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Introduction: Osteoblasts and osteoclasts are cells of osteoblastic origin, and are vital in homeostasis of the skeleton. miRs are important for functioning, survival and differentiation of osteoclasts. It has been reported previously that miR-23b-3p is involved in osteoporosis and in regulation of differentiation of osteoblasts. It is also involved in the process of bone formation. However, the role of miR-23b-3p in differentiation of osteoclasts remains unexplored. Material and methods: CSF-1 and ODF induced osteoclasts were used for the study. RNA isolation was done from TIB-71 cells. TRAP staining was done for TRAP-positive osteoclast formation. PIT assay for bone resorption was performed. For in vivo studies osteoclast-specific miR-23b-3p transgenic mice were developed. Results: The levels of miR-23b-3p were upregulated in bone marrow monocytes during osteoclastogenesis with colony stimulating factor-1 and osteoclast differentiation factor induction, which suggests that miR-23b-3p plays a crucial role in differentiation of osteoclasts. Over-expression of miR23b-3p in bone marrow monocytes leads to osteoclastogenesis, whereas the inhibition ameliorates it. We further studied the function of miR-23b-3p via PI3K/AKT targeting the PTEN pathway. In vivo, osteoclast-specific miR23b-3p transgenic mice showed suppressed PTEN and elevated osteoclast activity, and the mice showed decreased bone mineral density. Conclusions: The results suggest that miR-23b-3p regulates the differentiation of osteoclasts by targeting PTEN through the PI3K/AKT cascade. [ABSTRACT FROM AUTHOR]

In order to explore the effect of nano Mg(OH)2(MH) on the flame retardancy and mechanical properties of nitrile-butadiene rubber (NBR) composite, molecular simulation was employed to examine the following properties of nano-MH/NBR composite, including thermal decomposition temperature, agglomeration and dispersion mechanism, shear behavior, stretcher strain and gyration radius of gyration. Discussion was performed on the microscopic mechanism of the flame retardancy and mechanical properties of nano MH/NBR composite. The simulation results indicated that the introduction of nano MH increased the thermal decomposition temperature of the composites by up to 28.92%, and that compared with the unmodified nano-MH/NBR composite, the thermal decomposition temperature of the conventionally-modified composite was increased by 19.22%. Besides, the crystal morphology, polarity and dispersion of nano-MH could be well optimized by hydrothermal modification. The Young’s modulus of the composite was increased by 35.65% by adding nano-MH into pure NBR. The Young’s modulus of the conventionally-modified nano-MH(101)/NBR and the hydrothermally-modified nano-MH(001)/NBR composite was 20.93 GPa and 21.43 GPa, respectively, an increase of 35.82% and 39.06% compared with unmodified nano-MH/NBR composite, respectively. To conclude, adding nano-MH could improve the flame retardancy and mechanical properties of NBR composite, and modified nano-MH performed better than unmodified nano-MH in NBR composite. [ABSTRACT FROM AUTHOR]

With the substantial increase of vehicles on road, driving safety and transportation efficiency have become increasingly concerned focus from drivers, passengers, and governments. Wireless networks constructed by vehicles and infrastructures provide abundant information to share for the sake of both enhanced safety and network efficiency. This paper presents the systematic research to enhance the vehicle safety by wireless communication, in the aspects of information acquisition through vehicle sensing, vehicle-to-vehicle (V2V) routing protocol for the highly dynamic vehicle network, vehicle-to-infrastructure (V2I) routing protocol for a tradeoff in real-time performance and load balance, and hardware implementation of V2V system with on-road test. Simulations and experimental result validate the feasibility of the algorithms and communication system. [ABSTRACT FROM AUTHOR]