Effects of cross-Kerr coupling on transmission spectrum of double-cavity optomechanical system

We theoretically study the transmission spectrum of the cavity field in a double-cavity optomechanical system with cross-Kerr(CK) effect. The system consists of two tunneling coupling optomechanical cavities with a mechanical resonator as a coupling interface. By doping CK medium into the mechanical resonator, CK couplings between the cavity fields and the mechanical resonator are introduced. We investigate the effects of CK coupling strength on the transmission spectrum of the cavity field, including the transmission rate, nonreciprocity and four-wave mixing(FWM). We find that the transmission spectrum of the probe field can show two obvious transparent windows, which can be widened by increasing the CK coupling strength. For the transmission between the two cavity fields, the perfect nonreciprocity and reciprocity are present and modulated by CK coupling and phase difference between two effective optomechanical couplings. In addition, the effects of the optomechanical and CK couplings on FWM show that the single peak of FWM is split into three symmetrical peaks due to the introduction of the CK effect.

直肠癌患者发生低位前切除综合征的相关危险因素

目的分析230例直肠癌患者术后排便功能变化,探索直肠癌保肛手术后患者发生低位前切除综合征(LARS)的相关危险因素。方法选取2013年1月—2017年12月在山西省人民医院行直肠癌低位前切除手术,术中遵循直肠全系膜切除术原则的患者。按手术时间顺序采用电话、当面随访等方式对研究对象的排便功能进行评估。根据患者LARS严重程度,分为有LARS组(轻度及以上症状)和无LARS组,比较两组患者临床资料的差异,探究发生LARS的危险因素。结果230例患者,有LARS组患者126例(54.8%),无LARS组患者104例(45.2%)。两组患者性别、N分期、肿瘤位置、预防性回肠造瘘及有无吻合口漏比较,经χ^2检验,差异有统计学意义(P<0.05)。多因素Logistic回归分析显示,女性[OR=2.301,95%CI(1.239,4.275)]、低位肿瘤[OR=0.410,95%CI(0.288,0.584)]及吻合口漏[OR=29.289,95%CI(1.045,82.533)]是直肠癌患者术后LARS评分的独立影响因素(P<0.05)。结论直肠癌患者术后LARS发生率高,N分期、预防性回肠造瘘对直肠癌患者术后LARS有影响;而女性、低位肿瘤和吻合口漏是其独立危险因素。

Quantum coherence and correlation dynamics of two-qubit system in spin bath environment

The quantum entanglement,discord,and coherence dynamics of two spins in the model of a spin coupled to a spin bath through an intermediate spin are studied.The effects of the important physical parameters including the coupling strength of two spins,the interaction strength between the intermediate spin and the spin bath,the number of bath spins and the temperature of the system on quantum coherence and correlation dynamics are discussed in different cases.The frozen quantum discord can be observed whereas coherence does not when the initial state is the Bell-diagonal state.At finite temperature,we find that coherence is more robust than quantum discord,which is better than entanglement,in terms of resisting the influence of environment.Therefore,quantum coherence is more tenacious than quantum correlation as an important resource.

Dyson–Maleev theory of an X X Z ferrimagnetic spin chain with single-ion anisotropy

We use the mean-field approximation of Dyson–Maleev representation to study an XXZ Heisenberg ferrimagnetic spin chain with single-ion anisotropy. By solving the self-consistent equations with different anisotropies, λ and D respectively,the energy spectrums, internal energy, static susceptibility and specific heat are calculated. Especially, the quantum phase transition of the magnetization plateau induced by single-ion anisotropy D is obtained in the model of the ferrimagnetic spin chain by using Dyson–Maleev mean-field theory.

Opto-electromechanically induced transparency in a hybrid opto-electromechanical system

We study opto-electromechanically induced transparency in a hybrid opto-electromechanical system made up of an optical cavity tunneling-coupled to an opto-mechanical cavity, which is capacitively coupled to a charged mechanical oscillator by a charged and moveable mechanical cavity mirror as an interface. By studying the effects of the different parameters on the output field, we propose a scheme to modulate the opto-electromechanically induced transparency(OEMIT). Our results show that the OEMIT with the transparency windows from single to double to triple can be modulated by changing the tunneling, opto-mechanical and electrical couplings. In addition, the explanation of the OEMIT with multi-windows is given by the energy level diagram based on quantum interference. Our investigation will provide an optimal platform to manipulate the transmission of optical field via microfabricated opto-electromechanical device.

Reversible waveform conversion between microwave and optical fields in a hybrid opto-electromechanical system

We present a scheme of reversible waveform conversion between microwave and optical fields in the hybrid optoelectromechanical system. As an intermediate interface, nanomechanical resonator optomechanically couples both optomechanical cavities in the optical and microwave frequency domains. We find the double-optomechanically induced transparency and achieve coherent signal waveform bi-directional transfer between microwave and optical fields based on quantum interference. In addition, we give an analytical expression of one-to-one correspondence between the microwave field and the optical output field, which intuitively shows the reversible waveform conversion relationship. In particular,by numerical simulations and approximate expression, we demonstrate the conversion effects of the three waveforms and discuss the bi-directional conversion efficiency and the bandwidth. such a hybrid opto-and electro-mechanical device has significant potential functions for electro-optic modulation and waveform conversion of quantum microwave-optical field in optical communications and further quantum networks.

