations in infant marmoset monkeys undergo dramatic changes that cannot be solely attributed to simple consequences of growth. Using parental interaction experiments, we found that contingent parental feedback influences the rate of vocal development. These findings overturn decades-old ideas about primate vocalizations and show that marmoset monkeys are a compelling model system for early vocal development in humans.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Takahashi, D Y -- Fenley, A R -- Teramoto, Y -- Narayanan, D Z -- Borjon, J I -- Holmes, P -- Ghazanfar, A A -- New York, N.Y. -- Science. 2015 Aug 14;349(6249):734-8. doi: 10.1126/science.aab1058.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Princeton Neuroscience Institute, Princeton University, Princeton, NJ 08544, USA. Department of Psychology, Princeton University, Princeton, NJ 08544, USA. ; Princeton Neuroscience Institute, Princeton University, Princeton, NJ 08544, USA. ; Princeton Neuroscience Institute, Princeton University, Princeton, NJ 08544, USA. Department of Mechanical and Aerospace Engineering and Program in Applied and Computational Mathematics, Princeton University, Princeton, NJ 08544, USA. ; Princeton Neuroscience Institute, Princeton University, Princeton, NJ 08544, USA. Department of Psychology, Princeton University, Princeton, NJ 08544, USA. Department of Ecology and Evolutionary Biology, Princeton University, Princeton, NJ 08544, USA.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/26273055" target="_blank"〉PubMed〈/a〉

Description: Infection with intestinal helminths results in immunological changes that influence co-infections, and might influence fecundity by inducing immunological states affecting conception and pregnancy. We investigated associations between intestinal helminths and fertility in women, using 9 years of longitudinal data from 986 Bolivian forager-horticulturalists, experiencing natural fertility and 70% helminth prevalence. We found that different species of helminth are associated with contrasting effects on fecundity. Infection with roundworm (Ascaris lumbricoides) is associated with earlier first births and shortened interbirth intervals, whereas infection with hookworm is associated with delayed first pregnancy and extended interbirth intervals. Thus, helminths may have important effects on human fertility that reflect physiological and immunological consequences of infection.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Blackwell, Aaron D -- Tamayo, Marilyne A -- Beheim, Bret -- Trumble, Benjamin C -- Stieglitz, Jonathan -- Hooper, Paul L -- Martin, Melanie -- Kaplan, Hillard -- Gurven, Michael -- P01AG022500/AG/NIA NIH HHS/ -- R01AG024119/AG/NIA NIH HHS/ -- R56AG024119/AG/NIA NIH HHS/ -- New York, N.Y. -- Science. 2015 Nov 20;350(6263):970-2. doi: 10.1126/science.aac7902.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Department of Anthropology, University of California Santa Barbara, CA 93106, USA. Tsimane Health and Life History Project, San Borja, Bolivia. Broom Center for Demography, University of California Santa Barbara, CA 93106, USA. blackwell@anth.ucsb.edu. ; Department of Anthropology, University of Missouri, Columbia, MO 65211, USA. ; Tsimane Health and Life History Project, San Borja, Bolivia. Department of Anthropology, University of New Mexico, Albuquerque, NM 87131, USA. ; Department of Anthropology, University of California Santa Barbara, CA 93106, USA. Tsimane Health and Life History Project, San Borja, Bolivia. Broom Center for Demography, University of California Santa Barbara, CA 93106, USA. Center for Evolutionary Medicine, Arizona State University, Tempe, AZ 85287, USA. School of Human Evolution and Social Change, Arizona State University, Tempe, AZ, USA. ; Tsimane Health and Life History Project, San Borja, Bolivia. Department of Anthropology, University of New Mexico, Albuquerque, NM 87131, USA. Institute for Advanced Study in Toulouse, Toulouse, France. ; Tsimane Health and Life History Project, San Borja, Bolivia. Department of Anthropology, Emory University, Atlanta, GA 30322, USA. ; Department of Anthropology, University of California Santa Barbara, CA 93106, USA. Tsimane Health and Life History Project, San Borja, Bolivia. Broom Center for Demography, University of California Santa Barbara, CA 93106, USA.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/26586763" target="_blank"〉PubMed〈/a〉

