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Foamy viruses belong to the Spumaretrovirinae subfamily member of the Retroviridae family and produce nonpathogenic infection to hosts in the natural conditions. However, infections of foamy viruses can dramatically cause severe cytopathic effects in vitro. To date, the exact molecular mechanism has remained unclear which implied the tremendous importance of virus-host cell immune reactions. In this study, we found that the transactivator Tas in two foamy viruses isolated from Old World Monkey (OWM) induced obvious inhibition of cell proliferation via the upregulation of Foxo3a expression. It was mediated by the generation of ROS and the initiation of ER stress, and ultimately, the mitochondrial apoptosis pathway was triggered. Notably, PFV Tas contributed to the accumulation of G0/G1 phase cycle arrest induced by the activation of the p53 signaling pathway and the nuclear transportation of HDAC4 via upregulating PPM1E expression. Together, these results demonstrated the different survival strategies by which foamy virus can hijack host cell cytokines and regulate virus-host cell interactions.

By experimental methods, 26 specimens were designed to conduct elastic and elastic–plastic buckling tests on cylindrical shells containing cracks. This study discusses the influence of factors such as the length–diameter ratio, the diameter–thickness ratio, the crack length, the inclination of the crack, etc., on the buckling load. Additionally, finite element models were established to compare with experimental results. For the PMMA cylindrical shell, the results showed that as the length–diameter ratio of the cylindrical shell increased, the buckling load first decreased and then increased. For the 6063 aluminum alloy cylindrical shell, with increasing length–diameter ratio, diameter–thickness ratio, and crack length of the cylindrical shell, the buckling load decreased accordingly. However, concerning the crack inclination, as the crack inclination increased, the buckling load increased accordingly. This indicates that the larger the crack inclination, the higher the load capacity of the cylindrical shell containing cracks. Through finite element simulations of cylindrical shells with cracks, it was found that through compressive mechanical properties, both elastic and elastic–plastic buckling loads yielded results that are closer to the experimental results. Additionally, the inclusion of contact effects in numerical simulations further improved the agreement with the experimental results, and the variation trend of the buckling load in the finite element simulation was consistent with the experimental results. The research findings provide valuable references for the assessment of load capacity in structures containing cracks. [ABSTRACT FROM AUTHOR]

The effective flood storage volume of flood storage and detention area is the real capability of occupying flood, which is a fundamental basis when formulating and optimizing real-time the flood dispatching plan in flood storage and detention area. The dispatch of inland river flood will occupy the flood storage volume of lakes, polders and swales in the flood storage and detention area, reducing the effective flood storage volume. This paper selects the flood storage and detention area of Longsai Lake, Hanbei River as an example, calculates and analyzes the flood storage volume and its variation characteristics of lakes, polders and swales occupied by the inland river flood dispatching at different frequencies as well as the change rule of the effective flood storage volume after dispatching inland river flood and its influence. The results show that: ➀ When there are lakes, polders and swales in a flood storage and detention area, the flood storage volume of lakes occupied by the dispatching of inland river flood is significantly greater than those of polders and swales, and the greater the inland river flood, the greater the difference in flood storage volume occupied between lakes versus polders and swales. When the 5-year to 50-year occurrence flood happens in the inland river of the Longsai Lake flood storage and detention area, the flood storage volume occupied by lakes are 97.9%~98.1% in all dispatching volume. ➁ The reduction of the effective flood storage volume in flood storage and detention area caused by inland river flood dispatching changes with the frequency of inland river flood. The greater the flood in the inland river, the more significant the reduction of effective flood storage volume in flood storage and detention area. When the 50-year occurrence flood happens in the inland river of the Longsai Lake flood storage and detention area, the effective flood storage volume decreases by about 13.5%, and when the 5-year occurrence flood happens, the effective flood storage volume decreases by 7.81%. ➂ When the inland river flood occurs and is likely to encounter the flood of the mainstream, the reduction of effective flood storage volume will influence the flood dispatching plan obviously, and the effective flood storage volume of the flood storage and detention area shall be calculated and determined in real time according to the incoming flow, and the dispatching plan shall be optimized or adjusted, the personnel and property shall be transferred in advance. [ABSTRACT FROM AUTHOR]