Porcine edema disease (ED) is an enterotoxemia of pigs caused by Escherichia coli that produces Stx2e. In this study, the protective efficacy of a recombinant modified Stx2e toxoid was evaluated as a vaccine candidate against ED in piglets. The recombinant Stx2e toxoid was expressed and purified using a commercial E. coli expression system. A total of 25 piglets were used and divided into 5 groups (A to E), with 5 piglets in each group. All piglets (except those in group A) were intramuscularly immunized at 5 days of age (0 weeks post prime immunization; 0 WPPI) and again at 3 weeks of age (2 WPPI). Group B piglets were inoculated with sterile PBS, while groups C to E were immunized with 25 μg/piglet, 50 μg/piglet, and 100 μg/piglet of the recombinant toxoid, respectively. All piglets in groups B to E were orally challenged with virulent wild-type Stx2e⁺ F18⁺ E. coli isolates at 5 weeks of age (4 WPPI). Serum IgG titers in groups D and E were significantly increased from 2 WPPI until the end of the study. Furthermore, no clinical signs were observed in groups A and E during the 7 days following the challenge, while clinical signs of ED were observed in 80%, 60%, and 20% of piglets in groups B, C, and D, respectively. These results indicate that intramuscular vaccination with 100 μg/piglet of the recombinant modified Stx2e toxoid can provide effective protection against ED in piglets.

Purpose: This study investigated the effects of e-health literacy, technostress, and subjective health status on health promotion behaviors of older adults. Methods: Data were collected from October to November, 2023, through structured questionnaires at seven senior welfare centers in J city. A total of 156 valid responses were analyzed. Descriptive statistics, independent t-tests, one-way ANOVA with Scheffé post hoc tests, Pearson’s correlation coefficients, and multiple regression analyses were conducted using SPSS version 29.0. Results: E-health literacy, technostress, and subjective health status were significantly associated with health promotion behaviors. Collectively, these factors explained 29% of the variance in older adults’ health promotion behaviors (F=22.54, p<.001). Conclusion: Intervention strategies to effectively promote health behaviors of older adults, should focus on enhancing e-health literacy, reducing technostress, and improving perceived health status. Scenarios based on the findings of this study should be developed and implemented in future nursing simulation education to strengthen learners’ competence in geriatric care.

This study aims to identify latent classes among shared e-scooter users based on their characteristics and analyze the differences in personal and usage characteristics across these classes. Specifically, the study has the following key objectives: (1) to select variables related to the personal and usage characteristics of shared e-scooter users; (2) to collect data on the personal and usage characteristics of shared e-scooter users; (3) to derive the latent classes of shared e-scooter users; and (4) to test the differences in personal and usage characteristics across the identified latent classes. Variables related to the personal and usage characteristics of shared e-scooter users were selected based on a literature review. Through a survey, data on the personal and usage characteristics of shared e-scooter users were collected. A latent class analysis (LCA) was performed to derive the latent classes of shared e-scooter users. Finally, a chi-square analysis was conducted to test the differences in personal and usage characteristics across the latent classes of shared e-scooter users. The results of this study are as follows. The personal characteristics of shared e-scooter users were identified as age and sex, whereas the usage characteristics were identified as usage frequency, time periods of e-scooter usage, return/rental zones, return/rental places, and types of roads used. Data on sex, age, usage frequency, periods of e-scooter usage, and return/rental locations were collected from 278 shared e-scooter users. Based on information criterion, statistical validation, and the entropy index, four latent classes of shared e-scooter users were identified: “male users with a commuting purpose in business zones,” “male users with a homeward commuting purpose in residential zones,” “female users with a leisure purpose in park/green zones,” and “users in their 20s with a commuting purpose in residential zones.” The results of a chisquare analysis revealed statistically significant differences (p < 0.05) in the personal and usage characteristics across the latent classes. Shared e-scooter user types were classified through Latent Class Analysis (LCA), and differences in personal and usage characteristics were identified across the classes. The preferred usage environments and conditions for each class of shared e-scooter users are determined. Variables related to the return/rental zone and periods of e-scooter usage showed the most significant differences among the classes. These findings can contribute to the development of customized user policies and the improvement of services based on the characteristics of shared e-scooter users.

