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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]

Aim: The widely observed positive response of productivity to biodiversity, known as the biodiversity‐productivity relationship (BPR), underpins nature‐based solutions for mitigating and adapting to global changes. Little is known of the role of such emergent processes in the restoration of damaged ecosystems. Here, we test for evidence of a BPR in degraded freshwater lakes, and its role in underpinning or undermining lake recovery from eutrophic states. Location: Lower Yangtze and Huaihe river basins, China, East Asia. Taxa: Freshwater phytoplankton; also macrophytes, fish, zooplankton and zoobenthos. Methods: A systematic review of biodiversity studies was conducted to enumerate freshwater biodiversity change during eutrophication, encompassing 572 samples from 155 lakes in East China. Empirical samples were then taken of 93 phytoplankton communities from 38 lakes in ecologically degraded states of eutrophication. Samples were analysed for niche overlap in relation to biodiversity and productivity, and metrics of network structure indicative of community stability. Results: Reviewed publications on eutrophication in East China lakes revealed losses in biodiversity of macrophytes, fishes, zooplankton and zoobenthos but not phytoplankton. Empirically sampled eutrophic lakes maintained high phytoplankton biodiversity through niche differentiation, and phytoplankton biodiversity correlated positively with biomass, in line with the expectations of BPR. Conclusions: The positive effect of biodiversity on phytoplankton productivity in eutrophic lakes acts in opposition to the negative impacts on productivity induced by eutrophication‐management strategies of nutrient suppression. In degraded systems, the BPR contributes to sustaining productivity of lake phytoplankton communities, impeding recovery from a eutrophic state. This is a case of the BPR playing an undesirable role at the ecosystem level. Lake recovery programmes need to anticipate that the control of phytoplankton biomass will depend on reducing nutrients to a level sufficient to degrade the internal structure of the phytoplankton community. [ABSTRACT FROM AUTHOR]

Dynamic urban growth is affected by various driving factors which are important for building cellular automata (CA) models. Two categories of urban‐growth drivers (i.e., proximity and accessibility) have not been well differentiated in simulating urban patterns. We built two CA models (Pro‐CAPSO and Acc‐CAPSO) using particle swarm optimization (PSO) incorporating the proximity and accessibility drivers and applied these models to simulate urban growth at Zhuji in China. The results show that although both models accurately reproduced urban growth from 2005 to 2015, differences in the allocation of urban cells are apparent. The proximity‐based model yielded a slightly better figure of merit (FOM) of 19.3% during calibration (2005–2010) as compared to the accessibility‐based model with FOM of 17.5%. An opposite trend (FOM 17.5% vs. 18.3%) was found for subsequent validation (2010–2015). The simulations by the Acc‐CAPSO model are closer to the real urban patterns as measured by landscape metrics. The results indicate that accessibility is a relatively robust driver in predicting long‐term future urban growth. For specific regions, urban future scenarios produced by the two models show opposing patterns; in the same areas, when Pro‐CAPSO predicted more new urban cells, Acc‐CAPSO predicted fewer, and vice versa. Our methods are useful for modelers in selecting appropriate factors between proximity and accessibility and arrange the combination to represent human disturbance when simulating urban growth. [ABSTRACT FROM AUTHOR]

Top‐down and bottom‐up controls regulate the structure and stability of ecosystems, but their relative roles in terrestrial systems have been debated. Here we studied a hydro‐inundated land‐bridge system in subtropical China and tested the relative importance of these two controls in determining the rodent‐mediated regeneration of a locally dominant tree species. Our results showed that both controls operated in terrestrial habitats and that their relative importance switched as habitat size changed. Habitat loss initially removed predators of rodents that released rodent populations and triggered massive seed predation (top‐down control), leading to reduced seedling establishment. A further reduction in habitat size led to decrease in rodent population that was supposed to increase seedling survival of the tree species, but the decline in habitat size deteriorated the abiotic environments (bottom‐up control) that severely prevented seedling recruitment. As the ongoing global land use change is creating increasing number of small‐sized forest fragments, our findings provide novel insights into the restoration of seriously fragmented forests. [ABSTRACT FROM AUTHOR]

