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• Drug repositioning development is a common and effective method for discovering new drug candidates. • Novel ibuprofen-furo[2,3- d ]pyrimidine bearing triazole, hydrazide and oxadiazole hybrid derivatives were synthesized and evaluated for their antitumor activities. • All target compounds exhibited potent antitumor activity. • Target prediction results displayed that target compound 9b may be a G protein-coupled receptors CCR3 inhibitor. In this study, building upon the ibuprofen lead compound and previous research on antitumor agents, 33 novel ibuprofen-furo[2,3- d ]pyrimidine bearing triazole, hydrazide and oxadiazole hybrid derivatives were synthesized. The all compounds were confirmed structurally using 1H NMR, 13C NMR, and HR-MS. Subsequently, the antitumor activities of these compounds were evaluated on HepG2 and A549 cell lines in vitro. The findings indicated that all target compounds exhibited potent antitumor activity. A preliminary comparison among different pharmacophores of 3a - 3h, 6a - 6g, 9a - 9m , and 10a - 10e revealed a general trend: triazole > hydrazide/bishydrazide > oxadiazole in terms of activity. Additionally, for compounds 9a - 9m , substituents at the C-4 position of the pyrimidine ring demonstrated significant effects on activity, with the order of potency being piperidin-1-yl > morpholin-1-yl > diethylamino > di-n-propyl amino. Furthermore, the representative compound 9b was selected to explore its impact on HepG2 and A549 cell apoptosis, and the results indicated that 9b typically caused cell apoptosis in a dose-dependent manner. Further target prediction results displayed that 9b may be a G protein-coupled receptors CCR3 inhibitor. Ultimately, compound 9b showed excellent antitumor activity against HepG2 and A549 cell lines with IC 50 values of 0.144μmol/L and 0.068μmol/L, respectively, making it a promising antitumor candidate for further study. [Display omitted] [ABSTRACT FROM AUTHOR]

Within the past decades, the karst region in the Guangxi province in southwest China has been in the focus of large scale ecological restoration projects. In this study, we adapt the pressure-state-response (PSR) framework (which includes measures for human pressure, the current state of the ecosystem and the human response) and propose a remote sensing based ecosystem health (ESH) index (0–1; 250 m spatial resolution), evaluating the pressure and state of the fragile karst ecosystem. We further apply inventory data of recovery actions (restoration areas at county level resolution) as response to ongoing degradation to test the impact of ecological restoration on the ESH. Our analysis was conducted for the years 2000, 2010 and 2016, and the results showed that 73% of the study area experienced an increase in the ESH (from 2000 to 2016) which was related to the improvements in vegetation vigor, organization, resilience, ecosystem service provisioning which offset a deterioration in fragmentation and population density. From 2000 to 2016, areas of increase in ESH were slightly larger in karst than in non-karst (37.5% and 35.1%, respectively), but also larger areas of decrease in ESH were observed in karst as compared to non-karst (16% and 11%, respectively). The results further showed that the share of areas with a high ESH (greater than 0.7) had increased by ∼3% (from 67.16% to 70.21%) during the 17 years period. At county level, we found a clear relationship between increases in ESH and ecological restoration areas ( r  = 0.58 , p  = 0.004), with a high recovery rate (ratio between areas with increased ESH and restoration areas in a county) in karst than in non-karst. We conclude that restoration projects have caused a large scale transformation of farmland into forested areas (∼5500 km 2 ), which has caused a general improvement in ecosystem parameters related to ESH. [ABSTRACT FROM AUTHOR]

Identifying the best management practices (BMPs) for reducing nitrous oxide (N 2 O) emissions in tea field poses challenges due to numerous economic and environmental objectives involved, alongside intricate trade-off relationships amongst them, particularly within the context of climate change. This study proposed a hybrid approach that integrates field observations, the WNMM agroecosystem model, and the NSGA-III optimization algorithm. This integrated method aimed to comprehensively optimize fertilizer application (including rate, type, and method) and nitrification inhibitor addition in order to maximize crop yield potential and minimize N 2 O emissions, while also to enhance nitrogen (N) use efficiency (NUE), reduce N loss through leaching and volatilization, and minimize changes in soil organic matter in tea fields of subtropical Central China. The optimized fertilizer application rates based on Pareto fronts for the historical period (1985–2021), SSP2–4.5 (2023–2100) and SSP5–8.5 (2023–2100) are considerably lower than the practices commonly employed by local farmers (450 kg N ha−1). Specifically, the optimized rates meeting the dual objectives of stabling yield (> 3825 kg ha−1) and reducing N 2 O emissions (< 4.73 kg N ha−1) are even lower, accounting for 33–38 % of the local rate. Importantly, under the conditions of future climate warming, a combination of intercropping sorghum and deep placement of fertilizers is necessary to realize effective many-objective optimization for N 2 O reduction. However, controlled-release fertilizers show a limited effect on N 2 O emission reduction. In summary, this study illustrated the significant potential of implementing many-objective optimized management practices to save fertilizer and reduce N 2 O emissions without compromising crop yield in tea field. Importantly, the adoption of specific practices such as intercropping sorghum and implementing deep placement of fertilizers can be effective strategies to address climate change-related issues, including N leaching, volatilization, and soil organic matter loss. These findings offer valuable theoretical guidance for tea farmers and local governments. • The validated WNMM exhibited strong performance in predicting N 2 O emissions within subtropical tea field system. • Significant opportunities exist to save fertilizer and mitigate N 2 O while maintaining crop yield amidst climate change. • The optimized N rates for historical and future climate scenarios were considerably lower than the conventional practices. • A combination of BNI and DP was essential to reduce N 2 O emissions amidst future climate warming conditions. [ABSTRACT FROM AUTHOR]

