• Korean Journal of Radiology
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• v.24 no.12
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• pp.1284-1292
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• 2023

Objective: We investigated the impacts of computed tomography (CT) added to ultrasound (US) for preoperative evaluation of patients with papillary thyroid carcinoma (PTC) on staging, surgical extent, and postsurgical survival. Materials and Methods: Consecutive patients who underwent surgery for PTC between January 2015 and December 2015 were retrospectively identified. Of them, 584 had undergone preoperative additional thyroid CT imaging (CT + US group), and 859 had not (US group). Inverse probability of treatment weighting (IPTW) and propensity score matching (PSM) were used to adjust for 14 variables and balance the two groups. Changes in nodal staging and surgical extent caused by CT were recorded. The recurrence-free survival and distant metastasis-free survival after surgery were compared between the two groups. Results: In the CT + US group, discordant nodal staging results between CT and US were observed in 94 of 584 patients (16.1%). Of them, CT accurately diagnosed nodal staging in 54 patients (57.4%), while the US provided incorrect nodal staging. Ten patients (1.7%) had a change in the extent of surgery based on CT findings. Postsurgical recurrence developed in 3.6% (31 of 859) of the CT + US group and 2.9% (17 of 584) of the US group during the median follow-up of 59 months. After adjustment using IPTW (580 vs. 861 patients), the CT + US group showed significantly higher recurrence-free survival rates than the US group (hazard ratio [HR], 0.52 [95% confidence interval {CI}, 0.29-0.96]; P = 0.037). PSM analysis (535 patients in each group) showed similar HR without statistical significance (HR, 0.60 [95% CI, 0.31-1.17]; P = 0.134). For distant metastasis-free survival, HRs after IPTW and PSM were 0.75 (95% CI, 0.17-3.36; P = 0.71) and 0.87 (95% CI, 0.20-3.80; P = 0.851), respectively. Conclusion: The addition of CT imaging for preoperative evaluation changed nodal staging and surgical extent and might improve recurrence-free survival in patients with PTC.

• Korean Journal of Radiology
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• v.23 no.11
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• pp.1067-1077
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• 2022

Objective: To determine whether Sonazoid-enhanced ultrasound (SZUS) was noninferior to SonoVue-enhanced ultrasound (SVUS) in diagnosing hepatocellular carcinoma (HCC) using the same diagnostic criteria. Materials and Methods: This prospective, single-center, noninferiority study (NCT04847726) enrolled 105 at-risk participants (71 male; mean age ± standard deviation, 63 ± 11 years; range, 26-86 years) with treatment-naïve solid hepatic nodules (≥ 1 cm). All participants underwent same-day SZUS (experimental method) and SVUS (control method) for one representative nodule per participant. Images were interpreted by three readers (the operator and two independent readers). All malignancies were diagnosed histopathologically, while the benignity of other lesions was confirmed by follow-up stability or pathology. The primary endpoint was per-lesion diagnostic accuracy for HCC pooled across three readers using the conventional contrast-enhanced ultrasound diagnostic criteria, including arterial phase hyperenhancement followed by mild (assessed within 2 minutes after contrast injection) and late (≥ 60 seconds with a delay of 5 minutes) washout. The noninferiority delta was -10%p. Furthermore, different time delays were compared as washout criteria in SZUS, including delays of 2, 5, and > 10 minutes. Results: A total of 105 lesions (HCCs [n = 61], non-HCC malignancies [n = 19], and benign [n = 25]) were evaluated. Using the 5-minutes washout criterion, per-lesion accuracy of SZUS pooled across the three readers (72.4%; 95% confidence interval [CI], 64.1%-79.3%) was noninferior to that of SVUS (71.4%; 95% CI, 63.1%-78.6%), meeting the statistical criterion for non-inferiority (difference of 0.95%p; 95% CI, -3.8%p-5.7%p). The arterial phase hyperenhancement combined with the 5-minutes washout criterion showed the same sensitivity as that of the > 10-minutes criterion (59.0% vs. 59.0%, p = 0.989), and the specificities were not significantly different (90.9% vs. 86.4%, p = 0.072). Conclusion: SZUS was noninferior to SVUS for diagnosing HCC in at-risk patients using the same diagnostic criteria. No significant improvement in HCC diagnosis was observed by extending the washout time delay from 5 to 10 minutes.

