• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.29 no.1
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• pp.14-27
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• 2024

Unlike the shelf sand ridges moribund in motion, nearshore sand ridges are highly mobile, sensitive to changes in ocean environments, thereby becoming of particular interest with respect to morphological changes. About 5 km off the Daesan port, the Jangan Sand Ridge has been undergoing severe subsea morphological change over the past two decades. Understanding the nature of sand ridges is critical to elucidate the causes of morphological changes. In this context, this study aims at understanding the characteristics and distribution patterns of surface sediments of the ridge and its vicinity. For this purpose, 227 sediment samples were acquired using a grab-sampler, the grain sizes being analysed by the sieve-pipette method. In addition, comparison of grain sizes in sediments between 1997 and 2021 was made in order to investigate the 25-years change in sediment composition. Surface sediments along the ridge axis are fine to medium sands with 2-3 phi in mean grain size, whereas, in the trough of ridge, the sediments are composed of gravels and muddy sandy gravels with mean sizes of -2 to -6 phi. Sediments in the crest of the ridge are well-sorted with normal distribution, on the other hand, the basal sediments are poorly-sorted and positively skewed. Along the ridge crest, the sediments are negatively skewed. From 1997 to 2021, the ridge sediments became largely coarser about 0.5 phi. Such coarsening trend in mean grain size can be explained either by elimination of fine sediments during high waves in winter or elimination of fines suspended during sand mining activities in the past. Spatial distribution pattern of surface sediments shows that ca. 30 m thick of the sand ridge itself overlies the thin relict gravels. The strong asymmetry of sand ridge, the exposure of ridge base, and reworked gravel lags suggest that Jangan sand ridge is probably sediment-deficit and hence erosive in nature at present.

• Journal of Dental Rehabilitation and Applied Science
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• v.40 no.2
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• pp.46-54
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• 2024

Purpose: The purpose of this study was to compare the periodontal status of end-stage renal disease patients undergoing dialysis and referred for intraoral evaluation prior to renal transplantation surgery with those having normal kidney function. Materials and Methods: Patients who had been undergoing dialysis for end-stage renal disease and been referred to the Dental Clinic Center by the Department of Nephrology at University Hospital for intraoral evaluation prior to kidney transplantation surgery. For comparison of periodontal status, subjects without abnormalities in kidney function were matched with the patients by age and gender and selected as healthy controls. The patients' age, gender, comorbidities, type of dialysis received, and duration of dialysis were investigated by reference to their medical records, and data on their periodontal status were analyzed via the relevant periodontal records. Results: A total of 102 patients, including 51 dialyzed patients and 51 healthy control group subjects, participated in this study. In the patients with end-stage renal disease undergoing dialysis with periodontal probing depth of 5 mm or more, percentage of sites with clinical attachment level of 4 mm or more, percentage of teeth with bleeding on probing, number of missing teeth, and ratio of moderate to severe periodontitis were all significantly greater than in the healthy controls. Conclusion: The periodontal status of end-stage renal disease patients undergoing dialysis and referred for intraoral evaluation prior to kidney transplantation was worse than that of healthy controls.

• IMMUNE NETWORK
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• v.24 no.2
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• pp.7.1-7.19
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• 2024

Viral load and the duration of viral shedding of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) are important determinants of the transmission of coronavirus disease 2019. In this study, we examined the effects of viral doses on the lung and spleen of K18-hACE2 transgenic mice by temporal histological and transcriptional analyses. Approximately, 1×10⁵ plaque-forming units (PFU) of SARS-CoV-2 induced strong host responses in the lungs from 2 days post inoculation (dpi) which did not recover until the mice died, whereas responses to the virus were obvious at 5 days, recovering to the basal state by 14 dpi at 1×10² PFU. Further, flow cytometry showed that number of CD8+ T cells continuously increased in 1×10² PFU-virus-infected lungs from 2 dpi, but not in 1×10⁵ PFU-virus-infected lungs. In spleens, responses to the virus were prominent from 2 dpi, and number of B cells was significantly decreased at 1×10⁵ PFU; however, 1×1² PFU of virus induced very weak responses from 2 dpi which recovered by 10 dpi. Although the defense responses returned to normal and the mice survived, lung histology showed evidence of fibrosis, suggesting sequelae of SARS-CoV-2 infection. Our findings indicate that specific effectors of the immune response in the lung and spleen were either increased or depleted in response to doses of SARS-CoV-2. This study demonstrated that the response of local and systemic immune effectors to a viral infection varies with viral dose, which either exacerbates the severity of the infection or accelerates its elimination.

