Cross-resonance (CR) gates have emerged as a promising scheme for fault-tolerant quantum computation with fixed-frequency qubits. We experimentally implement an entangling CR gate by using a ...microwave-only control in a tunable coupling superconducting circuit, where the tunable coupler provides extra degrees of freedom to verify optimal conditions for constructing a CR gate. By developing a three-qubit Hamiltonian tomography protocol, we systematically investigate the dependency of gate fidelities on spurious qubit interactions and present the first experimental approach to the evaluation of the perturbation impact arising from spectator qubits. Our results reveal that the spectator qubits lead to reductions in CR gate fidelity dependent on Z Z interactions and particular frequency detunings between spectator and gate qubits. The target spectator demonstrates a more serious impact than the control spectator under a standard echo pulse scheme, whereas the degradation of gate fidelity is observed up to 22.5% as both the spectators are present with a modest ZZ coupling to the computational qubits. Our experiments uncover an optimal CR operation regime, and the method we develop here can readily be applied to improving other kinds of two-qubit gates in large-scale quantum circuits.
To realize fault-tolerant quantum computing, it is necessary to store quantum information in logical qubits with error correction functions, realized by distributing a logical state among multiple ...physical qubits or by encoding it in the Hilbert space of a high-dimensional system. Quantum gate operations between these error-correctable logical qubits, which are essential for implementation of any practical quantum computational task, have not been experimentally demonstrated yet. Here we demonstrate a geometric method for realizing controlled-phase gates between two logical qubits encoded in photonic fields stored in cavities. The gates are realized by dispersively coupling an ancillary superconducting qubit to these cavities and driving it to make a cyclic evolution depending on the joint photonic state of the cavities, which produces a conditional geometric phase. We first realize phase gates for photonic qubits with the logical basis states encoded in two quasiorthogonal coherent states, which have important implications for continuous-variable-based quantum computation. Then we use this geometric method to implement a controlled-phase gate between two binomially encoded logical qubits, which have an error-correctable function.
SFTS virus (SFTSV) is a novel bunyavirus that causes severe fever with thrombocytopenia syndrome (SFTS), an emerging infectious disease that occurred in China in recent years, with an average case ...fatality rate of 10–12%. Intervention in the early clinical stage is the most effective measure to reduce the mortality rate of disease. To elucidate the natural course of and immune mechanisms associated with the pathogenesis of SFTSV, 59 laboratory-confirmed SFTS patients in the acute phase, who were hospitalized between October 2010 and September 2011, were enrolled in this study, and the patients sera were dynamically collected and tested for SFTSV viral RNA load, 34 cytokines or chemokines and other related laboratory parameters. All clinical diagnostic factors in the acute phase of SFTS were evaluated and assessed. The study showed that the severity of the disease in 11 (18.6%) patients was associated with abdominal pain (p 0.007; OR = 21.95; 95% CI, 2.32–208.11) and gingival bleeding (p 0.001; OR = 122.11; 95% CI, 6.41–2328). The IP-10, TNF-α, IL-6, IL-10, granzyme B and HSP70 levels were higher over the 7–8 days in severe cases, accompanied by altered AST, CK and LDH levels. HSP70 (p 0.012; OR = 8.29; 95% CI, 1.58–43.40) was independently correlated with the severity of the early acute phase of SFTSV infection. The severity of SFTS can be predicted based on the presence of symptoms such as abdominal pain and gingival bleeding and on the level of HSP70 in the acute phase of the disease.
We present the results of a comprehensive phase-field study of columnar grain growth competition in bi-crystalline samples in two dimensions (2D) and in three dimensions (3D) for small sample ...thicknesses allowing a single row of dendrites to form. We focus on the selection of grain boundary (GB) orientation during directional solidification in the steady-state dendritic regime, and study its dependence upon the orientation of two competing grains. In 2D, we map the entire orientation range for both grains, performing several simulations for each configuration to account for the stochasticity of GB orientation selection and to assess the average GB behavior. We find that GB orientation selection depends strongly on whether the primary dendrite growth directions have lateral components (i.e. components perpendicular to the axis of the temperature gradient) that point in the same or opposite directions in the two grains. We identify a range of grain orientations in which grain selection follows the classical description of Walton and Chalmers. We also identify conditions that favor unusual overgrowth of favorably-oriented dendrites at a converging GB. We propose a simple analytical description that reproduces the average GB orientation selection from 2D simulations within statistical fluctuations of a few degrees. In 3D, we find a similar GB orientation selection as in 2D when secondary branches grow in planes parallel and perpendicular to the sample walls. Remarkably, quasi-2D behavior is also observed even when those perpendicular sidebranching planes are rotated by a finite azimuthal angle about the primary dendrite growth axis as long as the absolute values of those azimuthal angles are equal in both grains. In contrast, when the absolute values of those azimuthal angles differ markedly, we find that unusual overgrowth events at a converging GB are promoted by a high azimuthal angle in the least-favorably-oriented grain. We also find that diverging GBs can be strongly affected by those azimuthal angles, while converging GBs exhibit a weak dependence on those angles. For diverging GBs, GB orientation is also strongly affected by the relative signs of the lateral components of the primary dendrite growth directions in both grains.
