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Fracture repair is a complex biological process that requires the cooperation of various types of cells and materials. Today, various techniques such as low-density pulse ultrasonography and electrical stimulation are used to accelerate bone healing. The therapeutic effects of ozone on bone repair have been considered in recent years. The purpose of this study was to evaluate the effect of ozone gas on the speed of full-thickness bone defect healing. We selected 30 male weight equal rabbits and, in aseptic surgery, resected a 3-mm-thick piece of full-thickness of bone. Then we divided randomly them into two equal groups, the control, and the recipient. In the first, second, third, and sixth weeks of the radiographed bones were obtained. Also, in the third, sixth, and eighth weeks of each group, 5 rabbits were euthanized and their bones were histopathologically evaluated. Results from the second to sixth weeks of the study showed a significant difference between the treatment group and the control group. This difference was indicative of an increase in the rate of bone healing in the treatment group. Ozone therapy can therefore be considered effective in bone healing. [ABSTRACT FROM AUTHOR]

In this paper, we show how the absorption and re-radiation energy from molecules in the air can influence the Multiple Input Multiple Output (MIMO) performance in high-frequency bands, e.g., millimeter wave (mmWave) and terahertz. In more detail, some common atmosphere molecules, such as oxygen and water, can absorb and re-radiate energy in their natural resonance frequencies, such as 60 GHz, 180 GHz and 320 GHz. Hence, when hit by electromagnetic waves, molecules will get excited and absorb energy, which leads to an extra path loss and is known as molecular attenuation. Meanwhile, the absorbed energy will be re-radiated towards a random direction with a random phase. These re-radiated waves also interfere with the signal transmission. Although, the molecular re-radiation was mostly considered as noise in literature, recent works show that it is correlated to the main signal and can be viewed as a composition of multiple delayed or scattered signals. Such a phenomenon can provide non-line-of-sight (NLoS) paths in an environment that lacks scatterers, which increases spatial multiplexing and thus greatly enhances the performance of MIMO systems. Therefore in this paper, we explore the scattering model and noise models of molecular re-radiation to characterize the channel transfer function of the NLoS channels created by atmosphere molecules. Our simulation results show that the re-radiation can increase MIMO capacity up to 3 folds in mmWave and 6 folds in terahertz for a set of realistic transmit power, distance, and antenna numbers. We also show that in the high SNR, the re-radiation makes the open-loop precoding viable, which is an alternative to beamforming to avoid beam alignment sensitivity in high mobility applications. [ABSTRACT FROM AUTHOR]