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SUMMARY Presilphiperfolane‐type sesquiterpenes represent a unique group of atypical sesquiterpenoids characterized by their distinctive tricyclic structure. They have significant potential as lead compounds for pharmaceutical and agrochemical development. Herein, we utilized a transcriptomic approach to identify a terpene synthase (TPS) gene responsible for the biosynthesis of rare presilphiperfolane‐type sesquiterpenes in Inula lineariifolia, designated as IlTPS1. Through phylogenetic analysis, we have identified the evolutionary conservation of key motifs, including RR(x)8W, DDxxD, and NSE/DTE in IlTPS1, which are shared with other tricyclic sesquiterpene synthases in the TPS‐a subfamily of Asteraceae plants. Subsequent biochemical characterization of recombinant IlTPS1 revealed it to be a multiproduct enzyme responsible for the synthesis of various tricyclic sesquiterpene alcohols from farnesyl diphosphate (FPP), resulting in production of seven distinct sesquiterpenes. Mass spectrometry and nuclear magnetic resonance (NMR) spectrometry identified presilphiperfolan‐8β‐ol and presilphiperfol‐7‐ene as predominant products. Furthermore, biological activity assays revealed that the products from IlTPS1 exhibited a potent antifungal activity against Nigrospora oryzae. Our study represents a significant advancement as it not only functionally identifies the first step enzyme in presilphiperfolane biosynthesis but also establishes the heterologous bioproduction of these unique sesquiterpenes. [ABSTRACT FROM AUTHOR]

Rural livelihood resilience (RLR) is significant for the sustainability of rural areas, farmers and agriculture. This research takes the mountainous areas of Southwest China as the study areas and integrates the buffer, adjustment and renewal capabilities to construct a RLR analysis framework and evaluation indicator system. The RLR of 234 sample counties was evaluated using set pair analysis, and the influencing factors of RLR were investigated using Geodetector. The aim is to scientifically analyze the vertical spatial differentiation and influencing factors of RLR and fully explore the risk-resistant potential of rural livelihood systems in mountainous areas. The results show that (1) From 2000 to 2020, RLR increases significantly, but the level is still low, and its structure shows a primary pattern of "buffer capability > adjustment capability > renewal capability". (2) There is no significant negative correlation between RLR and terrain gradients, especially in the middle and low mountains. RLR in high mountainous areas is significantly lower than in low and medium mountainous areas, but the gap is narrowing. There are no significant gaps in RLR and various capabilities between low and medium mountain areas. (3) Economic development, non-agricultural industries and grassroots autonomous organizations are essential determinants for RLR. Economic development, grassroots autonomous organizations and transportation conditions are more important in low and medium mountain areas, while non-agricultural industries and medical conditions contribute more to high mountainous areas. (4) To enhance the RLR, policy recommendations should place a strong emphasis on extending the agricultural industry chain, improving rural production and living infrastructure and strengthening the supply of high-quality social public services. The findings can provide a scientific basis for governments to implement rural revitalization strategies and improve farmers' well-being, as well as practical guidance for enhancing the risk resistance ability of underdeveloped mountainous rural areas. [ABSTRACT FROM AUTHOR]

With the acceleration of urbanization and profound socioeconomic changes, the influx of people from various social strata into cities has led to the phenomenon of residential segregation. Currently, the international community has accumulated profound theoretical foundations and rich practical experiences in the study of residential segregation. This research, primarily based on the WOS literature database, sorts and summarizes relevant studies on residential segregation in recent years (focusing on publications from 2020 to 2024), emphasizing the following four key aspects: (1) tracing the evolution of the theory of residential segregation and analytical methods; (2) analyzing the main characteristics of urban residential segregation; (3) exploring the driving mechanisms and effects of urban residential segregation; and (4) summarizing research trends and providing future perspectives. This study aids urban planners in more accurately identifying areas and characteristics of residential segregation, optimizing urban layouts, and providing richer and more in-depth theoretical support and practical guidance for the field of urban planning science. [ABSTRACT FROM AUTHOR]

As an important ecological ecotone of water and land ecosystems, the lakeside is characterized by a variety ecosystem services and high vulnerability. Forest land is important in resolving the ecological risks of the lakeside area and building its ecological base. It is important to explore the effect of change in forest land on landscape ecological risk in the lakeside area, alleviate the contradiction between ecological protection and construction and development in the area, and realize sustainable development. The present study attempted to explore the spatial and temporal evolutionary features of forest land in the Erhai rim region from 2000 to 2020 using bivariate spatial autocorrelation and multi-scale geographical weighted regression (MGWR) models. The following are the findings of this investigation of the 2000–2020 period: (1) the forest land area in the region generally decreased, first increasing and then decreasing, and was mainly occupied by cultivated land and artificial surfaces; (2) the total landscape ecological risk in the region presented an upward trend, and medium- and higher-risk areas were the main risk areas, with the latter increasing; (3) the impact of forest land expansion and contraction intensity on landscape ecological risk exhibited spatial and temporal heterogeneity. The main forms of forest land change at different stages differed, and the impacts on landscape ecological risk were also different. Reasonable forest land expansion can effectively alleviate the growth in landscape ecological risk, whereas the shrinkage of forest land would aggravate the landscape ecological risk in the Erhai rim region. Moreover, the findings can offer reference for the exploration of ecological protection and coordinated optimization of economic development in Erhai Lake. [ABSTRACT FROM AUTHOR]

The abandonment degree of an urban residential building can reflect the popularity of residential areas. This study uses this idea as a basis for proposing the concept of using residential quarters' abandonment rate to measure the abandonment degree of an area. The spatial pattern of the abandonment rate and its clustering characteristics were obtained by taking 2517 residential quarters in Kunming's Main Urban District as research object, and using their listing for sale ratio data. Thereafter, curve estimation was used to explore the influencing factors of abandonment rate. The results are as follows. (1) The abandonment rate of the four circles in Kunming's Main Urban District increases from inside to outside, showing the pattern of the core area–second ring area–third ring area–new urban district, with evident "core–edge" characteristics. (2) The relationship between distance from the city center, housing ages, and abandonment rate can be well fitted using a quadratic function and shows an inverted "U"-shaped "rising–declining" trend. The relationship between housing prices and abandonment rate is fitted by the inverse function, showing an evident "up" trend. This study is a reference for managers of relevant departments and urban planners in formulating reasonable urban housing development policies. [ABSTRACT FROM AUTHOR]