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SUMMARY: Acacetin, a flavonoid compound, possesses a wide range of pharmacological effects, including antimicrobial, immune regulation, and anticancer effects. Some key steps in its biosynthetic pathway were largely unknown in flowering plants. Here, we present the first haplotype‐resolved genome of Chrysanthemum indicum, whose dried flowers contain abundant flavonoids and have been utilized as traditional Chinese medicine. Various phylogenetic analyses revealed almost equal proportion of three tree topologies among three Chrysanthemum species (C. indicum, C. nankingense, and C. lavandulifolium), indicating that frequent gene flow among Chrysanthemum species or incomplete lineage sorting due to rapid speciation might contribute to conflict topologies. The expanded gene families in C. indicum were associated with oxidative functions. Through comprehensive candidate gene screening, we identified five flavonoid O‐methyltransferase (FOMT) candidates, which were highly expressed in flowers and whose expressional levels were significantly correlated with the content of acacetin. Further experiments validated two FOMTs (CI02A009970 and CI03A006662) were capable of catalyzing the conversion of apigenin into acacetin, and these two genes are possibly responsible acacetin accumulation in disc florets and young leaves, respectively. Furthermore, combined analyses of ancestral chromosome reconstruction and phylogenetic trees revealed the distinct evolutionary fates of the two validated FOMT genes. Our study provides new insights into the biosynthetic pathway of flavonoid compounds in the Asteraceae family and offers a model for tracing the origin and evolutionary routes of single genes. These findings will facilitate in vitro biosynthetic production of flavonoid compounds through cellular and metabolic engineering and expedite molecular breeding of C. indicum cultivars. [ABSTRACT FROM AUTHOR]

It is well known that investigation on exact solutions of nonlinear fractional partial differential equations (PDEs) is a very difficult work compared with integer‐order nonlinear PDEs. In this paper, based on the separation method of semifixed variables and integral bifurcation method, a combinational method is proposed. By using this new method, a class of generalized time‐fractional thin‐film equations are studied. Under two kinds of definitions of fractional derivatives, exact solutions of two generalized time‐fractional thin‐film equations are investigated respectively. Different kinds of exact solutions are obtained and their dynamic properties are discussed. Compared to the results in the existing references, the types of solutions obtained in this paper are abundant and very different from those in the existing references. Investigation shows that the solutions of the model defined by Riemann–Liouville differential operator converge faster than those defined by Caputo differential operator. It is also found that the profiles of some solutions are very similar to solitons, but they are not true soliton solutions. In order to visually show the dynamic properties of these solutions, the profiles of some representative exact solutions are illustrated by 3D graphs. [ABSTRACT FROM AUTHOR]

Purpose: The genotype distribution of human papillomavirus (HPV) infection varies greatly in different regions. This study aims to determine the prevalence and type-specific distribution of HPV among females from Chengdu and Aba in Sichuan Province, which differ in geographical location, economic status, and living habits. These can serve as evidence of epidemic patterns for future design and implementation of vaccination and screening programs. Methods: A retrospective cross-sectional study was conducted on 144 113 women who underwent cervical screening at Chengdu Women's and Children's Central Hospital from January 2015 to September 2020. Meanwhile, 1799 samples from February 2018 to December 2021 were collected from Aba Maternal and Child Health Hospital. HPV DNA genotype testing was performed using real‐time PCR. The overall prevalence, annual trend, age-specific prevalence, and type distribution were analyzed. Results: The overall HPV prevalence was 22.51% in Chengdu. During 2015–2020, the highest prevalence rate was observed in 2018. Age-specific HPV distribution displayed a bimodal distribution among women aged ≤25 or ≥46 years old. The top three prevalent genotypes were HPV52, -16, and -58. Although the total prevalence of HPV in Aba was 14.23%, there was an upward trend from 2018 to 2021. However, no significant differences were identified in HPV infection rate across all age groups. HPV52, -53, and -16 were the major genotypes. Furthermore, single-type HPV infections and high-risk HPV infections were identified as the most common infection types in both regions. Conclusion: Our findings demonstrate the overall prevalence of HPV was still high in Chengdu and Aba. The age-specific prevalence distribution demonstrated different patterns. Non-vaccine-covered HR-HPV53, -51and LR-HPV81, -CP8304 were frequently detected, which was worth significant clinical attention. In summary, regional HPV screening provides valuable clinical guidance for cervical cancer prevention and vaccine selection in Western China. [ABSTRACT FROM AUTHOR]

