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【Background and objective】 Hydrological process is a complex phenomenon and affected by many biological and physical processes. Its modelling in water resource management and decision-making in watershed or catchment is often based on conceptual models where the complicated processes that directly or indirectly modulate water flow in different components are highly simplified. Such models are mathematically simple and have been widely used in both practical and scientific communities. Different conceptual hydrological models are available, but how they compare with each other for simulating hydrological processes in watersheds is not well studied. The purpose of this paper is to fill this gap. 【Method】 We compared 45 conceptual hydrological models for their application in the Lijiang River Basin. For each model, we simulated daily runoff in the basin from 2008 to 2016 using the same dataset, and compared and analyzed their performance in terms of model structure, calculated evapotranspiration and runoff, from which we identified main factors which affect model applicability and accuracy most. 【Result】 MODHYDROLOG was the model that worked best for simulating hydrological flow in the basin, followed by GR4J, IHACRES and Hillslope models. Model which was least accurate for simulating runoff did not work well for modelling real evapotranspiration and other runoff components neither. An accurate evapotranspiration calculation was not decisive for accurate runoff simulation, and dividing the runoff into different components was the key factor in applicability and accuracy of the models. We also found that the generalized semi-distributed model not only simplified the operation process of the model, but also affected the simulation accuracy. 【Conclusion】 Among the 45 conceptual models we compared, MODHYDROLOG, GR4J, IHACRES and Hillslope models worked best for simulating hydrological processes in the Lijiang River Basin and similar basins.

Background: Lipids have a significant impact on the development and functioning of the nervous system, but the sex differences between the association of LDL/HDL, which reflects lipid metabolic status, and cognitive impairment remains unclear. Objective: We aimed to determine if there were sex differences between the association of LDL/HDL and cognitive function in US older adults. Methods: This population-based cross-sectional study used data from the National Health and Nutrition Examination Survey (NHANES) 2011–2012 and 2013–2014 cycles. The main outcome was poor cognitive performance defined by the Digit Symbol Substitution Test (DSST) < 34 based on published literature. Results: A total of 1,225 participants were included in the study, with a cognitive impairment incidence of 25.6% (314/1,225). Multivariate regression models demonstrated a significant association between cognitive decline and each 1-unit increase in LDL/HDL, after adjusting for all covariates (adjusted odds ratio [OR] = 1.36, 95% confidence interval [CI]: 1.11–1.67). Furthermore, subgroup analysis revealed an interaction between LDL/HDL and cognitive impairment in sex subgroups. Conclusions: LDL/HDL was associated with cognitive impairment in the US older adult population in adjusted models, although the significance of this association was not observed in females. [ABSTRACT FROM AUTHOR]

Exploring the spatial and temporal evolution of land use change and habitat quality is of great significance to the ecological protection and high-quality development of the three northeastern provinces. This paper selects the land use and cover data of the three northeastern provinces in 2000, 2005, 2010, 2015 and 2018, and uses ArcGIS and InVEST models to quantitatively analyze the spatial and temporal changes of land use and habitat quality in the three northeastern provinces from 2010 to 2018 according to the classification of"ecological-production-living"land use function. The results show that there are significant differences in the spatial distribution pattern of the three northeastern provinces from 2000 to 2018. The land use types have changed significantly, among which the increase of agricultural production land is the most obvious, reaching 10 604.28 km2, and the most obvious reduction of land use area is forestry ecological land, with a total reduction of 19 400.4 km2. From 2000 to 2018, the habitat quality level of the three northeastern provinces showed a downward trend on the whole, and the area of low-level habitat quality continued to expand, with an increase of 19 369 km2. The area with medi um habitat quality is also expanding, and its area has increased by 20 807 km2. The areas with good habitat quality and excellent habitat quality decreased by 19 991 km2 and 10 185 km2 respectively. The spatial distribution of habitat quality is closely related to the distribution of land use types. Areas with high habitat quality are mostly distributed in areas where woodland ecological space and grassland ecological space are widely distributed, while areas with low habitat quality tend to have a higher proportion of living space and production space than ecological space. [ABSTRACT FROM AUTHOR]