Numerical and Experimental Research on Vibration Mechanism of Rotary Compressor

With a typical rotary compressor as the research object, the vibration mechanism of the rotary compressor was analyzed in detail in this work. And according to the work, the formulations of the tangential vibration and the radial vibration were proposed for the rotary compressor. First, the oil film stiffness and the damp coefficient were obtained by coupling the experimental testing method and numerical simulation. Then a dynamics simulation was conducted for the rotor system and the critical speed for the current rotor system was obtained, which was used to judge if the rotor system is a kind of flexible rotor. After that, with the aerodynamic force and the crankshaft deformation under consideration, the electromagnetic force, the electromagnetic torque and the revolution fluctuation rate were calculated and analyzed based on an electromagnetic simulation analysis for the motor of the rotary compressor. Finally, the tangential vibration and the radial vibration on the shell and the reservoir of the rotary compressor were obtained by using a dynamics simulation with the revolution fluctuation rate as the load for the rotor system. Based on the simulation result, the predicted results match well with the experimental test results. This work in this paper and the method used in this work provide a good reference for prediction of the vibration and resolving vibration problem of the rotary compressor

Validation of the GALAD model and establishment of a new model for HCC detection in Chinese patients

BackgroundGALAD model is a statistical model used to estimate the possibility of hepatocellular carcinoma (HCC) in patients with chronic liver disease. Many studies with other ethnic populations have shown that it has high sensitivity and specificity. However, whether this model can be used for Chinese patients remains to be determined. Our study was conducted to verify the performance of GALAD model in a Chinese cohort and construct a new model that is more appropriately for Chinese populations.MethodsThere are total 512 patients enrolled in the study, which can be divided into training set and validation set. 80 patients with primary liver cancer, 139 patients with chronic liver disease and 87 healthy people were included in the training set. Through the ROC(receiver operating characteristic) curve analysis, the recognition performance of GALAD model for liver cancer was evaluated, and the GAADPB model was established by logistic regression, including gender, age, AFP, DCP, total protein, and total bilirubin. The validation set (75 HCC patients and 130 CLD patients) was used to evaluate the performance of the GAADPB model.ResultThe GALAD and GAADPB achieved excellent performance (area under the receiver operating characteristic curve [AUC], 0.925, 0.945), and were better than GAAP, Doylestown, BALAD-2, aMAP, AFP, AFP-L3%, DCP and combined detection of AFP, AFP-L3 and DCP (AUCs: 0.894, 0.870, 0.648, 0.545, 0.879, 0.782, 0.820 and 0.911) for detecting HCC from CLD in the training set. As for early stage of HCC (BCLC 0/A), GAADPB had the best sensitivity compared to GALAD, ADP and DCP (56.3%, 53.1%, 40.6%, 50.0%). GAADPB had better performance than GALAD in the test set, AUC (0.896 vs 0.888).ConclusionsThe new GAADPB model was powerful and stable, with better performance than the GALAD and other models, and it also was promising in the area of HCC prognosis prediction. Further study on the real-world HCC patients in China are needed

P2X4 receptor modulates gut inflammation and favours microbial homeostasis in colitis

Abstract Background Inflammatory bowel disease (IBD) is a non‐specific chronic inflammatory disease of the intestine. In addition to genetic susceptibility, environmental factors and dysregulated host immunity, the gut microbiota is implicated in the pathogenesis of Crohn's disease (CD) or ulcerative colitis (UC), the two primary types of IBD. The P2X4 receptor has been demonstrated to have a crucial role in preventing infection, inflammation, and organ damage. However, it remains unclear whether the P2X4 receptor affects IBD and the underlying mechanisms. Methods Colitis was induced in mice administrated with dextran sodium sulphate (DSS). 16S rDNA sequencing was used to analyze the gut microbiota in knockout and wild‐type mice. Clinical and histopathological parameters were monitored throughout the disease progression. Results Gene Expression Omnibus analysis showed the downregulation of P2RX4 (P2rx4) expression in colonic tissues from patients or mice with IBD. However, its expression at the protein levels was upregulated on day 4 or 6 and then downregulated on day 7 in C57BL/6 mice treated with DSS. Gene ablation of P2rx4 aggravated DSS‐induced colitis accompanying gut microbiota dysbiosis in mice. Moreover, P2X4 receptor‐positive modulator ivermectin alleviated colitis and corrected dysregulated microbiota in wild‐type C57BL/6 mice. Further antibiotic‐treated gut microbiota depletion, cohousing experiment, and fecal microbiota transplantation proved that gut microbiota dysbiosis was associated with the aggravation of colitis in the mouse model initiated by P2rx4. Conclusions Our findings elaborate on an unrevealed etiopathophysiological mechanism by which microbiota dysbiosis induced by the P2X4 receptor influences the development of colitis, indicating that the P2X4 receptor represents a promising target for treating patients with CD and UC