Periodic oscillations of the relativistic pendulum with friction

We consider the existence and multiplicity of periodic oscillations for the forced pendulum model with relativistic effects by using the Poincare-Miranda theorem. Some detailed information about the bound for the period of forcing term is obtained. To support our analytical work, we also consider a forced pendulum oscillator with the special force $\gamma_0\sin(\omega t)$ including a sufficiently small parameter. The result shows us that for all $\omega\in(0,+\infty)$, there exists a $2\pi/\omega$ periodic solution under our settings

Study on Quality Change of Waxberry in Storage Period by Slow Freezing and Fast Freezing

In this study, the effects of slow freezing (−20 ℃) and quick freezing (−80 ℃) on the cell wall structure of waxberry fruits were investigated, and the changes of main nutrient quality components during storage were also studied. The moisture content and migration of waxberry fruits during storage were observed by low field NMR. The results showed that the cell wall morphology of quick-frozen waxberry fruits maintained well, and there were obvious gaps in the cross section of the cell wall of slow-frozen waxberry fruits. During the storage period of 25 days, the water content of fruit gradually decreased, but the range of water transfer of quick-frozen waxberry was small, and the total lateral relaxation time was larger than the relaxation time of slow-frozen waxberry, indicating that quick-frozen waxberry could effectively maintain fruit water activity. The free water signal value of quick-frozen waxberry decreased only by 18%, while the free water signal value of slow-frozen waxberry decreased by 47.75%, indicating that quick-frozen waxberry was beneficial to maintaining fruit water content. In addition, fruit nutrients decreased gradually, but the total sugar content, titratable acid content, total phenols and anthocyanins contents were 13.64 mg/g, 13.43 g/L, 15.43 mg/mL and 0.53 μmol/g, respectively, at the end of storage stage of quick-frozen waxberry. The retention rates of main nutritional indexes were higher than those of slow frozen waxberry. Therefore, quick-freezing can effectively delay the loss of nutrients in waxberry fruits

Achieving fully-equiaxed fine <i>β</i>-grains in titanium alloy produced by additive manufacturing

The achievement of fine equiaxed β grain with conventional intragranular (α-Ti+β-Ti) microstructure in additive manufacturing titanium alloy remains a big challenge. We conquer this challenge by synergistically controlling β-grains during both solidification and subsequent thermal-cycles of laser directed energy deposition (DED), and a solution + quenching heat-treatment. Both the strength and plasticity of heat-treated Ti6Al4V3Ni0.05B are superior to those reported new DED titanium alloy and comparable to that of DED Ti6Al4V, because of the fine-equiaxed β-grains with intragranular (α-Ti+β-Ti) microstructure. These findings provide new insight into the grain structure control and the composition design of AM titanium alloy. The synergetic control of β-grain during both solidification and subsequent thermal-cycling is essential for achieving fully-equiaxed fine β-grains in additively manufactured titanium alloys.</p

<i>In silico</i> screening combined with bioactivity evaluation to identify AMI-1 as a novel anticancer compound by targeting AXL

Recently, some studies have proven that AXL plays a crucial role in the drug resistance of tumors. At present, no AXL inhibitors on the market and it is essential to discover novel compounds targeting AXL to overcome resistance. In this work, based on the anchor structure, 21,313 compounds were obtained by substructure search from more than 400,000 compounds. Then, the Qvina and Ledock were selected for virtual screening to obtain 17 compounds. Next, four compounds (ARRY614, AMI-1, NG25, and Butein) were selected for bioactivity evaluation after hydrogen bond and cluster analysis. Further activity evaluation suggested that the compound AMI-1 is a novel AXL inhibitor with an IC50 value of 1.13 uM. In addition, molecular dynamics simulation demonstrated that compound AMI-1 contained lower binding energy and more key residues than the other three compounds, showing the best inhibitory activity against AXL. Finally, further MM/PBSA prediction showed that AMI-1 is more sensitive to mutant protein 3IKA than wildtype protein 1M17, which means that the AMI-1 may be helpful to overcome the resistance of EGFRT790M mutations. In conclusion, this work successfully discovered a novel compound with moderate inhibitory activity against AXL by a drug discovery workflow, which also could be applied to discover active compounds for other targets quickly. Communicated by Ramaswamy H. Sarma</p