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In order to investigate the changes in soil enzyme activity and their influencing factors in coal mining subsidence areas with high underground water levels, in this study, we collected soil samples at different depths (SL: 0–20 cm; ML: 20–40 cm; DL: 40–60 cm) in a deep coal seam subsidence area (T1), a shallow coal seam subsidence area (T2), and control non-subsidence areas (W1 and W2) in eastern China. Soil physicochemical properties and enzyme activities were determined, and the mechanism of the latter's response to coal mining subsidence was investigated based on correlation analysis, redundancy analysis, and structural equation modeling. The results show the following: (1) In the coal mining subsidence areas, the soil pH value (pH), soil available nitrogen (AN), available phosphorus (AP), available potassium (AK), and soil organic matter (SOM) contents were lower than those in the non-subsidence areas, while the soil water content (SWC) and bulk density (BD) were higher than those in the non-subsidence areas and increased with depth. (2) The activities of soil urease (URE), sucrase (SUC), alkaline phosphatase (ALP), and catalase (CAT) gradually decreased with depth and were all lower than those in the non-subsidence areas; the largest decreases with respect to the latter were 24.33%, 18.73%, 38.89%, and 5.88%, respectively. (3) The soil nutrient environment had a highly significant and direct positive effect on enzyme activity, with AN, AP, and SOM contents having the greatest impact. (4) Soil BD had a highly significant and direct negative effect and an indirect negative effect (by affecting nutrients) on enzyme activity. The results of this study on the effects of soil physicochemical properties on enzyme activity provide a basis for the ecological restoration of mines. [ABSTRACT FROM AUTHOR]

In order to solve the problem of inconsistent moisture content in particles during the drying process of tiger nuts (Cyperus esculentus) due to uneven air flow and temperature distribution in the drying chamber, an open-hole corner box was designed based on the principle of negative pressure micro-perforated air supply. Using computational fluid dynamics (CFD) and discrete element method (DEM) simulation, coupled with the basic theory of interphase heat and mass transfer, a mathematical model for interphase heat and moisture coupling transfer was established. The effects of different aperture rates of corner boxes in the drying chamber, spatial location arrangement, and other related variables on the airfield distribution, temperature field distribution, tiger nut temperature, and moisture content changes were investigated. The results show that the average air velocity below the air inlet gradually increases as the opening ratio increases. When the opening rate is 0.33%, the wind field uniformity is better, and the inhomogeneity of the drying chamber wind field is improved. As the lateral distance increases, the consistency of the moisture content distribution increases and then decreases, and the flow rate of the tiger nuts gradually increases when the grain is discharged. The rate of decrease in water content decreases gradually with the increase in longitudinal distance. When the wind speed reaches 4 m/s, the drying chamber wind field is more uniform, and the water vapor diffusion efficiency at the outlet is basically the same. Therefore, the appropriate corner box has a horizontal distance of 320 mm and a longitudinal distance of 420 mm, providing a basis for the design of tiger nut drying equipment. [ABSTRACT FROM AUTHOR]

Guppies are small tropical fish with brightly colored bodies and variable tail shapes. There are two phenotypes of domestic guppy eye color: red and black. The wild type is black-eyed. The main object of this study was to identify candidate genes for the red-eyed phenotype in domestic guppies. We hope to provide molecular genetic information for the development of new domestic guppy strains. Additionally, the results also contribute to basic research concerning guppies. In this study, 121 domestic guppies were used for genomic analysis (GWAS), and 44 genes were identified. Furthermore, 21 domestic guppies were used for transcriptomic analysis, and 874 differentially expressed genes (DEGs) were identified, including 357 upregulated and 517 downregulated genes. Through GO and KEGG enrichment, we identified some important terms or pathways mainly related to melanin biosynthesis and ion transport. qRT-PCR was also performed to verify the differential expression levels of four important candidate genes (TYR, OCA2, SLC45A2, and SLC24A5) between red-eyed and black-eyed guppies. Based on the results of genomic and transcriptomic analyses, we propose that OCA2 is the most important candidate gene for the red-eyed phenotype in guppies. [ABSTRACT FROM AUTHOR]

Proliferation, apoptosis, and steroid hormone secretion by granulosa cells (GCs) and theca cells (TCs) are essential for maintaining the fate of chicken follicles. Our previous study showed that the Wnt inhibitor factor 1 (WIF1) plays a role in follicle selection. However, the significance of WIF1 in GC- and TC-associated follicular development was not explicitly investigated. This study found that WIF1 expression was strongly downregulated during follicle selection (p < 0.05) and was significantly higher in GCs than in TCs (p < 0.05). WIF1 inhibits proliferation and promotes apoptosis in GCs. Additionally, it promotes progesterone secretion in prehierarchal GCs (pre-GCs, 1.16 ± 0.05 ng/mg vs. 1.58 ng/mg ± 0.12, p < 0.05) and hierarchal GCs (hie-GCs, 395.00 ng/mg ± 34.73 vs. 527.77 ng/mg ± 27.19, p < 0.05) with the participation of the follicle-stimulating hormone (FSH). WIF1 affected canonical Wnt pathways and phosphorylated β-catenin expression in GCs. Furthermore, 604 upregulated differentially expressed genes (DEGs) and 360 downregulated DEGs in WIF1-overexpressed GCs were found through RNA-seq analysis (criteria: | log 2 ⁡ (F o l d C h a n g e) | > 1 and p_adj < 0.05). Cytokine–cytokine receptor interaction and the steroid hormone biosynthesis pathway were identified. In addition, the transcript of estrogen receptor 2 (ESR2) increased significantly ( log 2 ⁡ (F o l d C h a n g e) = 1.27, p_adj < 0.05). Furthermore, we found that WIF1 regulated progesterone synthesis by upregulating ESR2 expression in GCs. Additionally, WIF1 suppressed proliferation and promoted apoptosis in TCs. Taken together, these results reveal that WIF1 stimulates follicle development by promoting GC differentiation and progesterone synthesis, which provides an insight into the molecular mechanism of follicle selection and egg-laying performance in poultry. [ABSTRACT FROM AUTHOR]