In a previous study, we described the diverse growth capabilities of circulating seasonal influenza A viruses (IAVs) with low to high viral copy numbers in vitro. In this study, we analyzed the cause of differences in growth capability by evaluating pro-inflammatory cytokines (TNF-α, IL-6, IFN-β) and antiviral interferon-stimulated genes (ISG-15, IFIM1, and TRIM22). A549 cells (3.0 × 105 cells) were inoculated with circulating seasonal IAV strains and incubated for 6 and 24 h. In cells inoculated for 6 h, IAV production was assessed using IAV-RNA copies in the culture supernatant and cell pellets to evaluate gene expression. At 24 h post-infection, cells were collected for IFN-β and ISG-15 protein expression. A549 cells inoculated with seasonal IAV strains with a high growth capability expressed lower levels of IFN-β and ISGs than strains with low growth capabilities. Moreover, suppression of the JAK/STAT pathway enhanced the viral copies of seasonal IAV strains with a low growth capability. Our results suggest that the expression of ISG-15, IFIM1, and TRIM22 in seasonal IAV-inoculated A549 cells could influence the regulation of viral replication, indicating the existence of strains with high and low growth capability. Our results may contribute to the development of new and effective therapeutic strategies to reduce the risk of severe influenza infections.

A magnetic skyrmion is stabilized via the Dzyaloshinskii–Moriya interaction in a perpendicularly magnetized thin nanowire. When the skyrmion is driven by a spin-transfer torque due to spin currents flowing through the wire, the skyrmion approaches the wire edge owing to the skyrmion Hall effect. In other words, the skyrmion moves obliquely along the longitudinal direction of the wire. The skyrmion often breaks or disappears because of this oblique motion. In this study, we propose an elliptical skyrmion to prevent this disappearance. We simulated the current-induced motion of an elliptical skyrmion produced in a wire through a micromagnetic approach. The elliptical skyrmion was also moved obliquely to the longitudinal direction of the wire. When a small current flowed through the wire, the skyrmion moved in the longitudinal direction of the wire after it approached the wire edge. When a larger current flowed through the wire, the skyrmion disappeared after it approached the wire edge. The elliptical skyrmion can be driven over a long distance with a larger current compared to a circular skyrmion. The motion of the skyrmion approaching the wire edge was analyzed using Thiele’s equation, with an external force. We estimated the external force from the simulation results of the skyrmion motion. The external force was proportional to the distance between the skyrmion edge and the wire edge. The results of this study indicate that using the elliptical skyrmion as a binary digit in a magnetic memory, such as a skyrmion-based racetrack memory, can be advantageous in term of the stability of the binary digit.

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Multivoxel pattern analysis (MVPA) has become a standard tool for decoding mental states from brain activity patterns. Recent studies have demonstrated that MVPA can be applied to decode activity patterns of a certain region from those of the other regions. By applying a similar region-to-region decoding technique, we examined whether the information represented in the visual areas can be explained by those represented in the other visual areas. We first predicted the brain activity patterns of an area on the visual pathway from the others, then subtracted the predicted patterns from their originals. Subsequently, the visual features were derived from these residuals. During the visual perception task, the elimination of the top-down signals enhanced the simple visual features represented in the early visual cortices. By contrast, the elimination of the bottom-up signals enhanced the complex visual features represented in the higher visual cortices. The directions of such modulation effects varied across visual perception/imagery tasks, indicating that the information flow across the visual cortices is dynamically altered, reflecting the contents of visual processing. These results demonstrated that the distillation approach is a useful tool to estimate the hidden content of information conveyed across brain regions.