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[Background] Soil-water characteristic curves(SWCC) is an important input parameter in water and solute transport modeling of unsaturated zone. The VG (van Genuchten) model is a good method to simulate the SWCC. Direct measurements of hydraulic parameters are so tedious and time-consuming that many methods were explored to acquire the VG model parameters in past several decades. But these methods also need sufficient data. [Objective] The objective of this research is to develop a simple method using limited data to obtain the parameters of the VG model. [Method] Five regional soils were selected for the experiment, including black soil, cinnamon soil, loessial soil, red earth, and purple soil. Their saturated soil moisture (θs), soil moisture under 0.33 bar pressure (θ0.33 bar), hygroscopicity at 97% relative humidity of air (θ97%RH) and 43% relative humidity of air (θ43%RH) were measured. Then, the parameters of the VG model were derived from θs, θ0.33 bar, θ97%RH and by using the θ43%RH as residual moisture (θr). The derived parameters were taken into the VG model, and the newly obtained SWCC was compared with the measured soil moisture. [Result] It was found that this method could simulate the SWCC of cinnamon soil well, the residual between the simulated and measured values is generally within 0.01 cm³/cm³; It could also simulate the soil moisture of loessial soil and red earth at 0.33-15 bar well, with residuals generally within ±0.01 cm³/cm³. However, the simulation results of black soil are relatively poor, the residual is negative, within -0.03 cm³/cm³ in low suction (<0.33 bar) section, while at 0.33-15 bar section, the residual is positive, reaching 0.04 cm³/cm³. The simulation results of purple soil are the worst, with a negative residual -0.07 cm³/cm³ in low suction (<0.33 bar); But at 0.33-15 bar, the situation improved and the residual was within 0.03 cm³/cm³. Overall, there is no significant difference between the simulated and measured value through paired t-test, and the correlation coefficient between them is 0.990. The poor results in purple soil could be derived from a low density and large pores in the soil sample, while in black soil may be derived from a strong water holding capacity due to its high organic matter content and good soil structure. [Conclusion] The VG model parameters derived by using θs, θ0.33 bar, θ97%RH and θ43%RH, can effectively predict SWCC. However, for soils with low soil density and large pores, or soils with high organic matter content or good soil structure, it may lead to significant differences in some simulated values. The former may affect the simulation results of the low suction section (<0.33 bar), while the latter may affect the simulation results of the available soil moisture section (0.33-15 bar). [ABSTRACT FROM AUTHOR]

Objective: To investigate the effect of bromodomain and extra-terminal (BET) protein inhibitor JQ1 on expression of autoimmune-related genes in CD4+T cells from patients with systemic lupus erythematosus (SLE).
 Methods: Peripheral CD4+T cells were isolated by positive selection with CD4 microbeads. The percentage of CD4+T cells were detected by flow cytometry. CD4+T cells were treated by JQ1 at 100 nm/L for 6, 24, 48 h. The expression of T cell-related genes was measured by quantitative real-time PCR (qPCR). The secretion levels of cytokines in culture supernatant were measured by ELISA at 48 h.
 Results: The percentage of CD4+T cells isolated by CD4 microbeads is 97.2%. Compared with the control group, the mRNA expression levels of IFNG, IL-17F, IL-21, CXCR5 and FOXP3 were down-regulated at 6, 24 and 48 h (P<0.05), and IL-17A mRNA level was decreased at 6 and 24 h (P<0.01); while IL-4 mRNA level was up-regulated at 24, 48 h (P<0.01), and TGF-β1 mRNA level was up-regulated at 6 and 48 h (P<0.05) in SLE CD4+T cells treated with JQ1. The secretion levels of IFN-γ and IL-21 in JQ1-treated group were decreased significantly (P<0.05), while the secretion levels of IL-4 and TGF-β were up-regulated compared with control group (P<0.05).
 Conclusion: JQ1 can reverse the immune dysregulation and improve the immunity homeostasis in CD4+T cells from patients with SLE.