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Attentional bias to threat has been almost exclusively examined after participants experienced repeated pairings between a conditioned stimulus (CS) and an aversive unconditioned stimulus (US). This study aimed to determine whether threat-related attentional capture can result from observational learning, when participants acquire knowledge of the aversive qualities of a stimulus without themselves experiencing aversive outcomes. Non-clinical young-adult participants (N = 38) first watched a video of an individual (the demonstrator) performing a Pavlovian conditioning task in which one colour was paired with shock (CS+) and another colour was neutral (CS−). They then carried out visual search for a shape-defined target. Oculomotor measures evidenced an attentional bias toward the CS+ colour, suggesting that threat-related attentional capture can ensue from observational learning. Exploratory analyses also revealed that this effect was positively correlated with empathy for the demonstrator. Our findings extend empirical and theoretical knowledge about threat-driven attention and provide valuable insights to better understand the formation of anxiety disorders. [ABSTRACT FROM AUTHOR]

Every year more than 100 fatal accidents occur in road work zones. One of the major causes of pedestrian workers being struck by construction vehicles is that workers become habituated to the warning alarms of these vehicles. Researchers suggest that workers with certain personality traits (e.g., boredom proneness and extraversion) are more likely to become habituated to workplace hazards and therefore have a higher likelihood than other workers of being involved in an accident. This study investigated which aspects of personality correlate with workers' accident proneness and their vulnerability to habituation to warning alarms in road work zones. An experiment with actual road construction workers was performed using a virtual reality (VR) environment. The results reveal that boredom susceptibility (one of the subdimensions of the personality trait of sensation seeking) is negatively correlated with workers' attention to warning alarms, and that boredom-prone workers were more likely to be involved in a virtual struck-by accident. The findings of this study provide conceptual motivation for tailoring safety training to individual workers' personality traits. [ABSTRACT FROM AUTHOR]

Repeated exposure to hazards in road construction work zones often generates worker habituation to risks associated with those hazards, a key causal factor in workplace accidents. Understanding the developmental process of risk habituation and providing effective intervention are thus critical to preventing fatalities in road construction work zones. To this end, this study investigates the efficacy of virtual reality (VR) as a behavioral intervention tool to mitigate a decline in vigilant behaviors with habituation to workplace hazards. A VR environment that simulates road construction/maintenance tasks was created and used to repeatedly expose participants to struck-by hazards in road construction operations. An accident was simulated upon the emergence of inattentiveness to hazards within the VR environment. The sustained intervention effect was examined using pretest-posttest analyses to compare the frequency and threshold of participants' vigilant behaviors. The results revealed that the VR environment elicited a reduction in attentiveness associated with risk habituation over a relatively short period of time, and the simulated accidents in the VR environment generated sustained impacts in the mitigating of the effects of habituation on attention over a week's time interval. The outcomes of this study contribute to the understanding of how workers' risk habituation can be measured in a VR environment and provide new knowledge regarding how a VR-based behavioral intervention can mitigate the attentional consequences of habituation to repeatedly exposed workplace hazards. [ABSTRACT FROM AUTHOR]

Ulleung-do is a volcanic island located 130 km east of the Gangwon-do province of South Korea. It is characterized by steep slopes covered with effusive rocks released from multiple volcanic activities. Having accumulated deep colluvium, Ulleung-do Island manifests a high vulnerability to landslides frequently caused by heavy rains or typhoons, debris flow, rockfall, and other disaster hazards in mountainous areas. Therefore, facilities and residential areas located in the lower areas of the island sustain widespread damage. Hence, the installation of check dams designed to reflect the area's local conditions is required to avoid further damage. In line with that, this study analyzes the disaster cases in Ulleung-do's mountain areas and the effect of check dams in debris flow reduction for each type using the KANAKO-2D model. At observation point 1, the result shows that the maximum rate of debris flow is reduced by 48.5% with an open-type check dam installed and 62.9% with a closed-type check dam installed from the level without a check dam. For observation point 2, the maximum flow depth decreases by 49.7% with an open-type check dam and 77.4% with a closed-type check dam. Thus, this study suggests that the simple installation of check dams in a mountain stream that has experienced debris flow effectively mitigates damage brought by various disasters. [ABSTRACT FROM AUTHOR]

