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The implementation of an urban growth boundary (UGB) can effectively control urban sprawl and promote efficient land use, which is crucial for future urban development. However, most of existing studies overlook the reuse of existing idle and inefficient land within the city in the delineation of UGBs. With China’s urban construction shifting from incremental development to stock development, this study focuses on Wuhan and presents a set of technical approaches for delineating UGBs with a stock development orientation. First, a built-up area composite index (POI&ISA) is constructed based on point of interest (POI) kernel density analysis and impervious surface index extraction to evaluate constructive levels in 2010 and 2020 and identify the urban vitality zone. Then, we combine the current land use status and control policies to divide the urban spatial development potential into five categories: urban vitality land, urban non-vitality land, other vitality land, other non-vitality land, and restricted development land. Finally, the PLUS model is applied in the analysis of the driving forces of land use change in Wuhan, simulating the UGBs in three stages of incremental development (2020–2030), incremental and stock development (2030–2040), and stock development (2040–2050). Finally, the PLUS model simulation projects the UGB areas to be 436.436 km2, 474.617 km2, and 520.396 km2 for the years 2030, 2040, and 2050, respectively. The predicted timespan of urban development extends up to 30 years, serving as a reliable reference for Wuhan’s long-term and near-term planning.

Poplar buds are characterized by a high content of phenolic compounds, which exhibit a broad spectrum of biological activities. However, the relationship between Chinese propolis and poplar buds based on their antioxidant capacities and underlying mechanisms remains unclear. This study aimed to investigate the antioxidant properties of poplar bud (Populus) extract (PBE) and Chinese propolis (CP) and to elucidate the mechanisms behind their activity. High-performance liquid chromatography (HPLC) analysis revealed that both PBE and CP contain a significant amount of phenolic acids and flavonoids. 2,2-diphenyl-1-picrylhydrazyl (DPPH), 2,2′-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS), and ferric-reducing antioxidant power (FRAP) assays demonstrated that PBE and CP possess excellent antioxidant activity. Furthermore, administration of PBE and CP improved the survival rate of C. elegans under oxidative stress. They also decreased the levels of reactive oxygen species (ROS) and malondialdehyde (MDA), while enhancing the activity of antioxidant enzymes (SOD, CAT). PBE and CP intervention upregulated the expression of key genes daf-16, sod-3, hsp-16.2, and skn-1 in nematodes. This suggests that the antioxidant activity of PBE and CP is dependent on daf-16 and skn-1 signaling pathways. In conclusion, poplar bud extracts ha have the potential to become a substitute for propolis and a potential therapeutic agent for treating diseases associated with oxidative damage.

Rambutan is a tropical tree and its fruit has several favorable characteristics. To understand how the color of the rambutan fruit peel develops, the transcriptome, flavonoid metabolome, and carotenoid metabolome data of two rambutan cultivars, ‘BY2’ and ‘BY7’, which show yellow and red peels at maturity, respectively, were comprehensively analyzed at three developmental stages. We identified 26 carotenoid components and 53 flavonoid components in these cultivars. Anthocyanins were the main component contributing to the red color of ‘BY7’ after reaching ripeness. The carotenoid content decreased sharply as the fruit matured. Hence, we speculated that flavonols were the main contributors to the yellow color of the ‘BY2’ peel. In total, 6805 differentially expressed genes were screened by transcriptome analysis; the majority of them were enriched in metabolic pathways and the biosynthesis of secondary metabolites. Weighted gene co-expression network analysis results revealed that in addition to MYB and bHLH, ERF, WRKY, MYB-related, and C3H were the main potential transcription factors regulating the color of the rambutan peel. In addition, we also identified 12 structural genes associated with flavonoid biosynthesis. The research findings shed light on the molecular mechanisms of color acquisition in rambutan fruit peels, laying the foundation for the quality control of rambutan and the cultivation of differently colored cultivars of rambutan.