• The Journal of Korean Society for School & Community Health Education
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• v.25 no.2
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• pp.27-44
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• 2024

Objectives: This study aimed to provide foundational data for preventing adolescents smoking by analyzing the relationship between adolescents' lifestyles and smoking experiences and identifying influencing factors. Methods: Secondary data analysis was conducted using the 17th (2021) Youth Health Behavior Survey data, encompassing 54,848 students from 796 schools. Variables included general characteristics, smoking status, lifestyle habits, physical activity, sleep patterns, and stress perception. Frequency analysis was used to examine general characteristics, while further analysis employed frequency analysis and the Pearson Chi-square test to compare lifestyle differences based on smoking presence. Multinomial logistic regression analysis was employed to determine factors influencing smoking experience, with IBM SPSS Statistics 28 used for all analyses at a significance level of p<.05. Results: Analysis revealed with general characteristics that the group with smoking experience exhibited a higher proportion of male students (67.4%) compared to the non-smoking group (50.1%) (p<.001). Analysis revealed that the smoking group was more likely to skip breakfast (27.7%), not consume fruit (17.8%), and consume fast food more than three times daily (0.9%). Furthermore, a higher percentage of smokers engaged in 60 minutes or more of breathless physical activity (8.4%) seven times a week, reported insufficient fatigue recovery through sleep (21.6%), and experienced very severe normal stress (17.2%) (p<.001). Analysis of the relationship between lifestyle and smoking indicated increased likelihood of smoking with zero breakfast consumption (OR=1.759, p<.001) and increased fruit consumption (OR=1.921, p<.001), while zero fast food consumption decreased smoking likelihood (OR=0.206, p<.001). Adequate sleep-related fatigue recovery reduced smoking likelihood (OR=0.458, p<.001), whereas increased stress elevated it (OR=1.260, p<.05). Conclusion: Adolescents' lifestyle habits significantly correlated with their smoking experiences, highlighting the necessity of considering lifestyle factors in smoking prevention strategies. This study provides crucial insights for promoting healthy lifestyle changes to prevent smoking among youth.

• Journal of Food Hygiene and Safety
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• v.39 no.1
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• pp.54-60
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• 2024

This study investigated the effectiveness of using pathogens and aqueous acids to reduce the Aspergillus ochraceus and Rhodotorula mucilaginosa contamination in livestock production environments. For this study, 1 mL of each bacterial suspension (10⁷-10⁸ spores/mL) was inoculated on a knife surface, dried at 37℃, and used under each treatment condition. First, to investigate the effect of organic acids, acetic, lactic, and citric acids were used. Subsequently, to select the appropriate concentration, they were prepared at concentrations of 0.5, 1, 2, 3, 4, and 5%, respectively. Accordingly, to further maximize the effect of organic acid treatment, we combined the treatment with ultraviolet light. The two strains showed a significant difference (P<0.05) compared to the initial strain, with a greater than 90% decrease in the concentrations of all organic acids. Consequently, acetic and lactic acids decreased by approximately 5 and 2 log colony forming unit (CFU)/cm², respectively, when treated with ultraviolet light (360 mJ/cm²); however, citric acid decreased by less than 1 log CFU/cm². However, when manufactured with 4% acetic acid, a severe malodor was emitted, making it difficult for workers to use it in a production environment. Accordingly, the optimal treatment conditions for organic acid and ultraviolet light for application were selected as follows: immersion in a 4% lactic acid solution for 1 minute and then, sterilization with ultraviolet light at 360 mJ/cm². Finally, when a pork meat sample was cut with a knife that was finally washed with lactic acid and treated with ultraviolet light, the low level of inoculum transferred from the cleaned knife to the surface of the sample was not detected. In conclusion, using this established method can prevent cross-contamination of the surface of the meat during processing.