Lake biodiversity is an incomplete indicator of exogenous forcing insofar as it ignores underlying deformations of community structure. Here, we seek a proxy for deformation in a network of diatom assemblages comprising 452 species in 273 lakes across China. We test predictions from network theory that nodes of similar type will tend to self‐organize in an unstressed system to a positively skewed frequency distribution of nodal degree. The empirical data reveal shifts in the frequency distributions of species associations across regions, from positive skew in lakes in west China with a history of low human impacts, to predominantly negative skew amongst lakes in highly disturbed regions in east China. Skew values relate strongly to nutrient loading from agricultural activity and urbanization, as measured by total phosphorus in lake water. Reconstructions through time show that positive skew reduces with temporal intensification of human impacts in the lake and surrounding catchments, and rises as lakes recover from disturbance. Our study illustrates how network parameters can track the loss of aquatic assemblage structure in lakes associated with human pressures. [ABSTRACT FROM AUTHOR]

Abstract: Background: Non‐diabetic renal disease (NDRD) has been widely known in diabetic patients. The clinical differentiation between diabetic nephropathy (DN) and NDRD is still not so clear and effective. Aim: To analyse the pathological characteristics and distribution of renal injury in selected type 2 diabetic patients. Comparison between DN and NDRD in clinical characteristics, to find important predictors for NDRD. Methods: To conduct retrospective analysis of clinical, laboratory and pathohistological data of type 2 diabetic patients in whom renal biopsies were performed from March 2010 to September 2014 in Shandong Provincial Hospital affiliated to Shandong University (n = 88). Results: According to the findings of renal biopsy, the incidences of DN, NDRD and DN complicated with NDRD were 20.46, 72.73 and 6.82% respectively. The most common NDRD found were: membranous nephropathy, followed by IgA nephropathy and focal segmental glomerulosclerosis. In multivariate logistic‐analysis, fasting blood glucose (odds ratio (OR) 0.714; 95% confidence interval (CI) = 0.543–0.939; P = 0.016) and absence of diabetic retinopathy (OR 18.602; 95% CI = 2.176–159.018; P = 0.003) were independent predictors of NDRD. Conclusions: This study confirmed a considerably high prevalence of NDRD in type 2 diabetic patients with renal injury. As some cases of NDRD are readily treatable or remittable, we should consider renal biopsy in selected diabetic patients with renal involvement, especially in those with effective blood glucose control and the absence of diabetic retinopathy. [ABSTRACT FROM AUTHOR]

This study investigates how humor usage (including positive and negative humor styles) influences employees' responses to the same stressful events, namely, the auto‐correlation between stress experiences at two time points. Moreover, it examines differences between Australian and Chinese employees in such effects via bicultural comparisons. Results from a two‐wave survey of 109 Australian and 141 Chinese employees indicated that humor usage moderated the StressTime1 – StressTime2 relationship for Australian employees but not for Chinese employees. Specifically, the positive relationship between the two stress measures became weaker for Australians who were higher in humor than those lower in humor. Similarly, Positive humor mitigated the relationship between StressTime1 and StressTime2 only for the Australians but not the Chinese. However, Negative humor exerted no influence on the focal relationship in either sample. Organizations should encourage employees to use humor in effective ways, thereby improving stress coping skills and reducing workplace stress. [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]

The article offers information on the research "Petrogenesis of Granite complex in the Jiudingshan porphyry Cu-Mo Deposit, Western Yunnan, China: Constraints from Geochronology, Geochemistry and Sr-Nd-Hf Isotopes" by Wang Rong and colleagues. Topics discussed include geochemical compositions of the rock, isotopic analysis of hafnium isotope zircon uranium-lead dating, and rock formation due to crust-mantle interaction.

