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In purpose of getting the influence of different structural parameters on the bearing characteristics of the conical deformation friction pair, the equivalent contact model of the conical deformation friction pair under different structural parameters is established. The buckling deformation simulation is carried out by Ansys Workbench, and combined with the analysis of the Matlab numerical model, the variation law of the oil film thickness of the friction pair under different structural parameters is obtained. Based on the oil film pressure and micro-convex peak rough contact model, the variation law of the maximum total contact pressure during 10 s soft start is found, and the method of selecting the optimal structural parameters of the friction pair under the actual operating conditions is summarized. The results show that the axial deformation and the increase of the thickness of the steel sheet can make the deformation of the middle diameter of the steel sheet more difficult, and lead to the increase of the maximum total contact pressure of the friction pair. At the same time, it leads to non-uniform contact and non-uniform distribution of contact pressure, and different ratios of inner diameter to outer diameter can only affect the distribution location of the maximum total contact pressure of the friction pair, without having any great influence on its variation law and value. The research results provide a basis for the study of torque characteristics of conical deformation friction pairs under different structural parameters.

The expression of cyclooxygenase 2 (COX-2) was up-regulated and prostaglandin E2 (PGE2) was significantly increased in colon cancer patients. As the main prostaglandin produced by COX-2, PGE2 plays an important role in angiogenesis, survival, invasion and migration of colon cancer cells. The EP4 receptor, as an important transporter of PGE2 signaling, increases the survival and development of colon cancer cells through various mechanisms of overexpression. Signal pathway starting from COX-2, continuing with PGE2 and ending with EP4 can promote the spread and growth of colon cancer. Therefore, targeting the COX-2/PGE2/EP4 axis may be a valuable treatment method for colon cancer. This article outlines the biological activity of COX-2, the mechanism of action of COX-2/PGE2/EP4 as a signal axis in colon cancer, and the research progress of targeted drugs in colon cancer prevention.

Renal cell carcinoma is one of the ten multiple cancers, and its incidence rate and mortality rate have been increasing in more than 20 years. Clear cell renal cell carcinoma (ccRCC) is the most common histopathological subtype. Cyclic ribonucleic acids (circRNAs) are noncoding ribonucleic acids, which are widely distributed with diverse cellular functions and have organ- and tissue-specific expression patterns. Recent studies have shown that circRNAs are abnormally expressed in ccRCC and play an important role in the occurrence and development of ccRCC. However, there are few researches and related mechanisms of circRNAs regulating the biological behavior of ccRCC. Therefore, the paper mainly describes the research progress of circRNAs regulating the biological behavior of ccRCC and discusses its potential as a biomarker for early diagnosis and prognosis of ccRCC and targeted therapy.

The influence of five geometric parameters of a negative Poisson’s ratio honeycomb structure on the cellular arc angle, length of connecting rod, outer thickness, thickness ratio and length-height ratio were studied. By using uniform test design method, the fitting equations of four evaluation indexes, energy absorption, specific energy absorption, peak crushing force and equivalent Poisson’s ratio were obtained. On this basis, the multi-objective optimization design was carried out, and the appropriate cellular geometric parameters were selected. The results show that the cellular arc angle and the length of the connecting rod have great influence on the specific energy absorption of the honeycomb structure, the outer thickness and thickness ratio have great influence on the peak crushing force and energy absorption of the structure, However, the outer thickness under equal strain has little effect on the equivalent Poisson’s ratio of the structure. The energy absorption and equivalent Poisson’s ratio of the structure are greatly affected by the length-height ratio. Compared with the original size, the optimized size comprehensively selected has higher energy absorption, protection and impact resistance effect, and the crushing force is much lower than the original size model and more stable.

Chlorophyll a and b content (Cab) and leaf area index (LAI) are two key parameters of crops, and their quantitative inversions are important for growth monitoring and the field management of wheat. However, due to the close correlation between the spectral signals of these two parameters and the effects of soil and atmospheric conditions, as well as modeling errors, synchronous retrieval of LAI and Cab from remote sensing data is still a challenging task. In a previous study, we introduced the optimal estimation theory and established the inversion framework by coupling the PROSAIL (PROSPECT + SAIL) model with the unified linearized vector radiative transfer model (UNL-VRTM). The framework fully utilizes the simulated radiance spectra for synchronous retrieval of Cab and LAI at the UAV observation scale and has good convergence and self-consistency. In this study, based on this inversion framework, synchronized retrieval of Cab and LAI was carried out by real wheat UAV observation data and validated with the ground-measured data. By comparing with the empirical statistical model constructed by the PROSAIL model and coupled model, least squares support vector machine (LSSVM), and random forest (RF), the proposed method has the highest accuracy of Cab and LAI estimated from UAV multispectral data (for Cab, R2 = 0.835, RMSE = 14.357; for LAI, R2 = 0.892, RMSE = 0.564). Our proposed method enables the fast and efficient estimation of Cab and LAI in multispectral data without prior measurements and training. [ABSTRACT FROM AUTHOR]