• Journal of Industrial Convergence
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• v.22 no.2
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• pp.73-83
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• 2024

The purpose of this study is to diagnose various problems arising around social enterprises in the sport field from the perspective of the organization and derive necessary tasks and implications. In order to achieve the purpose of the study, the study was largely divided into three stages, and the results were derived. First, the main status and characteristics of social enterprises in the sport field were examined. The current status was analyzed focusing on aspects such as background and origin, legislation and policy, organizational goals, organizational structure and procedures, and organizational characteristics. Social enterprises in the sport sector were in their early stages, and the government's social enterprise policy goal tended to focus on increasing the number of social enterprises in a short period of time through financial input. In addition, it was found that most individual companies rely on government subsidy support due to insufficient profit generation capacity. In the second stage, we focused on the situational factors that affect the functional performance of social enterprises in the sport field. As a result of reviewing the value, ideology, technology, and history of the organization, which are situational factors, it was derived that when certified as a social enterprise in the sport field and supported by the central government or local governments, political control is strong to some extent and exposure to the market is not severe. In the last third step, tasks and implications were derived to form an appropriate organization for social enterprises in the sport field. After the social enterprise ecosystem in the sport sector has been established to some extent, it is necessary to gradually move from the current "government-type" organization to the "national enterprise" organization. This is true in light of the government's limited financial level, not in the short term, but in order for the organization of social enterprises in the sports sector to survive in the long term.

• Pediatric Infection and Vaccine
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• v.31 no.1
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• pp.12-24
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• 2024

The number of pediatric coronavirus disease 2019 (COVID-19) cases worldwide are increasing compared to the early phase of the pandemic, along with highly transmissible severe acute respiratory syndrome coronavirus variant and the increase in adult COVID-19 vaccination. We conducted a rapid systematic review and meta-analysis of published randomized clinical trials (RCTs) of the COVID-19 vaccines and the observational retrospective studies on adverse events after COVID-19 vaccination in adolescents. Seventeen studies were finally included in this systematic review. Meta-analysis showed that although vaccination in adolescents was significantly effective to prevent COVID-19 infection in retrospective studies (risk ratio [RR], 0.29; 95% confidence interval [CI], 0.22-0.37; I² =100%), however the effect of preventing COVID-19 infection was lower than in RCTs (RR, 0.05; 95% CI, 0.01-0.27). In five retrospective studies, the pooled estimated proportion of participants with myocarditis and/or pericarditis was 2.33 per 100,000 of the population (95% CI, 0.97-5.61 per 100,000). Sub-group analysis with sex and vaccine doses showed that male (5.35 per 100,000) and the second dose (9.71 per 100,000) had significantly higher incidence of myocarditis and/or pericarditis than female (1.09 per 100,000) and the first dose (1.61 per 100,000), respectively. Our study showed that mRNA COVID-19 vaccines in adolescent recipients were favorable and effective against COVID-19 in RCT as well as observational studies. The safety findings of BNT162b2 vaccine in adolescents were explored and we found the difference of safety according to sex and vaccine doses. The occurrence of adverse events after mRNA COVID-19 vaccination should be monitored.

• Health Policy and Management
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• v.34 no.2
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• pp.129-140
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• 2024

Background: The mental health issues caused by trauma can manifest differently depending on the characteristics of the traumatic event. Particularly, individuals who have experienced sexual trauma are known to have more negative mental health outcomes compared to those who have experienced non-sexual trauma. The mental health issues of individuals who have experienced sexual trauma are severe, and new forms of threats, such as digital sexual crimes, are emerging. This study aimed to investigate whether the type of traumatic event, particularly focusing on sexual trauma events, contributes to differences in mental health outcomes and to identify factors influencing suicidal ideation and potential post-traumatic stress disorder (PTSD) risk. Methods: Based on an online survey conducted nationwide among adults aged 20 to 50, participants were categorized based on the type of trauma they experienced (sexual trauma events and non-sexual trauma events). The study conducted propensity score matching (PSM) using demographic factors (sex, age group, subjective economic status, and marital status) and resilience protective factors (cognition of recoverability, social support, and protection experiences in childhood) as control variables, excluding the experience of sexual trauma events, to investigate their potential impact on mental health (suicidal ideation and potential PTSD risk). Subsequently, binary logistic regression analysis was conducted to identify factors influencing mental health. Results: Even after PSM, individuals who experienced sexual trauma exhibited more negative outcomes in terms of suicidal ideation and potential PTSD risk compared to those who experienced non-sexual trauma. The results of binary logistic regression analysis showed that sexual trauma survivors were 1.9 times more likely to have suicidal thoughts (odds ratio [OR], 1.911) and 2.5 times more likely to have a potential PTSD risk (OR, 2.472). Furthermore, as resilience protective factors became more negative, the likelihood of suicidal ideation and potential PTSD risk increased. Conclusion: This study emphasizes the importance of understanding and supporting individuals who have experienced sexual trauma, highlighting the necessity for strategies aimed at mitigating suicidal ideation and potential PTSD risk among sexual trauma survivors, while also facilitating recovery through the promotion of resilience protective factors.

