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In order to explore the desilting effects of different channel desilting schemes, a hydrodynamic model accelerated by a graphic process unit (GPU) was used to construct a flood evolution model for the study area and simulate the flood inundation situation of the channels in the study area after implementing four desilting schemes at different return periods. The results show that: ① The schemes in terms of flood inundation alleviation and desilting excavation volume in descending order are as follows: full-section scheme, combination scheme, only floodplain scheme, and only thalweg scheme. ② The inundated area of each scheme decreases by 4.20%–21.68%, 1.57%–13.85%, 6.66%–43.6%, and 5.63%–39.7%, respectively. In terms of inundated area reduction rate, the combination scheme has an average reduction of 2.19% compared with the full-section scheme at different return periods, but the excavation volume of the full-section scheme is 21.89% higher than that of the combination scheme. ③ The ratio of the inundated area reduction rate to the excavation volume is used to represent the ability to reduce the inundated area per unit excavation volume. The ability of each desilting scheme to reduce inundated area is 7.34%–12.49%, 2.75%–7.98%, 8.86%–19.08%, and 9.13%–21.18%, respectively. The combination scheme has the strongest ability to reduce the inundated area at different return periods. Therefore, the combination scheme is determined as the comprehensive optimal scheme among the four desilting schemes. This study can provide a reference for channel desilting, flood control, and disaster reduction.

Zooplankton, as an important component of mountain river ecosystems, play a crucial role in the cycling of matter and the flow of energy. However, the depth and systematic research on the formation mechanisms and influencing factors of zooplankton communities in mountain streams are poorly understood. Here, we conducted field sampling and investigated the spatiotemporal distribution of the zooplankton community structure and the major environmental factors in mountain streams to explore the principles underlying their effects on the zooplankton community. The results showed that zooplankton community structure exhibited significant seasonal variations. Rotifera and Cladocera were the dominant groups, with Rotifera dominant in warm weather and Cladocera dominant in February. The analysis revealed that temperature and trace elements are the main factors affecting zooplankton diversity. Our model explained 46.50% of the variation in zooplankton through temperature, water properties, nutrients, and trace elements. The results highlighted that temperature acted directly on the zooplankton community and also exhibited indirect and negative effects on zooplankton diversities through altering trace elements. Trace element variables had a significant impact on zooplankton community distribution. Our study systematically quantified these relationships, providing insights into the ecological processes of mountain streams and offering a scientific basis for the ecological protection of mountain streams.

Minor and trace elements in soil play a crucial role in regulating ecological processes that sustain the functionality of forest ecosystems. In this study, we have selected three conifer forests (Pinus sylvestris, Picea asperata, Larix principis-rupprechtii), one broadleaf forest (Betula Platyfilla) and one mixed forest of Betula Platyfilla and Larix principis-rupprechtii in the Winter Olympic core area and determined the pattern of 12 typical elements (B, Fe, V, Cr, Ni, Co, Mn, As, Cu, Zn, Sn and Se) in soils and their main drivers in the three different soil layers (A, B and C horizon) in each soil profile. Our results showed that the concentrations of B, Fe, Cr, Cu, Ni and Sn were mainly enriched in the broadleaf forest and mixed broadleaf–conifer forest zones, and the average concentrations of Co, Mn, V, Zn, As and Se were mainly enriched in coniferous forest zones in contrast. We have observed that the mean concentrations of Fe, Cr, Ni, Zn, As, Sn and Co increase with soil depth in the BP forest. The concentrations of Se and Cu were higher in the A layer than the C layer. The piecewise structural equation modeling (piecewiseSEM) results visualized a direct and negative effect on B, Fe, V, Cr and Ni concentrations due to soil temperature, while the concentrations of Se is mainly influenced by soil temperature and soil properties.

Background: Asian schistosomiasis is projected to be eliminated by 2030 according to World Health Organization road map for neglected tropical diseases 2021–2030. Snail control is an important measure but has not yet been systematically evaluated at a country scale. Here, we report the findings from a nationwide survey to demonstrate the dynamics of Oncomelania and its potential role in transmission interruption of schistisomiasis in the People's Republic of China (P.R. China). Methods: Between March 2016 and December 2017, we conducted a nationwide census on Oncomelania snail habitats in P.R. China. All historically recorded snail habitats were identified and reviewed. Information on habitat attributes, including the infestation of snails, was collected. The shape of habitats was determined using global positioning system and geographical information system technologies. The relationship between snail control and schistosomiasis elimination was established in 378 endemic counties. The comparison of accumulated snail-infested range (ASR) and the median ratio of eliminated ASR between the transmission-interrupted and endemic counties was tested by a non-parametric test (Mann–Whitney) with a significance level of 0.05. Results: Overall, 15,377.7 million m2 of potential snail habitats with a total of 356,550 snail habitats were identified in P.R. China. The ASR amounted to 86.0% of the total area. Most of the ASR (94.9%) and habitats (68.5%) were distributed in the middle and lower reaches of the Yangtze River. Snail habitats were found up to an altitude of 2859 m above the mean sea level. By 2017, 85.1% of habitats (73.0% of the ASR) had been eliminated with almost half of them eliminated between 1965 and 1982. The elimination of snail habitats promoted transmission interruption of schistosomiasis, but showed variable patterns in different landscapes. The ratio of eliminated ASR was 99.6 and 91.4% in water network and hilly areas, respectively, while it was only 64.8% in marshland areas, particularly in Hunan and Jiangxi where the two largest freshwater lakes of P.R. China are located. Marshland habitats were seen as the most difficult for transmission interruption, which calls for additional control measures in these settings. Conclusions: Our results support recent recommendations by the World Health Organization to implement snail control and demonstrate that schistosomiasis elimination can be achieved. The nationwide, high-resolution map of Oncomelania snail habitats in P.R. China will support further efforts to eliminate schistosomiasis. [ABSTRACT FROM AUTHOR]

Chinese hamster ovary (CHO) cells are commonly used to produce recombinant therapeutic proteins (RTPs). The yield of RTPs in CHO cells has been greatly improved through cell editing and optimization of culture media, cell culture processes, and expression vectors. However, the heterogeneity of cell clones and product aggregation considerably affect the yield and quality of RTPs. Recently, novel technologies such as semi-targeted and site-specific transgene integration, endoplasmic reticulum-residents, and cell culture process optimization have been used to address these issues. In this review, novel developments in the field of CHO cell expression system heterogeneity are summarized. Moreover, the advantages and limitations of the new strategies are discussed, and important methods for the control of RTP quality are outlined. [ABSTRACT FROM AUTHOR]