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[Objective] The influences of barrier height (H), porosity (P), and row spacing (R) on the erosion protection of a vertical sunflower sand barrier were studied in order to provide a theoretical basis for optimizing the parameter configuration of a vertical sunflower stalk sand barrier and the development of a vertical sand barrier wind and sand control project. [Methods] Based on field observations of wind speed and sand transport, research on the variation characteristics of sand barrier roughness, windproof effect, and sand blocking effect under different parameter configurations was conducted. [Methods] ① The main windproof area of the sand barrier was 0—50 cm above the soil surface. Compared with the roughness of the bare dune sand barrier, the roughness was increased by 7.70—214.45 times, the windproof effect of each specification of sand barrier was in the range of 11.74%—59.45%, and the sand barrier effect was in the range of 33.06%—92.23%. ② The wind and sand barrier effect of the sand barrier increased with an increase in barrier height, and decreased with an increase in porosity and row spacing. The influence of barrier height on the wind protection effect was greater than the influence of porosity, and the influence of porosity on the sand barrier effect was greater than the influence of barrier height. ③ The windproof effect and sand barrier effect of H(30 cm)-P(40%)-R(2 m), H(30 cm)-P(50%)-R(1 m), H(40 cm)-P(40%)-R(2 m), H(40 cm)-P(50%)-R(2 m) reached 35% and 75%, respectively. [Conclusion] A vertical sunflower stalk sand barrier can effectively reduce wind speed and sand transport amount. Sand barrier parameters are the key to affecting the protective effect of a sand barrier. The most important parameters affecting the windproof effect and sand barrier effect of a sand barrier are barrier height and porosity.

Objective: To clarify the relationship between the expression of alpha- and beta-isoform of corticosteroid receptors (CS) in peripheral blood mononuclear cell (PBMC) and response to corticosteroid in patients with allergic rhinitis (AR)., Methods: Semi-quantitative RT-PCR was used to detect the expression of CS-alpha, beta in PBMC in patients with AR and to observe the different responses to corticosteroid in controls. Immunocytochemical assay was used to detect the expression of protein of CS-alpha and CS-beta., Results: 1) The expression of CS-alpha mRNA was detected in the sensitive group and the resistant group of patients with AR and the controls with CS-alpha/GAPDH mRNA (x +/- s) 1.15 +/- 0.75, 1.63 +/- 0.78, 1.27 +/- 0.51 respectively. 2) The expression of CS-beta mRNA in PBMC in the resistant group of patients with AR was significantly higher than that in the sensitive group and the controls (P < 0.05), with CS-beta/GAPDH mRNA 1.42 +/- 0.73, 0.82 +/- 0.59, 0.80 +/- 0.68 respectively. 3) The number of CS-beta-positive PBMC in the resistant group was significantly higher than that in the sensitive group and the controls (P < 0.01), with the number of CS-beta-positive PBMC 28.8% +/- 9. 9%, 5.9% +/- 3.2%, 5.5% +/- 6.8% respectively., Conclusions: It is shown that the excessive expression of CS-beta may serve as a novel predictor of corticosteroid resistance in patients with AR.