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Experimental tests and finite element simulation methods were used in this article. The bearing loads and deformation failure modes of laminated cellular cylindrical shell under axial compression loads were studied. Two kinds of cellular units, regular hexagon and re-entrant, were studied. The influence of different heights, diameters and thicknesses on the axial bearing loads were discussed with laminated cellular cylindrical shell. It is concluded that the axial compression performance of re-entrant cylindrical shell is better than regular hexagonal cylindrical shell. The buckling deformation modes of laminated cellular cylindrical shell under axial compression were analyzed. In addition, the material parameters obtained by the test were used to simulate the experimental results, compared the deformation modes and compression performance of simulation and experimental results.

The single layer re-entrant honeycomb cylindrical shell with different angles is established in this paper. Based on the single layer re-entrant honeycomb cylindrical shell with different angles, a novel composite re-entrant honeycomb cylindrical shell is proposed. The deformation behavior of single and multi-layer re-entrant honeycomb cylindrical shells under axial impact was studied by numerical simulation. By comparing and analyzing the plateau stress and specific energy absorption of single and multi-layer re-entrant honeycomb cylindrical shells under different impact velocities. The following conclusions can be obtained: compared with the single-layer re-entrant honeycomb cylindrical shell, the energy absorption capacity of the multi-layer re-entrant honeycomb cylindrical shell is significantly improved under the same density and size. The deformation position of re-entrant honeycomb cylindrical shell is changed with different impact velocities.The multi-layer re-entrant honeycomb cylindrical shell doesn′t show negative Poisson’s ratio.

Using finite element simulation and experimental testing methods, with three stiffened rib configurations as the research object, the effect of the stiffened rib configuration on the mechanical behavior of the stiffened plate structure is analyzed under the given material parameters and geometric parameters of the stiffened plate. And the method of sine curve instead of straight line is used to optimize the structure. The research shows that the reinforcement effect of the plate is better than the positive distribution when the square configuration is distributed in the 45° direction, and the vertical distribution of the regular hexagon and the inner concave configuration has better plate reinforcement effect than the horizontal distribution and the 45° direction distribution; the smaller the angle between the pores of the stiffened configuration is, the better the reinforcement effect of the plate is; the use of sinusoids in the stiffened layer instead of the straight line boundary can significantly improve the bearing capacity of the stiffened plate; through the analysis of the crack path of the stiffened plate, it can be obtained that all the stiffened layers of the stiffened plate expand along the longitudinal rib wall at the load-bearing position after bending and deformation.

Virus has caused great distress to human health. Based on the lack of specific target sites and therapy of various viruses, this article highlights circadian rhythm, the biological clock that tells the body to do the correct thing according to the time, as a significant part in regulating human resistance to virus. Also, it summarizes how some core clock genes within human body regulate the intrusion and the replication of several kinds of viruses, together with the corresponding regulating methods to change the clock gene levels in dealing with the infection. After comparing the methods, it then comes to a conclusion which underlines the generality of REV-ERB in rejecting almost all of the viruses questioned. It regards applying REV-ERB enhancers like SR9009 and GSK4112 in a dose-dependent manner as an effective direction in designing relevant therapies. Besides, it puts circadian rhythm as an efficient researching direction for the later researches for other kinds of viruses.

Many physiological and pathophysiological processes in cells or tissues are involved in mechanical stretch, which induces the gap junction gene expression and cytokine TGF beta changes. However, the underlying mechanisms of the gap junction gene expression remain unknown. Here, we showed that the mRNA and protein levels of Cx43 in human umbilical vein endothelial cells (HUVECs) were significantly increased after 24 h stretch stimulation, and TGF beta1 (not TGF beta2) expression was also upregulated. Administration of TGF beta1 into HUVECs without stretch also induced upregulation of Cx43 expression. However, SB431542, a specific inhibitor of the TGF beta1 receptor, blocked the Cx43 protein upregulation caused by TGF beta1. Further, the increase of Cx43 protein expression under the stretch condition was partially blocked by SB431542; it was also partially blocked by simultaneous administration of anti-TGF beta1 monoclonal neutralization antibody. Importantly, the upregulation of Cx43 induced by stretch was blocked by the administration of actin and microtubule inhibitors, while NEDD4, a key element in mediating Cx43 protein ubiquitination and degradation, was not changed under the stretch condition. In conclusion, upregulation of Cx43 expression under the 24 h stretch condition is mediated via TGF beta1 receptor signaling pathway, and it also involves the actin and microtubule cytoskeletal network.