旭硝子財団助成研究成果報告2022

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93Teeraphan LAOMETTACHIT94Uday PIMPLE95Vitoon UTHAISANGSUKNano-TiO2 Hepatotoxic Response Mediated by Intracellular Signaling Pathways: A System-Level Investigation(Project 2019)Development Automated Mangrove Forest Monitoring System Characterized by Physiological Effect of Environmental Factors(Project 2019)Material Design and Characterisation for Laser Heat Treating and Welding Process Using a Multi-Scale Approach(Project 2020)70旭硝子財団　助成研究成果報告（2022）TiO2 nanoparticles (NPs) have found extensive food and daily products applications. Sufficient evidence in the literature has shown that TiO2 NPs may cause harmful effects to many organs in animal studies. However, little is known about the toxicity of the NPs in humans. In the current work, we propose a computational framework that integrates our previous physiologically-based pharmacokinetic (PBPK) model with a newly developed intracellular signaling model of the liver tissue upon TiO2 NP exposure. The integrated framework is used to simulate and assess hepatotoxicity in humans orally exposed to the NPs with a dose corresponding to an estimate from daily food consumption. Our computational study suggests that the toxicity of TiO2 NPs to the liver based on the current daily consumption amount is not negligible, and our predictions prompt further experimental investigation to limit the allowed amount of the NPs used in everyday products.The United Nations Decade on Ecosystem Restoration lists mangrove forests, as a restoration priority; however various climate change factors including sea-level rise, altered precipitation, and increasing temperature are impacting mangroves at various scales. However, information on how the natural and rehabilitated mangrove forests change physiological function in relation to changing climate is scant. The objective of the proposed study is to develop an automated monitoring system characterized by the physiological effects of several environmental factors. The developed monitoring station is mounted on a 21 m self-supporting tower. The monitoring station consists of the ATMOS-41 All-in-One weather system, spectral reflectance (NDVI and PRI), and HYDROS-21 to measure the environmental conditions including temperature, humidity, precipitation, photosynthetic activities, and tidal parameters. This data will give deeper insights into the dynamics of photosynthesis, fruiting and flowering phenology, and changing environmental conditions. Also, will support remote sensing and modeling approaches at a larger spatial scale.Progresses in fusion joining between aluminum alloy with steel were limited due to its complex metallurgical reactions between liquid steel and aluminum. This work provided an insight into effects of homogeneous and inhomogeneous fusion zone of laser welded steel-aluminum joints. Detailed metallographic and chemical composition analyses of the fusion zone were firstly presented and discussed. An indentation reverse method was developed for predicting local stress-strain behaviors of the fusion zones. Then, FE simulations of lap shear test for laser welded steel-aluminum joint were performed, in which individual properties of the weld zone were given. The cohesive zone model (CZM) based on maximum strength was applied for representing local damage evolution of intermetallic layer along the interface in welded samples. Cross tension and double cantilever beam (DCB) tests were conducted for determining mode I bonding strength and fracture energy of the CZM. The peak forces of welded steel-aluminum joint samples using different welding speeds were predicted. The numerical results showed satisfactory agreement with experimentally obtained