Objectives: The proportion of older people with dementia in China is gradually increasing with the increase in the aging population over recent years. Hypertension and diabetes are common non‐communicable diseases among rural populations in China. However, it remains unclear whether these conditions affect the occurrence and development of cognitive impairment as there is limited research on cognitive status and its risk factors among residents of rural areas. Methods: A multi‐stage stratified cluster random sampling method was used to select 5400 participants from rural permanent residents. A self‐designed structured questionnaire was used to investigate demographic data of the participants. Cognitive function was assessed using the Montreal Cognitive Function Assessment Scale (MoCA). The results were analyzed using chi‐square test, ANOVA and multiple linear regression analysis. Results: A total of 5028 participants returned the survey, giving a response rate of 93.1%. Higher education (odds ratio (OR) = 3.2, 95% confidence interval (CI) 2.87–3.54, p < 0.001), higher income (OR = 1.61, 95% CI 1.16–2.07, p < 0.001), and dietary control (OR = 0.66, 95%CI 0.34–0.98, p < 0.001) were protective factors. A visual representation of the relationship between annual income and MoCA score showed an inverted U‐curve, the group with an annual income of 6000–7999 RMB had a maximum OR of 1.93 (95%CI 0.12–2.74, p < 0.001). While difficulty in maintaining sleep were risk factors for cognitive impairment (OR = −2.28, 95% CI–4.18–0.39, p = 0.018). Conclusions: Participants with middle incomes had better cognitive status than those with the highest incomes. Higher education, proper diet control and good sleep are beneficial to the cognitive status of residents in rural areas. Key points: Higher education level, higher income level and diet control are protective factors for the development of cognitive dysfunction.Cognitive dysfunction is more likely to occur in women and in people who have difficulty maintaining sleep.There were no significant differences in the demographic characteristics of patients with hypertension, diabetes, the combination of hypertension and diabetes, and healthy residents in low‐income rural areas.The cognitive status of middle‐income people is better than that of high‐income people than that of low‐income people, a visual representation of the relationship between annual income and MoCA score showed an inverted U‐curve. [ABSTRACT FROM AUTHOR]

Shidian is a recent meteorite which fell in Yunnan province, China, on November 27, 2017, and has been classified as a CM2 chondrite. Petrography, mineralogy, oxygen and chromium isotopic composition, reflectance spectrum, and density studies of Shidian are reported in this study. Clasts with different aqueous alteration degree, two type 1 clasts with nontypical CM petrography, and one metamorphic clast are observed in Shidian. Mineralogically, Shidian main body consists of phyllosilicates (∼70 vol%), forsterite (∼13 vol%), fayalitic olivine, carbonates, sulfide, high‐Ca pyroxene, magnetite framboids, and Fe‐Ni metal. The average electron microprobe analysis (EMPA) analytical totals of phyllosilicates are 84.07 ± 1.75 wt%, with average FeO/SiO2 of tochilinite–cronstedtite intergrowths (TCIs) in different clasts ranging from 1.18 to 3.29. The bulk geochemical composition is characterized by flat rare earth element pattern, and by depletion of highly volatile elements. The whole rock oxygen isotopic composition is −0.51 ± 0.73‰, 5.44 ± 1.01‰, and −3.38 ± 0.20‰ for δ17O, δ18O, and Δ17O, respectively, with bulk chromium isotopic composition as ε54Cr = 1.00 ± 0.11. The grain density, bulk density, and porosity are 2.758 ± 0.008 g cm−3, 2.500 ± 0.004 g cm−3, and 9.37 ± 0.59%, respectively. The reflectance spectrum shows "blue" (negative) continuum slope across the visible and near‐infrared range, with characteristic absorption features (such as 0.765, 0.923, and 1.160 μm for phyllosilicates). These characteristics indicate that Shidian is an unheated, brecciated CM chondrite and may be an analog of asteroid Bennu. [ABSTRACT FROM AUTHOR]

Foliar stable nitrogen (N) isotopes (δ15N) generally reflect N availability to plants and have been used to infer about changes thereof. However, previous studies of temporal trends in foliar δ15N have ignored the influence of confounding factors, leading to uncertainties on its indication to N availability. In this study, we measured foliar δ15N of 1811 herbarium specimens from 12 plant species collected in southern China forests from 1920 to 2010. We explored how changes in atmospheric CO2, N deposition and global warming have affected foliar δ15N and N concentrations ([N]) and identified whether N availability decreased in southern China. Across all species, foliar δ15N significantly decreased by 0.82‰ over the study period. However, foliar [N] did not decrease significantly, implying N homeostasis in forest trees in the region. The spatiotemporal patterns of foliar δ15N were explained by mean annual temperature (MAT), atmospheric CO2 (PCO2), atmospheric N deposition, and foliar [N]. The spatiotemporal trends of foliar [N] were explained by MAT, temperature seasonality, PCO2, and N deposition. N deposition within the rates from 5.3 to 12.6 kg N ha−1 year−1 substantially contributed to the temporal decline in foliar δ15N. The decline in foliar δ15N was not accompanied by changes in foliar [N] and therefore does not necessarily reflect a decline in N availability. This is important to understand changes in N availability, which is essential to validate and parameterize biogeochemical cycles of N. [ABSTRACT FROM AUTHOR]

