Spinor Walls in Five-Dimensional Warped Spacetime

We study domain wall solutions of a real spinor field coupling with gravitation in five dimensions. We find that the nonlinear spinor field supports a class of soliton configurations which could be viewed as a wall embedded in five dimensions. We begin with an illuminating solution of the spinor field in the absence of gravitation. In a further investigation, we exhibit three sets of solutions of the spinor field with nonconstant curvature bulk spacetimes and three sets of solutions corresponding to three constant curvature bulk spacetimes. We demonstrate that some of these solutions in specific conditions have the energy density distributions of domain walls for the spinor field, where the scalar curvature is regular everywhere. Therefore, the configurations of these walls can be interpreted as spinor walls which are interesting spinor field realizations of domain walls. In order to investigate the stability of these spinor configurations, the linear perturbations are considered. The localization of the zero mode of tensor perturbation is also discussed.Comment: 31 pages,5 figure

3-(Pyridin-2-yl)coumarin

In the title compound, C14H9NO2, the dihedral angle between the pyridine ring and the lactone ring is 10.40 (3)°. The coumarin ring system is nearly planar, with a dihedral angle of 1.40 (2)° between the lactone and benzene rings. An intra­molecular C—H⋯O hydrogen bond occurs. In the crystal, inversion dimers linked by pairs of C—H⋯O inter­actions occur, generating R 2 2(14) loops

Effect of Visceral Fat Index on Perioperative Efficacy of Laparoscopic Radical Resection for Colorectal Cancer

Purpose: To investigate the effect of visceral fat index (VAI) on perioperative period after radical resection of colorectal cancer, and analyze the relationship between VAI and postoperative complications. At the same time, we also discussed whether the correlation between VAI and complications is superior to body mass index (BMI), waist circumference (WC), triglyceride (TG), high-density lipoprotein (HDL) and other common body fat indicators. Methods: From October 2021 to June 2022, 178 colorectal cancer patients in the Gastrointestinal Surgery Department of the First Affiliated Hospital of Chongqing Medical University were collected. Various indexes of patients were obtained through preoperative physical examination and blood examination. VAI value was calculated by formula, because of the high triglyceride-waist-circumference phenotype (increased waist circumference and hypertriglyceridemia) and visceral fat index (Vai, assessed according to waist circumference, body mass index, triglyceride and high-density lipoprotein cholesterol) , it is considered a cheap and effective marker for visceral (intra-abdominal) obesity and metabolic disorders. and then divided into groups according to dichotomy. Because the visceral index grade was divided into a total of 30 grades, according to grade, into the high VAI value group (VAI grade more than 15 grades) and the low VAI group (no more than 4 grades), with 89 patients in the high VAI group; There were 89 patients in the low VAI group. The relationship between VAI value and postoperative complications of patients was discussed by using statistical methods, and whether it was better than other body fat indexes was further analyzed. Results: 178 patients met the inclusion criteria and were divided into 89 patients in the high VAI group and 89 patients in the low VAI group according to the dichotomy. In patients with high VAI value, the operation time was significantly prolonged (213.01 ± 63.67 vs 190.34 ± 68.69 p=0.02), and the tumor N stage was higher (p=0.04). The results of ROC curve revealed that the area under the curve of VAI value was larger than that of BMI, waist circumference, triglyceride and high-density lipoprotein, suggesting that the value of VAI value was higher in diagnosis. Conclusions: The increase of VAI can prolong the operation time of colorectal cancer patients undergoing radical surgery, affect the recovery of the body after surgery, and increase the risk of complications. At the same time, compared with BMI, waist circumference, triglyceride and high-density lipoprotein, VAI has a better prediction effect on complications, which can be popularized in clinical work

Convergent Analysis of Energy Conservative Algorithm for the Nonlinear Schrödinger Equation

Using average vector field method in time and Fourier pseudospectral method in space, we obtain an energy-preserving scheme for the nonlinear Schrödinger equation. We prove that the proposed method conserves the discrete global energy exactly. A deduction argument is used to prove that the numerical solution is convergent to the exact solution in discrete L2 norm. Some numerical results are reported to illustrate the efficiency of the numerical scheme in preserving the energy conservation law

A Comparative Study on Improved Arrhenius-Type and Artificial Neural Network Models to Predict High-Temperature Flow Behaviors in 20MnNiMo Alloy

The stress-strain data of 20MnNiMo alloy were collected from a series of hot compressions on Gleeble-1500 thermal-mechanical simulator in the temperature range of 1173∼1473 K and strain rate range of 0.01∼10 s−1. Based on the experimental data, the improved Arrhenius-type constitutive model and the artificial neural network (ANN) model were established to predict the high temperature flow stress of as-cast 20MnNiMo alloy. The accuracy and reliability of the improved Arrhenius-type model and the trained ANN model were further evaluated in terms of the correlation coefficient (R), the average absolute relative error (AARE), and the relative error (η). For the former, R and AARE were found to be 0.9954 and 5.26%, respectively, while, for the latter, 0.9997 and 1.02%, respectively. The relative errors (η) of the improved Arrhenius-type model and the ANN model were, respectively, in the range of −39.99%∼35.05% and −3.77%∼16.74%. As for the former, only 16.3% of the test data set possesses η-values within ±1%, while, as for the latter, more than 79% possesses. The results indicate that the ANN model presents a higher predictable ability than the improved Arrhenius-type constitutive model