Risk Assessment Method Combining Independent Protection Layers (IPL) of Layer of Protection Analysis (LOPA) and RISKCURVES Software: Case Study of Hydrogen Refueling Stations in Urban Areas

The commercialization of eco-friendly hydrogen vehicles has elicited attempts to expand hydrogen refueling stations in urban areas; however, safety measures to reduce the risk of jet fires have not been established. The RISKCURVES software was used to evaluate the individual and societal risks of hydrogen refueling stations in urban areas, and the F–N (Frequency–Number of fatalities) curve was used to compare whether the safety measures satisfied international standards. From the results of the analysis, it was found that there is a risk of explosion in the expansion of hydrogen refueling stations in urban areas, and safety measures should be considered. To lower the risk of hydrogen refueling stations, this study applied the passive and active independent protection layers (IPLs) of LOPA (Layer of Protection Analysis) and confirmed that these measures significantly reduced societal risk as well as individual risk and met international standards. In particular, such measures could effectively reduce the impact of jet fire in dispensers and tube trailers that had a high risk. Measures employing both IPL types were efficient in meeting international standard criteria; however, passive IPLs were found to have a greater risk reduction effect than active IPLs. The combination of RISKCURVES and LOPA is an appropriate risk assessment method that can reduce work time and mitigate risks through protective measures compared to existing risk assessment methods. This method can be applied to risk assessment and risk mitigation not only for hydrogen facilities, but also for hazardous materials with high fire or explosion risk

Efficacy and Safety of <i>Lactobacillus Plantarum</i> C29-Fermented Soybean (DW2009) in Individuals with Mild Cognitive Impairment: A 12-Week, Multi-Center, Randomized, Double-Blind, Placebo-Controlled Clinical Trial

Early intervention using dietary supplements may be effective in alleviating cognitive impairment among individuals with mild cognitive impairment (MCI). This study investigated the efficacy and safety of Lactobacillus plantarum C29-fermented soybean (DW2009) as a nutritional supplement for cognitive enhancement. One hundred individuals with MCI were randomly assigned to take DW2009 (800 mg/day, n = 50) or placebo (800 mg/day, n = 50) for 12 weeks. The primary outcome measure was change in the composite score of cognitive functions related to memory and attention, measured by computerized neurocognitive function tests. Associations between changes in serum brain-derived neurotrophic factor (BDNF) levels and cognitive performance for each treatment group were evaluated. Compared to the placebo group, the DW2009 group showed greater improvements in the combined cognitive functions (z = 2.36, p for interaction = 0.02), especially in the attention domain (z = 2.34, p for interaction = 0.02). Cognitive improvement was associated with increased serum BDNF levels after consumption of DW2009 (t = 2.83, p = 0.007). The results of this clinical trial suggest that DW2009 can be safely administered to enhance cognitive function in individuals with MCI. Increased serum BDNF levels after administering DW2009 may provide preliminary insight into the underlying effects of cognitive improvement, which suggests the importance of the gut-brain axis in ameliorating cognitive deficits in MCI