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Quantum networks of entangled end nodes serve stronger than the classical correlation for unparalleled quantum internet applications. However, practical quantum networking exists noise, at worst, causing end nodes to be described in pre-existing classical data. In such untrusted networks, determining the quantum network fidelity and genuine multi-node entanglement becomes crucial problems. Here, we theoretically and experimentally show that when the network nodes aim to be entangled in a star topology, detecting truly $N$-node Einstein-Podolsky-Rosen steering in networks with high noise tolerance requires only $N+1$ measurement settings. With this small experimental effort, steering detection determines the quantum network fidelity and genuine multi-node entanglement in the presence of untrusted measurement devices. Experimentally, using spontaneous parametric down-conversion entanglement sources, we demonstrate the determinations of genuine 3-photon and 4-photon quantum networks via genuine multi-photon steering and the false positives of the widely used entanglement witnesses. Our results help accurately evaluate setting up realistic entanglement-backbone quantum networks.

Ultra Reliable and Low Latency Communications (URLLC) play a key role in 5G vertical markets, but pose many technical challenges especially when sharing the spectrum with Enhanced Mobile Broadband (eMBB) customers. This study aims to overcome the spectrum inefficiency issue of fully separate (FS) approach and the contention issue of the fully overlap (FO) approach. We present a user-initiated probability elastic resource (UPER) approach by dynamically adjusting the probability of using the shared spectrum for eMBB and URLLC traffic based on the current success and failure status of packet transmission status. The probabilities of successful transmission are derived for UPER, FS, and FO and partially overlap (PO) sharing spectrum approaches. We find that the successful transmission probability of UPER approach is 28% and 46% higher than FS and FO approaches, respectively. We further evaluate the reliability and throughput performance of URLLC and eMBB. When the URLLC packet load is low, the UPER method can almost achieve the best performance of the FS method. When the URLLC packet load is high, we show that UPER can improve the reliability performance up to 54% compared with other methods.

We investigated factors associated with postoperative lipiduria and hypoxemia in patients undergoing surgery for orthopedic fractures. We enrolled patients who presented to our emergency department due to traumatic fractures between 2016 and 2017. We collected urine samples within 24 h after the patients had undergone surgery to determine the presence of lipiduria. Hypoxemia was defined as an SpO2 p = 0.018) and operation time (odd ratio 1.005, 95% CI, 1.000–1.009, p = 0.029) were independently associated with postoperative lipiduria, while age (odd ratio 1.034, 95% CI, 1.003–1.066, p = 0.029), body mass index (odd ratio 1.100, 95% CI, 1.007–1.203, p = 0.035), and operation time (odd ratio 1.005, 95% CI, 1.000–1.010, p = 0.033) were independently associated with postoperative hypoxemia. We identified several factors independently associated with postoperative lipiduria and hypoxemia in patients with fracture undergoing surgical intervention. Operation time was associated with both postoperative lipiduria and hypoxemia, and we recommend that patients with prolonged operation for fractures should be carefully monitored for clinical signs related to fat embolism syndrome.

In recent years, nano-structures used as light harvesting have been widely used in perovskite cells to enhance the photon absorption of cells. The introduction of trapping structures in perovskite cells can change the photon propagation in the cell and the photon energy absorbed by the cell. The nano-structure used in different interfaces of perovskite cells can increase the absorption of light by the device to different degrees, and ultimately improve the efficiency of the solar cell. Therefore, the effective light trapping structure has become trending in the application of perovskite cells. How to effectively apply the such nano-structure is the key to improve the power conversion efficiency(PCE) of perovskite cells. So far, there is three ways including surface antireflection nanostructure, texture structure and plasmon nanostructure to apply to perovskite solar cell. The first one is ordered and disordered antireflection nanostructure that enhance the absorption of light on the surface of perovskite cells and makes visible light scatter at the interface of the nanostructure to reflection probability, the second one is texture structure that can not only improve the light absorption but avoid the formation of short-circuit channel inside the cell, the third one is plasmon nanostructure that can further improve the absorption of the thin film absorption material in the long band, so as to achieve the effect of improving the light utilization and cell efficiency. The trap structure is expected to achieve good photon absorption performance in wide spectral range and wide incidence angle range under the condition of reducing the thickness of active layer. At the same time, it has the advantages of good repeatability, easy to simulate and easy to change the structure. Therefore, using various trap technologies to design efficient trap structure has become a research hotspot in the field of solar cells. So far, most of the reports on the trapping structure have been applied to the silicon-based thin film solar cells, but few of them have been reported on the perovskite cells. This paper starts from the description of the perovskite cell with different nano-structures, comparing and summarizing the different structures, and analyzes the advantages and Disadvantage.

