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The Vaganov–Shashkin process-based model was used to explore the variation characteristic of the radial growth rate of Pinus tabulaeformis in the agro-pastoral transition zone in northern China. The tree-ring width chronologies of the four sampling sites were significantly positively correlated with the simulated series (p < 0.01), and the simulated onset and end dates of tree radial growth indicated that April to October was the main growing season. Temperature affects the radial growth rate of tree stems at the start and end of the growing season, while soil moisture availability affects the radial growth rate in the main growing season. Despite the differences in amplitude, the integral growth rate showed a bimodal pattern, which to some extent responded to the hydrothermal configuration of the East Asian summer monsoon climate. Compared with the peak changes in the summer monsoon fringe area in Northwest China, the highest peak of the integral growth rate in this study area appeared around August in the late growing season, reflecting the adaptability of trees to the local climatic environment. The average values of the integral growth rate and rate due to soil moisture, inferred from extreme wide-ring and narrow-ring years, were significantly different (p < 0.01), while the average growth rates due to temperature were not significant (p > 0.05). The analysis results indicate that moisture availability is a key limiting factor for the radial growth of Pinus tabulaeformis. Our study provides valuable knowledge about the growth processes of the main tree species related to the hydroclimatic variables in northern China and offers a new perspective on mitigating the adverse effects of a warmer climate on the forest in the semi-arid region in the future. [ABSTRACT FROM AUTHOR]

Cimicifuga dahurica (C. dahurica) is an important medicinal plant in the northern region of China. The best supplemental light environment helps plant growth, development, and metabolism. In this study, we used two-year-old seedlings as experimental materials. The white light as the control (CK). The different ratios of red (R) and blue (B) combined light were supplemented (T1, 2R: 1B, 255.37 μmol m−2·s−1; T2, 3R: 1B, 279.69 μmol m−2·s−1; T3, 7R: 1B, 211.16 μmol m−2·s−1). The growth characteristics, photosynthetic pigment content, photosynthesis and chlorophyll fluorescence parameters, and primary metabolite content were studied in seedlings. The results showed that: 1) The fresh weight from shoot, root, and total fresh weight were significantly (P < 0.05) increased under T2 and T3 treatment. 2) The contents of chlorophyll a (Chl a) , chlorophyll b (Chl b), and total chlorophyll (Chl) were significantly (P < 0.05) increased under T2 treatment, and carotenoid (car) content was reduced. 3) The photochemical quenching (qP), the actual photosynthetic efficiency of PSII (Y(II)), and the photosynthetic electron transfer rate (ETR) from leaves were significantly (P < 0.05) increased under T1 treatment. The Net photosynthetic rate (Pn), stomatal conductance (Gs), intercellular CO 2 concentration (Ci), and transpiration rate (Tr) were significantly (P < 0.05) increased under T2 and T3 treatments. 4) A total of 52 primary metabolites were detected in C. dahurica leaves. Compared with CK, 14, 15, and 18 differential metabolites were screened under T1, T2, and T3 treatments. In addition, D-xylose, D-glucose, glycerol, glycolic acid, and succinic acid were significantly (P < 0.05) accumulated under the T2 treatment, which could regulate the TCA cycle metabolism pathway. The correlation analysis suggested that plant growth was promoted by regulating the change of D-mannose content in galactinol metabolism and amino sugar and nucleotide sugar metabolism. In summary, the growth of C. dahurica was improved under T2 treatment. • The growth of C. dahurica was improved under supplemental light with a ratio of red and blue light of 3:1. • Glycolysis and the TCA cycle play crucial roles in promoting C. dahurica growth. • D-mannose as a key differential metabolite, providing energy through respiration for C. dahurica growth. [ABSTRACT FROM AUTHOR]

