Deep Multi-Agent Reinforcement Learning using DNN-Weight Evolution to Optimize Supply Chain Performance

To develop a supply chain management (SCM) system that performs optimally for both each entity in the chain and the entire chain, a multi-agent reinforcement learning (MARL) technique has been developed. To solve two problems of the MARL for SCM (building a Markov decision processes for a supply chain and avoiding learning stagnation in a way similar to the prisoner\u27s dilemma ), a learning management method with deep-neural-network (DNN)-weight evolution (LM-DWE) has been developed. By using a beer distribution game (BDG) as an example of a supply chain, experiments with a four-agent system were performed. Consequently, the LM-DWE successfully solved the above two problems and achieved 80.0% lower total cost than expert players of the BDG

Ancient Evolutionary History of Human Papillomavirus Type 16, 18 and 58 Variants Prevalent Exclusively in Japan

Human papillomavirus (HPV) is a sexually transmitted virus with an approximately 8-kilo base DNA genome, which establishes long-term persistent infection in anogenital tissues. High levels of genetic variations, including viral genotypes and intra-type variants, have been described for HPV genomes, together with geographical differences in the distribution of genotypes and variants. Here, by employing a maximum likelihood method, we performed phylogenetic analyses of the complete genome sequences of HPV16, HPV18 and HPV58 available from GenBank (n = 627, 146 and 157, respectively). We found several characteristic clusters that exclusively contain HPV genomes from Japan: two for HPV16 (sublineages A4 and A5), one for HPV18 (sublineage A1) and two for HPV58 (sublineages A1 and A2). Bayesian phylogenetic analyses of concatenated viral gene sequences showed that divergence of the most recent common ancestor of these Japan-specific clades was estimated to have occurred ~98,000 years before present (YBP) for HPV16 A4, ~39,000 YBP for HPV16 A5, ~38,000 YBP for HPV18 A1, ~26,000 for HPV58 A1 and ~25,000 YBP for HPV58 A2. This estimated timeframe for the divergence of the Japan-specific clades suggests that the introduction of these HPV variants into the Japanese archipelago dates back to at least ~25,000 YBP and provides a scenario of virus co-migration with ancestral Japanese populations from continental Asia during the Upper Paleolithic period