Description: 〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉de Montjoye, Yves-Alexandre -- Pentland, Alex Sandy -- New York, N.Y. -- Science. 2015 Apr 10;348(6231):195. doi: 10.1126/science.348.6231.195-a.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Media Lab, Massachusetts Institute of Technology, Cambridge, MA 02139, USA. yvesalexandre@demontjoye.com. ; Media Lab, Massachusetts Institute of Technology, Cambridge, MA 02139, USA.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/25859038" target="_blank"〉PubMed〈/a〉

Description: Large-scale data sets of human behavior have the potential to fundamentally transform the way we fight diseases, design cities, or perform research. Metadata, however, contain sensitive information. Understanding the privacy of these data sets is key to their broad use and, ultimately, their impact. We study 3 months of credit card records for 1.1 million people and show that four spatiotemporal points are enough to uniquely reidentify 90% of individuals. We show that knowing the price of a transaction increases the risk of reidentification by 22%, on average. Finally, we show that even data sets that provide coarse information at any or all of the dimensions provide little anonymity and that women are more reidentifiable than men in credit card metadata.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉de Montjoye, Yves-Alexandre -- Radaelli, Laura -- Singh, Vivek Kumar -- Pentland, Alex Sandy -- New York, N.Y. -- Science. 2015 Jan 30;347(6221):536-9. doi: 10.1126/science.1256297.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Media Lab, Massachusetts Institute of Technology (MIT), 20 Amherst Street, Cambridge, MA 02139, USA. yvesalexandre@demontjoye.com. ; Department of Computer Science, Aarhus University, Aabogade 34, Aarhus, 8200, Denmark. ; Media Lab, Massachusetts Institute of Technology (MIT), 20 Amherst Street, Cambridge, MA 02139, USA. School of Communication and Information, Rutgers University, 4 Huntington Street, New Brunswick, NJ 08901, USA. ; Media Lab, Massachusetts Institute of Technology (MIT), 20 Amherst Street, Cambridge, MA 02139, USA.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/25635097" target="_blank"〉PubMed〈/a〉

Description: 〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Mervis, Jeffrey -- New York, N.Y. -- Science. 2015 Jul 3;349(6243):16. doi: 10.1126/science.349.6243.16.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/26138958" target="_blank"〉PubMed〈/a〉

Description: 〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Zitvogel, Laurence -- Kroemer, Guido -- New York, N.Y. -- Science. 2015 Jul 31;349(6247):476-7. doi: 10.1126/science.aac8475.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Gustave Roussy Cancer Campus, F-94805 Villejuif, France. INSERM U1015, F-94805 Villejuif, France. Universite Paris Sud-XI, Faculte de Medecine, Le Kremlin Bicetre, France. Center of Clinical Investigations in Biotherapies of Cancer (CICBT) 507, F-94805 Villejuif, France. ; Equipe 11 labellisee par la Ligue Nationale contre le Cancer, Centre de Recherche des Cordeliers, INSERM U1138, F-75006 Paris, France. Universite Paris Descartes, Sorbonne Paris Cite, F-75006 Paris, France. Universite Pierre et Marie Curie, F-75006 Paris, France. Pole de Biologie, Hopital Europeen Georges Pompidou, AP-HP, F-75015 Paris. Metabolomics and Cell Biology Platforms, Institut Gustave Roussy, F-94805 Villejuif, France. kroemer@orange.fr.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/26228128" target="_blank"〉PubMed〈/a〉

Description: 〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Bodley, John H -- New York, N.Y. -- Science. 2015 Aug 21;349(6250):798-9. doi: 10.1126/science.349.6250.798-b.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Department of Anthropology, Washington State University College of Arts and Sciences, Pullman, WA 99164-2630, USA. bodleyj@wsu.edu.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/26293944" target="_blank"〉PubMed〈/a〉