• Annals of Occupational and Environmental Medicine
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• v.35
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• pp.38.1-38.10
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• 2023

Background: Hearing loss (HL) is linked to an elevated risk of cardiovascular diseases (CVDs). The pathogeneses of HL and CVD commonly involve inflammatory responses. Previous studies investigated elevated levels of inflammatory biomarkers in subjects with HL, however, their findings did not demonstrate statistical significance. In our cross-sectional and longitudinal study, we investigated the correlation between HL and increased high-sensitivity C-reactive protein (hsCRP) levels to determine how HL is associated with CVDs. Methods: We conducted a cross-sectional study with workers aged over 18 years who underwent health check-ups at our institution between 2012 and 2018 (n = 566,507), followed by conducting a longitudinal study of workers aged > 18 who underwent health checkups at least twice at our institution between 2012 and 2018 (n = 173,794). The definition of HL was as an average threshold of ≥ 20 dB in pure-tone air conduction at 0.5, 1.0, and 2.0 kHz in both ears. The incidence of increased hsCRP levels throughout the follow-up period was defined as a level exceeding 3 mg/L. Logistic regression and generalized estimating equations were performed to estimate the risk of increased hsCRP levels according to the occurrence of HL in groups stratified by age. Results: In the cross-sectional study, the multivariate-adjusted odds ratio (OR) was 1.17 (95% confidence interval [CI]: 1.02-1.34); the OR was 0.99 (95% CI: 0.80-1.22) in those under 40 and 1.28 (1.08-1.53) in those over 40. In the longitudinal study, the multivariable-adjusted OR was 1.05 (95% CI: 0.92-1.19); the OR was 1.10 (95% CI: 0.90-1.35) in those under 40 and 1.20 (1.01-1.43) in those over 40. Conclusions: This cross-sectional and longitudinal study identified an association between HL and increased hsCRP levels in workers aged over 40 years.

• Journal of the Korean Society for Library and Information Science
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• v.58 no.2
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• pp.251-268
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• 2024

Recently, with the implementation of the "e-Government Performance Management Guidelines," there is a growing demand for setting performance indicators for information systems. For systems that provide information services to the public, such as CODIL, it is not easy to set performance indicators. This study presented a research model that applies Monte Carlo simulation to set expected performance targets that can be achieved through CODIL based on objective evidence. Among the survey contents conducted from 2015 to 2023, the statistical characteristics of user satisfaction regarding the frequency of use of construction technology information provided by CODIL were designated as input variables. Future expected targets and confidence intervals from 2024 to 2026 were designated as outcome variables. The expected target value was measured by generating 5 simulation alternatives and 1,000 random numbers for each alternative. Next, the measured expected goals were interpreted and compared with the results of time series regression analysis measured in previous studies. Although, as in previous studies, the expected target value could not be predicted based on time series regression analysis that considers the correlation between years. However, compared to previous studies, this study can be considered a more accurate analysis result because it predicted the expected target value based on 5,000 input variables.

• Journal of the Korean Society of Radiology
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• v.84 no.3
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• pp.627-637
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• 2023

Purpose To investigate the effect of patient positioning on tendinosis grade, visible range, and infraspinatus tendon (IST) thickness, and to determine the feasibility of internal rotation (IR) position to assess IST on ultrasound (US). Materials and Methods This study included 52 shoulders of 48 subjects who were evaluated for IST in three different positions: neutral position (N), IR, and position with the ipsilateral hand on the contralateral shoulder (HC). Two radiologists retrospectively graded IST tendinosis from grade 0 to grade 3 and the visible range from grade 1 to grade 4. The thickness of the IST was measured by another radiologist with a short-axis view. A generalized estimating equation was used for statistical analysis. Results The tendinosis grades were higher in the HC position than in the IR position, with a cumulative odds ratio of 2.087 (p = 0.004, 95% confidence interval [CI]: 1.268-3.433). The tendinosis grades in the HC position (p = 0.370) and IR position (p = 0.146) were not significantly different from those in the N position. The overall difference in IST thickness was significant (p < 0.001), but the visible range (p = 0.530) was not significantly different according to position. Conclusion Patient positioning significantly affected the grade of tendinosis and thickness but not the visible range of the IST. The IR position is a feasible position for assessing the IST on US.

