• Journal of the Korean Wood Science and Technology
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• v.52 no.2
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• pp.145-156
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• 2024

Unlike resistant cells, persister cells resist antibiotics due to a decreased cellular metabolic rate and can transition back to normal susceptible cells when the antibiotic is removed. These persister cells contribute to the chronic symptoms of infectious diseases and promote the emergence of resistant strains with continuous antibiotic exposure. Therefore, eliminating persister cells represents a promising approach to significantly enhance antibiotic efficacy. Here, we found that Coicis Semen extract reduced Staphylococcus aureus persister cells at a concentration of 0.5 g/L. Linoleic acid and oleic acid, the major components of Coicis Semen extract, exhibited a comparable reduction in persister cells when combined with three antibiotics: ciprofloxacin, oxacillin, and tobramycin. Conversely, these effects were nullified in the presence of the surfactant Tween 80 (1%), suggesting that the hydrophobic characteristics of linoleic acid and oleic acids play a pivotal role in reducing the number of S. aureus persister cells. Considering the concentration-dependent effects of linoleic acid and oleic acid, the persister-reducing activity of Coicis Semen extract was primarily attributed to these fatty acids. Moreover, Coicis Semen extract, linoleic acid, and oleic acid increased the cell membrane permeability of S. aureus. Interestingly, this effect was counteracted by 1% Tween 80, indicating a close association between the reduction of persister cells and the increase in cell membrane permeability. The identified compounds could thus be used to eliminate persister cells, thereby enhancing therapeutic efficacy and shortening treatment duration. When used in conjunction with antibiotics, they may also mitigate chronic symptoms and significantly reduce the emergence of antibiotic-resistant bacteria.

• Korean Journal of Construction Engineering and Management
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• v.25 no.2
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• pp.36-44
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• 2024

This paper presents the application of Convolutional Neural Networks (CNNs) and Region of Interest (ROI) techniques for concrete crack analysis. Surfaces of concrete structures, such as beams, etc., are exposed to fatigue stress and cyclic loads, typically resulting in the initiation of cracks at a microscopic level on the structure's surface. Early detection enables preventative measures to mitigate potential damage and failures. Conventional manual inspections often yield subpar results, especially for large-scale infrastructure where access is challenging and detecting cracks can be difficult. This paper presents data collection, edge segmentation and ROI techniques application, and analysis of concrete cracks using Convolutional Neural Networks. This paper aims to achieve the following objectives: Firstly, achieving improved accuracy in crack detection using image-based technology compared to traditional manual inspection methods. Secondly, developing an algorithm that utilizes enhanced Sobel edge segmentation and ROI techniques. The algorithm provides automated crack detection capabilities for non-destructive testing.

• Journal of Advanced Technology Convergence
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• v.3 no.1
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• pp.43-49
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• 2024

The beauty industry has evolved into a highly competitive service sector, expanding alongside economic growth. Nail art, in particular, has witnessed a remarkable surge in popularity. To efficiently manage individual time, nail salons have adopted reservation systems. However, the issue of no-shows, where customers fail to keep their appointments, has emerged as a significant societal and economic concern. This study seeks to identify and address the root causes of no-shows in nail salons, providing essential data for the industry. A comprehensive survey was conducted, involving 476 customers from nail salons in the Daejeon and Chungcheong regions. Survey responses were analyzed using SPSS 24.0 software. Results revealed that a change of mind was the primary reason for no-shows. This underscores the importance of promoting reservation awareness among both businesses and consumers. To mitigate no-shows, suggestions included implementing non-refundable reservation deposits and imposing cancellation fees. Notably, the beauty industry currently lacks systematic regulations concerning no-shows, highlighting the necessity for future research aimed at developing reservation-related guidelines and standards.

• Korean Journal of Community Nutrition
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• v.29 no.2
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• pp.114-128
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• 2024

Objectives: The purpose of this study was to investigate the perception of nutrition teachers and the factors influencing their intention toward sustainable dietary education utilizing the theory of planned behavior (TPB). Methods: The self-administered online survey was completed by nutrition teachers in Jeollanam-do, South Korea. A total of 151 valid questionnaires were analyzed. Factor analysis and multiple regressions were employed to test the research model. Results: The study findings demonstrated that all TPB variables significantly influenced the sustainable dietary educational intention, with the degree of influence ranking as follows: external perceived behavioral control (β = 0.417), attitude (β = 0.240), internal perceived behavioral control (β = 0.207), and subjective norms (β = 0.181). For external perceived behavioral control, nutrition teachers and elementary schools exhibited higher levels compared to dietitians and middle/high schools, respectively. The participants in sustainable dietary education training programs exhibited a higher level of internal perceived behavioral control compared to those who did not participate. The highest perception levels were reported for attitude (4.26), followed by subjective norms (4.02), internal perceived behavioral control (3.67), and external perceived behavioral control (3.20). Conclusions: This study affirmed that the TPB variables elucidated the sustainable dietary educational intentions of nutrition teachers. The significant impacts of external and internal perceived behavioral control, attitude, and subjective norms on educational intentions were confirmed. Consequently, proactive support from schools and governments is essential to enhance the facilitating factors and mitigate the barriers toward sustainable dietary education in schools.

