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Aim: Over the last century, lakes all over the world have experienced significant eutrophication and become more susceptible to critical transitions. This has prompted a growing need to understand how community dynamics shift following ecological perturbations. This study aims to elucidate the present status, spatial patterns and determinants of biological diversity, and how they have changed in response to alterations driven by eutrophication. Location: Lakes of East China, mostly in the Yangtze River Basin. Taxa: Bacillariophyceae (163 species in 33 genres, see taxa names in Appendix S1). Methods: The environmental conditions of over 60 lakes were assessed based on parameters such as water quality, physical characteristics and biogeochemical constituents. Surface sediment samples and high‐resolution sediment records were collected to quantify the biodiversity of diatom communities, and principal component analysis (PCA) was used to determine the major environmental gradients. Meanwhile, linear regression, canonical correlation analysis and Mantel tests were used to quantify the correlations between variables. Results: Biodiversity metrics showed no distinct geographic patterns, although areas near large lakes showed comparatively high evenness. Smaller pairwise dissimilarities were observed among hypereutrophic lakes in comparison to lakes with a lower trophic status. The past century has witnessed a decrease in both pairwise dissimilarity and the standard deviation of evenness. A significant statistical association was found between dissimilarity and ionic concentration and composition in the surface sediment of lakes, rather than nutrient levels. Main Conclusions: Following regional eutrophication and human disturbance, a significant reduction in biodiversity differentiation was observed in lakes located in East China. Currently, the dominant factor in determining the beta diversity of diatom communities is geochemical conditions rather than nutrient concentrations. Long‐term stress caused by cultural eutrophication may also have altered the dominant determinant of regional biodiversity and diatom community dynamics. [ABSTRACT FROM AUTHOR]

The extremal spatial dependence of significant wave height (H S) in the South China Sea (SCS) is discussed by combining altimeter observations of ocean satellites and ERA5 reanalysis dataset from the period 2011–2023. A spatial conditional extremes (SCE) model allowing different classes of extremal dependence is established, which uses a reliable Markov chain Monte Carlo (MCMC) scheme to realize the parameter inference. In this work, four transects are selected in the northern South China Sea (NSCS) and the central South China Sea (CSCS) respectively, which are approximately southwest-northeast (SW-NE) and northwest-southeast (NW-SE), and the H S data is transformed to the standard Laplace scale. The model fitting results show that the extremal dependence characteristics of different regions and directions in the SCS are different. The mean dependence of H S in NSCS decays faster than in CSCS, and the mean dependence on NW-SE transects decays faster than SW-NE transects. In general, the SW-NE transect in CSCS is observed a longer-range extremal dependence, which is potentially related to the storm direction in the SCS. • Simultaneous events of extreme oceans at multiple locations often have greater risks. • Important to analyze the spatial dependence of extreme wave height. • Satellite altimeter (HY-2) and ERA5 reanalysis dataset incorporated. • Spatial conditional extremes model used to quantify extremal spatial dependence of the effective wave heights for four transects in the South China Sea. • Extreme wave height shows greater extremal dependence from southwest to northeast than from northwest to southeast in the central South China Sea. [ABSTRACT FROM AUTHOR]

The pharmacokinetic (PK) characteristics of drugs were altered under high‐altitude hypoxia. We aim to describe the population PK of atorvastatin (ATV) to identify patient characteristics that are predictive of variability in the PK parameters of the ATV and investigate the effects of high‐altitude hypoxia on the blood concentration of ATV in patients with hyperlipidemia. A total of 160 plasma concentrations were collected from 40 patients with hyperlipidemia in plateau areas and 40 in plain areas. The population pharmacokinetic model of patients with hyperlipidemia in plateau and plain areas of China was established by a nonlinear mixed‐effects model. The PK of ATV were described by a 1‐compartment model with first‐order elimination. The main PK parameters of ATV were the first‐order absorption rate (0.76 hour−1 fixed); clearance (174.22 L/h) and apparent volume of distribution (1119.62 L). The values of area and age were identified as significant covariates for the clearance, area, age, and urea for the volume of distribution. The steady‐state peak concentration in the plateau area was higher than that in the plain area. This study may suggest dose reduction is necessary for patients with hyperlipidemia in high altitudes. [ABSTRACT FROM AUTHOR]

This investigation delves into the utilization of tremolite, a rare mineral, as a pottery temper for cooking vessels of the late Neolithic lower Yangtze Liangzhu culture. Raman spectroscopy analysis of 165 mineral-tempered pottery sherds from the Dazemiao site revealed that tremolite was the predominant tempering material for tripods (ding), whereas a mixture of feldspar and quartz was used for open-topped vats (da-kou-gang). SEM images indicate that the tremolite temper exhibits relatively coarse fiber structure, corresponding to one of the nephrite materials used for the Liangzhu jade. It is suggested that the Liangzhu miners reallocated materials according to nephrite quality, formulating different product lines, including different types of jade objects and pottery temper. Additionally, the utilization of tremolite temper persisted throughout the entire Liangzhu culture. The presence of tremolite-tempered pottery in regions without indigenous tremolite mines necessitated robust logistical networks for the transportation of these bulky materials. The tremolite temper not only reconfirms the strong 'jade culture' of Liangzhu, but also provides evidence of extensive socio-economic exchanges between different geographical regions on the Yangtze River delta. • Potters used tremolite temper in Liangzhu culture (5300-4300 BP), China. • Tremolite temper was widely used in the cooking vessel – tripod (Ding). • Nephrite jade craftsmanship influenced the use of tremolite temper. • A riverine logistical network encouraged the circulation of tremolite. • A complex polity made efforts to integrate transport networks. [ABSTRACT FROM AUTHOR]