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Purpose: To explore the relationship between single-nucleotide polymorphisms (SNPs) in complement factor I (CFI), interleukin-8 (IL-8), transferrin (TF), and transferrin receptor 2 (TFR2) and age-related macular degeneration (AMD) in a northeastern Chinese population. Methods: A total of 400 AMD patients (200 wet AMD and 200 dry AMD) and 200 controls were enrolled in this study, and genetic polymorphisms in the above genes were detected by polymerase chain reaction–restriction fragment length polymorphism (PCR–RFLP). The χ2 test was used to compare differences in allele frequencies in each group, and the associations of genotype frequencies with AMD were determined by multivariate logistic regression analysis. Results: Our research shows that CFI rs141853578, IL-8 rs2227543, TF rs8177178 and TFR2 rs2075674 are associated with the incidence of AMD. In wet AMD, allele T of CFI rs141853578, IL-8 rs2227543 and TFR2 rs2075674 may be a risk factor. Allele A of TF rs8177178 may increase the risk of dry AMD. Conclusions: CFI rs141853578, IL-8 rs2227543, TF rs8177178 and TFR2 rs2075674 genetic polymorphisms are associated with the occurrence of AMD in a northeastern Chinese population, especially wet AMD.

The artificial release of electron adsorbing material can cause electron density to be depleted in the ionosphere, forming the ionospheric holes rapidly. At the same time, the shell structure of the electron density enhancement around the hole is produced, owing to the extrusion of background plasma caused by rapid expansion of the release. The coexistence of ionospheric hole and enhancement structure is the significant characteristics of the early time effects. In this paper, the early time effects of neutral chemicals released into ionosphere are studied, and a physical model of spatiotemporal evolution about early time electron density is set up. At t=1 s, the maximum electron density in the enhanced region is 2.46106 cm-3, approximately 2.8 times as great as background electron density, then the electron density at the boundary gradually decreases. At t=30 s, the maximum electron density is 1.58106 cm-3, which is about 1.7 times the background electron density. At t=120 s the maximum electron density in the enhanced region is 1.12106 cm-3, which is 1.2 times the background electron density. Within 120 s after release, the size of the ionospheric cavity increases gradually; at t=5 s the distribution range of the released chemical material is of a sphere of about 10 km in diameter; at t=120 s the distribution diameter of the released chemical material is more than 70 km, and at the same time, the depletion depth of the ionospheric hole decreases slowly. At t=1 s, the depletion depth of the ionospheric hole is about 100%, and at t=120 s the depletion depth of the ionospheric cavity decreases to 95%. The effects of different-frequency radio waves propagating through ionospheric disturbance at t=10 s and t=120 s are simulated by the ray tracing. At t=10 s, the effect of electron density enhancement is remarkable, and the thickness of the enhancement is about 10 km, and the electronic density enhancement area can reflect the radio wave signal at a frequency as high as 14 MHz. At t=120 s, the phenomenon of electron density enhancement becomes weak, the thickness of the enhanced area continues to increase, and the radio wave signal that the electronic density enhancement area could reflect decreases to 11 MHz. The radio waves at a frequency range between 9 MHz and 12 MHz each have a complex diffraction, focusing and dispersing effect in the disturbed area. Furthermore, according to the working principle of ionospheric vertical measurement instrument and ray tracing theory, the vertical ionization detection figures are obtained through inversion. The results are consistent with previous experimental results of rocket exhaust, which testifies the correctness of proposed model.