• Health Policy and Management
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• v.34 no.2
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• pp.185-195
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• 2024

Background: Disabled people have particularly restricted access to health care. In response to this, the pilot project for the general physician (GP) system for disabled people was implemented in 2018, based on the rights of people with disability to the Health Act in South Korea. However, its participants were 0.2% among the total of those with severe disabilities in 2021. Therefore, this study examined the factors related to registering with a GP and the access level to its services to suggest implications for activating the participation of disabled people. Methods: We analyzed factors affecting the registration with a GP and the number of using the services among the participants of the GP system during May 2018 and December 2021 by conducting hierarchical logistic regression and hierarchical regression. The data were linked with the national health insurance data to examine various predictors, including disability types, socioeconomic status, health status, and GP registration. Results: As a result of analyzing the factors affecting whether or not to register for the pilot project, those with disabilities (physical disabilities, brain lesions, visual, intellectual, mental, and autistic disability) eligible for disability care (odds ratio [OR], 4.157) than other disability, and those living in metropolitan (OR, 4.330) or cities (OR, 3.332) than rural residences were highly likely to enroll the pilot study. Health-related variables also predicted the registration status of the pilot project. The predictors related to GP enrollment types (membership type: general health or disability care, GP's affiliation: clinics or hospitals) significantly influenced levels of access to services. Conclusion: It is necessary to develop the GP project for disabled people by considering the variation in types of disability, residences, and health. Further study will be needed to investigate the impact of GPs on the level of participation among disabled people.

• Korean Journal of Heritage: History & Science
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• v.57 no.2
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• pp.118-141
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• 2024

This study investigates and analyzes ancient literature records and iconographic materials to examine the Willow Tree Fence(樹柵) built on Gasan(假山) Cheonggyecheon(淸溪川) within the Hanyangdoseong, which was deliberately created to prevent flood damage during the Joseon Dynasty. Although there have been research cases related to the willow tree, it is difficult to find research conducted with the purpose of identifying its archetypal value by investigating and analyzing specific use cases of the willow tree and its historical background. Accordingly, this study aims to identify examples of the Willow Tree Fence(樹柵) created in Cheonggyecheon(淸溪川) during the Joseon Dynasty and reinterpret their value by illuminating the background of construction and regional characteristics. The main contents of this study are as follows. It is presumed that floods during the Joseon Dynasty were a great hazard. Between the 16th and 18th centuries, Joseon suffered severe damage from floods. By the time of King Yeongjo, all Four Mountains(四山) of the capital had become bare mountains, which was the cause of frequent floods. In the year of Gyeongjin(庚辰, the 26th year of King Yeongjo's reign, 1760), King Yeongjo dredged the channel bottom of Cheonggyecheon(淸溪川), which overflowed every rainy season, with the Juncheon Project(Channel-Dredging, 濬川事業) and planted willow trees on the mountain on both sides of the Ogan Water Gate(五間水門), as measures to prevent flood damage and soil loss. was implemented. In the <Doseongdo(都城圖)> in 《 Gwangyeodo(廣輿圖)》 produced in the mid-18th century during the reign of King Yeongjo, Gasan(假山), built in front of the Ogan Water Gate(五間水門) is visible, and in the record 『Sinjeung Donggukyeoji Seungnam(新增東國輿地勝)』 In the record, it appears that willows were planted on both sides of the mountain in the year of Gyeongjin(1760). With <Hanyangdoseong Map(漢陽都城圖)> produced in the 46th year of King Yeongjo's reign(1770), it is confirmed that willow trees formed a thick forest on Gasan Mountain near the Ogan Water Gate(五間水門) in the late 18th century. In addition, the Juncheon Project(Channel-Dredging, 濬川事業) and the creation of the Willow Tree Fence(樹柵) continued from the 15th century, the early Joseon Dynasty(朝鮮前期), to the end of the 19th century, the late Joseon Dynasty(朝鮮後期), through the records of ancient literature such as 『Annals of the Joseon Dynasty(朝鮮王朝實錄)』, 『Seungjeongwon Diary(承政院日記)』, and 『Records of Daily Reflections(日省錄)』. This study is meaningful in informing that the willow tree was a unique cultural heritage and traditional landscape resource by investigating the composition and use of the Willow Tree Fence in the Joseon Dynasty, which was a great basis for preventing floods and flood damage, as well as forming a beautiful landscape.