• Korean Journal of Community Nutrition
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• v.29 no.2
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• pp.156-170
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• 2024

Objectives: This study aimed to investigate the association between how often Korean adolescents watch Mukbang and Cookbang videos and their dietary habits. Methods: Data from the 18th Korea Youth Risk Behavior Survey conducted in 2022 was analyzed for this study. The study included 51,850 middle and high school students and assessed various aspects, including demographics, frequency of watching Mukbang and Cookbang videos per week, dietary habits, health behaviors, and mental health factors. Results: Nearly a third (29.3%) of Korean adolescents watched Mukbang and Cookbang videos one to four times a week, while 13.5% watched them more than five times weekly. Females, those with lower academic achievement, and those from lower socioeconomic backgrounds were significantly more likely to be frequent viewers (P < 0.001). Increased viewing frequency was associated with poorer dietary habits. Adolescents who watched more frequently were less likely to eat breakfast and consume fruits and milk, while their consumption of fast food, high-caffeine drinks, sugary drinks, and late-night snacks increased (P < 0.001). Higher viewing frequency correlated with increased feelings of stress, depression, and loneliness (P < 0.001). Logistic regression analysis confirmed these associations. More frequent viewers were significantly less likely to eat breakfast (odds ratio (OR), 0.63; 95% confidence interval (CI), 0.58-0.68), and more likely to consume fast food (OR, 1.85; 95% CI, 1.69-2.02), high-caffeine drinks (OR, 1.43; 95% CI, 1.30-1.56), sugary drinks (OR, 1.54; 95% CI, 1.41-1.67), and late-night snacks (OR, 1.37; 95% CI, 1.25-1.51). Conclusions: Our findings suggest that frequent exposure to Mukbang and Cookbang content is linked to unhealthy dietary habits in adolescents. Educational programs may be necessary to mitigate the potential for these videos to negatively influence dietary choices.

• Fisheries and Aquatic Sciences
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• v.26 no.12
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• pp.715-725
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• 2023

Microplastic (MP) pollution in aquatic environments is a growing concern worldwide. This study investigated the abundance, types, and attributes of MPs in the surface water at two industrial sites (Avoimitro Ghat and Kalurghat) along the Karnaphuli River in Chattogram, Bangladesh. Sampling was conducted over eight months across three transects encompassing a total area of 500 m at each site. A manta net of 200 ㎛ mesh size was used to sample MPs. The obtained samples were subsequently filtered, enumerated, and characterized using a stereo microscope and imaging software. The mean abundance of MP particles (per km² ) was found higher in Avoimitro Ghat (94,861 ± 57,126) than in Kalurghat (31,343 ± 23,183). A significant statistical difference (p < 0.05) was observed in the mean abundance of MP particles between the wet and dry seasons. The fragment group of MP exhibited the most abundant category, whereas the pellet category displayed the lowest. MPs with an elongated shape prevailed at both locations throughout all seasons. At Avoimitro Ghat, blue-colored MPs demonstrated the highest mean count, while in Kalurghat, the highest mean count belonged to brown-colored MPs. The size distribution of MPs differed between the two sites, with 1-2 mm MPs being plentiful in both seasons and Avoimitro Ghat, whereas MPs ranging from 500 ㎛ to less than 1 mm were abundant in Kalurghat. Ten (10) polymer types were found from Fourier-transform infrared spectroscopy (FTIR) analysis with high levels of polypropylene atactic in both Avoimitro Ghat (32%) and Kalurghat (17%). The findings provide important insights into MP pollution in the Karnaphuli River, which may aid in developing effective strategies to mitigate the impacts of MP pollution on the aquatic ecosystem and human health.

