Three-dimensional structures of the spatiotemporal nonlinear Schrödinger equation with power-law nonlinearity in PT-symmetric potentials

The spatiotemporal nonlinear Schrödinger equation with power-law nonlinearity in PT-symmetric potentials is investigated, and two families of analytical three-dimensional spatiotemporal structure solutions are obtained. The stability of these solutions is tested by the linear stability analysis and the direct numerical simulation. Results indicate that solutions are stable below some thresholds for the imaginary part of PT-symmetric potentials in the self-focusing medium, while they are always unstable for all parameters in the self-defocusing medium. Moreover, some dynamical properties of these solutions are discussed, such as the phase switch, power and transverse power-flow density. The span of phase switch gradually enlarges with the decrease of the competing parameter k in PT-symmetric potentials. The power and power-flow density are all positive, which implies that the power flow and exchange from the gain toward the loss domains in the PT cell.Funded by the National Natural Science Foundation of China (Grant No. 11375007), the Zhejiang Provincial Natural Science Foundation of China (Grant No. LY13F050006)

Predicting nonlinear dynamics of optical solitons in optical fiber via the SCPINN

The strongly-constrained physics-informed neural network (SCPINN) is proposed by adding the information of compound derivative embedded into the soft-constraint of physics-informed neural network(PINN). It is used to predict nonlinear dynamics and the formation process of bright and dark picosecond optical solitons, and femtosecond soliton molecule in the single-mode fiber, and reveal the variation of physical quantities including the energy, amplitude, spectrum and phase of pulses during the soliton transmission. The adaptive weight is introduced to accelerate the convergence of loss function in this new neural network. Compared with the PINN, the accuracy of SCPINN in predicting soliton dynamics is improved by 5-11 times. Therefore, the SCPINN is a forward-looking method to study the modeling and analysis of soliton dynamics in the fiber

Frustrated Altermagnetism and Charge Density Wave in Kagome Superconductor CsCr3Sb5

Using first-principles density-functional calculations, we investigate the electronic structure and magnetism of the kagome superconductor CsCr$_3$Sb$_5$. At the ambient pressure, its ground state is found to be $4\times2$ altermagnetic spin-density-wave (SDW) pattern, with an averaged effective moment of $\sim$1.7$\mu_B$ per chromium atom. The magnetic long range order is coupled to the lattice structure, generating 4$a_0$ structural modulation. However, multiple competing SDW phases are present and energetically very close, suggesting strong magnetic fluctuation and frustration. The electronic states near the Fermi level are dominated by Cr-3d orbitals, and flat band or van Hove singularities are away from the Fermi level. When external pressure is applied, the energy differences between competing orders and the structural modulations are suppressed by external pressure. The magnetic fluctuation remains present and important at high pressure because the non-magnetic phase is unstable up to 30 GPa. In addition, a bonding state between Cr-3d$_{xz}$ and Sb$^{\mathrm{II}}$-p$_z$ quickly acquires dispersion and eventually becomes metallic around 5 GPa, leading to a Lifshitz transition. Our findings strongly support unconventional superconductivity in the CsCr$_3$Sb$_5$ compound above 5 GPa, and suggest crucial role of magnetic fluctuations in the pairing mechanism

消化内科护理风险及管理对策分析

Objective: To explore the common nursing risk in department of gastroenterology and clinical nursing management strategies, in order to provide the basis for nursing in the department of gastroenterology. Methods: Analyze and discuss of the common characteristics of nursing risk in our hospital department of gastroenterology, and summarize the countermeasure and method of correlation of risk management. The implementation of risk management as the observation group and the other as the control group, and clinical nursing effect between the two groups would be compared. Moreover, nursing ability improvement circumstance for the nursing staff was compared before and after the implementation of risk management. Results: The observation group after the risk management of nursing errors, medical disputes and the patients' satisfaction were better than the control group, there is statistical significance (P< 0.05). After the risk management in Department of gastroenterology, nursing work of nursing staff in various digestive operation is proficient, medical record documents writing norms, communication ability, the emergency ability is superior before the implementation of risk management, there is statistical significance (P<0.05). Conclusion: In the nursing management in the Department of gastroenterology, the implementation of risk management is helpful to improve the ability of nursing and the nursing quality, reduce nursing risk in Department of gastroenterology, and improve hospital patient satisfaction.目的  探讨消化内科中常见的护理风险以及临床护理管理对策，为消化内科的安全护理提供依据。方法  对本院消化内科常见的护理风险特点进行分析讨论，总结相关风险管理的对策与方法。将未实施风险管理作为对照组，实施风险管理为观察组，比较两组临床护理效果，并对护理人员实施风险管理前、后护理能力改善情况进行对比研究。结果  观察组实施风险管理后护理差错、医疗纠纷以及患者护理满意度方面均优于对照组，比较差异有显著性（P<0.05），具有统计学意义。实施风险管理后护理人员对消化内科各种护理工作操作熟练程度，病历文书书写规范性，沟通能力，应急能力等方面均优于实施风险管理前，比较差异有显著性（P<0.05），具有统计学意义。结论  在消化内科的护理管理中，实施风险管理有助于提高护理能力和护理质量，降低消化内科的护理风险，提高患者的满意度

