Multi-model ensemble simulated non-point source pollution based on Bayesian model averaging method and model uncertainty analysis.

Watershed models are cost-effective and powerful tools for evaluating and controlling non-point source pollution (NPSP), while the reliability of watershed models in a management context depends largely on inherent uncertainties in model predictions. The objective of this study is to present the use of multi-model ensemble applied to streamflow, total nitrogen (TN), and total phosphorus (TP) simulation and quantify the uncertainty resulting from model structure. In this study, three watershed models, which have different structures in simulating NPSP, were selected to conduct watershed monthly streamflow, TN load, and TP load ensemble simulation and 90% credible intervals based on Bayesian model averaging (BMA) method. The result using the observed data of the Yixunhe watershed revealed that the coefficient of determination and Nash-Sutcliffe coefficient of the BMA model simulate streamflow, TN load, and TP load were better than that of the single model. The higher the efficiency of a single model is, the greater the weight during the BMA ensemble simulation is. The 90% credible interval of BMA has a high coverage of measured values in this study. This indicates that the BMA method can not only provide simulation with better precision through ensemble simulation but also provide quantitative evaluation of the model structure through interval, which could offer rich information of the NPSP simulation and management.

Effects of in vitro cultivated Calculus Bovis compound on pulmonary lesions in rabbits with schistosomiasis.

AIM: To explore the interventional effects and mechanism of in vitro cultivated Calculus Bovis compound preparation (ICCBco) on pulmonary lesions in portal hypertensive rabbits with schistosomiasis. METHODS: The experimental group included 20 portal hypertensive rabbits with schistosomiasis treated by ICCBco. The control group included 20 portal hypertensive rabbits with schistosomiasis treated by praziquantel. The morphological changes of the pulmonary tissues were observed under light and electron microscopy. The expression of fibronectin (FN) and laminin (LN) in the lung tissues was analyzed by immunohistochemistry. RESULTS: Under light microscope, the alveolar exudation in the lung tissue was more frequently observed in the control group, while the alveolar space was fairly dry in the lung tissue of ICCBco group. Under electron microscope, more alveolar exudation in the lung tissue, and more macrophages, alveolar angiotelectasis and the blurred three-tier structure of alveolar-capillary barrier could be seen in the control group. In ICCBco group, fibers within the alveolar interspace slightly increased in some lung regions, and the structure of type I epithelium, basement membrane and endodermis was complete, and no obvious exudation from the alveolar space, and novascular congestion could be observed. There was a positive or strong positive expression of FN and LN in the lung tissue of the control group, while there was a negative or weak positive expression of FN and LN in ICCBco group. CONCLUSION: ICCBco can effectively prevent pulmonary complications in portal hypertensive rabbits with schistosomiasis by means of improving lung microcirculation and lowering the content of extracellular matrix.