With the advent of the 5th generation of wireless standards and an increasing demand for higher throughput, methods to improve the spectral efficiency of wireless systems have become very important. In the context of cognitive radio, a substantial increase in throughput is possible if the secondary user can make smart decisions regarding which channel to sense and when or how often to sense. Here, we propose an algorithm to not only select a channel for data transmission but also to predict how long the channel will remain unoccupied so that the time spent on channel sensing can be minimized. Our algorithm learns in two stages -a reinforcement learning approach for channel selection and a Bayesian approach to determine the optimal duration for which sensing can be skipped. Comparisons with other learning methods are provided through extensive simulations. We show that the number of sensing is minimized with negligible increase in primary interference; this implies that lesser energy is spent by the secondary user in sensing and also higher throughput is achieved by saving on sensing.

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The classical anti‐inflammatory therapies are frequently ineffective and present numerous and severe side effects, especially in long term use, which requires the development of anti‐inflammatory drugs with different scaffolds and mechanisms of action. Owing to the high antioxidant potential and anti‐inflammatory activities already inferred for hydroxyflavones, we found it would be relevant to evaluate the anti‐inflammatory potential of a series of trihydroxyflavones by testing their ability to scavenge reactive oxygen species (ROS) and reactive nitrogen species (RNS) in cells and cell‐free systems and to inhibit the proinflammatory pathways mediated by the enzymes cyclooxygenase (COX) and 5‐lipoxygenase (5‐LOX), in which reactive species have a proven involvement. The tested trihydroxyflavones proved to be effective inhibitors of neutrophils' oxidative burst and were shown to scavenge different ROS and RNS in cell‐free systems. The most active compound in the majority of the assays was 3,3′,4′‐trihydroxyflavone, which was somehow expected due to the presence of the ortho‐dihydroxy in the B‐ring, an important structural feature in terms of free radical scavenging activity. Additionally, the studied compounds were able to inhibit the production of leukotriene B4 by 5‐LOX in activated neutrophils. 3,5,7‐Trihydroxyflavone was able to inhibit both COX‐1 and COX‐2, which makes it a dual inhibitor of COX and 5‐LOX pathways and, therefore, a promising candidate for a new therapeutic option in the treatment of inflammatory processes.