The rainfall outputs from the latest convectionscale Weather Research and Forecasting (WRF) model are shown to provide an effective means of extending prediction lead times in flood forecasting. In this study, the performance of the WRF model in simulating a regional sub-daily extreme rainfall event centred over Beijing, China is evaluated at high temporal (sub-daily) and spatial (convectiveresolving) scales using different domain configurations and spin-up times. Seven objective verification metrics that are calculated against the gridded ground observations and the ERA-Interim reanalysis are analysed jointly using subjective verification methods to identify the likely best WRF configurations. The rainfall simulations are found to be highly sensitive to the choice of domain size and spin-up time at the convective scale. A model run covering northern China with a 1 : 5 : 5 horizontal downscaling ratio (1.62 km), 57 vertical layers (less than 0.5 km), and a 60 h spin-up time exhibits the best performance in terms of the accuracy of rainfall intensity and the spatial correlation coefficient (R'). A comparison of the optimal run and the initial run performed using the most common settings reveals clear improvements in the verification metrics. Specifically, R0 increases from 0.226 to 0.67, the relative error of the maximum precipitation at a point rises from -56 to-117%, and the root mean squared error decreases by 33.65 %. In summary, re-evaluation of the domain configuration options and spin-up times used in WRF is crucial for improving the accuracy and reliability of rainfall outputs used in applications related to regional sub-daily heavy rainfall (SDHR). [ABSTRACT FROM AUTHOR]

Contaminant concentrations often presented left censorship that below the limit of detection (LOD), which may contain true zero values because of no residue. In this study, we analyzed the concentrations of lead (Pb), cadmium (Cd), mercury (Hg), arsenic (As), and chromium (Cr) in 391 crayfish samples collected from 24 provinces of China, modelled the concentrations with two different models in a Bayesian framework, and evaluated health risk by estimating the target hazard quotient (THQ). The highest concentration was associated with Cr in Northwest China (0.1753 ± 0.1520 mg/kg w. w.), and the minimum concentration was Cd in Southwest China (0.0052 ± 0.0144 mg/kg w. w.), all heavy metal concentrations were below their safety limits. The posterior means of not detect rates P 0 of Pb, Cd, Hg, As, and Cr obtained with two models were both nearly equal to the observed not detect rates (51.15%, 36.83%, 27.37%, 64.71%, and 43.73%, respectively). The posterior probabilistic density lines for Pb, Hg, and Cd concentrations obtained with two models were similar, and fitted the empirical distributions well. The posterior density lines of THQs showed that the non–carcinogenic risk of As and Hg were significant high. Moreover, Bayesian approach presented a better understanding of the percentage of population exposed to potential risk. [Display omitted] • Bayesian approach with two different mixture models was used to evaluate health risk. • As and Hg posed significant health risk to consumers according to Bayesian approach. • Censored log–normal model described health risk of As more appropriately. • Probabilities of THQ for Hg and As exceeding 1 were more than for other metals. [ABSTRACT FROM AUTHOR]

Air-supported membrane structures are being widely used for coal-sheds or the enclosed buildings of stockyards. With the emergence of new functional requirements for buildings, the demand for an increase in both the span and size of air-supported membrane structures has been rapidly increasing in China. Till now, the largest span and length of structures in China have reached 200 m and 1300 m respectively. For air-supported membrane structures, the load-bearing capacity comes from the difference in air pressure between the interior and exterior, which causes the structure to be sensitive to wind and snow loads. This paper studies the wind-induced response of a constructed air-supported membrane structure for a coal-shed cover building with a span of 115 m and width of 317 m, which is located in the southeast coastal city of Yueqing in Zhejiang Province. It is well known that the typhoon-induced response is closely related to the safety and stability of the structure. To ensure the safety of the structure, a newly improved Structure Health Monitoring System (SHMS) has been implemented on a membrane building which is one of the largest scale field monitoring projects anywhere in the world, from where the wind-induced response data was obtained for this paper. Based on the measured wind speeds, the wind pressure distribution coefficient of the membrane surface is derived by numerical simulation with Fluent software. Meanwhile, the displacement response is also calculated by ANSYS APDL. Detailed simulation results and field measurement data are compared for the displacement response caused by Typhoon "Chan-Thu". It is shown that the former is larger than the latter with the treatment of equivalent wind load. However, the extreme value of the displacement response of the structure with consideration of fluctuating wind load is relatively much more consistent with the measured value. In conclusion, the wind-induced displacement response calculated by the equivalent static wind load method controlled by the principle of maximum displacement equivalence is suitable for engineering applications and wind resistance design, which will result in a slightly higher displacement response evaluation than the real cases. • Newly developed membrane structure health monitoring system first application for coal-shed building covered by large-span air-supported membrane structure. • Based on the data monitored by the health monitoring system, the wind induced response of a real project with span of 115 m and length of 317 was tested, and the response includes acceleration, displacement, surface wind pressure. • The Typhoon "In-Fa" induced wind displacement response comparison between the simulation result and in-site measured data was carried in detail. [ABSTRACT FROM AUTHOR]

