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Light fidelity considers a promising technology for wireless communications, it is assumed more secure and couldn't interface with another source. The technique depends on the line of sight between bi-directional sending and receiving sides, challenges are signal attenuation due to propagation non-line-of-sight, which can influence the power signal received from the receiver. The study focused on the effect of signal attenuation due to weather conditions of the communication line connecting to the end-user of visible light system, also this paper examined the effect of reflectors on the weakly obtained signals from LED due to non-line of sight under different weather conditions such as rain and dust to obtain an satisfactory signal power at the end user. The system was simulated by Optisystem tool version 18 to support 1 Gbps, where it consists of one free space optic channel, 40 Km length of fiber optic, and a visible light system with one Light Emitting Diode, the reflector on the VLC system has been made with the help of Matlab simulation. The system was estimated based on the bit error rate, signal-to-noise ratio, and quality factor, BER of VLC achieved an adequate implementation in dusty weather to a distance of around 700 m, while, in rainy weather, the performance of the Q-factor was fair to a distance of 1800 m, comparison of BER and SNR under variation irradiance angle with using reflectors and without them have made, BER and SNR were staying stable around 1E-50 and 60 with using reflectors. A reflector was utilized to improve the system's implementation due to the diffusion of signal; thus, this reflector explained its capability to fix reflection. [ABSTRACT FROM AUTHOR]

Recent evidence suggests that mitochondrial complex II is an essential mediator of myocardial ischemia–reperfusion injury. The present study aimed to investigate the effects of fatty acid supplementation or high-fat diet (HFD) on cardiac mitochondrial activity. The changes of complex I and complex II activities and mitochondrial oxygen consumption rate (OCR) following hypoxia and re-oxygenation under these conditions were studied. Our results have shown that OCR (mitochondrial activity) was significantly increased with palmitoylcarnitine supplementation in mitochondria-enriched fraction from C57BL/6 mice hearts. Mitochondrial complex I activity was unaffected by palmitoylcarnitine but complex II activity was enhanced. Re-oxygenation following 30-min hypoxia transiently increased OCR but such an effect on OCR was abolished by complex II inhibitor, malonate, but not by complex I inhibitor, rotenone, despite that complex I activity was significantly increased with re-oxygenation following hypoxia in the presence of palmitoylcarnitine. Furthermore, OCR and complex II activity were significantly increased in the mitochondria from high-fat diet mice heart compared with those of normal or low-fat diet mice. Re-oxygenation to mitochondria following 30-min hypoxia increased OCR in all three groups but significantly more in HFD. Malonate abolished re-oxygenation-induced OCR increment in all groups. Our results indicate that complex II activity and OCR are enhanced with palmitoylcarnitine or in HFD mice heart. Although re-oxygenation following hypoxia enhanced complex II and complex I activities, complex II plays an important role in increasing mitochondrial activity, which may be instrumental in myocardial injury following ischemic reperfusion. [ABSTRACT FROM AUTHOR]