Multiple induced transparency in a hybrid driven cavity optomechanical device with a two-level system

We present a scheme with the multiple-induced transparency windows in a hybrid optomechanical device.By studying the transmission of a probe field through the hybrid device,we show the successive generations of three transparent windows induced by multiple factors including tunneling,optomechanical and qubit-phonon coupling interactions,and analyze the physical mechanism of the induced transparency based on a simplified energy-level diagram of the system.Moreover,the effects of the transition frequency and decay rate of the two-level system on the multiple-induced transparency windows are discussed.We find that the transparency windows can be modulated by the coupling interaction between the qubit and NMR,the decay of qubit and the power of the control field.Therefore,the transmission of the probe field can be coherently adjusted in the hybrid cavity optomechanical device with a two-level system.

A network pharmacology approach to explore the mechanism of Kangguan decoction in the treatment of coronavirus disease 2019 with preliminary verification

Objective:To explore the mechanism of Kangguan decoction in the treatment of coronavirus disease 2019(COVID-19)and then perform preliminary verification.Methods:The effective compounds and target genes of Kangguan decoction were obtained from Traditional Chinese Medicine Systems Pharmacology Database and Analysis Platform.COVID-19 related target genes were searched in the GeneCards database.The active target genes of Kangguan decoction acting on COVID-19 were identified to perform GO function enrichment and KEGG pathway enrichment analysis.The compound-target network and protein-protein interaction were constructed;Molecular docking simulations of macromolecular protein target receptors and their corresponding compounds were performed.The clinical data of COVID-19 patients were retrieved from their electronic medical records of Nantong Third People's Hospital.Results:We screened out 137 effective compounds and 274 effective target genes of Kangguan decoction from TCMSP.The active target genes of Kangguan decoction were compared with the COVID-19 related target genes,and 63 active target genes for Kangguan decoction acting on COVID-19 were identified.GO function enrichment and KEGG pathway enrichment analysis were performed.The compound-target network and PPI network were constructed and the key compounds and key targets were selected to construct a key compound-target network.Finally,the binding of the target and its corresponding components was verified by molecular docking and two clinical cases with obvious clinical efficacy after Kangguan decoction application were demonstrated.Conclusion:The pharmacological mechanism of Kangguan decoction acting on COVID-19 has been explored,and the active compounds and targets of Kangguan decoction acting on COVID-19 and clinical efficacy for Kangguan decoction treating COVID-19 patients have been preliminarily verified.

The Park-and-Ride Behavior in a Cumulative Prospect Theory-Based Model

As an effective travel demand management means,park-and-ride(P&R)mode is an important part of urban traffic.In a traffic corridor with P&R service,suppose that the travel time on highway is uncertain,a cumulative prospect theory(CPT)-based travel decision-making model is established with two travel modes of driving all the way and(P&R).With this setting,the effect of various factors such as the transit fare rate,the parking fee and the total travel demand on the CPT-based and expected utility theory(EUT)-based equilibrium results are compared.In addition,the sensitivity analysis focus on CPT-related parameters are also performed.The numerical results in our case show that the equilibrium flow on P&R mode is always underestimated in an EUT-based model,especially for a low total travel demand.Also,it is found that reducing the transit fare rate or parking fee for P&R station and raising the parking fee for CBD has the same effect on promoting more commuters transfer to P&R mode,whatever CPT-based or EUT-based model is employed.Furthermore,commuter’s reference dependence characteristic is also observed in a CPT-based model,and it is especially noticeable when the road uncertainty is large.

Construction of potential idiopathic pulmonary fibrosis related microRNA and messenger RNA regulatory network

To the Editor:Idiopathic pulmonary fibrosis(IPF)is a kind of lung disease characterized by chronic and progressive pulmonary fibrosis with unknown etiology,whose pathological manifestation is usual interstitial pneumonia.111 However,the prognosis of IPF was still poor,and the median survival time after diagnosis was about 2 to 3 years Therefore,it seems important to seek and develop an effective therapeutic modality for IPF.Through base pairs of intramolecular complementary sequences of messenger RNA(mRNA),microRNA(miRNA)plays a key role in RNA silencing and post-transcriptional gene expression regulation.

利用^(15)N同位素揭示了盐胁迫下棉花氮素的吸收与生长状况

盐胁迫是限制干旱区棉花生长和氮素吸收的重要因素。然而,随着土壤盐渍化威胁的不断加重,针对未扰动下不同盐碱胁迫对棉花养分吸收的影响尚不清楚。本研究利用^(15)N同位素定量识别不同盐胁迫程度下棉花对N的吸收比例与机制,并通过田间试验设计了4种典型盐渍化土壤。结果表明,低盐渍土棉花根、茎和叶的干物质含量与非盐渍土相比不显著。棉花植株生长在中度盐渍化和重度盐渍土中表现出过早衰老。全氮和硝态氮在棉花中的分布是总^(15)N利用率的最佳解释变量,其中棉花^(15)N回收率在26.1%到47.2%之间,土壤^(15)N回收率在7.7%到14.9%之间。这些发现为干旱区盐渍土资源的进一步开发利用和农田生态系统的可持续发展提供了指导。