In the evolving global food industry, international certifications have become essential for seafood export companies to ensure product safety, quality, and sustainability, as well as to meet consumer demands and regulatory standards. This study analyzes the decision-making factors influencing the acquisition and maintenance of international certifications among Korean seafood export companies, using decision tree analysis. The research surveyed 134 seafood export companies, focusing on six key factors: corporate characteristics, environmental factors, input factors, organizational structure, company capabilities, and external relationships. The decision tree analysis revealed that among corporate characteristics, the size of sales revenue, number of employees, and proportion of exports were found to play significant roles. For environmental factors, specific demands from overseas buyers, shifting consumer preferences, and compliance with global standards were identified as having a major impact. Regarding input factors, certification costs, validity periods, and investments in processing facilities were revealed to be critical variables. Organizational factors such as managerial support and dedicated personnel, capability factors like inter-departmental collaboration and processing system capacity, and relationship factors including partnerships with certification and export support agencies were also critical in the certification process. This study identified various factors influencing the decision-making process for acquiring and maintaining international certifications among Korean seafood export companies and analyzed the importance of detailed variables for the first time. Additionally, it provides practical and policy-oriented implications to promote the adoption of international certifications as part of efforts to enhance the global competitiveness of Korean seafood. Furthermore, this study contributes to the academic understanding of the decision-making process related to international certifications in seafood export companies.

In this study, we analyze the design preferences of parking spaces for shared e-scooters. The detailed purposes are to develop the attributes and attribute levels for the design of shared e-scooter parking spaces, derive profiles by combining the attributes and attribute levels of parking space design, collect preference data on parking-space design from shared e-scooter users, and analyze the preferences for parking space design. The attributes and attribute levels for the design of shared e-scooter parking spaces were developed based on a literature review and an investigation of shared e-scooter parking spaces. Using the full profile method and orthogonal design, the profiles were derived by combining the attribute levels. Preference data for parking space profiles were collected from shared e-scooter users using survey cards to visualize the profiles. Preferences for parking-space design were analyzed using conjoint analysis. Through a literature review and case studies, three attributes: parking angle and direction, parking unit, and parking method, along with their attribute levels were developed. By combining the attributes and their levels, 16 profiles for parking spaces were created. Preference data for these parking-space profiles were collected from 278 shared e-scooter users using a 10-point Likert scale. Using conjoint analysis, the utility and importance of the attributes and attribute levels for parking space design were analyzed. A parking-space design plan that considers the preferences of shared e-scooter users was proposed. The utilities of the attribute levels for shared e-scooter parking space design were derived. Among the attribute levels, the 'compact parking unit' showed the highest utility for the parking unit, whereas 'head-in parking' had the highest utility for the parking method. For parking angle and direction, 'perpendicular parking' had the highest utility, followed by '45°, direction toward the facility’s passageway.' The importance of the attributes for shared e-scooter parking space design was also derived, with 'parking angle and direction' being the most important attribute. Finally, a parking space design plan for shared e-scooters was proposed using visualized survey cards.

