ABSTRACT
The terahertz band is an increasingly important spectrum in a wide range of applications from bioimaging and medical diagnostics to security and wireless communications. We propose a tunable terahertz coherent radiation source based on graphene plasmon-induced transition radiation. The transition radiation in terahertz regime arises from the graphene plasmons, which are excited by a normally incident bunched electron beam. We analyze the field-intensities and spectral-angular distributions of the transition radiation with respect to Fermi energy, substrate dielectric permittivity, and electron bunch energy for both the coherent and incoherent radiation. The effect of electron bunching on the radiation pattern is discussed. The mechanism of plasmon frequency-selective transition radiation is discovered.
ABSTRACT
AIM: To explore mechanism of the cytokines, Th1/Th2 cells and regulatory T cells (Treg), transcription factor Foxp3 in pulmonary function damage of the adjuvant arthritis (adjuvant arthritis, AA) rats. METHODS: 24 Wistar rats were randomly divided into normal control (NC) group and model (Model) groups of 12 to the Model rats right rear paw intradermal injection of 0.1 mL Freund's complete adjuvant-induced inflammation, copied into the AA model. After 48 d inflammation were observed two groups of rat paw swelling degree (E) and the arthritis index (AI), HE staining of lung tissue pathological changes in the calculation factor of two groups of rat lung (LI), alveolitis points, the immune staining detection of Foxp3, TGF-ß1 protein expression. Through the small animal lung function detected by lung function, ELISA determination of cytokine changes in the expression of Treg by flow cytometry. RESULTS: Compared with the NC group, Model rats E, AI, LI, 1 seconds, average expiratory flow (FEV1/FVC%), pulmonary inflammation score, serum TNF-α, Th1/Th2, lung tissue TGF-ß1, CD4(+);CD25(-);T cells, the expression level was significantly higher, and the difference was statistically significant (P<0.05 or P<0.01); forced vital capacity (FVC), 25% lung capacity, peak expiratory flow (FEF25), 50% vital capacity of the peak expiratory flow (FEF50), 75% lung capacity, peak expiratory flow (FEF75), maximum mid-expiratory flow (MMF), forced maximal expiratory flow (PEF), pulmonary dynamic compliance (Cldyn), serum IL-10, CD4(+);Treg, CD4(+);CD25(+);Treg, lung tissue levels of Foxp3 protein expression significantly decreased(P<0.01). Spearman correlation analysis showed that, AA rats with pulmonary function parameters are E, AI, TNF-α, IL-10, Th1/Th2, and CD4(+);Treg, CD4(+);CD25(+);Treg, CD4(+);CD25(-);T cells, Foxp3, TGF-ß1 expression was relevant, and relevant statistical significance (P<0.05 or P<0.01). CONCLUSION: After induced inflammation, antigen stimulation showed hypersensitivity reaction condition in rats, Th1/Th2 imbalance in the state, CD4(+);CD25(-);T cells into CD4(+);CD25(+);Treg blocked, the immune regulatory function of disorders, the release of a large number of cytokines and inflammatory mediators, leading to Local joint disease and lung tissue damage, which occurred AA reduced lung function.
