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With the characteristics of wear resistance， corrosion resistance， improved biocompatibility and antibacterial properties， the micropits array structure has been widely used.femtosecond laser has unique advantages in high-quality micro pit processing， because of its unique ultra-fast processing effect.In this work， Random Forest Regression (RFR) algorithm and Artificial Neural Network (ANN) algorithm were applied to predict the geometry and quality of micro-pit arrays processed by femtosecond laser.Additionally， the effects of laser processing parameters on the diameter， depth and surface roughness (Ra) of micro-pits were analyzed.The predictive capabilities of the RFR and ANN models were evaluated through the root mean square error， coefficient of determination and mean absolute error.Results showed that the overall prediction accuracy of ANN model was slightly higher than RFR model.The R2 for ANN model was 0.81.For diameter， depth and surface roughness， the R2 was 0.67， 0.79 and 0.85， respectively.Data augmentation method was applied to augment the dataset， and the ANN model prediction accuracy was further improved after data augmentation.The overall R2 increased to 0.91.The R2 for diameter， depth and surface roughness was 0.81， 0.91 and 0.95， respectively.In general， the ANN model had better prediction performance than Random Forest in predicting micro pit arrays processed by femtosecond laser processing.As the amount of data increased， this advantage became more obvious， which further verified the potential of the ANN model.

Sichuan hilly area is located in southwest China, which have many hilly area, is a densely populated, economically active, frequent geological disasters area. In this paper, Neijiang City in the region is taken as the test sample. This article, which analyzes Land-Use and Land-Cover Changes (LUCC), meteorological and hydrological data from 2015 to 2020, takes Neijiang City in this region as the research object. We explored the relationship between geological disasters such as collapse and landslides that often occur in the natural ecological environment with LUCC and meteorological and hydrological factors, using GIS spatial analysis and statistical analysis methods. The research results indicate that geological disasters mainly occur in farmland areas. The density of geological disaster points is highest within urban areas, making them the most prone to geological disasters. Geological disasters are more densely distributed in the area within 600 to 800 m from the river. There is a strong correlation between the average rainfall amount and the probability of geological disasters occurring. This study provides a scientific basis for the geological disaster risk assessment, prevention and control in this region. It has certain reference significance for the ecological environment governance, land resources planning and management in other similar regions.

Bisphenol A (BPA) exposure is known to cause damage to male fertility. Conversely, melatonin (MLT) has been shown to offer protection against reproductive damage by acting as an antioxidant. Exploration into the molecular mechanisms behind how MLT alleviates BPA-induced male fertility damage remains unclear. In this study, adult male mice were divided into four groups of control, BPA exposure (intragastrically, 50 mg/kg/day), MLT treatment (intraperitoneal injection, 10 mg/kg/day) and combined BPA+MLT treatment group for comparative analysis after five weeks of treatment. BPA exposure led to male mice subfertility characterized by poor sperm quality of decreased sperm counts and motility, and reduced pregnancy rate of female mice in in vivo and blastocyst formation in vitro experiments. In BPA exposed mice, germ cell proliferation was impaired, showing a decrease in PCNA expression. BPA exposure also induced a decrease in the expression of antioxidant molecules Cat, Prdx6, and Sod1, and up-regulated BAX expression. These expression changes resulted in increased germ cell apoptosis detected by TUNEL experiments. MLT treatment significantly maintained male mice sperm quality and fertility adversely affected by BPA through modulating the abovementioned responses. Sperm proteomics identified 118 BPA-regulated proteins whose expression was changed by MLT treatment, including 37 down-regulated proteins related to proteolysis activity, the up-regulated proteins were mainly involved in lipid metabolism. Conclusively, BPA exposure impaired male fertility by negatively affecting germ cell proliferation and sperm quality. MLT treatment could alleviate the side effects of BPA by regulating antioxidant molecules, inhibiting germ cell apoptosis, and maintaining male fertility. This study will provide more information for further exploration into the molecular mechanisms of BPA and MLT in male reproduction.