In this paper, we examine the three-level optical Stark effect of excitons in InGaAs/InAlAs quantum dots using renormalized wavefunction formulation. The system was assumed to be irradiated by two lasers in which a strong laser dynamically couples electron-quantized levels, while a weaker laser probes interband absorption. Our results show that, in the presence of the resonant strong laser, two new absorption peaks of excitons appear in the absorption spectrum as a clear indication of the effect. In addition, we propose that the formation of the effect in lowdimensional structures could have connection to the splitting of electron levels. Furthermore, we seek to explain the essential dependence of the amplitude and position of two peaks on pump field detuning.

Pandemic H1N1 influenza A (H1N1pdm) elicits stronger pulmonary inflammation than previously circulating seasonal H1N1 influenza A (sH1N1), yet mechanisms of inflammatory activation in respiratory epithelial cells during H1N1pdm infection are unclear. We investigated host responses to H1N1pdm/sH1N1 infection and virus entry mechanisms in primary human bronchial epithelial cells in vitro. H1N1pdm infection rapidly initiated a robust inflammatory gene signature (3 h post-infection) not elicited by sH1N1 infection. Protein secretion inhibition had no effect on gene induction. Infection with membrane fusion deficient H1N1pdm failed to induce robust inflammatory gene expression which was rescued with restoration of fusion ability, suggesting H1N1pdm directly triggered the inflammatory signature downstream of membrane fusion. Investigation of intra-virion components revealed H1N1pdm viral RNA (vRNA) triggered a stronger inflammatory phenotype than sH1N1 vRNA. Thus, our study is first to report H1N1pdm induces greater inflammatory gene expression than sH1N1 in vitro due to direct virus-epithelial cell interaction.

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This paper presents a theoretical investigation of quantum beats of excitons in GaAs/AlGaAs circular cylindrical quantum wires. A three-level model of excitons, including a ground state and two excited states, has been applied to derive the renormalized wavefunctions and the time-dependent absorption intensity of excitons when the system is irradiated by a strong pump laser resonating with the distance between the two excited-levels. Our results show that a periodic oscillation form of the absorption intensity, obvious evidence of the quantum beat behavior, has appeared. Furthermore, the mechanism of the generation, as well as the effects of the wire radius and the pump laser detuning on the frequency (period) and amplitude of quantum beats, have been explained in detail. These results suggest potential applications in the fabrication of some quantum computation devices.