Ecological sensitivity is the degree to which an ecosystem responds to external disturbances. Climate change and increasingly intensified human activities have individually or interactively influenced regional ecological sensitivity, which has in turn exposed the overall or regional population, resources, and environmental problems. Therefore, clarifying the impact of climate change and human activities on ecological sensitivity and making graded improvements are conducive to enhancing the resilience and sustainable development of the regional ecological environment. This study focused on 31 provinces in China and constructed a climate change, human activity, and ecological sensitivity indicator system based on meteorological, remote sensing, and statistical data from 2001 to 2020. Response surface methodology (RSM) was used to explore the impact of single factors and interactions between climate change and human activities on ecological sensitivity. Based on the composite sensitivity values that include ecological and climate sensitivity, this study divided the optimization zone, control zone, and governance zone and explored the improvement paths of the governance zone with high comprehensive sensitivity to climate and ecology. The results showed that: (1) The national ecological sensitivity value fluctuated and decreased over time, decreasing by 2.2% from 2001 to 2020. The overall spatial distribution showed a pattern of 'high in the west and low in the east, high in the north and low in the south.' The number of provinces with severe sensitivity and above continued to decrease, with a decrease of 7.1% in 2020 compared to 2001. (2) The main influencing factors varied in different regions. In terms of single factors, the proportion of provinces whose regional ecological sensitivity was affected by economic development, climate change, and population size was 77.4%, 67.7%, and 54.8%, respectively. In the analysis of interactions between economic development, climate change, and population size, the percentage of negative interaction effects was 69.6%, indicating that changes in one of most of the influencing factors had a reverse effect on the ecological sensitivity effect of another factor. (3) To reduce the negative impact of climate change on ecological sensitivity, it is necessary to coordinate economic development or population growth in a targeted manner to ensure sustainable economic and social development within the ecological carrying capacity of places with different natural conditions or development rates in the governance areas. [ABSTRACT FROM AUTHOR]

Polyene macrolactams are a special group of natural products with great diversity, unique structural features, and a wide range of biological activities. Herein, a cryptic gene cluster for the biosynthesis of putative macrolactams was disclosed from a sponge-associated bacterium, Streptomyces sp. DSS69, by genome mining. Cloning and heterologous expression of the whole biosynthetic gene cluster led to the discovery of weddellamycin, a polyene macrolactam bearing a 23/5/6 ring skeleton. A negative regulator, WdlO, and two positive regulators, WdlA and WdlB, involved in the regulation of weddellamycin production were unraveled. The fermentation titer of weddellamycin was significantly improved by overexpression of wdlA and wdlB and deletion of wdlO. Notably, weddellamycin showed remarkable antibacterial activity against various Gram-positive bacteria including MRSA, with MIC values of 0.10–0.83 μg/mL, and antifungal activity against Candida albicans, with an MIC value of 3.33 μg/mL. Weddellamycin also displayed cytotoxicity against several cancer cell lines, with IC50 values ranging from 2.07 to 11.50 µM. [ABSTRACT FROM AUTHOR]

Water resources are crucial for the development of ecosystems and humanity. The Yellow River Basin (YRB), as an important ecological area in China, is facing significant challenges in ecological protection and high-quality development due to global climate change and intense human activities. In order to alleviate the water resources crisis in the YRB, it is necessary to calculate the resilience of the water resources system and identify the main influencing factors. This paper considered the factors of water resources, social economy, and ecological environment, then constructed an evaluation framework of the water resources system resilience (WRSR) from three aspects: resistance, restoration, and adaptability. Taking nine provinces along the YRB as a case study, the WRSR was measured by using the entropy weight TOPSIS model, and its driving factors were analyzed with Geographical Detectors (GD). The results showed that: (1) From 2010 to 2022, the WRSR in the Yellow River Basin and various provinces was showing a fluctuating increasing trend, in which Ningxia had the highest average WRSR (0.646), while Shanxi had the lowest (0.168). (2) From three dimensions, the development trends of resistance, restoration, and adaptability in the YRB and various provinces from 2010 to 2022 were relatively stable. Shandong's resistance level far exceeded that of other provinces, having the highest average resistance value (0.692), and Ningxia had the highest average value of restoration (0.827) and adaptability (0.711). However, Gansu had the lowest average value of resistance (0.119), Sichuan had the lowest average value of restoration (0.097), and Shandong had the lowest average value of adaptability (0.110). (3) In terms of impact factors, the development and utilization rate of water resources (C13) and the development and utilization rate of surface water resources (C14) in the restoration subsystem consistently ranked in the top two of influencing factors. Similarly, the water consumption per 10,000 yuan of GDP (C26) in the adaptability subsystem consistently ranked within the top ten. On the other hand, the natural population growth rate (C6) in the resistance subsystem, as well as the impact of ammonia nitrogen emissions (C9) and total precipitation (C2) in wastewater, exhibited an upward trend. Based on these, this paper provides relevant suggestions for improving the WRSR in the YRB. [ABSTRACT FROM AUTHOR]