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Very low-frequency (VLF) and ultralow-frequency (ULF) electromagnetic waves have the advantage of high penetration and low propagation loss in wireless communication systems and are mainly used for underwater and underground communications, as well as for earthquake and lightning forecasting. At present, VLF and ULF antennas are mostly bulky and require hundreds of antennas and more to be set up, which is costly and inefficient. In this paper, we propose to generate VLF and ULF signals by rotating a multilayer multipair electret thin-film electret driven by an excitation device, which improves the problem of low radiation efficiency of VLF and ULF signals and the large size of conventional low-frequency transmitting antennas. Based on a multilayer, multipair electret film mechanical antenna, a magnetic field propagation model is developed, and the relationship between the magnetic flux density mode and the number of layers of electret films, as well as the relationship between the antenna emission frequency and the motor rotation frequency and the number of pairs of electret films, is analyzed. The selection of a suitable model for practical situations based on conditions such as antenna size and propagation distance is illustrated. The research work is of great importance for guiding the design of mechanical antennas and optimizing antenna structures.

Filter methods realize a projection from a superposed quantum state onto a target state, which can be efficient if two states have sufficient overlap. Here we propose a quantum Gaussian filter (QGF) with the filter operator being a Gaussian function of the system Hamiltonian. A hybrid quantum-classical algorithm feasible on near-term quantum computers is developed, which implements the quantum Gaussian filter as a linear combination of Hamiltonian evolution at various times. Remarkably, the linear combination coefficients are determined classically and can be optimized in the postprocessing procedure. Compared to the existing filter algorithms whose coefficients are given in advance, our method is more flexible in practice under given quantum resources with the help of postprocessing on classical computers. We demonstrate the quantum Gaussian filter algorithm for the quantum Ising model with numeral simulations under noises. We also propose an alternative full quantum approach that implements a QGF with an ancillary continuous-variable mode., Comment: 11 pages, 8 figures; close to the published version; code at https://github.com/Min-Quan/QGF-eigensolver

Higher-dimensional topological phases play a key role in understanding the lower-dimensional topological phases and the related topological responses through a dimensional reduction procedure. In this work, we present a Dirac-type model of four-dimensional (4D) $\mathbb{Z}_2$ topological insulator (TI) protected by $\mathcal{CP}$-symmetry, whose 3D boundary supports an odd number of Dirac cones. A specific perturbation splits each bulk massive Dirac cone into two valleys separated in energy-momentum space with opposite second Chern numbers, in which the 3D boundary modes become a nodal sphere or a Weyl semimetallic phase. By introducing the electromagnetic (EM) and pseudo-EM fields, exotic topological responses of our 4D system are revealed, which are found to be described by the (4+1)D mixed Chern-Simons theories in the low-energy regime. Notably, several topological phase transitions occur from a $\mathcal{CP}$-broken $\mathbb{Z}_2$ TI to a $\mathbb{Z}$ TI when the bulk gap closes by giving rise to exotic double-nodal-line/nodal-hyper-torus gapless phases. Finally, we propose to probe experimentally these topological effects in cold atoms., Some typos have been corrected, and the relevant references have been added

The effect of surface energy on the melting of micro/nanoparticles is studied using the asymptotic method. The asymptotic solution of the dynamic model for micro/nanoparticle melting reveals the dependence of the particle melting temperature on the particle size and the anisotropy of surface energy. Specifically, as the particle radius decreases, the isotropic surface energy reduces the melting temperature and accelerates the interface melting of the particle. Along certain crystal orientations, the anisotropy of surface energy enhances the melting temperature of the micro/nanoparticles, whereas depresses the melting temperature of the micro/nanoparticle along other crystal orientations. The anisotropy of surface energy enhances the melting speed of the micro/nanoparticles along certain crystal orientations, whereas reduces the melting speed of the micro/nanoparticles along other crystal orientations. The result of the asymptotic solution is in good agreement with the experimental data.

Magneto-optical effect is a fundamental but broad concept in magnetic mediums. Here we propose a scheme for its quantum emulation using ultracold atoms. By representing the light-medium interaction in the quantum-emulation manner, the artificial magneto-optical effect emerges under an entirely different mechanism from the conventional picture. The underlying polarization state extracted in the synthetic dimension displays a different response to various experimental setups. Notably, the magneto-optical rotation is related to the bulk topology in synthetic dimensions, and thus provides an unambiguous evidence for the desired topological magneto-optical effect, which has not been developed hitherto in ultracold atoms. This scheme is simple and feasible, and can be realized by current experimental techniques. The implementation of the scheme is able to offer an intriguing platform for exploring topological magneto-optical effects and associated physics., 7 pages, 4 figures