• Journal of Christian Education in Korea
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• v.78
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• pp.213-229
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• 2024

Purpose of Study : The purpose of this study is to verify whether self-control has a mediating effect on the influence of grit on college students' self-efficacy, which has a significant impact on academic achievement. Research content and methods : In order to verify the influence of grit and self-control on college students' self-efficacy, this study first selected measurement tools for self-efficacy, grit, and self-control and created an online questionnaire. Next, a survey was conducted on 128 students at University A in Chungcheongnam-do. Descriptive statistical analysis and bivariate correlation analysis were performed on the collected data to verify the normality of the data and multicollinearity between factors. In addition, multiple regression analysis was used to verify the influence of grit and self-control on self-efficacy. Next, the effect of grit on self-efficacy was analyzed using structural equation modeling to verify whether self-control mediates it. As a result of the analysis, overall self-efficacy was influenced by the reliability of self-control and academic passion of grit. Self-confidence, a sub-factor of self-efficacy, was influenced by reliability of self-control and academic passion of grit. Self-regulation efficacy was influenced by the reliability of self-control and academic persistence of grit. Preference for task difficulty was influenced by grit, maintenance of academic interest, and self-control. Next, self-control was found to mediate the effect of grit on self-efficacy. Conclusion and Recommendations : This study explored the effects of grit and self-control on college students' self-efficacy. As a result, grit and self-control had a positive effect on self-efficacy. Additionally, self-control was found to mediate the effect of grit on self-efficacy. This study proposes to support grit and self-control in order to support successful academic achievement of college students.

• Journal of Practical Engineering Education
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• v.16 no.4
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• pp.471-479
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• 2024

This study aims to examine the cognitive and affective changes in university students' writing self-efficacy when engaging in reflective writing classes utilizing ChatGPT. Over ten sessions, reflective writing classes using ChatGPT were conducted for students enrolled in a mandatory writing course at S University in Gyeonggi Province. The reflective journals written by the students during these sessions were meticulously reviewed as qualitative data with statistical analysis of pre- and post-surveys on writing self-efficacy. The results confirmed that utilizing ChatGPT in reflective writing classes positively impacted students' writing self-efficacy. Participants showed increased interest and confidence in their writing abilities when using ChatGPT. It was reported that they received cognitive assistance in outlining and paragraph structuring from samples generated by ChatGPT. Although survey results showed an overall increase in writing self-efficacy, the only statistically significant change was in the 'plagiarism response' category, which means a clear awareness of plagiarism issues. The process of personalizing the ChatGPT-generated samples requires consistent practice, and systematic guidelines on using such helpful tool effectively should be reinforced as a future task.

• Journal of Society of Preventive Korean Medicine
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• v.28 no.2
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• pp.151-164
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• 2024

Objectives : Using MMSE and MoCA cognitive tools, this study tried to measure the effect of acupuncture differing by cognitive types. Through the method of PRISMA literature review, this study aimed to understand and improve the acupuncture's effectiveness in its application. Methods : The research method was a literature review and Cochrane meta-analysis of papers on the effectiveness of acupuncture treatments for mild cognitive impairment conducted from 2012 to 2023. The Cochrane risk of bias (RoB) tool was used as a quality analysis tool, and the meta-analysis tool was Cochrane RevMan V5.4.1 software. Results : As a result of the study, a total of 967 subjects were used for analysis, and 16 papers on randomized acupuncture trials were analyzed. The results are as follows: As a result of meta-analysis of acupuncture intervention for mild cognitive impairment, the MMSE score had an average of 1.61 with a 95% confidence interval ranging from 0.14 to 3.07, and a statistically significant result with p<0.001. The Z-score was 2.15, which corresponded to a p-value of 0.03. The MoCA score had an average range between 0.39 and 2.49, also showing statistical significance with p<0.001, and a Z-score of 2.70 (p=0.007). The effect of acupuncture in subjects with mild cognitive impairment was significant. Conclusion : The suggestions and conclusion indicate that acupuncture intervention has a significant effect on mild cognitive impairment. This study propose future experimental research on various types of acupuncture interventions for mild cognitive impairment. The significance of this study is that it presented basic data for the development of a preventive convergence cognitive intervention program for patients with mild cognitive impairment in the community.

