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Aims Litter is frequently buried in the soil in alpine grasslands due to grassland degradation, serious rodent infestation and frequent strong winds. However, the effects of various litter positions on litter decomposition rates and nutrient dynamics under nitrogen (N) enrichment in such areas remain unknown. Methods A field experiment was performed in the alpine grasslands of northwest China to investigate the influence of litter position (surface, buried in the soil and standing) and N enrichment on litter decomposition, using data from two dominant grass species (Festuca ovina and Leymus tianschanicus) in control and N-enriched plots. Important Findings Litter decomposition rates were much faster in buried litter and slower in standing litter than in surface litter. N enrichment significantly affected litter quality and then influenced decomposition. But no significant differences in litter mass remaining were observed between control and N-enriched soil burial. These results indicated that N enrichment significantly affected litter decomposition by changes in litter quality. In addition, all litter exhibited net carbon (C) and phosphorus (P) release regardless of treatments. Litter exhibited net N accumulation for litter from the control plots but showed N release for litter from N enrichment plots. These suggested that litter decomposition can be limited by N and N enrichment influenced N cycling of litter. Current study presented direct evidence that soil buried litter exhibited faster mass loss and C release, and that soil burial can be a candidate explanation why litter decomposes faster than expected in dryland. [ABSTRACT FROM AUTHOR]

Heavy metal(loid)s in the environment threaten food safety and human health. Health risk assessment of vegetables based on total or bioaccessible heavy metal(loid)s was widely used but can overestimate their risks, so exploring accurate methods is urgent for food safety evaluation and management. In this study, a total of 224 frequently consumed vegetables and their corresponding grown soils were collected from Yunnan, Southwest China. The total contents and bioaccessibilities of heavy metal(loid)s in vegetables were measured, their health risks were evaluated using the non-carcinogenic and carcinogenic risk models provided by USEPA. Besides, the gastrotoxicity of high-risk vegetables was also evaluated using a human cell model. Results showed that 6.25-43.8 % of Cr, Cd, and Pb contents in Zea mays L., Coriandrum sativum L., or Allium sativum L. exceeded the maximum permissible level of China, which were not consistent with those in corresponding soils. The bioaccessibility of Cr, Cd, As, Pb, Cu, Zn, Ni, and Mn in vegetables in the gastric phase was 0.41-93.8 %. Health risks based on bioaccessibility were remarkably decreased compared with total heavy metal(loid)s, but the unacceptable carcinogenic risk (CR > 10 -4 ) was found even considering the bioaccessibility. Interestingly, gastric digesta of high-risk vegetables did not trigger adverse effects on human gastric mucosa epithelial cells, indicating existing health risk assessment model should be adjusted by toxic data to accurately reflect its hazards. Taken together, both bioaccessibility and toxicity of heavy metal(loid)s in vegetables should be considered in accurate health risk assessment and food safety-related policy-making and management., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier B.V. All rights reserved.)

Many crossing hydraulic structures have been constructed in the Middle Route of the South-to-North Water Transfer Project (MR-SNWTP), which increases the likelihood of sudden water pollution accidents. After an accident, managers need to assess the extent of pollution under conditions of gate control, and it's necessary to make suitable emergency control decision under this assessment. Therefore, we researched the rapid prediction of pollutants behaviours under conditions of complicated gate control in this paper, by presenting three characteristic parameters of pollutant migration and diffusion. According to the simulation results, the influencing reasons and rapid prediction formulas for the characteristic parameters (peak transport distance, pollutant longitudinal length and peak concentration) after a sudden water-soluble pollution accident are proposed. Also, the approval results show that the formulas can accurately predict the location and range of the pollutant after the emergency accident. Finally, the rapid prediction formulas for the characteristic parameters played a fundamental role in the decisions involved in the Emergency Environmental Decision Support System is proved by two application examples.

Purpose: Brain tumor resection by craniotomy is associated with a high risk of deep vein thrombosis (DVT). This study evaluated the incidence and preoperative and intraoperative risk factors for DVT within 30 days of surgery., Methods: The analysis included: 1) basic clinical variables (patient age, sex, body mass index [BMI], tumor location, and tumor histology); 2) blood test results before operation, such as leukocytes, platelets, and coagulation parameters; and 3) surgical factors (total amount of blood lost, anesthesia mode, and surgery duration)., Results: Of the 1670 patients, 206 (12.34%) had DVT and nine (0.54%) had both DVT and pulmonary embolism (PE) after surgery. Preoperative and intraoperative factors independently associated with DVT/PE were: older age 46-55 years (odds ratio [OR]: 2.87; 95% confidence interval [CI]: 1.83-4.50; P < 0.001), age 56-65 years (OR: 5.24; 95% CI: 3.27-8.40; P < 0.001), age > 65 years (OR: 6.00; 95% CI: 3.45-10.45; P < 0.001), BMI (OR: 1.03; 95% CI: 1.00-1.05; P = 0.029), activated partial thromboplastin time [APTT] (OR: 0.91; 95% CI: 0.86-0.95; P = 0.000), D-dimer (OR: 1.69; 95% CI: 1.23-2.34; P = 0.001), high-grade glioma (OR: 2.09; 95% CI: 1.28-3.40; P = 0.003), glio-neuronal (OR: 3.30; 95% CI: 1.28-8.47; P = 0.013), craniopharyngioma (OR: 2.16; 95% CI: 1.13-4.10; P = 0.019), and surgery duration (OR: 1.82; 95% CI: 1.27-2.60; P = 0.001)., Conclusions: Older age, BMI, preoperative APTT, D-dimer, tumor histology, and surgery duration independently increased the risk of developing postoperative DVT/PE. These findings provide prognostic information that will guide therapies aimed at minimizing the development of DVT/PE during hospitalization., (Copyright © 2020. Published by Elsevier Ltd.)