We study non-Hermitian spatial symmetries -- a class of symmetries that have no counterparts in Hermitian systems -- and study how normal and exceptional semimetals can be stabilized by these symmetries. Different from internal ones, spatial symmetries act nonlocally in momentum space and enforce global constraints on both band degeneracies and topological quantities at different locations. In deriving general constraints on band degeneracies and topological invariants, we demonstrate that non-Hermitian spatial symmetries are on an equal footing with, but are essentially different from Hermitian ones. First, we discover the nonlocal Hermitian conjugate pair of exceptional or normal band degeneracies that are enforced by non-Hermitian spatial symmetries. Remarkably, we find that these pairs lead to the symmetry-enforced violation of the Fermion doubling theorem in the long-time limit. Second, with the topological constraints, we unravel that certain exceptional manifold is only compatible with and stabilized by non-Hermitian spatial symmetries but is intrinsically incompatible with Hermitian spatial symmetries. We illustrate these findings using two three-dimensional models of a non-Hermitian Weyl semimetal and an exceptional unconventional Weyl semimetal. Experimental cold-atom realizations of both models are also proposed., Major revision, with new content included. Published version

The prevalence of Toxoplasma gondii infection in free-range chickens in Jilin province, northeastern China was investigated. A total of 1095 serum samples were collected from nine administrative regions from July to October, 2012, and antibodies to T. gondii were examined by an in-house enzyme-linked immunosorbent assay (ELISA) using Toxoplasma lysate antigen (TLA). The detection results were confirmed by Western blot. The overall seroprevalence of T. gondii in free-range chickens was 17.6% (95% confidence interval [CI], 15.4-19.4%), ranging from 13.3% (95% CI, 6.3-20.4%) in Siping to 23.6% (95% CI, 15.7-31.6%) in Liaoyuan. There was no significant difference in T. gondii infection among different regions in Jilin province (P0.05). The widespread presence of T. gondii infection in freerange chickens of Jilin province implies the wide contamination with T. gondii oocysts in the living environment of people, and free-range chickens might be an important source of infection for humans.

老年女性，因“反复阵发性眩晕5 d”就诊于北京京煤集团总医院，耳鼻咽喉科门诊拟完善变位试验以明确良性阵发性位置性眩晕诊断，行Dix-Hallpike试验过程中并发腰椎骨折，后转入骨科手术治疗。鉴于有研究表明中老年女性原发性良性阵发性位置性眩晕和骨质疏松之间存在明显相关性，因此对老年女性患者要慎重选择变位试验及手法复位。.

The purpose of this study was to uncover the regulatory effect of LINC00887 on the progression of nasopharyngeal carcinoma (NPC) and the underlying mechanism.Relative level of LINC00887 in NPC tissues and cells was detected by quantitative real-time polymerase chain reaction (qRT-PCR). Thereafter, the regulatory effect of LINC00887 on proliferative ability in SUNE-1 and HK-1 cells was examined by cell counting kit-8 (CCK-8) and 5-Ethynyl-2'-deoxyuridine (EdU) assay. Through Dual-Luciferase reporter gene assay and RNA-Binding Protein Immunoprecipitation (RIP) assay, the interaction in the regulatory loop LINC00887/miRNA-203b-3p/NUP205 was ascertained. At last, rescue experiments were conducted to clarify the involvement of the regulatory loop LINC00887/miRNA-203b-3p/NUP205 in the progression of NPC.Results showed that LINC00887 was upregulated in NPC tissues and cells, and its overexpression markedly stimulated the proliferative ability in NPC cells. In addition, a potential interaction in the regulatory loop LINC00887/miRNA-203b-3p/NUP205 was discovered, which was responsible for promoting the proliferative ability in NPC.LINC00887 promotes the proliferative ability in NPC via absorbing miRNA-203b-3p to upregulate NUP205.

On the basis of Xu’s interfacial wave theory, the stability of dendritic growth in a convective binary alloy melt with buoyancy effect is studied using the asymptotic method. The resulting asymptotic solution of equations reveals that the stability mechanism of dendritic growth in the binary alloy melt with buoyancy-driven convection is similar to that in a pure melt. Dendritic growth is stable above and unstable below a critical stability number [Formula: see text], which is determined by the quantization condition. In particular, there is a critical morphological number in the binary alloy melt. When the morphological number is less than the critical morphological number, the tip growth velocity increases, the tip curvature radius and oscillation frequency decrease, and the interface becomes thinner and smooth. When the morphological number is larger than the critical morphological number, the tip growth velocity decreases, the tip curvature radius and oscillation frequency increase, and the interface becomes fatter and rough. The result demonstrates that in a microgravity environment, there is a critical initial concentration such that below it thermal diffusion dominates, the tip growth velocity increases, the tip curvature radius and oscillation frequency decrease, and the interface becomes thinner and smooth; above it, solute diffusion dominates, the tip growth velocity decreases, the tip curvature radius and oscillation frequency increase, and the interface becomes fatter and rough.