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IntroductionRehabilitation services are supposed to facilitate recovery. However, there is no concrete evidence in Taiwan.ObjectivesThis study examined the patterns of rehabilitation service use and ...the association between the pattern of use and personal recovery.MethodsThirty-two community psychiatric rehabilitation centers in Taiwan agreed to participate in this study. A sample of 592 participants filled out the questionnaires. Eight kinds of rehabilitation services were included: Independent living and self-care training, interpersonal and social skills training, daily life arrangement and community life rehabilitation, physical activities, symptom management training, occupational therapy, sheltered workshops, and vocational training. Recovery was measured by the Stage of Recovery Scale. Cluster analysis was utilized to classify service use patterns among the participants. ANOVA was used to examine the association between the pattern of use and recovery.ResultsThe results revealed five patterns of use: (1) Overall middle level with emphasis on work, (2) independent living plus occupational rehabilitation, (3) independent living plus vocational rehabilitation, (4) overall low-level of use, and (5) overall high-level of use. The differences among the five groups of participants in each kind of rehabilitation service were significant (Eta2=19.2%). The recovery status of overall high users was significantly better than middle-level and low users. The recovery status of low-level users was significantly worse than the other four groups.ConclusionsThe findings imply that greater rehabilitation service use is conducive to recovery. Comprehensive use of various types of service or the combination of independent living and other types seem to facilitate recovery.Disclosure of InterestNone Declared
Universal quantum computation1 is striking for its unprecedented capability in processing information, but its scalability is challenging in practice because of the inevitable environment noise. ...Although quantum error correction (QEC) techniques2–8 have been developed to protect stored quantum information from leading orders of error, the noise-resilient processing of the QEC-protected quantum information is highly demanded but remains elusive9. Here, we demonstrate phase gate operations on a logical qubit encoded in a bosonic oscillator in an error-transparent (ET) manner. Inspired by refs. 10,11, the ET gates are extended to the bosonic code and are able to tolerate errors on the logical qubit during gate operations, regardless of the random occurrence time of the error. With precisely designed gate Hamiltonians through photon-number-resolved a.c. Stark shifts, the ET condition is fulfilled experimentally. We verify that the ET gates outperform the non-ET gates with a substantial improvement of gate fidelity after an occurrence of the single-photon-loss error. Our ET gates in superconducting quantum circuits can be readily extended to multiple encoded qubits and a universal gate set is within reach, holding the potential for reliable quantum information processing.Error-transparent quantum gates that can tolerate certain error during the execution of quantum operations have been demonstrated. Substantial improvement of the gate fidelity sheds lights on large-scale universal quantum computation.
Thermal management through personal heating and cooling is a strategy by which to expand indoor temperature setpoint range for large energy saving. We show that nanoporous polyethylene (nanoPE) is ...transparent to mid-infrared human body radiation but opaque to visible light because of the pore size distribution (50 to 1000 nanometers). We processed the material to develop a textile that promotes effective radiative cooling while still having sufficient air permeability, water-wicking rate, and mechanical strength for wearability. We developed a device to simulate skin temperature that shows temperatures 2.7° and 2.0°C lower when covered with nanoPE cloth and with processed nanoPE cloth, respectively, than when covered with cotton. Our processed nanoPE is an effective and scalable textile for personal thermal management.
FeCoCrNi HEA coatings with 20% mass fraction of WC reinforcing particles were prepared by two different cladding methods, laser cladding (LC) and plasma cladding (PC). The microstructure of HEA ...matrix and WC particles of LC and PC coatings were discussed respectively. For HEA matrix, dendritic morphology was observed in both coatings. For WC particles, a few granular (Cr,W)2C carbides around WC particles in LC coatings, and a large number of crystal and fishbone Fe3W3C carbides around WC particles in PC coatings. Mechanical properties as hardness and wear resistance of the two kinds of coatings were also investigated. The interstitial solution strengthening effect of C element is stronger in PC coating, and the hardness of HEA matrix in LC coatings is twice that of in PC coating, which shows a strong retention force on WC particles. The friction coefficient of LC coating is lower and stable, with the volume wear rate of 0.7 × 10−5 mm−3/N·m, showing high wear resistance. PC coatings have poor wear resistance due to decarbonization and oxidation of WC particles and reduction of retention force of HEA matrix, with the volume wear rate of 8.29 × 10−5 mm−3/N·m. The wear mechanism of both coatings were also discussed.
•HEA/WC composite coatings were prepared by laser cladding (LC) and plasma cladding (PC) respectively.•Complex carbides around WC particles were formed in PC coatings.•The interstitial solution strengthening effect of HEA matrix is stronger in LC coatings.•LC coating is abrasive wear mechanism, showing high wear resistance.•PC coatings have poor wear resistance due to the failure of WC particles and weak retention force of HEA matrix.
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