The karst area in southwest China is, in recent decades, one of the world's regions with the fastest vegetation growth and increase in aboveground biomass. The improvement in the ecological conditions within this region can, to a large extent, be attributed to ecological protection projects. However, it remains unclear whether the observed increase in vegetation cover could mitigate rocky desertification at large scale. In this study, we utilized information from large field campaigns in the years 2005, 2011, and 2016, supported by satellite imagery interpretation and statistics on ecological protection projects, to explore the impact of restoration efforts on rocky desertification mitigation and vegetation resilience/resistance. The results show that restoration efforts caused a net decrease of 26.14% in areas affected by rocky desertification from 2005 to 2016. The larger the restoration efforts, the stronger the decrease in rocky desertification areas, and also the vulnerability of landscapes towards desertification; the probability of rocky desertification occurring decreased almost linearly with increased restoration efforts. In addition, both vegetation resilience and resistance against climate variations increased with restoration efforts. Restoration efforts were mainly responsible for the recovery of the ecosystem, showing that human impact is the main driver for the reversal of rocky desertification. Our study provides scientific evidence on rocky desertification control being an important step towards a sustainable development of the landscapes of Southwest China. [ABSTRACT FROM AUTHOR]

A series of diverse furo[2,3-d]pyrimidines (2a–2b, 4a–4d and 8a–8c) and benzofuro[3,2-d]pyrimidines (12a–12c) were synthesized and screened for their antitumor effects against HepG2, Bel-7402 and HeLa cell lines in vitro. Representatively, 4a, with an IC50 of 0.70 μM, exhibited the best antitumor activity against the tested HepG2 cell lines. Molecular docking investigation further revealed the possible binding modes of compound 4a with receptor tyrosine kinase. Preliminary results indicated that the title compounds were helpful as leading structures for preparing a new antitumor drug. [ABSTRACT FROM AUTHOR]

To alleviate the severe rocky desertification and improve the ecological degradation conditions in Southwest China, the national and local Chinese governments have implemented a series of Ecological Restoration Projects (ERPs) since the late 1990s. This study proposed a remote sensing based approach to evaluate the long-term efforts of the ERPs started in 2000. The method applies a time-series trend analysis of satellite based vegetation data corrected for climatic influences to reveal human induced vegetation changes. The improved residual method is combined with statistics on the invested project funds to derive an index, Project Effectiveness Index (PEI), measuring the project effectiveness at county scale. High effectiveness is detected in the Guangxi Province, moderate effectiveness in the Guizhou Province, and low and no effectiveness in the Yunnan Province. Successful implementations are closely related to the combined influences from climatic conditions and human management. The landforms of Peak Forest Plain and Peak Cluster Depression regions in the Guangxi Province are characterized by temperate climate with sufficient rainfall generally leading to a high effectiveness. For the karst regions of the Yunnan and Guizhou Provinces with rough terrain and lower rainfall combined with poor management practices (unsuitable species selection, low compensation rate for peasants), only low or even no effect of project implementations can be observed. However, the effectiveness distribution is not homogeneous and counties with high project effectiveness in spite of complex natural conditions were identified, while counties with negative vegetation trends despite relatively favorable conditions and high investments were also distinguished. The proposed framework is expected to be of high relevance in general monitoring of the successfulness of ecological conservation projects in relation to invested funds. [ABSTRACT FROM AUTHOR]

Under the transformation from over-cultivation to ecological protection in China's karst, how human activities affect ecosystem services should be studied. This study combined satellite imagery and ecosystem models (Carnegie-Ames-Stanford Approach (CASA), Revised Universal Soil Loss Equation (RUSLE) and Integrated Valuation of Ecosystem Services and Trade-offs (InVEST)) to evaluate primary ecosystem services (net ecosystem productivity (NEP), soil conservation and water yield) in a typical karst region (Huanjiang County). The relationships between human activities and ecosystem services were also examined. NEP increased from 441.7 g C/m2/yr in 2005 to 582.19 g C/m2/yr in 2015. Soil conservation also increased from 4.7 ton/ha to 5.5 ton/ha. Vegetation recovery and the conversion of farmland to forest, driven largely by restoration programs, contributed to this change. A positive relationship between increases in NEP, soil conservation and rural-urban migration (r = 0.62 and 0.53, P < 0.01, respectively) indicated decreasing human dependence on land reclamation and naturally regenerated vegetation. However, declining water yield from 784.3 to 724.5 mm highlights the trade-off between carbon sequestration and water yield should be considered. Our study suggests that conservation is critical to vegetation recovery in this region and that easing human pressure on land will play an important role. [ABSTRACT FROM AUTHOR]