International audience

The integrated energy system (IES) promotes the integration of renewable energy and improves energy efficiency, but it also brings uncertainty to the system. The uncertainty of the output of renewable energy may lead to imbalance of supply and demand, which brings the risk of cost increase to the economic dispatch. This paper mainly studies IES with energy hub as the research object, and studies the IES modeling and the optimal scheduling problem considering Conditional Value-at-Risk (CVaR). Firstly, the mathematical model of energy hub is established. Next, the network model of power system and natural gas system is established and the energy hub is reasonably connected to them. Then, for analyzing the uncertainty of wind power output, this paper develops scenarios using Latin hypercube sampling method and uses K-medoids clustering algorithm to reduce the scenarios. After defining the risk cost under uncertainty, CVaR is introduced into the objective function of IES optimal dispatch to describe the risk which operating personnel faces. Based on CVaR, the IES scheduling model is established and linearized into a mixed integer linear programming problem to be solved. Finally, numerical case studies verify that the IES scheduling model can reduce the risks with least costs and determine whether the system needs to avoid risks.

Incorporating nonlinearity into quantum machine learning is essential for learning a complicated input-output mapping. We here propose quantum algorithms for nonlinear regression, where nonlinearity is introduced with feature maps when loading classical data into quantum states. Our implementation is based on a hybrid quantum computer, exploiting both discrete and continuous variables, for their capacity to encode novel features and efficiency of processing information. We propose encoding schemes that can realize well-known polynomial and Gaussian kernel ridge regressions, with exponentially speed-up regarding to the number of samples., 6 pages, comments are welcome

a new record of Lyophyllum shimeji was collected during field trip to masson pine at Dazhou (31.35° N, 107.72° E; 1100 m altitude) district in 16th of October 2017. It was identified using morphological and molecular techniques. Complete description was performed for the collected fresh fruiting bodies and isolated pure culture. Radial growth rate of culture was estimated on media1, media 2, media 3, media 4, media 5 and media 6 (0.196, 0.192, 0.122, 0.092, 0.200, 0.160 cm/day, respectively). Lyophyllum are very close in morphological characters; hence, the identification was confirmed by DNA sequence analysis of the ribosomal 5.8S rRNA gene including the flanking internal transcribed spacers (ITS). The results showed that it was Lyophyllum shimeji and this is the first record in other parts of China. The suitable culture medium component was potato 200g, MgSO4-7H2O 0.5g, glucose 20 g, KHM2PO4 0.3 g, tryptone 0.5 g, VB1 20 mg, ager 20 g, ddH2O 1000ml, PH5-6. These results could provide a new reference for its artificial domestication and cultivation studies.

In this paper, streamer and breakdown phenomena and their mechanisms of an inhibited Gas-To-Liquid (GTL) transformer oil under standard negative lightning impulse voltages were studied. A conventional inhibited mineral oil was also tested as the benchmark. Experiments were carried out in 25 mm and 50 mm point-plane gaps. Streamer and breakdown phenomena of both oils were observed from the streamer inception voltage level up to the voltage level at which fast streamer appears with velocity over 10 km/s. The results showed that the GTL oil has a higher breakdown voltage and a higher acceleration voltage compared to the mineral oil. This is due to the fact that the GTL oil has a much lower aromatic content compared to the mineral oil. The streamer investigations showed that the development of fast streamers in both oils is the consequence of transition from dark streamer channels to bright streamer channels. By comparing with the results obtained under positive polarity [1], the differences in the propagation mechanisms between the fast negative streamers and fast positive streamers were explained.