Abstract A sabo dam has a purpose to block the path of debris flow. However, when overflow occurs, a sabo dam works as a weir, a vertical obstruction, where the fluid must flow over. Many empirical formulas and discharge coefficients for weirs relating flow depth to discharge have been proposed to calculate overflow discharges. However, only a few studies about overflow discharge coefficients are available in the case of debris flow. In this paper, experiments and numerical simulations were done to estimate debris flow discharge coefficients by considering the sediment concentration. In the numerical simulation, a complete overflow equation and a free overfall equation were implemented to calculate debris overflow discharges at a sabo dam. To determine the discharge coefficients for each equation, single factor regression analysis was used. Laboratory experiments were done to calibrate and to compare with the simulation. Study results showed that the discharge coefficients increase as the sediment concentration increases. This finding suggests debris flow discharge coefficients are derived to calculate the debris overflow discharges at a sabo dam. [ABSTRACT FROM AUTHOR]

Semi‐interpenetrating polymer networks (semi‐IPNs) composed of chitosan and polyacrylamide (PAAm) hydrogels have been prepared, and the effect of changing pH, temperature, ionic concentration, and applied electric fields on the swelling of the hydrogels was investigated. The swelling kinetics increased rapidly, reaching equilibrium within 60 min. The semi‐IPN hydrogels exhibited a relatively high swelling ratios of 385%–569% at T=25°C. The swelling ratio increased with decreasing pH below pH=7 due to the dissociation of ionic bonds. The swelling ratio of the semi‐IPN hydrogels was pH, ionic concentration, temperature, and electric field dependent. Differential scanning calorimetry (DSC) was used to determine the volume of free water in the semi‐IPN hydrogels, which was found to increase with increasing PAAm content. [ABSTRACT FROM AUTHOR]

A temperature- and pH-responsive interpenetrating polymer network (IPN) hydrogels constructed with polymethacrylic acid (PMAAc) and sodium alginate (SA) by sequential IPN method was studied. The characterizations of IPN hydrogels were investigated by fourier transform infra-red spectroscopy (FT-IR), differential scanning calorimetry (DSC) and swelling tests under various conditions. IPN hydrogels exhibited a relatively high swelling ratio in the range of 183-916% at 25°C. The swelling ratio of PMAAc/SA IPN hydrogels depended on pH, temperature and ionic concentration. DSC was used for the quantitative determination of the amounts of freezing and non-freezing water. The amount of free water increased with increasing PMAAc content in the IPN hydrogels. [ABSTRACT FROM AUTHOR]

Habituation to signals that warn of a potential danger in high-risk work environments is a critical causal factor of workplace accidents. Such habituation is hard to measure in a real-world setting, and no existing intervention can effectively curb it. Here, we present a protocol to enhance workers' sensory responses to frequently encountered warnings at workplaces using a virtual-reality-based behavioral intervention. We describe steps for performing a virtual reality experiment and an electroencephalography (EEG) experiment with human participants. For complete details on the use and execution of this protocol, please refer to Kim et al. 1 ., Competing Interests: Declaration of interests The authors declare no competing interests., (Copyright © 2024 The Authors. Published by Elsevier Inc. All rights reserved.)

In high-risk work environments, workers become habituated to hazards they frequently encounter, subsequently underestimating risk and engaging in unsafe behaviors. This phenomenon has been termed "risk habituation" and identified as a vital root cause of fatalities and injuries at workplaces. Providing an effective intervention that curbs workers' risk habituation is critical in preventing occupational injuries and fatalities. However, there exists no empirically supported intervention for curbing risk habituation. To this end, here we investigated how experiencing an accident in a virtual reality (VR) environment affects workers' risk habituation toward repeatedly exposed workplace hazards. We examined an underlying mechanism of risk habituation at the sensory level and evaluated the effect of the accident intervention through electroencephalography (EEG). The results of pre- and posttreatment analyses indicate experiencing the virtual accident effectively curbs risk habituation at both the behavioral and sensory level. The findings open new vistas for occupational safety training., Competing Interests: The authors declare no competing interests., (© 2022 The Author(s).)