Integrating radio-over-fiber communication system and BOTDR sensor system

In this paper, we propose and experimentally demonstrate for the first time, the integration of a radio-over-fiber (RoF) communication system and a Brillouin optical time-domain reflectometry (BOTDR) distributed sensor system using a single optical fiber link. In this proof-of-concept integrated system, the communication system is composed of three modulation formats of quadrature phase-shift keying (QPSK), 16-quadrature amplitude modulation (16-QAM) and 64-QAM, which are modulated onto an orthogonal frequency division multiplexing (OFDM) signal. Whereas, the BOTDR sensor system is used for strain and/or temperature monitoring over the fiber distance with a spatial resolution of 5 m using a 25 km single-mode silica fiber. The error vector magnitude (EVM) is analyzed in three modulation formats in the presence of various BOTDR input pump powers. Using QPSK modulation, optimized 18 dBm sensing and 10 dBm data power, the measured EVM values with and without bandpass filter are 3.5% and 14.5%, respectively. The proposed system demonstrates a low temperature measurement error (±0.49 °C at the end of 25 km) and acceptable EVM values, which were within the 3GPP requirements. The proposed integrated system can be effectively applied for practical applications, which significantly reduces the fiber infrastructure cost by effective usage of a single optical fiber lin

Molecular Mechanisms of Hepatocellular Carcinoma Related to Aflatoxins: An Update

Hepatocellular carcinoma (hepatocarcinoma) is a major type of primary liver cancer and one of the most frequent human malignant neoplasms. Aflatoxins are I-type chemical carcinogen for hepatocarcinoma. Increasing evidence has shown that hepatocarcinoma induced by aflatoxins is the result of interaction between aflatoxins and hereditary factor. Aflatoxins can induce DNA damage including DNA strand break, adducts formation, oxidative DNA damage, and gene mutation and determine which susceptible individuals feature cancer. Inheritance such as alterations may result in the activation of proto-oncogenes and the inactivation of tumor suppressor genes and determine individual susceptibility to cancer. Interaction between aflatoxins and genetic susceptible factors commonly involve in almost all pathologic sequence of hepatocarcinoma: chronic liver injury, cirrhosis, atypical hyperplastic nodules, and hepatocarcinoma of early stages. In this review, we discuss the biogenesis, toxification, and epidemiology of aflatoxins and signal pathways of aflatoxin-induced hepatocarcinoma. We also discuss the roles of some important genes related to cell apoptosis, DNA repair, drug metabolism, and tumor metastasis in hepatocarcinogenesis related to aflatoxins

Ultrafast Electron Injection from Photoexcited Perovskite CsPbI3 QDs into TiO2 Nanoparticles with Injection Efficiency near 99%

Photoexcited electron injection dynamics from CsPbI3 quantum dots (QDs) to wide gap metal oxides are studied by transient absorption spectroscopy. Experimental results show under a low excitation intensity that ∼99% of the photoexcited electrons in CsPbI3 QDs can be injected into TiO2 with a size-dependent rate ranging from 1.30 × 1010 to 2.10 × 1010 s–1, which is also ∼2.5 times faster than that in the case of ZnO. A demonstration QD-sensitized solar cell based on a CsPbI3/TiO2 electrode is fabricated that delivers a power conversion efficiency of 5%

Genetic Single Nucleotide Polymorphisms (GSNPs) in the DNA Repair Genes and Hepatocellular Carcinoma Related to Aflatoxin B1 among Guangxiese Population

Aflatoxin B1 (AFB1) is an important environmental carcinogen for the development of hepatocellular carcinoma (HCC). HCC is a complex disease likely resulting from genetic single nucleotide polymorphisms (GSNPs) of multiple interacting genes and gene-environment interactions. Recent efforts have been made to analyze the associations between risk of this malignancy and GSNPs in genes involved in the repair of DNA damage induced by AFB1. Here, we reviewed the results of published case-control studies that have examined the effects of common alleles of all susceptible DNA repair genes, including XRCC1, XRCC3, XRCC4, XRCC7, XPC, and XPD, on risk of AFB1-related HCC among Guangxi population. Statistically significant differences in genotype frequencies found in case-control comparisons were rs25487, rs80309960, rs861539, rs7003908, rs28383151, rs3734091, rs13181, and rs2228001 polymorphism. The overall effects of these GNSPs were moderate in terms of relative risk, with ORs ranging from 2 to 10. Furthermore, some evidence of the interaction of GSNPs in DNA repair genes and AFB1 exposure modulate risk of this cancer was also found, although the results require confirmation with larger sample size studies