Both paleoclimatic change and anthropogenic habitat destruction can have adverse effects on species demography and, in turn, could lead a species towards being endangered and rare. Understanding the relative importance of these natural and anthropogenic factors driving species endangerment and rarity is thus crucial for effective conservation planning but remains elusive. Here, we examine the phylogeography and demographic history of an endangered conifer species in China, Torreya jackii Chun, and assess the relative importance of natural and anthropogenic factors that might have put the species in its endangered state. We collected tissue samples from all the 13 extant wild populations, and analyzed the genetic variation using eight nuclear microsatellites and four chloroplast and one mitochondrial DNA fragments. We found low genetic and nucleotide diversities, which could explain the absence of spatial and phylogeographic structure. Using a hierarchical approximate Bayesian computation technique, we identified the demographic scenario that best fits the genetic data and found that effective population size was low at least 200 000 years ago but expanded after the last glacial maximum (LGM). The paleoclimatic niche model revealed a profound effect of precipitation on the distribution of T. jackii and predicted that the current distribution areas were suitable during the LGM. Despite the post‐LGM expansion, the best‐supported scenario showed a dramatic population collapse during the past 300 years, when anthropogenic disturbances also increased dramatically. Overall, our study sheds light on how historical factors and human impacts jointly threaten the persistence of a species, and these aspects should be duly considered in species conservation planning. [ABSTRACT FROM AUTHOR]

The photometric properties of the uppermost lunar regolith are used in the spectroscopic study. China's Chang'E‐5 (CE‐5) mission successfully landed in the Northern Oceanus Procellarum of the Moon, carrying the scientific payload lunar mineralogical spectrometer (LMS). LMS performed full‐view scanning and obtained the reflectance spectra in various geometric configurations. The photometric properties, including the single‐scattering albedo ω and two parameters of the Henyey‐Greenstein phase function (b, c), were derived. Our modeling results showed weak backward scattering and strong forward scattering properties of the regolith at the CE‐5 landing site. Meanwhile, the asymmetry parameter (−b×c) $(-b\times c)$ indicates that CE‐5 regolith has weaker forward scattering than the Apollo lunar soil samples and the regolith at the Chang'E‐4 landing site. The derived Hapke parameters can be used for comparison with that of the returned lunar sample, supporting further studies of lunar spectroscopy, and can be the ground truth of the CE‐5 landing area. Plain Language Summary: The in‐situ mineral compositions of the lunar regolith can be retrieved using spectral observations with known photometric properties of the lunar surface. The lunar mineralogical spectrometer installed on the Chang'E‐5 lander conducted in‐situ full‐view scanning, and obtained many spectral data. We derived a photometric function using these data to study the properties of the regolith. These findings can be compared to the measured value of the lunar returned samples of CE‐5 to support future spectroscopy research and provide a better understanding of the mineralogical information at the CE‐5 landing area. Key Points: The photometric properties of the lunar regolith are revealed by in‐situ spectrum data from the Chang'E‐5 Lunar Mineralogical SpectrometerThe derived photometric parameters contribute to a better understanding of the properties of the regolith on the near side of the moonThe forward scattering was dominant in the landing site, consistent with the compositions of the lunar samples returned from the Chang'E‐5 [ABSTRACT FROM AUTHOR]

Dispersal that unites spatially subdivided populations into a metapopulation with source–sink dynamics is crucial for species persistence in fragmented landscapes. Understanding such dynamics for pollinators is particularly urgent owing to the ongoing global pollination crisis. Here, we investigated the population structure and source–sink dynamics of a pollinating wasp (Wiebesia sp. 3) of Ficus pumila in the Zhoushan Archipelago of China. We found significant asymmetry in the pairwise migrant numbers for 22 of 28 cases on the historical timescale, but only two on the contemporary timescale. Despite a small population size, the sole island not colonized by a superior competitor wasp (Wiebesia sp. 1) consistently behaved as a net exporter of migrants, supplying large sinks. Comparable levels of genetic diversity, with few private alleles and low genetic differentiation (total Fst: 0.03; pairwise Fst: 0.0005–0.0791), were revealed among all the islands. There was a significant isolation‐by‐distance pattern caused mainly by migration between the competition‐free island and other islands, otherwise the pattern was negligible. The clustering analysis failed to detect multiple gene pools for the whole region. Thus, the sinks were most probably organized into a patchy population. Moreover, the estimates of effective population sizes were comparable between the two timescales. Thus the source–sink dynamics embedded within a well‐connected population network may allow Wiebesia sp. 3 to persist at a competitive disadvantage. This study provides evidence that metapopulations in the real world may be complicated and changeable over time, highlighting the necessity to study such metapopulations in detail. [ABSTRACT FROM AUTHOR]

