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: Under the changing environment, global drought occurs frequently, which has a great impact on social economy and ecology. Current researches focus on the research and development of drought forecasting technology, but pay little attention to the theory of drought forecasting, such as the temporal and spatial distribution and driving mechanism of drought predictability. This work took the Loess Plateau as the research object, constructed a support vector machine model to forecast regional drought from 2008 to 2019, and quantified drought predictability with Kling, Gupta Efficiency (KGE). Then the spatial distribution characteristics of drought predictability at different time scales were investigated, and the key factors influencing changes in the distribution of drought predictability were identified. The results showed that the drought predictability of the Loess Plateau showed an upward trend with the increase of the time scale. The KGE average of SPEI12 was 73.8% higher than that of SPEI1. The predictability of seasonal drought is the highest in autumn, followed by summer, spring and winter. The drought predictability showed spatial heterogeneity, showing a high distribution pattern in the north and low distribution pattern in the south, and the drought predictability in the central Loess Plateau in spring and in the northwest desert region of the Loess Plateau in winter was extremely low. There were differences in the main factors affecting the predictability of inter, seasonal drought. The highest explanatory power in autumn was temperature, summer and spring was aridity index(AI), and winter was the coupling of air, sea PRE_AMO. Meanwhile, the influence of both variable factors on drought predictability of the Loess Plateau was significantly higher than that of single factor. This study provided a new insight into the predictability of drought and was helpful to further improve the ability of drought forecasting and early warning in the Loess Plateau. [ABSTRACT FROM AUTHOR]

Objective To establish the reference intervals (RIs) of the four biochemical parameters for liver function [aspartate aminotransferase (AST), alanine aminotransferase (ALT), gamma-glutamyl transpeptidase (GGT), and alkaline phosphatase (ALP)] in adults by using the indirect method based on the data of subjects undergoing physical examination in laboratory information system (LIS). Methods With the help of the LIS, related data were collected from the healthy adults who underwent physical examination in Physical Examination Center of The First Hospital of Jilin University from October 2019 to October 2020. The Kolmogorov-Smirnov test was used to check the normal distribution of the original data; data with skewed distribution were transformed into data with approximate normal distribution using the BOX-COX method; the Turkey method was used to remove outliers; the Mann-Whitney U test or the Z-test was used for comparison between groups; the non-parametric method was used to calculate RIs. Results A total of 27 218 subjects were included after the removal of outliers. All four parameters showed age and sex differences. The RIs of AST were 14-39 U/L for male individuals aged 20-79 years, 12-32 U/L for female individuals aged 20-49 years, and 14-39 U/L for female individuals aged 50-79 years; the RIs of ALT were 10-71 U/L for male individuals aged 20-54 years, 10-49 U/L for male individuals aged 55-79 years, 7-43 U/L for female individuals aged 20-49 years, and 9-49 U/L for female individuals aged 50-79 years; the RIs of GGT were 11-70 U/L for male individuals aged 20-64 years, 10-64 U/L for male individuals aged 65-79 years, 6-45 U/L for female individuals aged 20-49 years, and 7-54 U/L for female individuals aged 50-79 years; the RIs of ALP were 38-96 U/L for male individuals aged 20-79 years, 33-89 U/L for female individuals aged 20-49 years, and 40-106 U/L for female individuals aged 50-79 years. The RIs of AST, ALT, and GGT established in this study were similar to those in the industry standards of China (relative deviation < reference change value), and the RIs of all four biochemical parameters were verified by applicability. Conclusion The RIs of the four biochemical parameters for liver function established by the indirect method are relatively consistent with those established by the direct method, which holds promise for application in clinical laboratory. [ABSTRACT FROM AUTHOR]