ABSTRACT
Recent measurements of microwave and x-ray emission during edge localized mode (ELM) activity in tokamak plasmas provide a fresh perspective on ELM physics. It is evident that electron kinetics, which are not incorporated in standard (fluid) models for the instability that drives ELMs, play a key role in the new observations. These effects should be included in future models for ELMs and the ELM cycle. The observed radiative effects paradoxically imply acceleration of electrons parallel to the magnetic field combined with rapid acquisition of perpendicular momentum. It is shown that this paradox can be resolved by the action of the anomalous Doppler instability which enables fast collective radiative relaxation, in the perpendicular direction, of electrons accelerated in the parallel direction by inductive electric fields generated by the initial ELM instability.
ABSTRACT
BACKGROUND: Increased numbers of TCRαß(+)CD4(-)CD8(-) T cells in the peripheral blood of systemic lupus erythematosus (SLE) patients in the United States and United Kingdom have been reported. However, the proportions of TCRαß(+)CD4(-)CD8(-) T cells and their involvement in the pathogenesis of SLE in Chinese populations are yet to be determined. METHODS: A total of 120 SLE patients, 38 rheumatoid arthritis (RA) patients and 43 normal control subjects were examined. The proportion of TCRαß(+)CD4(-)CD8(-) T cells in the peripheral blood, Fas expression on these cells, and intracellular cytokine levels in these cells were assessed using flow cytometry. Plasma cytokine concentrations were measured using enzyme-linked immunosorbent assay. RESULTS: The percentages of TCRαß(+)CD4(-)CD8(-) T cells were increased in Chinese SLE patients, particularly in active SLE patients, correlated with decreased Fas expression on these cells. IL-17 and IL-21 levels in the blood and in TCRαß(+)CD4(-)CD8(-) T cells from SLE patients were increased. Moreover, a positive correlation was evident between IL-17- and IL-21-producing TCRαß(+)CD4(-)CD8(-) T cells. CONCLUSIONS: Increased TCRαß(+)CD4(-)CD8(-) T cells expressing inflammatory cytokines, such as IL-17 and IL-21, may be implicated in the pathogenesis of SLE in patients. Appropriate IL-17- and/or IL-21 blockage may be utilized as a novel immunotherapeutic strategy for SLE patients.