With climate change and urbanization development, urban areas are facing more serious floods. As a result, hydrological and hydrodynamic models have recently shown a broad application prospect in urban flood simulating and forecasting. For the area with rich inland rivers, urban water resources can be effectively regulated and redistributed through river networks and hydraulic structures scheduling. However, the lack of research on the effect of scheduling becomes a major limitation in model applications. Based on a coupled hydrodynamics model, the current study simulates the flooding response to the combined rainstorm and scheduling scenarios and analyzes the river overflow at the community scale. The result indicated that three local regions in the Jin'an study area are inundated easily. The locations near Qinting Lake were more sensitive to the water regulation rules than others. In the model of control on Qinting Lake, section A is more sensitive to the schedule control than section B , while for section A , the water level increased by 1.44% under the return period (RP) (10 a), and the rate changed to 2.64% under the RP (100 a). The differences in inundation from various scenarios are relatively small. In the mode of joint discharge rules under RP (50 a), the water level changed by 4.77% in section A and 1.24% in section B. The simulation at the community scale considers the overflow process, and the results indicated that the total inundation area decreased by 12.8 ha under joint schedules. The significant effects to alleviate urban inundation mainly come from the decreased flood overflow from the channel, but not from the flooding nodes. This study provides promising references for urban flood management. • A coupled hydrological and hydrodynamic model is built for the urban water drainage system in Fuzhou. • The water level of the section near engineering is more sensitive than that of the section far away under scheduling. • Channel overflow and water level boundary both influence the inundation, while channel overflow dominates the influence. [ABSTRACT FROM AUTHOR]

This study aimed to compare the predictive value of six selected anthropometric indicators for benign prostatic hyperplasia (BPH). Males over 50 years of age who underwent health examinations at the Health Management Center of the Second Xiangya Hospital, Central South University (Changsha, China) from June to December 2020 were enrolled in this study. The characteristic data were collected, including basic anthropometric indices, lipid parameters, six anthropometric indicators, prostate-specific antigen, and total prostate volume. The odds ratios (ORs) with 95% confidence intervals (95% CIs) for all anthropometric parameters and BPH were calculated using binary logistic regression. To assess the diagnostic capability of each indicator for BPH and identify the appropriate cutoff values, receiver operating characteristic (ROC) curves and the related areas under the curves (AUCs) were utilized. All six indicators had diagnostic value for BPH (all P ≤ 0.001). The visceral adiposity index (VAI; AUC: 0.797, 95% CI: 0.759-0.834) had the highest AUC and therefore the highest diagnostic value. This was followed by the cardiometabolic index (CMI; AUC: 0.792, 95% CI: 0.753-0.831), lipid accumulation product (LAP; AUC: 0.766, 95% CI: 0.723-0.809), waist-to-hip ratio (WHR; AUC: 0.660, 95% CI: 0.609-0.712), waist-to-height ratio (WHtR; AUC: 0.639, 95% CI: 0.587-0.691), and body mass index (BMI; AUC: 0.592, 95% CI: 0.540-0.643). The sensitivity of CMI was the highest (92.1%), and WHtR had the highest specificity of 94.1%. CMI consistently showed the highest OR in the binary logistic regression analysis. BMI, WHtR, WHR, VAI, CMI, and LAP all influence the occurrence of BPH in middle-aged and older men (all P ≤ 0.001), and CMI is the best predictor of BPH., Competing Interests: None