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In recent years, the rapid improvement in the urbanization level of the Central Plains urban agglomeration is bound to bring about significant changes in urban land expansion and economic development. However, at present, there is little attention paid to the research on the spatiotemporal interaction characteristics of urban expansion and the interaction between urban expansion and economic development in this region, and existing research lacks a geographical analysis perspective. This study uses spatial autocorrelation, hot spot analysis, LISA time path, and standard deviation ellipse models to analyze the spatiotemporal interaction characteristics of urban expansion in the Central Plains urban agglomeration from 1990 to 2020, and it uses bilateral spatial autocorrelation and decoupling models to analyze the spatial correlation and decoupling effects of urban expansion and economic development. The results show that (1) the urban built-up area of the Central Plains urban agglomeration as a whole is growing in a "J" shape, and the expansion rate has increased rapidly in the past 10 years. (2) The spatial expansion of the city is mainly in the direction of "northwest–southeast"; the directionality has been gradually strengthened in the past 10 years, mainly in the direction of several prefecture-level cities under the jurisdiction of Anhui Province, and the spatial center of gravity of the city has shifted significantly to the south. (3) The spatial agglomeration characteristics of urban expansion in the Central Plains urban agglomeration are not obvious; local hot spots are concentrated in Jiaozuo and its surrounding areas, and urban expansion has local spatial structural instability. (4) During the 2005–2020 period, the risk of uncoordinated urban expansion and economic growth in the Central Plains urban agglomeration increased. This study is of great significance for the rational control of regional development, providing empirical reference for the formulation of the development planning of the Central Plains urban agglomeration, as well as providing a reference for research ideas and methods related to urbanization. [ABSTRACT FROM AUTHOR]

In this study, we aimed to determine the complete nucleotide sequences of the chloroplast genomes of Medicago sativa L. and Medicago falcata L. and perform their phylogenomic analysis. The chloroplast genomes of M. Sativa and M. falcata were found to be 125,095 and 125,810 bp in length, respectively. Additionally, the AT contents of M. Sativa and M. falcata are 66.1% and 66.2%, respectively. Each chloroplast genome contained the same 109 unique genes, including 29 transfer RNA genes, 4 ribosomal RNA genes, and 76 protein-coding genes. Phylogenomic analysis based on complete chloroplast genomes from the Medicago showed that the geographical environment has no significant effect on their genomic composition.