현재 기후변화 문제 해결을 위한 국제적 목표 및 국내 에너지 정책에 부합하는 LNG 발전의 효율성을 극대화하는 방안이 요구 되고 있다. 2050년 탄소중립 목표 달성을 위해 각국은 2030년까지 온실가스 감축 목표를 설정하였고, 국내에서도 석탄 발전 시설을 단계 적으로 폐쇄하고 LNG 발전 시설을 확대하려는 노력이 진행되고 있다. 이 연구에서는 LNG의 재기화 과정에서 발생하는 냉열을 회수하여 Carbon Capture and Storage, Ammonia-water Rankine Cycle / Kalina Cycle, Data Center Cooling, Direct Expansion 공정에 활용할 수 있는 시스템을 제안하였다. 연구 결과 제안된 시스템의 3E 분석 결과 Energy 효율 51.52%, Exergy 효율 42.74%, 환경적 측면에서 2,145.8 gCO2 / kgLNG의 탄 소 배출량을 보여 가장 우수한 성능을 확인하였다. 이를통해 본 연구에서 새롭게 제시한 시스템은 Energy, Exergy, 환경성 측면에서 강점을 가지며, 향후 기후변화 대응에 크게 기여할 것으로 판단된다.

본 연구는 중국　골프　시장　극대화　성정하고　있는　상황에서　골프　앱　어포던스　특성에　 대한　이용자의　인식이　이용자　몰입감과　e-지속사용의도에　어떠한　영향을　미치는지　파악해　보는데　 있다. 조사 대상은 2022년 ６월 1일 ~ 8월 1일까지 중국선전(深圳), 싼야(三亚), 쑤저우(苏州)에 골프 앱 사용중인 총 504명의 모집단을 선정하였다. 자료분석은 SPSS 25.0을 활용하였다. 또한, 빈도분석과 신뢰도 분석, 탐색적 요인분석, 상관분석 및 다중회귀분석을 통하여 각 요인 간의 영향 관계를 살펴보았다. 연구결 과 첫째, 골프 앱 어포던스의 하위요인별 감각적 어포던스, 기능적 어포던스, 인지적 어포던스가 즐거움 및 주의집중에 통계적으로 유의한 영향을 미치는 것으로 나타났다. 둘째, 몰입감의 하위요인별 즐거움, 주의집 중이 사용만족도　및 재사용의도에 통계적으로 유의한 영향을 미치는 것으로 나타났다. 셋째, 즐거움, 주의 집중은 골프 앱 어포던스의 하위요인별 인지적, 감각적, 기능적 어포던스가 사용만족도 및 재사용의도에 미치는 영향을 매개하는 것으로 나타났다.

이 논문은 남한지역을 대상으로 전기청동기시대의 주거와 환호, 청동기 부장 분묘, 대형 주구묘와 군집묘의 형성, 청동기 소유 주거, 환구 취락의 조성과 운영 등에 주목하여 당시의 사회구조에 대해서 검토한 글이다. 주거공간에서 확인되는 주거 간의 차별화는 취락을 이끄는 지도자 또는 유력자 및 그 의 가족들과 나머지 취락 구성원 간의 차이를 반영하는 것으로 파악하였다. 내환호와 외환호를 경계 로 배치된 대형 주거와 소형 주거의 분포 양상을 갖는 환호취락의 사례가 이를 잘 보여준다. 청동기를 소유한 주거의 존재와 청동 무기를 부장한 분묘의 등장은 요동지역 비파형동검문화와 관련된 것으로 긴장, 갈등, 대립 관계의 산물이면서 당시 사회의 계층분화적, 무장적 성격을 반영한다. 신성한 의례 공간인 환구, 그리고 이와 관련한 대형 가옥의 배치 양상은 엘리트 제사장의 존재를 추정할 수 있는 근거로 볼 수 있다. 이를 통해서 볼 때 전기청동기시대의 사회구조는 상위계층과 일반계층으로 구성 된 것으로 추정된다. 상위계층은 취락의 지도자(권위자)이면서 제사장의 성격을 가지는데, 이 상위계 층의 지위는 한시적인 성취 지위에 해당한다. 남한지역의 전기청동기 사회는 복합사회로 향해가는 긴 여정에서 중요한 기폭제가 되는 시기로 볼 수 있다. 이전 시기에 보이지 않았던 환호와 환구, 분묘와 청동기의 등장과 발전 양상은 전기청동기시대가 사회복합도가 증가한 서열사회에 해당한다는 것을 말 해준다.