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BACKGROUND: The whole life of a plant is regulated by complex environmental or hormonal signaling networks that control genomic stability, environmental signal transduction, and gene expression affecting plant development and viability. Seed germination, responsible for the transformation from seed to seedling, is a key initiation step in plant growth and is controlled by unique physiological and biochemical processes. It is continuously modulated by various factors including epigenetic modifications, hormone transport, ROS signaling, and interaction among them. ROS showed versatile crucial functions in seed germination including various physiological oxidations to nucleic acid, protein, lipid, or chromatin in the cytoplasm, cell wall, and nucleus. AIM: of review: This review intends to provide novel insights into underlying mechanisms of seed germination especially associated with the ROS, and considers how these versatile regulatory mechanisms can be developed as useful tools for crop improvement. KEY SCIENTIFIC CONCEPTS OF REVIEW: We have summarized the generation and elimination of ROS during seed germination, with a specific focus on uncovering and understanding the mechanisms of seed germination at the level of phytohormones, ROS, and epigenetic switches, as well as the close connections between them. The findings exhibit that ROS plays multiple roles in regulating the ethylene, ABA, and GA homeostasis as well as the Ca2+ signaling, NO signaling, and MAPK cascade in seed germination via either the signal trigger or the oxidative modifier agent. Further, ROS shows the potential in the nuclear genome remodeling and some epigenetic modifiers function, although the detailed mechanisms are unclear in seed germination. We propose that ROS functions as a hub in the complex network regulating seed germination.
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Five new heterobimetallic magnesiates bearing bidentate dianionic pyrrolyl ligands have been synthesized through co-complexation with alkali-metal reagents and di-n-butylmagnesium. Single-crystal X-ray structural analysis of these complexes revealed a variety of intriguing bonding modes. These alkali-metal (Li, Na, and K) organomagnesiates were utilized as catalysts for cross-coupling Tishchenko reactions with two different aldehydes. The sodium alkyl magnesiate complex {nBuMg[2-(Me3CNCH2)C4H3N]Na(Et2O)}∞ (3) was identified as a competent catalyst, as it exhibited higher catalytic activities and chemoselectivity under mild conditions.
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Although buffer zones around aquatic areas are a useful method for controlling non-point source pollution and restoring natural ecosystem services, proper delineation methods for lakes remain poorly defined, restricting their protection and the rational utilization of resources. As the width of lake buffer zones should be set to meet the area's functional targets and requirements, this study proposes a methodology for delineating these zones that includes critical source areas for non-point source pollution and ecologically sensitive areas. The proposed method was tested on Zhushan Bay, Lake Tai, China given its poor environmental condition and a renewed focus on mitigation by the local government. Data sources and relative processing methods include vector data on land use and hydrographic networks processed by ArcGIS, digital elevation model (DEM) data with 30â¯m resolution, soil and socioeconomic data from local governmental statistical yearbooks, NPS pollution load into lake obtained by literatures and field survey. The results showed that a minimum buffer range could be practically determined while meeting the requirements of both environmental protection and economic needs, providing a theoretical and practical basis for the improved delineation and management of lake buffer zones in watersheds dominated by non-point source pollution.
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The exploration of co-complexation reactions between alkai-metal reagents and ZnEt2 with bidentate aminopyrrolyl ligands afforded a series of alkali-metal (Li, Na, K) alkyl zincates with a variety of intriguing structures, ranging from molecular complexes to more coordination polymers. All aforementioned complexes have been characterized by X-ray crystallography, NMR, IR and UV-vis spectroscopy.