• Safety and Health at Work
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• v.14 no.4
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• pp.467-475
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• 2023

Background: To mitigate the spread of Covid-19, nurses infected with the virus were required to isolate themselves from their families and community. Isolated patients were reported to have experienced mental distress, posttraumatic stress disorder symptoms, and suicide. Though studies have reported the psychological impact of the Covid-19 pandemic, less is known about the lived experiences of nurses who survived Covid-19 infection in sub-Saharan Africa. Methods: A descriptive phenomenological approach was used to study the lived experiences of registered nurses who survived Covid-19 disease. In-depth interviews were conducted among nurses diagnosed with Covid-19 from two hospitals in Kenya between March and May, 2021. Purposive and snowball sampling were used to recruit registered nurses. Data were analyzed using Giorgi's steps of analysis. Results: The study included ten nurses between 29 and 45 years of age. Nurses' experiences encompassed three themes: diagnosis reaction, consequences, and coping. Reactions to the diagnosis included fear, anxiety, and sadness. The consequence of the diagnosis and isolation was stigma, isolation, and loneliness. Nurses coping mechanisms included acceptance, creating routines, support, and spirituality. Conclusion: Our findings aid in understanding how nurses experienced Covid-19 infection as patients and will provide evidence-based content for supporting nurses in future pandemics. Moreover, as we acknowledge the heroic contribution of frontline healthcare workers during the Covid-19 pandemic, it is prudent to recognize the considerable occupational risk as they balance their duty to care, and the risk of infection to themselves and their families.

• The Plant Pathology Journal
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• v.40 no.2
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• pp.106-114
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• 2024

Fusarium head blight (FHB), predominantly caused by Fusarium graminearum and F. asiaticum, is a significant fungal disease impacting small-grain cereals. The absence of highly resistant cultivars underscores the need for vigilant FHB surveillance to mitigate its detrimental effects. In 2023, a notable FHB outbreak occurred in the southern region of Korea. We assessed FHB disease severity by quantifying infected spikelets and grains. Isolating fungal pathogens from infected samples often encounters interference from various microorganisms. We developed a cost-effective, selective medium, named BGT (Burkholderia glumae Toxoflavin) medium, utilizing B. glumae, which is primarily known for causing bacterial panicle blight in rice. This medium exhibited selective growth properties, predominantly supporting Fusarium spp., while substantially inhibiting the growth of other fungi. Using the BGT medium, we isolated F. graminearum and F. asiaticum from infected wheat and barley samples across Korea. To further streamline the process, we used a direct PCR approach to amplify the translation elongation factor 1-α (TEF-1α) region without a separate genomic DNA extraction step. Phylogenetic analysis of the TEF-1α region revealed that the majority of the isolates were identified as F. asiaticum. Our results demonstrate that BGT medium is an effective tool for FHB diagnosis and Fusarium strain isolation.

• Computers and Concrete
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• v.33 no.4
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• pp.425-443
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• 2024

Floods are among the most common natural hazards in urban areas. To mitigate the problems caused by flooding, unstructured data such as images and videos collected from closed circuit televisions (CCTVs) or unmanned aerial vehicles (UAVs) have been examined for flood management (FM). Many computer vision (CV) techniques have been widely adopted to analyze imagery data. Although some papers have reviewed recent CV approaches that utilize UAV images or remote sensing data, less effort has been devoted to studies that have focused on CCTV data. In addition, few studies have distinguished between the main research objectives of CV techniques (e.g., flood depth and flooded area) for a comprehensive understanding of the current status and trends of CV applications for each FM research topic. Thus, this paper provides a comprehensive review of the literature that proposes CV techniques for aspects of FM using ground camera (e.g., CCTV) data. Research topics are classified into four categories: flood depth, flood detection, flooded area, and surface water velocity. These application areas are subdivided into three types: urban, river and stream, and experimental. The adopted CV techniques are summarized for each research topic and application area. The primary goal of this review is to provide guidance for researchers who plan to design a CV model for specific purposes such as flood-depth estimation. Researchers should be able to draw on this review to construct an appropriate CV model for any FM purpose.

• Geophysics and Geophysical Exploration
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• v.27 no.2
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• pp.129-143
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• 2024

In magnetotelluric (MT) surveys, small inhomogeneities near the surface cause a static shift in which apparent resistivities shift regardless of frequency. As the static shift in MT data leads to errors in subsurface structure interpretation, many studies have been conducted over the past few decades to mitigate or remove the distortions it caused. The most representative method involves removing static shifts from the data before inversion. Conversely, static shifts can be corrected during inversion or included in the inversion process. In addition, other geophysical data can be used to remove static shifts. However, the correction methods are limited to one-dimensional (1D) static responses, and limitations remain in two- or three-dimensional (2D or 3D) interpretation of distorted MT data owing to static shifts. This study provides a foundation for future studies on static shift by analyzing several previously published methods.