To analyze the clinical characteristics of paroxysmal laryngospasm in adult.A retrospective analysis was performed on 149 patients with paroxysmal laryngospasm in adult. All patients underwent the strobolaryngoscopy, completed the reflux symptom index (RSI) or the reflux finding score (RFS). Partial patients underwent an ambulatory 24-hour pH measurement.Laryngospasm was diagnosed in 76 females and 73 males. The average age was 55.4±11.4. The episode time of 149 (98%) patients last from several seconds tominutes, and 139 (93.3%) episodes could have a spontaneous remission. 84 (56.4%) episodes occurred only in the daytime, 28 (18.8%) only in the nighttime. There were 45.6% over weight/obesity patients, including 40 males and 28 females. The smokers were 28.9% (43/149) including 40 males and 3 females, and the drinkers were 29.5% (44/149) with 39 males and 5 females. 76 (51.0%) patients had no induced factor, while some caused by irritable cough/bucking (53,35.6%), cold (15, 10.1%), excitant food/smell (10, 6.7%), or regurgitation (6.5, 4.0%). Strobolaryngoscopy revealed laryngopharyngeal lesions in 46.3% (69/149) patients, including the glottic lesions with 40 (26.8%), unilateral vocal fold paralysis (21, 14.1%) and supraglottic lesions (8,5.4%). RSI/RFS showed 74.5% (111/149) patients had laryngopharyngeal reflux. Two patients treated with dietary and lifestyle modifications get improved, and 15/16 of the patients responded to antireflux treatment.Episode of paroxysmal laryngospasm occurs more in the daytime, and could have a spontaneous resolution. Paroxysmal laryngospasm is much easier to occur in the male who are overweight or obesity, or with a long-term history of smoking or drinking. Almost half of the patients have an induced factor; partial may have laryngopharyngeal lesions simultaneously. Paroxysmal laryngopharyngeal reflux may be closely related to laryngospasm.

This paper proposes a resource reservation scheme to reduce random access delay for Ultra-Reliable and Low-Latency Communication (URLLC) traffic. URLLC has been proposed as one of the key usage scenarios in the fifth generation (5G) of mobile networks. The primary requirement for providing URLLC services is the delay in the control plane being shorter than 10 ms. Clearly, it is challenging to achieve such the stringent delay requirement since the bursty URLLC requests can cause network congestion in the random access phase. To reduce the random access delay, we propose to reserve random access resources for URLLC during the initial random access transmission. The design criteria of random access and an analytical model for different reservation policies are presented in this paper. Simulation results show that the existing random access scheme fails to meet the delay requirement for URLLC traffic, but our proposed reservation scheme can meet the 10 ms delay requirement with 95% confidence.

Using the adiabatic approximation and adiabatic variational approximation with an effective potential, the total energies and the equilibrium internuclear separations of H2+ ion in states σg, πu, δg, u, γg, ηu in strong magnetic fields have been calculated. Our results reproduced those obtained by Vincke and Baye (Vincke M and Baye D 1985 J. Phys. B: At. Mol. Phys. 18 167), which are considered the most reliable. We found a basic function with better convergence than the Landau functions.

A numerical approach is proposed to simulate the interaction between flow and fishing net in steady current. The numerical approach is based on the joint use of the porous media model and the lumped-mass model. The configuration of flexible net can be simulated using the lumped-mass model and the flow field around plane nets can be simulated using the porous media model. Using an appropriate iterative scheme, the fluid-structure coupling problem can be solved and the steady flow field around flexible net is available. In order to validate the numerical approach, the numerical results are compared with the data obtained from the physical model tests. The comparisons show that both the configuration of the flexible nets and flow velocity results are in accordance with that of the corresponding physical model tests.

In this article,by using the adiabatic approximation and variational principle and introducing an effective potential we have computed some energy levels of hydrogen atom in the presence of a strong magnetic field(1≤β≤2000) and compared our results with the like multi-configuration Hartree-Fock method.We found a basic function with better convergence than the Landau function.

Semi-analytical methods are presented for computing quantum form factors in the general non-hydrogenic case. For transitions between hydrogenic states, semiclassical and quantum form factors are compared in a large domain of momentum transfer. The free electron model is applied to the l-changing Rydberg-atom plus rare-gas collisions between nearly degenerate states on the one hand, and to inelastic n-changing Rydberg-atom plus rare-gas collisions on the other hand. It is shown that the free electron model can be justified in the first case for high values of n(>or=15) and that it breaks down in the second case when large momentum transfers are involved.