Starting from a two-orbital model and based on the random phase approximation, spin excitations in the superconducting state of the newly discovered BiS$_2$ superconductors with three possible pairing symmetries are studied theoretically. We show that spin response is uniquely determined by the pairing symmetry. Possible spin resonance excitations might occur for the d-wave symmetry at an incommensurate momentum about $(0.7\pi,0.7\pi)$. For the p-wave symmetry the transverse spin excitation near $(0,0)$ is enhanced. For the s-wave pairing symmetry there is no spin resonance signature. These distinct features may be used for probing or determining the pairing symmetry in this newly discovered compound., Comment: 4 pages, 5 figures

To analyze the role of oxycodone in acute lung injury(ALI) induced by lipopolysaccharide (LPS) in rats.Male SD rats were randomly allocated into 4 groups: control group, oxycodone group, LPS group, LPS+ oxycodone group. The effects of oxycodone on LPS-induced neutrophils influx, inflammatory cytokines release, pulmonary edema, apoptotic cell were examined. In addition, the toll-like receptor 4 (TLR4) in lung tissues was detected by Western blotting.Oxycodone significantly attenuated LPS-induced pulmonary histopathologic changes, alveolar hemorrhage, and neutrophil infiltration. The lung wet-to-dry weight ratio, was markedly decreased by oxycodone(5.60±0.24 vs 6.80±0.27, P0.05 ). Moreover, oxycodone decreased the productions of the inflammatory cytokines including IL-1β, TNF-α, HMGB-1((1 208±18)pg/ml, (1 660±14) pg/ml, (61±4) pg/ml , all P0.05). Oxycodone treatment also reduced the concentration of apoptosis in lung tissues(18.6%±0.5%, P0.05). Furthermore, the expression of TLR4 was significantly suppressed by oxycodone treatment in lung tissues(1.20±0.15, P0.05).Oxycodone exerts protective effects on LPS-induced ALI in rats. The potential mechanism of this action may attribute partly to the inhibition of TLR4 activation.

As PT and CP symmetries are fundamental in physics, we establish a unified topological theory of PT and CP invariant metals and nodal superconductors, based on the mathematically rigorous KO theory. Representative models are constructed for all nontrivial topological cases in dimensions d=1, 2, and 3, with their exotic physical meanings being elucidated in detail. Intriguingly, it is found that the topological charges of Fermi surfaces in the bulk determine an exotic direction-dependent distribution of topological subgap modes on the boundaries. Furthermore, by constructing an exact bulk-boundary correspondence, we show that the topological Fermi points of the PT and CP invariant classes can appear as gapless modes on the boundary of topological insulators with a certain type of anisotropic crystalline symmetry.

To compare the clinical effects among three kinds of treatments (external fixation, plate fixation, and non-operation) of 1/3 displaced midshaft clavicular fractures in adults.Retrospective analysis was conducted on 306 patients with clavicular fractures in Trauma Orthopedic Department in Jishuitan Hospital from March 2010 to May 2013, and 89 of these patients met the inclusive criteria.Among them, there were 29 cases of external fixation (Group A), 30 cases of plate fixation (Group B), and 30 cases of non-operation with the clavicle sling in Outpatient and Emergency Department (Group C). The average follow-up period was 32 months.The results were evaluated from four perspectives, respectively, follow-up period, Constant Shoulder Score (CSS), Disability of the Arm Shoulder and Hand Score (DASH), and imaging.There was no significant difference in demography, severity of injuries, mechanism of injury, and fracture type among the patients in the three groups.Among 29 cases of external fixation, 25 cases were successfully followed up, 4 were lost.60 cases of plate fixationand non-operation were all successfully followed up.Based on the pairwise comparison of CSS and DASH among the three groups, there was no significant difference between external fixation [(94.0±6.4), (15.2±3.4)Score] and plate fixation[(92.9±8.4), (15.7±3.5)Score] (both P0.05). Mean values of CSS and DASH of non-operation group [(86.0±3.6), (18.0±3.6)Score] were lower than those of the former two groups (P0.001). The healing time of 3 kinds of treatments were as follows: external fixation 10.4±2.32 weeks; plate fixation 12.1±2.5 weeks; and non-operation 15.7±2.2 weeks.In terms of their complications, for the external fixation group, there was 1 case of nonunion (4%); and 3 cases of angulation deformity in the 12(th) week, whose external fixations were maintained till their unions in the 16(th) week.Shortening and displacement did not appear in any cases.In the plate fixation group, there was 1 case of nonunion (3%) and no malunion in this group.The biggest complications of plate fixation were implants stimulus and to remove the plate in the second operation, accounting for 60%.In the non-operation group, there were 3 cases of nonunion (10%), and 12 cases of malunion (40%) including 10 cases without symptoms and 2 cases with symptoms.The satisfaction rates for the appearance of shoulder after these 3 kinds of treatments among the patients were 96%, 93% and 77%, respectively.(1) In treating 1/3 displaced midshaft clavicular fractures in adults, external fixation and plate fixation are overall better than non-operation.And there is no significant difference in curative effects between the two. (2) Both external fixation and plate fixation have its advantages and disadvantages.The choice of treatment must be based on the clinical type of the fracture and the communication with patients.