Vacuum induced transparency and photon number resolved Autler-Townes splitting in a three-level system

We study the absorption spectrum of a probe field by a {\Lambda}-type three-level system, which is coupled to a quantized control field through the two upper energy levels. The probe field is applied to the ground and the second excited states. When the quantized control field is in vacuum, we derive a threshold condition to discern vacuum induced transparency (VIT) and vacuum induced Autler- Townes splitting (ATS). We also find that the parameter change from VIT to vacuum induced ATS is very similar to that from broken PT symmetry to PT symmetry. Moreover, we find the photon number resolved spectrum in the parameter regime of vacuum induced ATS when the mean photon number of the quantized control field is changed from zero (vacuum) to a finite number. However, there is no photon number resolved spectrum in the parameter regime of VIT even that the quantized control field contains the finite number of photons. Finally, we further discuss possible experimental realization

Study of synchronization for a rotor-pendulum system with Poincare method

A simplified model of the system of unbalanced rotors coupled with pendulum rod is examined. The model consists of two counter-rotating rotors, a rigid pendulum rod and a rigid vibrating body, which is horizontally connected to a fixed support by means of springs. The synchronous state of the system, i.e. synphase and antiphase synchronization of the rotors, is studied by means of the Poincare method. Moreover, the assessment of the synchronous state is converted to find a solution that should satisfy a balanced function and a stability function of the system. However, frequency ratios and installation angular are included in the two functions. It is demonstrated that the spring stiffness and the installation angular have a large influence on the existence and stability of the synchronization state in the coupling system. Finally, computer simulations are preformed to verify the theoretical computations

Energy stable and maximum bound principle preserving schemes for the Q-tensor flow of liquid crystals

In this paper, we propose two efficient fully-discrete schemes for Q-tensor flow of liquid crystals by using the first- and second-order stabilized exponential scalar auxiliary variable (sESAV) approach in time and the finite difference method for spatial discretization. The modified discrete energy dissipation laws are unconditionally satisfied for both two constructed schemes. A particular feature is that, for two-dimensional (2D) and a kind of three-dimensional (3D) Q-tensor flows, the unconditional maximum-bound-principle (MBP) preservation of the constructed first-order scheme is successfully established, and the proposed second-order scheme preserves the discrete MBP property with a mild restriction on the time-step sizes. Furthermore, we rigorously derive the corresponding error estimates for the fully-discrete second-order schemes by using the built-in stability results. Finally, various numerical examples validating the theoretical results, such as the orientation of liquid crystal in 2D and 3D, are presented for the constructed schemes

Quantification of atherosclerotic plaque volume in coronary arteries by computed tomographic angiography in subjects with and without diabetes.

BackgroundDiabetes mellitus (DM) is considered a cardiovascular risk factor. The aim of this study was to analyze the prevalence and volume of coronary artery plaque in patients with diabetes mellitus (DM) vs. those without DM.MethodsThis study recruited consecutive patients who underwent coronary computed tomography (CT) angiography (CCTA) between October 2016 and November 2017. Personal information including conventional cardiovascular risk factors was collected. Plaque phenotypes were automatically calculated for volume of different component. The volume of different plaque was compared between DM patients and those without DM.ResultsAmong 6381 patients, 931 (14.59%) were diagnosed with DM. The prevalence of plaque in DM subjects was higher compared with nondiabetic group significantly (48.34% vs. 33.01%, χ = 81.84, P < 0.001). DM was a significant risk factor for the prevalence of plaque in a multivariate model (odds ratio [OR] = 1.465, 95% CI: 1.258-1.706, P < 0.001). The volume of total plaque and any plaque subtypes in the DM subjects was greater than those in nondiabetic patients significantly (P < 0.001).ConclusionThe coronary artery atherosclerotic plaques were significantly higher in diabetic patients than those in non-diabetic patients

[1,2-Bis(pyridin-2-ylmeth­oxy)benzene-κ4 N,O,O′,N′]dichloridocopper(II)

In the title compound, [CuCl2(C18H16N2O2)], the CuII atom lies on a twofold axis and is six-coordinated in a distorted octa­hedral environment defined by two N and two O atoms from the ligand and by two Cl atoms. In the crystal, π–π inter­actions [centroid–centroid distance = 3.838 (1) Å] and C—H⋯Cl hydrogen bonds link adjacent mol­ecules into a chain structure along [101]

The Role of Alfalfa and Forage Resources in Crop-Livestock Systems in a Rain-Fed Region of North-Western China

Western China has been facing the challenges of both environmental sustainability and economic development. Current government policies and interventions support the development of integrated crop-livestock production systems for enhancing food security and environment sustainability. Compared with traditional grain-based faming systems, integrated systems have better resource utilisation, however annual forage supply deficits estimated at 1.37 t DM forage/farm are experienced in the region, especially in late winter and early spring. Accordingly, optimising the use of available forage resources is a priority for regional researchers and extension officers, with research seeking pathways for better fodder conservation and greater and more effective use of fodder sources to close the spring feed gap. This paper presents relevant research activities relating to alfalfa (Medicago sativa L.) and winter wheat (Triticum aestivum L.) management in integrated crop-livestock production systems. As the planting of alfalfa is strongly encouraged in northern China, alfalfa species selection and optimised harvesting management are essential to ensure the full benefits of alfalfa are available for livestock intensification. The capacity for a prevalent grain crop, winter wheat to be managed as a dual-purpose fodder and grain source shows potential as a means to alleviate deficits of animal feed supply. The present information expands our understanding of integrated forage-livestock production in rain-fed areas, exploring options that can improve productivity in small-farm households leading to income generation

Fault estimation for time-varying systems with Round-Robin protocol

summary:This paper is concerned with the design problem of finite-horizon $H_\infty$ fault estimator for a class of nonlinear time-varying systems with Round-Robin protocol scheduling. The faults are assumed to occur in a random way governed by a Bernoulli distributed white sequence. The communication between the sensor nodes and fault estimators is implemented via a shared network. In order to prevent the data from collisions, a Round-Robin protocol is utilized to orchestrate the transmission of sensor nodes. By means of the stochastic analysis technique and the completing squares method, a necessary and sufficient condition is established for the existence of fault estimator ensuring that the estimation error dynamics satisfies the prescribed $H_\infty$ constraint. The time-varying parameters of fault estimator are obtained by recursively solving a set of coupled backward Riccati difference equations. A simulation example is given to demonstrate the effectiveness of the proposed design scheme of the fault estimator