Description: 〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉DeMarco, Emily -- New York, N.Y. -- Science. 2015 Aug 7;349(6248):570-1. doi: 10.1126/science.349.6248.570.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/26250661" target="_blank"〉PubMed〈/a〉

Description: Blood gas and tissue pH regulation depend on the ability of the brain to sense CO2 and/or H(+) and alter breathing appropriately, a homeostatic process called central respiratory chemosensitivity. We show that selective expression of the proton-activated receptor GPR4 in chemosensory neurons of the mouse retrotrapezoid nucleus (RTN) is required for CO2-stimulated breathing. Genetic deletion of GPR4 disrupted acidosis-dependent activation of RTN neurons, increased apnea frequency, and blunted ventilatory responses to CO2. Reintroduction of GPR4 into RTN neurons restored CO2-dependent RTN neuronal activation and rescued the ventilatory phenotype. Additional elimination of TASK-2 (K(2P)5), a pH-sensitive K(+) channel expressed in RTN neurons, essentially abolished the ventilatory response to CO2. The data identify GPR4 and TASK-2 as distinct, parallel, and essential central mediators of respiratory chemosensitivity.〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Kumar, Natasha N -- Velic, Ana -- Soliz, Jorge -- Shi, Yingtang -- Li, Keyong -- Wang, Sheng -- Weaver, Janelle L -- Sen, Josh -- Abbott, Stephen B G -- Lazarenko, Roman M -- Ludwig, Marie-Gabrielle -- Perez-Reyes, Edward -- Mohebbi, Nilufar -- Bettoni, Carla -- Gassmann, Max -- Suply, Thomas -- Seuwen, Klaus -- Guyenet, Patrice G -- Wagner, Carsten A -- Bayliss, Douglas A -- HL074011/HL/NHLBI NIH HHS/ -- HL108609/HL/NHLBI NIH HHS/ -- New York, N.Y. -- Science. 2015 Jun 12;348(6240):1255-60. doi: 10.1126/science.aaa0922. Epub 2015 Jun 11.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Department of Pharmacology, University of Virginia, Charlottesville, VA 22908, USA. ; Institute of Physiology, University of Zurich, Zurich, CH-8057, Switzerland. ; Institute of Veterinary Physiology, University of Zurich, Zurich, CH-8057, Switzerland. Centre de Recherche du CHU de Quebec, Departement de Pediatrie, Faculte de Medecine, Universite Laval, Quebec, QC, Canada. ; Department of Pharmacology, University of Virginia, Charlottesville, VA 22908, USA. Department of Physiology, Hebei Medical University, Shijiazhuang, Hebei, 050017, China. ; Department of Pharmacology, University of Virginia, Charlottesville, VA 22908, USA. School of Medical Sciences, University of New South Wales, New South Wales 2052, Australia. Department of Neurology, Harvard Medical School and Beth Israel Deaconess Medical Center, Boston, MA, USA. ; Novartis Institutes for Biomedical Research, Basel, CH-4002, Switzerland. ; Institute of Veterinary Physiology, University of Zurich, Zurich, CH-8057, Switzerland. ; Institute of Physiology, University of Zurich, Zurich, CH-8057, Switzerland. Wagnerca@access.uzh.ch bayliss@virginia.edu. ; Department of Pharmacology, University of Virginia, Charlottesville, VA 22908, USA. Wagnerca@access.uzh.ch bayliss@virginia.edu.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/26068853" target="_blank"〉PubMed〈/a〉

Description: 〈br /〉〈span class="detail_caption"〉Notes: 〈/span〉Robinson, Gene E -- New York, N.Y. -- Science. 2015 Dec 11;350(6266):1310-2. doi: 10.1126/science.aad8071.〈br /〉〈span class="detail_caption"〉Author address: 〈/span〉Carl R. Woese Institute for Genomic Biology, Department of Entomology, Neuroscience Program, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA. generobi@illinois.edu.〈br /〉〈span class="detail_caption"〉Record origin:〈/span〉 〈a href="http://www.ncbi.nlm.nih.gov/pubmed/26659038" target="_blank"〉PubMed〈/a〉