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Objectives: HIV‐1 genetic diversity is increasing among men who have sex with men (MSM) in China, but the association of HIV‐1 genotype with disease progression remains to be elucidated. Methods: We collected data in an observational longitudinal cohort study of 860 HIV‐1‐infected MSM in Guangzhou, China between January 2008 and March 2017. Kaplan‐Meier analysis and Cox proportional hazard model were used to predict the time from HIV‐1 diagnosis to immunodeficiency progression (CD4 cell count < 200 cells/μl) as well as adjusted hazard ratio (aHR). Results: CRF01_AE and HIV‐1 subtype B infection were associated with higher percentage of patients progressed to immunodeficiency and higher incidence of immunodeficiency than infection with CRF07_BC or CRF55_01B. Compared with CRF07_BC, the time from HIV‐1 diagnosis to immunodeficiency were different among the major HIV‐1 genotypes, which ranked as follows, in descending order: CRF07_BC (7.03 years) > CRF55_01B (5.71 years, P = 0.014; aHR 3.752, P = 0.0923) > CRF01_AE (5.18 years, P < 0.001; aHR 4.733, P = 0.0152). HIV‐1 genotype, viral load and baseline CD4 T‐cell count were three independent variables associated with disease progression. Conclusions: Our results confirm differential rates of immunodeficiency progression as a function of HIV‐1 genotype. The impact of HIV‐1 genotype on HIV epidemics, patient management and prevention should be further investigated. [ABSTRACT FROM AUTHOR]

To study the dynamic characteristics of filamentary structure during the edge-localized mode (ELM) burst on the experimental advanced superconducting tokamak, the BOUT++ six-field two-fluid model is used to simulate the temporal and spatial evolutions of the ELM filaments. In the peak gradient region at the outer mid-plane, the radial speed of filaments is changed frequently and varied from 0.11 km/s to 0.79 km/s, and the poloidal speed oscillates in the range of 0.61–0.85 km/s. The width of the ELM filaments is increased from 7.76 mm to 26.7 mm and grows rapidly to 41.99 mm from t = 0.2717 ms to 0.2831 ms after the start of the burst. After that, the width decreases gradually and stabilizes at 25–30 mm when it comes to the saturation phase. Further research indicates that the filament propagation speed is increased during their outward movement. The width gradually decreases when the filaments move outward, and it is proportional to electron temperature (Te) perturbation. All the results are consistent with the experimental data presented by Chen et al., IEEE Trans. Plasma Sci. 47, 799 (2019). [ABSTRACT FROM AUTHOR]

An axisymmetric magnetic oscillation (AMO) of 5–10 kHz in the L-mode plasma edge has been studied on an experimental advanced superconducting tokamak. The analysis shows that this oscillation only occurs at the plasma very close to the L-H transition. The structure of magnetic oscillation is axisymmetric (n = 0) toroidally and demonstrates an m = 2 standing wave in the poloidal direction. The density fluctuation of AMO measured by reflectometry at the midplane is nearly in phase, indicating that the AMO is not a radial traveling wave. The AMO shows an obvious modulation effect on the background magnetic/density fluctuation, and as a result, the edge density/density gradient and particle flux onto the divertor are also modulated by the AMO. The frequency scaling of the AMO is f m ∝ (∇ n e / I p 2 ) − 1 . The bicoherence analyses show a strong nonlinear interaction between the AMO and the background turbulence, and other nonlinear interactions between the AMO and three other coherent fluctuations with frequencies (∼4, ∼11, and ∼15 kHz) are also found. [ABSTRACT FROM AUTHOR]