Host specificity of phytophagous insects plays a critical role in the maintenance of plant diversity. However, a lack of approaches to identify the larvae of phytophagous insects, which usually have similar morphology, can lead to misinterpretation of their host ranges.Acorn weevils are seed‐exploiting parasites of Fagaceae species, a dominant plant group in subtropical evergreen broad‐leaved forests (EBLFs). Therefore, variation in their host specificity may profoundly influence plant diversity in this ecosystem.Here, we collected larvae of acorn weevils from 36 655 seeds of Fagaceae species in EBLFs in southeastern China and performed multiple operational taxonomic unit (OTU) delimitation analyses using one mitochondrial (COI) and two nuclear (ArgK and EF1‐α) genes to reveal species composition of acorn weevils and assess the variation in host specificity among OTUs.We analysed the DNA barcoding sequences from 478 larvae and 4 adults of acorn weevils sampled from 17 common Fagaceae species (five genera) and detected 11 OTUs. Moreover, host range varied drastically among different OTUs, with Curculio bimaculatus being the most generalised.Our results revealed high diversity of acorn weevils and that strong variation in host specificity can even exist among OTUs in the same genus, addressing the need to distinguish different Curculio species before conducting forest management in EBLFs. [ABSTRACT FROM AUTHOR]

Objective: The purpose of the present study was to evaluate the present situation and risk factors for the misdiagnosis of osteonecrosis of femoral head (ONFH), providing the basis for accurate diagnosis of ONFH. Methods: For this retrospective study, 1471 patients with ONFH were selected from the China Osteonecrosis of Femoral Head Database (CONFHD). These patients had been recruited between July 2016 and December 2018. According to whether or not they were misdiagnosed, the patients were divided into two groups, with 1168 cases (22–84 years old) included in the diagnosis group and 303 cases (21–80 years old) in the misdiagnosis group. Misdiagnosis was measured using the following criteria: (i) the patient had the same symptoms and signs, and the second diagnosis was not consistent with the initial diagnosis within 6 months; and (ii) the patient was admitted to a hospital participating in CONFHD and the previous diagnosis was inconsistent with the diagnosis given by the expert group. Comparisons of age, visual analogue scale for pain, and body mass index between the two groups were performed using a t‐test. Gender, causes of ONFH, primary diseases requiring corticosteroids, methods of corticosteroid use, corticosteroid species, type of trauma, onset side of the disease, pain side, whether symptoms are hidden, and type of imaging examination at the initial visit were compared using the χ2‐test. Years of alcohol consumption, weekly alcohol consumption, and physician title at the initial visit were compared using a Mann–Whitney U‐test. Furthermore, the statistically significant factors were evaluated using multiple regression analysis to investigate the risk factors of misdiagnosis. Results: A total of 303 patients (20.6%) were misdiagnosed: 118 cases were misdiagnosed as lumbar disc herniation, 86 cases as hip synovitis, 48 cases as hip osteoarthritis, 32 cases as rheumatoid arthritis, 11 cases as piriformis syndrome, 5 cases as sciatica, and 3 cases as soft‐tissue injury. Whether symptoms are hidden (P = 0.038, odds ratio [OR] = 1.546, 95% confidence interval [CI] = 1.025–2.332), physician title at the initial visit (P < 0.001, OR = 3.324, 95% CI = 1.850–5.972), X‐ray examination (P < 0.001, OR = 4.742, 95% CI = 3.159–7.118), corticosteroids (P < 0.001, OR = 0.295, 95% CI = 0.163–0.534), alcohol (P < 0.001, OR = 0.305, 95% CI = 0.171–0.546), and magnetic resonance imaging (MRI) examination (P = 0.042, OR = 0.649, 95% CI = 0.427–0.985) were each found to be associated with misdiagnosis. Conclusion: Osteonecrosis of the femoral head is easily misdiagnosed as lumbar disc herniation, hip synovitis, hip osteoarthritis, and rheumatoid arthritis. Patient history of corticosteroid use or alcohol abuse and MRI examination at the initial diagnosis may be protective factors for misdiagnosis. Hidden symptoms, physician title at the initial visit (as attending doctor or resident doctor), and only X‐ray examination at the initial diagnosis may be risk factors for misdiagnosis. [ABSTRACT FROM AUTHOR]