• Journal of the Korean Applied Science and Technology
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• v.41 no.3
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• pp.634-647
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• 2024

This study collected 411 copies of data from women in their 20s and 30s in Seoul and Gyeonggi Province who had received non-face-to-face counseling services from beauty influencer and analyzed them with the SPSS WIN 20.0 statistical program. The purpose of the study was to identify the effect of non-face-to-face consultation service quality on customer reliability and purchasing behavior, analyze the mediating effect of customer reliability, and provide basic data necessary for establishing beauty and cosmetics marketing strategies. As a result of the study, first, it can be seen that the main purpose of use of the beauty influencer non-face-to-face counseling service differs according to age, occupation, and average monthly income. Second, correlations between each variable appeared. Third, it was found that the higher the quality of non-face-to-face counseling services of beauty influencer, the higher the purchasing behavior. Fourth, the higher the customer reliability, the higher the purchasing behavior. Fifth, in the relationship between non-face-to-face counseling service quality and purchasing behavior of beauty influencer, customer trust was confirmed to have a partial mediating effect. In the future, it is hoped that the results of this study will be useful as basic data for establishing beauty and cosmetics marketing strategies.

• Asia pacific journal of information systems
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• v.18 no.3
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• pp.91-121
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• 2008

Electronic commerce, commonly known as e-commerce or eCommerce, has become a major business trend in these days. The amount of trade conducted electronically has grown extraordinarily by developing the Internet technology. Most electronic commerce has being conducted between businesses to customers; therefore, the researches with respect to e-commerce are to find customer's needs, behaviors through statistical methods. However, the statistical researches, mostly based on a questionnaire, are the static researches, They can tell us the dynamic relationships between initial purchasing and repurchasing. Therefore, this study proposes dynamic research model for analyzing the cause of initial purchasing and repurchasing. This paper is based on the System-Dynamic theory, using the powerful simulation model with some restriction, The restrictions are based on the theory TAM(Technology Acceptance Model), PAM, and TPB(Theory of Planned Behavior). This article investigates not only the customer's purchasing and repurchasing behavior by passing of time but also the interactive effects to one another. This research model has six scenarios and three steps for analyzing customer behaviors. The first step is the research of purchasing situations. The second step is the research of repurchasing situations. Finally, the third step is to study the relationship between initial purchasing and repurchasing. The purpose of six scenarios is to find the customer's purchasing patterns according to the environmental changes. We set six variables in these scenarios by (1) changing the number of products; (2) changing the number of contents in on-line shopping malls; (3) having multimedia files or not in the shopping mall web sites; (4) grading on-line communities; (5) changing the qualities of products; (6) changing the customer's degree of confidence on products. First three variables are applied to study customer's purchasing behavior, and the other variables are applied to repurchasing behavior study. Through the simulation study, this paper presents some inter-relational result about customer purchasing behaviors, For example, Active community actions are not the increasing factor of purchasing but the increasing factor of word of mouth effect, Additionally. The higher products' quality, the more word of mouth effects increase. The number of products and contents on the web sites have same influence on people's buying behaviors. All simulation methods in this paper is not only display the result of each scenario but also find how to affect each other. Hence, electronic commerce firm can make more realistic marketing strategy about consumer behavior through this dynamic simulation research. Moreover, dynamic analysis method can predict the results which help the decision of marketing strategy by using the time-line graph. Consequently, this dynamic simulation analysis could be a useful research model to make firm's competitive advantage. However, this simulation model needs more further study. With respect to reality, this simulation model has some limitations. There are some missing factors which affect customer's buying behaviors in this model. The first missing factor is the customer's degree of recognition of brands. The second factor is the degree of customer satisfaction. The third factor is the power of word of mouth in the specific region. Generally, word of mouth affects significantly on a region's culture, even people's buying behaviors. The last missing factor is the user interface environment in the internet or other on-line shopping tools. In order to get more realistic result, these factors might be essential matters to make better research in the future studies.