ABSTRACT
The Qinghai-Tibet Plateau (QTP) has the largest amount of permafrost in the low and middle latitudes, making it highly susceptible to the effects of global warming. In particular, the degradation of permafrost can be intensified by anomalous amplified warming. To accurately model the hydrothermal dynamics of permafrost and its future trends, the accumulation of high-precision, long-term data for the soil thermal conductivity (STC) in the active layer is crucial. However, no previous research has systematically investigated the spatio-temporal variation in the STC on the QTP over an extended period. Therefore, this study aims to fill this gap using the XGBoost model to analyze the STC in the permafrost on the QTP from 1980 to 2020. The findings of this study provide some preliminary insights. First, areas with high variation in the STC between the freeze-thaw periods over the 40 years gradually migrated from the western region to the central region. Second, since 2015, STC in more than 90 % of the permafrost region in the thawing period has shown positive growth. While, during the freezing period, the STC also exhibited an increase over most regions of the QTP, though the western region and parts of the northeastern region exhibited a decrease. Third, the spatial center of gravity for the STC during the freezing and thawing periods from 1980 to 2020 shifted. The mean STC was larger in the eastern and northeastern regions during the freezing period and larger in the western region during the thawing period. Fourth, both alpine swamp meadow and alpine meadow exhibited a gradual increase in the STC during the freeze-thaw period from 1980 to 2020. The conclusions and data products from this study are expected to support spatiotemporal modeling of the permafrost on the QTP and assist in the prognosis for its future.
ABSTRACT
OBJECTIVE: To establish an animal model of alcoholic fatty liver (AFL) and to observe the prevention and treatment with New Qinggan Decoction (NQGD). METHODS: Female SD rats were exposed to the mixture of white spirit and corn oil continuously for up to 6 weeks via an intragastric feeding protocol. The pathologic alteration of the liver and the changes of serum lipid were observed, and the effect of NQGD for preventing and treating AFL was studied. RESULTS: Wide hepatic steatosis was induced in model group rats. Serum triglyceride (TG) and total cholesterol (TC) of the model group were higher than those of the normal group (P<0.01). Serum aspartate aminotransferase (AST) and alanine aminotransferase (ALT) of the model group were higher than those of the normal group (P<0.05). In NQGD group, hepatic steatosis was milder than that in the model group, and serum TG, TC, AST, ALT descended significantly as compared with the model group (P<0.01). CONCLUSION: AFL model of rats established by feeding the mixture of white spirit and corn oil is similar to the episode of the human AFL, and is easy to intervene with medicine. NQGD can prevent the occurrence of AFL in this model.
ABSTRACT
Objective:To study the protective and therapeutic effects of Zengshengxiao Capsules (ZSX) on atrophic gastritis in rats. Methods: The model was established by methods of active immunity and gastrogavage with bile and hot water. The method of acetic acid writhing was used. Results: (ZSX) had actions of promoting the blood flow of gastric mucosa, increasing in pH, inhibiting inflammatory cell infiltration, glandular atrophia and atypical hyperplasia. It also had action of alleviating pain. There were no toxic and side effects. Conclusion: (ZSX) had remarkably preventive and therapeutic effects on atrophic gastritis of rats.
