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Abstract The material basis for soil formation is rock weathering debris. Understanding the particle size composition characteristics of rock weathering debris and its impacts is important for improving the soil structure of dry farmland in the central dry zone of Ningxia,China. In this study, the particle sizes of weathered debris collected from grey–green slate after indoor simulations of freeze–thaw and dry–wet cycles tests were examined. The results were as follows: (1) Under 16 treatments, the weathering debris of grey–green slate contained about 10% or less very fine sand and coarse silt, while clay, fine silt, and fine sand were the most abundant sizes (at least 60% of the total). (2) Under each treatment, the average particle size of the grey–green slate weathered debris was 5.52Ф (silt grade). The overall skewness was high, but the symmetry was poor. The particle size frequency distribution curve had many broad peaks or multiple peaks. (3) The fractal dimension was associated with very fine silt but had a strong negative correlation with fine sand and medium-coarse sand. The results indicate that fractal dimension can reflect the grain size characteristics of weathered debris. The mineral element content of the grey–green slate somewhat affected the fractal dimension, and it positively correlated with environmental electrical conductivity (EC) and element-leaching amount; it negatively correlated with particle size, temperature, and pH. According to the findings, the fractal dimension can accurately represent the particle size distribution of weathered debris. The generation of grey–green slate weathering debris should be considered in the formation and development of local soil.

[Objectives] To analyze and optimize the crop planting structure in Ningxia based on the shortage of water resources and the large proportion of agricultural water consumption in Ningxia. [Methods] The change trend of crop planting area and planting structure in Ningxia in 2004 -2018 was analyzed, and a multi-objective optimization model was constructed with the objectives of maximum crop profit and minimum water demand. The STEM method was applied to solve the problem, and the optimization scheme of crop planting in Ningxia was obtained. [Results] In Ningxia in 2004 - 2018, the planting area showed the characteristics of "increase-decrease-increase"; the area and proportion of cash crops were increasing, and the proportion of grain crops was gradually decreasing, but the proportion of crops with high water consumption was still high. After the planting structure was optimized, the economic benefit was increased by 34.85 × 108 yuan, and the water demand was reduced by 3.9 x 108 m³. [ Conclusions] Under the premise of ensuring food security, the optimized scheme not only saves water resources but also obtains higher economic benefits. It provides a reference for alleviating water shortage and increasing farmers' income. [ABSTRACT FROM AUTHOR]

Objective: This paper reported 1 case of paradrenal anastomosing hemangioma (AH), and to summarize the clinicopathological features, diagnosis and differential diagnosis of AH. Methods: The clinical data of this patient was collected, the histological morphology and immunohistochemical characteristics were observed and analyzed in combination with relevant literature. Results: The tumor was located in the adipose tissue around the adrenal gland, it was well circumscribed, gray and red colored. Microscopically, the tumor was composed of irregularly anastomosing sinusoidal-like spaces lined by hobnail endothelial cells, focal mild atypia was observed. Intravascular fibrin thrombi and hyaline globules could be seen. Immunohistochemical results showed diffuse staining for endothelial markers, including CD31 and CD34. D2-40, CK5/6, calretinin, CKpan, EMA, Melan-A and HMB45 immunostains were negative. Ki-67 staining indicated a low proliferative activity. Eventually this patient was diagnosed with AH. Conclusions: AH is a rare but distinct type of vascular neoplasm. Owing to its striking anastomosing appearance, it needs to be distinguished from well differentiated angiosarcoma. In addition, the differential diagnosis of urogenital AH also includes angiomyolipoma, adenomatoid tumor, and hemangiomatoid hyperplasia secondary to renal cell carcinoma.