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To understand the fish community structure characteristics and changes in Poyang Lake after the Yangtze River fishing ban in 2021, seven sampling stations were established, namely in Hukou, Lushan, Duchang, Yongxiu, Nanjishan, Ruihong, and Poyang, for fishery resource surveys between 2020 and 2021. The results showed that 93 fish species were identified, belonging to 11 orders, 20 families, and 61 genera, which was an increase of 4.5% from before the fishing ban. Of these, 52 Cyprinidae species were identified, comprising the highest proportion (55.91%). Four invasive alien species (hybrid sturgeon, Cirrhina mrigala, Piaractus brachypomus, and Mugil cephalus) were identified, and the number of alien species in Poyang Lake was higher than before the fishing ban. Carnivorous and mid-lower-level fish showed a significant increase, accounting for 47.31% and 38.71% of the total species, respectively. Compared with the Yangtze River before the fishing ban, the body length and body weight of the main economic fish in Poyang Lake increased by 6.10–61.26% and by 15.14–291.57%, respectively. In terms of age structure, the proportion of major economically important fish aged 1 or 2 years decreased significantly, while the proportion of older fish increased substantially. There was little difference in the diversity of fish communities at different stations in Poyang Lake. In terms of biodiversity, the Shannon–Wiener index ranged from 2.158 to 2.909, with Poyang having the highest value and Nanjishan the lowest. Margalef's index ranged from 4.265 to 6.459, with Lushan having the highest value and Nanjishan the lowest. Pielou's index ranged from 0.617 to 0.822, with Duchang having the highest value and Nanjishan the lowest. Hence, the Yangtze river fishing ban has played an important and positive role in the restoration of fishery resources in Poyang Lake. However, long-term tracking and monitoring are needed to provide information to comprehensively evaluate the ecological impact of the Poyang Lake fishing ban. [ABSTRACT FROM AUTHOR]

Polymers play a crucial role in promoting the progress of high‐performance inverted perovskite solar cells (PSCs). However, few polymers have simultaneously achieved defect passivation and device encapsulation in PSCs. Herein, a telechelic silicone polymer (poly(dimethylsiloxane‐co‐methylsiloxane acrylate) [PDMA]) is introduced, which possesses crosslinking capability to enable structure regulation through a condensation reaction. By leveraging the advantages of the polymers before and after crosslinking, a synergistic strategy of defect healing and device encapsulation for PSCs is developed via the application of the targeted polymer. PDMA as additives anchors tightly at the grain boundaries (GBs) and bridges the perovskite grains, achieving defect passivation and GBs crosslinking, increasing the efficiency of inverted PSCs from 22.32% to 24.41%. Crosslinked PDMA (CPDMA) is used as an encapsulant to encapsulate the entire device, enabling non‐destructive encapsulation at room temperature and inhibiting perovskite degradation under photothermal aging. Remarkably, the PDMA‐modified device with CPDMA encapsulation maintains 98% of its initial efficiency after 1200 h under continuous illumination at 55 ± 5 °C and retains 95% of its original efficiency after 1000 h of damp heat testing, meeting one of the IEC61215:2016 standards. [ABSTRACT FROM AUTHOR]

Simple Summary: The objective of this study was to investigate the correlation between juvenile Acipenser sinensis density and the eDNA content in a controlled laboratory aquarium environment. The results obtained from fluorescent quantitative PCR indicated an overall increasing trend in the eDNA content, which tended to stabilize after three days. Furthermore, a significant positive linear correlation was observed between the density of juvenile A. sinensis and eDNA content at different time points (R2 = 0.768~0.986). When the juvenile A. sinensis were removed at a density of 0.114 ind./L, there was a negative correlation between eDNA content and time. Based on AIC and BIC analyses, a power function model was employed to illustrate the degradation relationship between eDNA content and time. Since the construction of the Gezhouba Dam, Chinese sturgeon (Acipenser sinensis) numbers have gradually declined, rendering this species critically endangered according to the International Union for the Conservation of Nature. Environmental DNA (eDNA) technology plays an important role in monitoring the abundance of aquatic organisms. Species density and biomass have been proven to be estimable by researchers, but the level of accuracy depends on the specific species and ecosystem. In this study, juvenile A. sinensis, an endangered fish, were selected as the research target. Under controlled laboratory conditions in an aquarium, one, two, four, six, and eight juvenile A. sinensis were cultured in five fish tanks, respectively. Water samples were filtered at eight different time points for eDNA content analysis. Additionally, eDNA yield was tested at six different time points after a 0.114 ind./L density of A. sinensis was removed, and the employed degradation model was screened using the Akaike information criterion (AIC) and the Bayesian information criterion (BIC). The results showed that eDNA content remained stable after 3 days and exhibited a significant positive linear correlation with the density of A. sinensis (R2 = 0.768~0.986). Furthermore, eDNA content was negatively correlated with the 3-day period after the removal of A. sinensis. The power function had the smallest AIC and BIC values, indicating better fitting performance. This study lays a momentous foundation for the application of eDNA for monitoring juvenile A. sinensis in the Yangtze Estuary and reveals the applicability of eDNA as a useful tool for assessing fish density/biomass in natural environments. [ABSTRACT FROM AUTHOR]