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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.

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]

Based on fracture mechanics theory, a finite element method was used to determine the stress intensity factors of the inclined crack on the inner surface of the pipe under axial compression load and external pressure. The effects of different influencing factors on the stress intensity factor along the crack front considering crack closure were systematically explored, which were different to those under internal pressure. The effects of high aspect ratio on KII, the crack inclination asymmetry caused by curvature and the effects of the friction coefficient on the stress intensity factors of the pipe with an inclined inner surface crack under axial compression load and external pressure were explored in this paper. To be fit for defect assessment, the solutions for stress intensity factors KII and KIII were derived, and new correction factors fθ and fμ were proposed in the empirical solutions to accommodate the crack inclination asymmetry and the friction coefficient, respectively. [ABSTRACT FROM AUTHOR]

Multiaxial low cycle fatigue tests under non‐proportional stress (NPSS) controlled mode were performed on commercial pure titanium (CP‐Ti). Strain responses of axial and torsional channels under highly applied stress amplitudes show an initial hardening phenomenon. Non‐proportional hardening coefficient of CP‐Ti is independent of the controlled mode. The critical plane of CP‐Ti under NPSS controlled mode is aligned with the maximum principal stress plane proved by optical microscopy observation. Optimized FSM model and KBM‐PM model with mean axial and torsional strain are established. These models are further integrated into equations related to multiaxial stress ratio with high accuracy of life prediction for CP‐Ti under NPSS controlled mode. Highlights: Non‐proportional hardening coefficient of CP‐Ti is independent of the controlled mode.The critical plane of CP‐Ti is aligned with the maximum principal stress plane.Energy and optimized critical plane model with mean strain are established. [ABSTRACT FROM AUTHOR]